MediaFormat

public final class MediaFormat
extends Object

java.lang.Object
   ↳ android.media.MediaFormat


Encapsulates the information describing the format of media data, be it audio or video, as well as optional feature metadata.

The format of the media data is specified as key/value pairs. Keys are strings. Values can be integer, long, float, String or ByteBuffer.

The feature metadata is specificed as string/boolean pairs.

Keys common to all audio/video formats, all keys not marked optional are mandatory:

NameValue TypeDescription
KEY_MIMEStringThe type of the format.
KEY_CODECS_STRINGStringoptional, the RFC 6381 codecs string of the MediaFormat
KEY_MAX_INPUT_SIZEIntegeroptional, maximum size of a buffer of input data
KEY_PIXEL_ASPECT_RATIO_WIDTHIntegeroptional, the pixel aspect ratio width
KEY_PIXEL_ASPECT_RATIO_HEIGHTIntegeroptional, the pixel aspect ratio height
KEY_BIT_RATEIntegerencoder-only, desired bitrate in bits/second
KEY_DURATIONlongthe duration of the content (in microseconds)
Video formats have the following keys:
NameValue TypeDescription
KEY_WIDTHInteger
KEY_HEIGHTInteger
KEY_COLOR_FORMATIntegerset by the user for encoders, readable in the output format of decoders
KEY_FRAME_RATEInteger or Floatrequired for encoders, optional for decoders
KEY_CAPTURE_RATEInteger
KEY_I_FRAME_INTERVALInteger (or Float)encoder-only, time-interval between key frames. Float support added in Build.VERSION_CODES.N_MR1
KEY_INTRA_REFRESH_PERIODIntegerencoder-only, optional
KEY_LATENCYIntegerencoder-only, optional
KEY_MAX_WIDTHIntegerdecoder-only, optional, max-resolution width
KEY_MAX_HEIGHTIntegerdecoder-only, optional, max-resolution height
KEY_REPEAT_PREVIOUS_FRAME_AFTERLongencoder in surface-mode only, optional
KEY_PUSH_BLANK_BUFFERS_ON_STOPInteger(1)decoder rendering to a surface only, optional
KEY_TEMPORAL_LAYERINGStringencoder only, optional, temporal-layering schema
Specify both KEY_MAX_WIDTH and KEY_MAX_HEIGHT to enable adaptive playback (seamless resolution change) for a video decoder that supports it (MediaCodecInfo.CodecCapabilities#FEATURE_AdaptivePlayback). The values are used as hints for the codec: they are the maximum expected resolution to prepare for. Depending on codec support, preparing for larger maximum resolution may require more memory even if that resolution is never reached. These fields have no effect for codecs that do not support adaptive playback.

Audio formats have the following keys:
NameValue TypeDescription
KEY_CHANNEL_COUNTInteger
KEY_SAMPLE_RATEInteger
KEY_PCM_ENCODINGIntegeroptional
KEY_IS_ADTSIntegeroptional, if decoding AAC audio content, setting this key to 1 indicates that each audio frame is prefixed by the ADTS header.
KEY_AAC_PROFILEIntegerencoder-only, optional, if content is AAC audio, specifies the desired profile.
KEY_AAC_SBR_MODEIntegerencoder-only, optional, if content is AAC audio, specifies the desired SBR mode.
KEY_AAC_DRC_TARGET_REFERENCE_LEVELIntegerdecoder-only, optional, if content is AAC audio, specifies the target reference level.
KEY_AAC_ENCODED_TARGET_LEVELIntegerdecoder-only, optional, if content is AAC audio, specifies the target reference level used at encoder.
KEY_AAC_DRC_BOOST_FACTORIntegerdecoder-only, optional, if content is AAC audio, specifies the DRC boost factor.
KEY_AAC_DRC_ATTENUATION_FACTORIntegerdecoder-only, optional, if content is AAC audio, specifies the DRC attenuation factor.
KEY_AAC_DRC_HEAVY_COMPRESSIONIntegerdecoder-only, optional, if content is AAC audio, specifies whether to use heavy compression.
KEY_AAC_MAX_OUTPUT_CHANNEL_COUNTIntegerdecoder-only, optional, if content is AAC audio, specifies the maximum number of channels the decoder outputs.
KEY_AAC_DRC_EFFECT_TYPEIntegerdecoder-only, optional, if content is AAC audio, specifies the MPEG-D DRC effect type to use.
KEY_AAC_DRC_OUTPUT_LOUDNESSIntegerdecoder-only, optional, if content is AAC audio, returns the DRC output loudness.
KEY_AAC_DRC_ALBUM_MODEIntegerdecoder-only, optional, if content is AAC audio, specifies the whether MPEG-D DRC Album Mode is active or not.
KEY_CHANNEL_MASKIntegeroptional, a mask of audio channel assignments
KEY_ENCODER_DELAYIntegeroptional, the number of frames to trim from the start of the decoded audio stream.
KEY_ENCODER_PADDINGIntegeroptional, the number of frames to trim from the end of the decoded audio stream.
KEY_FLAC_COMPRESSION_LEVELIntegerencoder-only, optional, if content is FLAC audio, specifies the desired compression level.
KEY_MPEGH_PROFILE_LEVEL_INDICATIONInteger decoder-only, optional, if content is MPEG-H audio, specifies the profile and level of the stream.
KEY_MPEGH_COMPATIBLE_SETSByteBuffer decoder-only, optional, if content is MPEG-H audio, specifies the compatible sets (profile and level) of the stream.
KEY_MPEGH_REFERENCE_CHANNEL_LAYOUT Integerdecoder-only, optional, if content is MPEG-H audio, specifies the preferred reference channel layout of the stream.
Subtitle formats have the following keys:
KEY_MIMEStringThe type of the format.
KEY_LANGUAGEStringThe language of the content.
KEY_CAPTION_SERVICE_NUMBERintoptional, the closed-caption service or channel number.
Image formats have the following keys:
KEY_MIMEStringThe type of the format.
KEY_WIDTHInteger
KEY_HEIGHTInteger
KEY_COLOR_FORMATIntegerset by the user for encoders, readable in the output format of decoders
KEY_TILE_WIDTHIntegerrequired if the image has grid
KEY_TILE_HEIGHTIntegerrequired if the image has grid
KEY_GRID_ROWSIntegerrequired if the image has grid
KEY_GRID_COLUMNSIntegerrequired if the image has grid

Summary

Constants

int COLOR_RANGE_FULL

Full range.

int COLOR_RANGE_LIMITED

Limited range.

int COLOR_STANDARD_BT2020

BT.2020 color chromacity coordinates with KR = 0.2627, KB = 0.0593.

int COLOR_STANDARD_BT601_NTSC

BT.601 525 color chromacity coordinates with KR = 0.299, KB = 0.114.

int COLOR_STANDARD_BT601_PAL

BT.601 625 color chromacity coordinates with KR = 0.299, KB = 0.114.

int COLOR_STANDARD_BT709

BT.709 color chromacity coordinates with KR = 0.2126, KB = 0.0722.

int COLOR_TRANSFER_HLG

ARIB STD-B67 hybrid-log-gamma transfer function.

int COLOR_TRANSFER_LINEAR

Linear transfer characteristic curve.

int COLOR_TRANSFER_SDR_VIDEO

SMPTE 170M transfer characteristic curve used by BT.601/BT.709/BT.2020.

int COLOR_TRANSFER_ST2084

SMPTE ST 2084 transfer function.

String KEY_AAC_DRC_ALBUM_MODE

A key describing the album mode for MPEG-D DRC as defined in ISO/IEC 23003-4.

String KEY_AAC_DRC_ATTENUATION_FACTOR

A key describing the attenuation factor allowing to adapt the dynamics of the output to the actual listening requirements.

String KEY_AAC_DRC_BOOST_FACTOR

A key describing the boost factor allowing to adapt the dynamics of the output to the actual listening requirements.

String KEY_AAC_DRC_EFFECT_TYPE

A key describing for selecting the DRC effect type for MPEG-D DRC.

String KEY_AAC_DRC_HEAVY_COMPRESSION

A key describing the selection of the heavy compression profile for MPEG-4 DRC.

String KEY_AAC_DRC_OUTPUT_LOUDNESS

A key to retrieve the output loudness of a decoded bitstream.

String KEY_AAC_DRC_TARGET_REFERENCE_LEVEL

A key describing the Target Reference Level (Target Loudness).

String KEY_AAC_ENCODED_TARGET_LEVEL

A key describing the target reference level that was assumed at the encoder for calculation of attenuation gains for clipping prevention.

String KEY_AAC_MAX_OUTPUT_CHANNEL_COUNT

This constant was deprecated in API level 33. Use the non-AAC-specific key KEY_MAX_OUTPUT_CHANNEL_COUNT instead

String KEY_AAC_PROFILE

A key describing the AAC profile to be used (AAC audio formats only).

String KEY_AAC_SBR_MODE

A key describing the AAC SBR mode to be used (AAC audio formats only).

String KEY_ALLOW_FRAME_DROP

A key for applications to opt out of allowing a Surface to discard undisplayed/unconsumed frames as means to catch up after falling behind.

String KEY_AUDIO_SESSION_ID

A key describing the audio session ID of the AudioTrack associated to a tunneled video codec.

String KEY_BITRATE_MODE

A key describing the desired bitrate mode to be used by an encoder.

String KEY_BIT_RATE

A key describing the average bitrate in bits/sec.

String KEY_CAPTION_SERVICE_NUMBER

A key describing the closed caption service number.

String KEY_CAPTURE_RATE

A key describing the capture rate of a video format in frames/sec.

String KEY_CHANNEL_COUNT

A key describing the number of channels in an audio format.

String KEY_CHANNEL_MASK

A key describing the channel composition of audio content.

String KEY_CODECS_STRING

A key describing the codecs string of the MediaFormat.

String KEY_COLOR_FORMAT

A key describing the color format of the content in a video format.

String KEY_COLOR_RANGE

An optional key describing the range of the component values of the video content.

String KEY_COLOR_STANDARD

An optional key describing the color primaries, white point and luminance factors for video content.

String KEY_COLOR_TRANSFER

An optional key describing the opto-electronic transfer function used for the video content.

String KEY_COLOR_TRANSFER_REQUEST

An optional key describing the opto-electronic transfer function requested for the output video content.

String KEY_COMPLEXITY

A key describing the encoding complexity.

String KEY_CREATE_INPUT_SURFACE_SUSPENDED

If specified when configuring a video encoder that's in "surface-input" mode, it will instruct the encoder to put the surface source in suspended state when it's connected.

String KEY_CROP_BOTTOM

A key describing the bottom-coordinate (y) of the crop rectangle.

String KEY_CROP_LEFT

A key describing the left-coordinate (x) of the crop rectangle.

String KEY_CROP_RIGHT

A key describing the right-coordinate (x) of the crop rectangle.

String KEY_CROP_TOP

A key describing the top-coordinate (y) of the crop rectangle.

String KEY_DURATION

A key describing the duration (in microseconds) of the content.

String KEY_ENCODER_DELAY

A key describing the number of frames to trim from the start of the decoded audio stream.

String KEY_ENCODER_PADDING

A key describing the number of frames to trim from the end of the decoded audio stream.

String KEY_FLAC_COMPRESSION_LEVEL

A key describing the FLAC compression level to be used (FLAC audio format only).

String KEY_FRAME_RATE

A key describing the frame rate of a video format in frames/sec.

String KEY_GRID_COLUMNS

A key describing the number of grid columns in the content in a MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF track.

String KEY_GRID_ROWS

A key describing the number of grid rows in the content in a MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF track.

String KEY_HAPTIC_CHANNEL_COUNT

A key describing the number of haptic channels in an audio format.

String KEY_HARDWARE_AV_SYNC_ID

A key describing the hardware AV sync id.

String KEY_HDR10_PLUS_INFO

An optional key describing the HDR10+ metadata of the video content.

String KEY_HDR_STATIC_INFO

An optional key describing the static metadata of HDR (high-dynamic-range) video content.

String KEY_HEIGHT

A key describing the height of the content in a video format.

String KEY_INTRA_REFRESH_PERIOD

An optional key describing the period of intra refresh in frames.

String KEY_IS_ADTS

A key mapping to a value of 1 if the content is AAC audio and audio frames are prefixed with an ADTS header.

String KEY_IS_AUTOSELECT

A key for boolean AUTOSELECT behavior for the track.

String KEY_IS_DEFAULT

A key for boolean DEFAULT behavior for the track.

String KEY_IS_FORCED_SUBTITLE

A key for the FORCED field for subtitle tracks.

String KEY_I_FRAME_INTERVAL

A key describing the frequency of key frames expressed in seconds between key frames.

String KEY_LANGUAGE

A key describing the language of the content, using either ISO 639-1 or 639-2/T codes.

String KEY_LATENCY

An optional key describing the desired encoder latency in frames.

String KEY_LEVEL

A key describing the desired profile to be used by an encoder.

String KEY_LOW_LATENCY

An optional key describing the low latency decoding mode.

String KEY_MAX_B_FRAMES

A key describing the maximum number of B frames between I or P frames, to be used by a video encoder.

String KEY_MAX_FPS_TO_ENCODER

Instruct the video encoder in "surface-input" mode to drop excessive frames from the source, so that the input frame rate to the encoder does not exceed the specified fps.

String KEY_MAX_HEIGHT

A key describing the maximum expected height of the content in a video decoder format, in case there are resolution changes in the video content.

String KEY_MAX_INPUT_SIZE

A key describing the maximum size in bytes of a buffer of data described by this MediaFormat.

String KEY_MAX_OUTPUT_CHANNEL_COUNT

A key describing the maximum number of channels that can be output by an audio decoder.

String KEY_MAX_PTS_GAP_TO_ENCODER

Instruct the video encoder in "surface-input" mode to limit the gap of timestamp between any two adjacent frames fed to the encoder to the specified amount (in micro-second).

String KEY_MAX_WIDTH

A key describing the maximum expected width of the content in a video decoder format, in case there are resolution changes in the video content.

String KEY_MIME

A key describing the mime type of the MediaFormat.

String KEY_MPEGH_COMPATIBLE_SETS

A key describing the MPEG-H stream compatible sets.

String KEY_MPEGH_PROFILE_LEVEL_INDICATION

A key describing the MPEG-H stream profile-level indication.

String KEY_MPEGH_REFERENCE_CHANNEL_LAYOUT

A key describing the MPEG-H stream reference channel layout.

String KEY_OPERATING_RATE

A key describing the desired operating frame rate for video or sample rate for audio that the codec will need to operate at.

String KEY_OUTPUT_REORDER_DEPTH

An optional key describing the maximum number of non-display-order coded frames.

String KEY_PCM_ENCODING

A key describing the raw audio sample encoding/format.

String KEY_PICTURE_TYPE

A key describing the picture type of the encoded frame.

String KEY_PIXEL_ASPECT_RATIO_HEIGHT

A key describing the pixel aspect ratio height.

String KEY_PIXEL_ASPECT_RATIO_WIDTH

A key describing the pixel aspect ratio width.

String KEY_PREPEND_HEADER_TO_SYNC_FRAMES

An optional key describing whether encoders prepend headers to sync frames (e.g.

String KEY_PRIORITY

A key describing the desired codec priority.

String KEY_PROFILE

A key describing the desired profile to be used by an encoder.

String KEY_PUSH_BLANK_BUFFERS_ON_STOP

If specified when configuring a video decoder rendering to a surface, causes the decoder to output "blank", i.e.

String KEY_QUALITY

A key describing the desired encoding quality.

String KEY_REPEAT_PREVIOUS_FRAME_AFTER

Applies only when configuring a video encoder in "surface-input" mode.

String KEY_ROTATION

A key describing the desired clockwise rotation on an output surface.

String KEY_SAMPLE_RATE

A key describing the sample rate of an audio format.

String KEY_SLICE_HEIGHT

A key describing the plane height of a multi-planar (YUV) video bytebuffer layout.

String KEY_SLOW_MOTION_MARKERS

A key for retrieving the slow-motion marker information associated with a video track.

String KEY_STRIDE

A key describing the stride of the video bytebuffer layout.

String KEY_TEMPORAL_LAYERING

A key describing the temporal layering schema.

String KEY_TILE_HEIGHT

A key describing the height (in pixels) of each tile of the content in a MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF track.

String KEY_TILE_WIDTH

A key describing the width (in pixels) of each tile of the content in a MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF track.

String KEY_TRACK_ID

A key describing a unique ID for the content of a media track.

String KEY_VIDEO_ENCODING_STATISTICS_LEVEL

A key describing the level of encoding statistics information emitted from video encoder.

String KEY_VIDEO_QP_AVERAGE

A key describing the per-frame average block QP (Quantization Parameter).

String KEY_VIDEO_QP_B_MAX

A key describing the maximum Quantization Parameter allowed for encoding video.

String KEY_VIDEO_QP_B_MIN

A key describing the minimum Quantization Parameter allowed for encoding video.

String KEY_VIDEO_QP_I_MAX

A key describing the maximum Quantization Parameter allowed for encoding video.

String KEY_VIDEO_QP_I_MIN

A key describing the minimum Quantization Parameter allowed for encoding video.

String KEY_VIDEO_QP_MAX

A key describing the maximum Quantization Parameter allowed for encoding video.

String KEY_VIDEO_QP_MIN

A key describing the minimum Quantization Parameter allowed for encoding video.

String KEY_VIDEO_QP_P_MAX

A key describing the maximum Quantization Parameter allowed for encoding video.

String KEY_VIDEO_QP_P_MIN

A key describing the minimum Quantization Parameter allowed for encoding video.

String KEY_WIDTH

A key describing the width of the content in a video format.

String LOG_SESSION_ID

A key describing the log session ID for MediaCodec.

String MIMETYPE_AUDIO_AAC

String MIMETYPE_AUDIO_AAC_ELD

MIME type for AAC Enhanced Low Delay (ELD) audio stream.

String MIMETYPE_AUDIO_AAC_HE_V1

MIME type for HE-AAC v1 (LC + SBR) audio stream.

String MIMETYPE_AUDIO_AAC_HE_V2

MIME type for HE-AAC v2 (LC + SBR + PS) audio stream.

String MIMETYPE_AUDIO_AAC_LC

MIME type for AAC Low Complexity (LC) audio stream.

String MIMETYPE_AUDIO_AAC_XHE

MIME type for AAC XHE audio stream.

String MIMETYPE_AUDIO_AC3

String MIMETYPE_AUDIO_AC4

String MIMETYPE_AUDIO_AMR_NB

String MIMETYPE_AUDIO_AMR_WB

String MIMETYPE_AUDIO_DOLBY_MAT

MIME type for Dolby Metadata-enhanced Audio Transmission (MAT) audio stream.

String MIMETYPE_AUDIO_DOLBY_TRUEHD

MIME type for Dolby TrueHD audio format, based on Meridian Lossless Packing (MLP).

String MIMETYPE_AUDIO_DRA

MIME type for Dynamic Resolution Adaptation (DRA) audio stream.

String MIMETYPE_AUDIO_DTS

MIME type for DTS Digital Surround (up to 5.1 channels) audio stream, aka DTS-CA.

String MIMETYPE_AUDIO_DTS_HD

MIME type for DTS HD (up to 7.1 channels) audio stream.

String MIMETYPE_AUDIO_DTS_UHD

MIME type for DTS UHD (object-based) audio stream, aka DTS:X.

String MIMETYPE_AUDIO_EAC3

String MIMETYPE_AUDIO_EAC3_JOC

String MIMETYPE_AUDIO_FLAC

String MIMETYPE_AUDIO_G711_ALAW

String MIMETYPE_AUDIO_G711_MLAW

String MIMETYPE_AUDIO_IEC61937

MIME type for the IEC61937 audio stream encapsulation.

String MIMETYPE_AUDIO_MPEG

String MIMETYPE_AUDIO_MPEGH_BL_L3

MIME type for MPEG-H Baseline (BL) Profile L3 audio stream.

String MIMETYPE_AUDIO_MPEGH_BL_L4

MIME type for MPEG-H Baseline (BL) Profile L4 audio stream.

String MIMETYPE_AUDIO_MPEGH_LC_L3

MIME type for MPEG-H Low Complexity (LC) L3 audio stream.

String MIMETYPE_AUDIO_MPEGH_LC_L4

MIME type for MPEG-H Low Complexity (LC) L4 audio stream.

String MIMETYPE_AUDIO_MPEGH_MHA1

MIME type for MPEG-H Audio single stream

String MIMETYPE_AUDIO_MPEGH_MHM1

MIME type for MPEG-H Audio single stream, encapsulated in MHAS

String MIMETYPE_AUDIO_MSGSM

String MIMETYPE_AUDIO_OPUS

String MIMETYPE_AUDIO_QCELP

String MIMETYPE_AUDIO_RAW

String MIMETYPE_AUDIO_SCRAMBLED

String MIMETYPE_AUDIO_VORBIS

String MIMETYPE_IMAGE_ANDROID_HEIC

MIME type for HEIF still image data encoded in HEVC.

String MIMETYPE_IMAGE_AVIF

MIME type for AVIF still image data encoded in AV1.

String MIMETYPE_TEXT_CEA_608

MIME type for CEA-608 closed caption data.

String MIMETYPE_TEXT_CEA_708

MIME type for CEA-708 closed caption data.

String MIMETYPE_TEXT_SUBRIP

MIME type for SubRip (SRT) container.

String MIMETYPE_TEXT_VTT

MIME type for WebVTT subtitle data.

String MIMETYPE_VIDEO_AV1

String MIMETYPE_VIDEO_AVC

String MIMETYPE_VIDEO_DOLBY_VISION

String MIMETYPE_VIDEO_H263

String MIMETYPE_VIDEO_HEVC

String MIMETYPE_VIDEO_MPEG2

String MIMETYPE_VIDEO_MPEG4

String MIMETYPE_VIDEO_RAW

String MIMETYPE_VIDEO_SCRAMBLED

String MIMETYPE_VIDEO_VP8

String MIMETYPE_VIDEO_VP9

int PICTURE_TYPE_B

Picture Type is B Frame.

int PICTURE_TYPE_I

Picture Type is I Frame.

int PICTURE_TYPE_P

Picture Type is P Frame.

int PICTURE_TYPE_UNKNOWN

Picture Type is unknown.

int TYPE_BYTE_BUFFER

int TYPE_FLOAT

int TYPE_INTEGER

int TYPE_LONG

int TYPE_NULL

int TYPE_STRING

int VIDEO_ENCODING_STATISTICS_LEVEL_1

Encoding Statistics Level 1.

int VIDEO_ENCODING_STATISTICS_LEVEL_NONE

Encoding Statistics Level None.

Public constructors

MediaFormat()

Creates an empty MediaFormat

MediaFormat(MediaFormat other)

Create a copy of a media format object.

Public methods

boolean containsFeature(String name)

Returns true iff a feature of the given name exists in the format.

boolean containsKey(String name)

Returns true iff a key of the given name exists in the format.

static MediaFormat createAudioFormat(String mime, int sampleRate, int channelCount)

Creates a minimal audio format.

static MediaFormat createSubtitleFormat(String mime, String language)

Creates a minimal subtitle format.

static MediaFormat createVideoFormat(String mime, int width, int height)

Creates a minimal video format.

ByteBuffer getByteBuffer(String name)

Returns the value of a ByteBuffer key.

ByteBuffer getByteBuffer(String name, ByteBuffer defaultValue)

Returns the value of a ByteBuffer key, or the default value if the key is missing.

boolean getFeatureEnabled(String feature)

Returns whether a feature is to be enabled (true) or disabled (false).

Set<String> getFeatures()

Returns a Set view of the features contained in this MediaFormat.

float getFloat(String name, float defaultValue)

Returns the value of a float key, or the default value if the key is missing.

float getFloat(String name)

Returns the value of a float key.

int getInteger(String name)

Returns the value of an integer key.

int getInteger(String name, int defaultValue)

Returns the value of an integer key, or the default value if the key is missing.

Set<String> getKeys()

Returns a Set view of the keys contained in this MediaFormat.

long getLong(String name)

Returns the value of a long key.

long getLong(String name, long defaultValue)

Returns the value of a long key, or the default value if the key is missing.

Number getNumber(String name, Number defaultValue)

Returns the value of a numeric key, or the default value if the key is missing.

Number getNumber(String name)

Returns the value of a numeric key.

String getString(String name)

Returns the value of a string key.

String getString(String name, String defaultValue)

Returns the value of a string key, or the default value if the key is missing.

int getValueTypeForKey(String name)

Returns the value type for a key.

void removeFeature(String name)

Removes a given feature setting if present.

void removeKey(String name)

Removes a value of a given key if present.

void setByteBuffer(String name, ByteBuffer bytes)

Sets the value of a ByteBuffer key.

void setFeatureEnabled(String feature, boolean enabled)

Sets whether a feature is to be enabled (true) or disabled (false).

void setFloat(String name, float value)

Sets the value of a float key.

void setInteger(String name, int value)

Sets the value of an integer key.

void setLong(String name, long value)

Sets the value of a long key.

void setString(String name, String value)

Sets the value of a string key.

String toString()

Returns a string representation of the object.

Inherited methods

Constants

COLOR_RANGE_FULL

Added in API level 24
public static final int COLOR_RANGE_FULL

Full range. Y, Cr and Cb component values range from 0 to 255 for 8-bit content.

Constant Value: 1 (0x00000001)

COLOR_RANGE_LIMITED

Added in API level 24
public static final int COLOR_RANGE_LIMITED

Limited range. Y component values range from 16 to 235 for 8-bit content. Cr, Cy values range from 16 to 240 for 8-bit content. This is the default for video content.

Constant Value: 2 (0x00000002)

COLOR_STANDARD_BT2020

Added in API level 24
public static final int COLOR_STANDARD_BT2020

BT.2020 color chromacity coordinates with KR = 0.2627, KB = 0.0593.

Constant Value: 6 (0x00000006)

COLOR_STANDARD_BT601_NTSC

Added in API level 24
public static final int COLOR_STANDARD_BT601_NTSC

BT.601 525 color chromacity coordinates with KR = 0.299, KB = 0.114.

Constant Value: 4 (0x00000004)

COLOR_STANDARD_BT601_PAL

Added in API level 24
public static final int COLOR_STANDARD_BT601_PAL

BT.601 625 color chromacity coordinates with KR = 0.299, KB = 0.114.

Constant Value: 2 (0x00000002)

COLOR_STANDARD_BT709

Added in API level 24
public static final int COLOR_STANDARD_BT709

BT.709 color chromacity coordinates with KR = 0.2126, KB = 0.0722.

Constant Value: 1 (0x00000001)

COLOR_TRANSFER_HLG

Added in API level 24
public static final int COLOR_TRANSFER_HLG

ARIB STD-B67 hybrid-log-gamma transfer function. This is used by some HDR video content.

Constant Value: 7 (0x00000007)

COLOR_TRANSFER_LINEAR

Added in API level 24
public static final int COLOR_TRANSFER_LINEAR

Linear transfer characteristic curve.

Constant Value: 1 (0x00000001)

COLOR_TRANSFER_SDR_VIDEO

Added in API level 24
public static final int COLOR_TRANSFER_SDR_VIDEO

SMPTE 170M transfer characteristic curve used by BT.601/BT.709/BT.2020. This is the curve used by most non-HDR video content.

Constant Value: 3 (0x00000003)

COLOR_TRANSFER_ST2084

Added in API level 24
public static final int COLOR_TRANSFER_ST2084

SMPTE ST 2084 transfer function. This is used by some HDR video content.

Constant Value: 6 (0x00000006)

KEY_AAC_DRC_ALBUM_MODE

Added in API level 30
public static final String KEY_AAC_DRC_ALBUM_MODE

A key describing the album mode for MPEG-D DRC as defined in ISO/IEC 23003-4.

The associated value is an integer and can be set to following values:

ValueAlbum Mode
0disabled
1enabled

Disabled album mode leads to application of gain sequences for fading in and out, if provided in the bitstream. Enabled album mode makes use of dedicated album loudness information, if provided in the bitstream.

The default value is 0 (album mode disabled).

This key is only used during decoding.

Constant Value: "aac-drc-album-mode"

KEY_AAC_DRC_ATTENUATION_FACTOR

Added in API level 21
public static final String KEY_AAC_DRC_ATTENUATION_FACTOR

A key describing the attenuation factor allowing to adapt the dynamics of the output to the actual listening requirements. See KEY_AAC_DRC_BOOST_FACTOR for a description of the role of this attenuation factor and the value range.

The default value is 127 (fully apply attenuation DRC gains).

This key is only used during decoding.

Constant Value: "aac-drc-cut-level"

KEY_AAC_DRC_BOOST_FACTOR

Added in API level 21
public static final String KEY_AAC_DRC_BOOST_FACTOR

A key describing the boost factor allowing to adapt the dynamics of the output to the actual listening requirements. This relies on DRC gain sequences that can be transmitted in the encoded bitstream to be able to reduce the dynamics of the output signal upon request. This factor enables the user to select how much of the gains are applied.

Positive gains (boost) and negative gains (attenuation, see KEY_AAC_DRC_ATTENUATION_FACTOR) can be controlled separately for a better match to different use-cases.

Typically, attenuation gains are sent for loud signal segments, and boost gains are sent for soft signal segments. If the output is listened to in a noisy environment, for example, the boost factor is used to enable the positive gains, i.e. to amplify soft signal segments beyond the noise floor. But for listening late at night, the attenuation factor is used to enable the negative gains, to prevent loud signal from surprising the listener. In applications which generally need a low dynamic range, both the boost factor and the attenuation factor are used in order to enable all DRC gains.

In order to prevent clipping, it is also recommended to apply the attenuation gains in case of a downmix and/or loudness normalization to high target reference levels.

Both the boost and the attenuation factor parameters are given as integer values between 0 and 127, representing the range of the factor of 0 (i.e. don't apply) to 1 (i.e. fully apply boost/attenuation gains respectively).

The default value is 127 (fully apply boost DRC gains).

This key is only used during decoding.

Constant Value: "aac-drc-boost-level"

KEY_AAC_DRC_EFFECT_TYPE

Added in API level 28
public static final String KEY_AAC_DRC_EFFECT_TYPE

A key describing for selecting the DRC effect type for MPEG-D DRC. The supported values are defined in ISO/IEC 23003-4:2015 and are described as follows:

ValueEffect
-1Off
0None
1Late night
2Noisy environment
3Limited playback range
4Low playback level
5Dialog enhancement
6General compression

The value -1 (Off) disables DRC processing, while loudness normalization may still be active and dependent on KEY_AAC_DRC_TARGET_REFERENCE_LEVEL.
The value 0 (None) automatically enables DRC processing if necessary to prevent signal clipping
The value 6 (General compression) can be used for enabling MPEG-D DRC without particular DRC effect type request.
The default DRC effect type is 3 ("Limited playback range") on mobile devices.

This key is only used during decoding.

Constant Value: "aac-drc-effect-type"

KEY_AAC_DRC_HEAVY_COMPRESSION

Added in API level 21
public static final String KEY_AAC_DRC_HEAVY_COMPRESSION

A key describing the selection of the heavy compression profile for MPEG-4 DRC.

Two separate DRC gain sequences can be transmitted in one bitstream: light compression and heavy compression. When selecting the application of the heavy compression, one of the sequences is selected:

  • 0 enables light compression,
  • 1 enables heavy compression instead.
Note that heavy compression doesn't offer the features of scaling of DRC gains (see KEY_AAC_DRC_BOOST_FACTOR and KEY_AAC_DRC_ATTENUATION_FACTOR for the boost and attenuation factors), and frequency-selective (multiband) DRC. Light compression usually contains clipping prevention for stereo downmixing while heavy compression, if additionally provided in the bitstream, is usually stronger, and contains clipping prevention for stereo and mono downmixing.

The default is 1 (heavy compression).

This key is only used during decoding.

Constant Value: "aac-drc-heavy-compression"

KEY_AAC_DRC_OUTPUT_LOUDNESS

Added in API level 30
public static final String KEY_AAC_DRC_OUTPUT_LOUDNESS

A key to retrieve the output loudness of a decoded bitstream.

If loudness normalization is active, the value corresponds to the Target Reference Level (see KEY_AAC_DRC_TARGET_REFERENCE_LEVEL).
If loudness normalization is not active, the value corresponds to the loudness metadata given in the bitstream.

The value is retrieved with getInteger() and is given as an integer value between 0 and 231. It is calculated as -4 * Output Loudness in LKFS. Therefore, it represents the range of 0 to -57.75 LKFS.

A value of -1 indicates that no loudness metadata is present in the bitstream.

Loudness metadata can originate from MPEG-4 DRC or MPEG-D DRC.

This key is only used during decoding.

Constant Value: "aac-drc-output-loudness"

KEY_AAC_DRC_TARGET_REFERENCE_LEVEL

Added in API level 21
public static final String KEY_AAC_DRC_TARGET_REFERENCE_LEVEL

A key describing the Target Reference Level (Target Loudness).

For normalizing loudness across program items, a gain is applied to the audio output so that the output loudness matches the Target Reference Level. The gain is derived as the difference between the Target Reference Level and the Program Reference Level (Program Loudness). The latter can be given in the bitstream and indicates the actual loudness value of the program item.

The Target Reference Level controls loudness normalization for both MPEG-4 DRC and MPEG-D DRC.

The value is given as an integer value between 40 and 127, and is calculated as -4 * Target Reference Level in LKFS. Therefore, it represents the range of -10 to -31.75 LKFS.

For MPEG-4 DRC, a value of -1 switches off loudness normalization and DRC processing.

For MPEG-D DRC, a value of -1 switches off loudness normalization only. For DRC processing options of MPEG-D DRC, see KEY_AAC_DRC_EFFECT_TYPE

The default value on mobile devices is 64 (-16 LKFS).

This key is only used during decoding.

Constant Value: "aac-target-ref-level"

KEY_AAC_ENCODED_TARGET_LEVEL

Added in API level 21
public static final String KEY_AAC_ENCODED_TARGET_LEVEL

A key describing the target reference level that was assumed at the encoder for calculation of attenuation gains for clipping prevention.

If it is known, this information can be provided as an integer value between 0 and 127, which is calculated as -4 * Encoded Target Level in LKFS. If the Encoded Target Level is unknown, the value can be set to -1.

The default value is -1 (unknown).

The value is ignored when heavy compression (see KEY_AAC_DRC_HEAVY_COMPRESSION) or MPEG-D DRC is used.

This key is only used during decoding.

Constant Value: "aac-encoded-target-level"

KEY_AAC_MAX_OUTPUT_CHANNEL_COUNT

Added in API level 21
Deprecated in API level 33
public static final String KEY_AAC_MAX_OUTPUT_CHANNEL_COUNT

This constant was deprecated in API level 33.
Use the non-AAC-specific key KEY_MAX_OUTPUT_CHANNEL_COUNT instead

A key describing the maximum number of channels that can be output by the AAC decoder. By default, the decoder will output the same number of channels as present in the encoded stream, if supported. Set this value to limit the number of output channels, and use the downmix information in the stream, if available.

Values larger than the number of channels in the content to decode behave just like the actual channel count of the content (e.g. passing 99 for the decoding of 5.1 content will behave like using 6).

This key is only used during decoding.

Constant Value: "aac-max-output-channel_count"

KEY_AAC_PROFILE

Added in API level 16
public static final String KEY_AAC_PROFILE

A key describing the AAC profile to be used (AAC audio formats only). Constants are declared in MediaCodecInfo.CodecProfileLevel.

Constant Value: "aac-profile"

KEY_AAC_SBR_MODE

Added in API level 21
public static final String KEY_AAC_SBR_MODE

A key describing the AAC SBR mode to be used (AAC audio formats only). The associated value is an integer and can be set to following values:

  • 0 - no SBR should be applied
  • 1 - single rate SBR
  • 2 - double rate SBR
Note: If this key is not defined the default SRB mode for the desired AAC profile will be used.

This key is only used during encoding.

Constant Value: "aac-sbr-mode"

KEY_ALLOW_FRAME_DROP

Added in API level 31
public static final String KEY_ALLOW_FRAME_DROP

A key for applications to opt out of allowing a Surface to discard undisplayed/unconsumed frames as means to catch up after falling behind. This value is an integer. The value 0 indicates the surface is not allowed to drop frames. The value 1 indicates the surface is allowed to drop frames. MediaCodec describes the semantics.

Constant Value: "allow-frame-drop"

KEY_AUDIO_SESSION_ID

Added in API level 21
public static final String KEY_AUDIO_SESSION_ID

A key describing the audio session ID of the AudioTrack associated to a tunneled video codec. The associated value is an integer.

Constant Value: "audio-session-id"

KEY_BITRATE_MODE

Added in API level 21
public static final String KEY_BITRATE_MODE

A key describing the desired bitrate mode to be used by an encoder. Constants are declared in MediaCodecInfo.EncoderCapabilities.

Constant Value: "bitrate-mode"

KEY_BIT_RATE

Added in API level 16
public static final String KEY_BIT_RATE

A key describing the average bitrate in bits/sec. The associated value is an integer

Constant Value: "bitrate"

KEY_CAPTION_SERVICE_NUMBER

Added in API level 30
public static final String KEY_CAPTION_SERVICE_NUMBER

A key describing the closed caption service number. For CEA-608 caption tracks, holds the channel number. For CEA-708, holds the service number. The associated value is an int.

Constant Value: "caption-service-number"

KEY_CAPTURE_RATE

Added in API level 21
public static final String KEY_CAPTURE_RATE

A key describing the capture rate of a video format in frames/sec.

When capture rate is different than the frame rate, it means that the video is acquired at a different rate than the playback, which produces slow motion or timelapse effect during playback. Application can use the value of this key to tell the relative speed ratio between capture and playback rates when the video was recorded.

The associated value is an integer or a float.

Constant Value: "capture-rate"

KEY_CHANNEL_COUNT

Added in API level 16
public static final String KEY_CHANNEL_COUNT

A key describing the number of channels in an audio format. The associated value is an integer

Constant Value: "channel-count"

KEY_CHANNEL_MASK

Added in API level 16
public static final String KEY_CHANNEL_MASK

A key describing the channel composition of audio content. This mask is composed of bits drawn from channel mask definitions in AudioFormat. The associated value is an integer.

Constant Value: "channel-mask"

KEY_CODECS_STRING

Added in API level 30
public static final String KEY_CODECS_STRING

A key describing the codecs string of the MediaFormat. See RFC 6381 section 3.2 for the syntax of the value. The value does not hold MediaCodec-exposed codec names. The associated value is a string.

Constant Value: "codecs-string"

KEY_COLOR_FORMAT

Added in API level 16
public static final String KEY_COLOR_FORMAT

A key describing the color format of the content in a video format. Constants are declared in MediaCodecInfo.CodecCapabilities.

Constant Value: "color-format"

KEY_COLOR_RANGE

Added in API level 24
public static final String KEY_COLOR_RANGE

An optional key describing the range of the component values of the video content. The associated value is an integer: 0 if unspecified, or one of the COLOR_RANGE_ values.

Constant Value: "color-range"

KEY_COLOR_STANDARD

Added in API level 24
public static final String KEY_COLOR_STANDARD

An optional key describing the color primaries, white point and luminance factors for video content. The associated value is an integer: 0 if unspecified, or one of the COLOR_STANDARD_ values.

Constant Value: "color-standard"

KEY_COLOR_TRANSFER

Added in API level 24
public static final String KEY_COLOR_TRANSFER

An optional key describing the opto-electronic transfer function used for the video content. The associated value is an integer: 0 if unspecified, or one of the COLOR_TRANSFER_ values.

Constant Value: "color-transfer"

KEY_COLOR_TRANSFER_REQUEST

Added in API level 31
public static final String KEY_COLOR_TRANSFER_REQUEST

An optional key describing the opto-electronic transfer function requested for the output video content. The associated value is an integer: 0 if unspecified, or one of the COLOR_TRANSFER_ values. When unspecified the component will not touch the video content; otherwise the component will tone-map the raw video frame to match the requested transfer function. After configure, component's input format will contain this key to note whether the request is supported or not. If the value in the input format is the same as the requested value, the request is supported. The value is set to 0 if unsupported.

Constant Value: "color-transfer-request"

KEY_COMPLEXITY

Added in API level 21
public static final String KEY_COMPLEXITY

A key describing the encoding complexity. The associated value is an integer. These values are device and codec specific, but lower values generally result in faster and/or less power-hungry encoding.

Constant Value: "complexity"

KEY_CREATE_INPUT_SURFACE_SUSPENDED

Added in API level 29
public static final String KEY_CREATE_INPUT_SURFACE_SUSPENDED

If specified when configuring a video encoder that's in "surface-input" mode, it will instruct the encoder to put the surface source in suspended state when it's connected. No video frames will be accepted until a resume operation (see MediaCodec#PARAMETER_KEY_SUSPEND), optionally with timestamp specified via MediaCodec#PARAMETER_KEY_SUSPEND_TIME, is received. The value is an integer, with 1 indicating to create with the surface source suspended, or 0 otherwise. The default value is 0. If this key is not set or set to 0, the surface source will accept buffers as soon as it's connected to the encoder (although they may not be encoded immediately). This key can be used when the client wants to prepare the encoder session in advance, but do not want to accept buffers immediately.

Constant Value: "create-input-buffers-suspended"

KEY_CROP_BOTTOM

Added in API level 33
public static final String KEY_CROP_BOTTOM

A key describing the bottom-coordinate (y) of the crop rectangle. This is the bottom-most row included in the crop frame, where row indices start at 0. Additional information on the crop rectangle semantics can be found at MediaCodec.

Constant Value: "crop-bottom"

KEY_CROP_LEFT

Added in API level 33
public static final String KEY_CROP_LEFT

A key describing the left-coordinate (x) of the crop rectangle. This is the left-most column included in the crop frame, where column indices start at 0. Additional information on the crop rectangle semantics can be found at MediaCodec.

Constant Value: "crop-left"

KEY_CROP_RIGHT

Added in API level 33
public static final String KEY_CROP_RIGHT

A key describing the right-coordinate (x) of the crop rectangle. This is the right-most column included in the crop frame, where column indices start at 0. Additional information on the crop rectangle semantics can be found at MediaCodec.

Constant Value: "crop-right"

KEY_CROP_TOP

Added in API level 33
public static final String KEY_CROP_TOP

A key describing the top-coordinate (y) of the crop rectangle. This is the top-most row included in the crop frame, where row indices start at 0. Additional information on the crop rectangle semantics can be found at MediaCodec.

Constant Value: "crop-top"

KEY_DURATION

Added in API level 16
public static final String KEY_DURATION

A key describing the duration (in microseconds) of the content. The associated value is a long.

Constant Value: "durationUs"

KEY_ENCODER_DELAY

Added in API level 30
public static final String KEY_ENCODER_DELAY

A key describing the number of frames to trim from the start of the decoded audio stream. The associated value is an integer.

Constant Value: "encoder-delay"

KEY_ENCODER_PADDING

Added in API level 30
public static final String KEY_ENCODER_PADDING

A key describing the number of frames to trim from the end of the decoded audio stream. The associated value is an integer.

Constant Value: "encoder-padding"

KEY_FLAC_COMPRESSION_LEVEL

Added in API level 16
public static final String KEY_FLAC_COMPRESSION_LEVEL

A key describing the FLAC compression level to be used (FLAC audio format only). The associated value is an integer ranging from 0 (fastest, least compression) to 8 (slowest, most compression).

Constant Value: "flac-compression-level"

KEY_FRAME_RATE

Added in API level 16
public static final String KEY_FRAME_RATE

A key describing the frame rate of a video format in frames/sec.

The associated value is normally an integer when the value is used by the platform, but video codecs also accept float configuration values. Specifically, MediaExtractor provides an integer value corresponding to the frame rate information of the track if specified and non-zero. Otherwise, this key is not present. MediaCodec accepts both float and integer values.

This represents the desired operating frame rate if the KEY_OPERATING_RATE is not present and KEY_PRIORITY is 0 (realtime). Otherwise, this is just informational.

For video encoders this value corresponds to the intended frame rate (the rate at which the application intends to send frames to the encoder, as calculated by the buffer timestamps, and not from the actual real-time rate that the frames are sent to the encoder). Encoders use this hint for rate control, specifically for the initial frames, as encoders are expected to support variable frame rate (for rate control) based on the actual buffer timestamps of subsequent frames.

This key is not used in the MediaCodec input/output formats, nor by MediaMuxer.

Constant Value: "frame-rate"

KEY_GRID_COLUMNS

Added in API level 28
public static final String KEY_GRID_COLUMNS

A key describing the number of grid columns in the content in a MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF track. The associated value is an integer. Refer to MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF on decoding instructions of such tracks.

Constant Value: "grid-cols"

KEY_GRID_ROWS

Added in API level 28
public static final String KEY_GRID_ROWS

A key describing the number of grid rows in the content in a MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF track. The associated value is an integer. Refer to MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF on decoding instructions of such tracks.

Constant Value: "grid-rows"

KEY_HAPTIC_CHANNEL_COUNT

Added in API level 29
public static final String KEY_HAPTIC_CHANNEL_COUNT

A key describing the number of haptic channels in an audio format. The associated value is an integer.

Constant Value: "haptic-channel-count"

KEY_HARDWARE_AV_SYNC_ID

Added in API level 30
public static final String KEY_HARDWARE_AV_SYNC_ID

A key describing the hardware AV sync id. The associated value is an integer See android.media.tv.tuner.Tuner#getAvSyncHwId.

Constant Value: "hw-av-sync-id"

KEY_HDR10_PLUS_INFO

Added in API level 29
public static final String KEY_HDR10_PLUS_INFO

An optional key describing the HDR10+ metadata of the video content. The associated value is a ByteBuffer containing HDR10+ metadata conforming to the user_data_registered_itu_t_t35() syntax of SEI message for ST 2094-40. This key will be present on:

- The formats of output buffers of a decoder configured for HDR10+ profiles (such as MediaCodecInfo.CodecProfileLevel#VP9Profile2HDR10Plus, MediaCodecInfo.CodecProfileLevel.VP9Profile3HDR10Plus or MediaCodecInfo.CodecProfileLevel.HEVCProfileMain10HDR10Plus), or

- The formats of output buffers of an encoder configured for an HDR10+ profiles that uses out-of-band metadata (such as MediaCodecInfo.CodecProfileLevel.VP9Profile2HDR10Plus or MediaCodecInfo.CodecProfileLevel.VP9Profile3HDR10Plus).

Constant Value: "hdr10-plus-info"

KEY_HDR_STATIC_INFO

Added in API level 24
public static final String KEY_HDR_STATIC_INFO

An optional key describing the static metadata of HDR (high-dynamic-range) video content. The associated value is a ByteBuffer. This buffer contains the raw contents of the Static Metadata Descriptor (including the descriptor ID) of an HDMI Dynamic Range and Mastering InfoFrame as defined by CTA-861.3. This key must be provided to video decoders for HDR video content unless this information is contained in the bitstream and the video decoder supports an HDR-capable profile. This key must be provided to video encoders for HDR video content.

Constant Value: "hdr-static-info"

KEY_HEIGHT

Added in API level 16
public static final String KEY_HEIGHT

A key describing the height of the content in a video format. The associated value is an integer

Constant Value: "height"

KEY_INTRA_REFRESH_PERIOD

Added in API level 24
public static final String KEY_INTRA_REFRESH_PERIOD

An optional key describing the period of intra refresh in frames. This is an optional parameter that applies only to video encoders. If encoder supports it (MediaCodecInfo.CodecCapabilities#FEATURE_IntraRefresh), the whole frame is completely refreshed after the specified period. Also for each frame, a fix subset of macroblocks must be intra coded which leads to more constant bitrate than inserting a key frame. This key is recommended for video streaming applications as it provides low-delay and good error-resilience. This key is ignored if the video encoder does not support the intra refresh feature. Use the output format to verify that this feature was enabled. The associated value is an integer.

Constant Value: "intra-refresh-period"

KEY_IS_ADTS

Added in API level 16
public static final String KEY_IS_ADTS

A key mapping to a value of 1 if the content is AAC audio and audio frames are prefixed with an ADTS header. The associated value is an integer (0 or 1). This key is only supported when _decoding_ content, it cannot be used to configure an encoder to emit ADTS output.

Constant Value: "is-adts"

KEY_IS_AUTOSELECT

Added in API level 19
public static final String KEY_IS_AUTOSELECT

A key for boolean AUTOSELECT behavior for the track. Tracks with AUTOSELECT=true are considered when automatically selecting a track without specific user choice, based on the current locale. This is currently only used for subtitle tracks, when the user selected 'Default' for the captioning locale. The associated value is an integer, where non-0 means TRUE. This is an optional field; if not specified, AUTOSELECT defaults to TRUE.

Constant Value: "is-autoselect"

KEY_IS_DEFAULT

Added in API level 19
public static final String KEY_IS_DEFAULT

A key for boolean DEFAULT behavior for the track. The track with DEFAULT=true is selected in the absence of a specific user choice. This is currently used in two scenarios: 1) for subtitle tracks, when the user selected 'Default' for the captioning locale. 2) for a MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF track, indicating the image is the primary item in the file. The associated value is an integer, where non-0 means TRUE. This is an optional field; if not specified, DEFAULT is considered to be FALSE.

Constant Value: "is-default"

KEY_IS_FORCED_SUBTITLE

Added in API level 19
public static final String KEY_IS_FORCED_SUBTITLE

A key for the FORCED field for subtitle tracks. True if it is a forced subtitle track. Forced subtitle tracks are essential for the content and are shown even when the user turns off Captions. They are used for example to translate foreign/alien dialogs or signs. The associated value is an integer, where non-0 means TRUE. This is an optional field; if not specified, FORCED defaults to FALSE.

Constant Value: "is-forced-subtitle"

KEY_I_FRAME_INTERVAL

Added in API level 16
public static final String KEY_I_FRAME_INTERVAL

A key describing the frequency of key frames expressed in seconds between key frames.

This key is used by video encoders. A negative value means no key frames are requested after the first frame. A zero value means a stream containing all key frames is requested.

Most video encoders will convert this value of the number of non-key-frames between key-frames, using the frame rate information; therefore, if the actual frame rate differs (e.g. input frames are dropped or the frame rate changes), the time interval between key frames will not be the configured value.

The associated value is an integer (or float since Build.VERSION_CODES.N_MR1).

Constant Value: "i-frame-interval"

KEY_LANGUAGE

Added in API level 19
public static final String KEY_LANGUAGE

A key describing the language of the content, using either ISO 639-1 or 639-2/T codes. The associated value is a string.

Constant Value: "language"

KEY_LATENCY

Added in API level 26
public static final String KEY_LATENCY

An optional key describing the desired encoder latency in frames. This is an optional parameter that applies only to video encoders. If encoder supports it, it should ouput at least one output frame after being queued the specified number of frames. This key is ignored if the video encoder does not support the latency feature. Use the output format to verify that this feature was enabled and the actual value used by the encoder.

If the key is not specified, the default latency will be implenmentation specific. The associated value is an integer.

Constant Value: "latency"

KEY_LEVEL

Added in API level 23
public static final String KEY_LEVEL

A key describing the desired profile to be used by an encoder.

The associated value is an integer. Constants are declared in MediaCodecInfo.CodecProfileLevel. This key is used as a further hint when specifying a desired profile, and is only supported for codecs that specify a level.

This key is ignored if the profile is not specified. Otherwise, the value should be a level compatible with the configured encoding parameters.

Note: This key cannot be used to constrain the encoder's output to a maximum encoding level. Encoders are free to target a different level if the configured encoding parameters dictate it. Nevertheless, encoders shall use (and encode) a level sufficient to decode the generated bitstream, though they may exceed the (Video) Buffering Verifier limits for that encoded level.

Constant Value: "level"

KEY_LOW_LATENCY

Added in API level 30
public static final String KEY_LOW_LATENCY

An optional key describing the low latency decoding mode. This is an optional parameter that applies only to decoders. If enabled, the decoder doesn't hold input and output data more than required by the codec standards. The associated value is an integer (0 or 1): 1 when low-latency decoding is enabled, 0 otherwise. The default value is 0.

Constant Value: "low-latency"

KEY_MAX_B_FRAMES

Added in API level 29
public static final String KEY_MAX_B_FRAMES

A key describing the maximum number of B frames between I or P frames, to be used by a video encoder. The associated value is an integer. The default value is 0, which means that no B frames are allowed. Note that non-zero value does not guarantee B frames; it's up to the encoder to decide.

Constant Value: "max-bframes"

KEY_MAX_FPS_TO_ENCODER

Added in API level 29
public static final String KEY_MAX_FPS_TO_ENCODER

Instruct the video encoder in "surface-input" mode to drop excessive frames from the source, so that the input frame rate to the encoder does not exceed the specified fps. The associated value is a float, representing the max frame rate to feed the encoder at.

Constant Value: "max-fps-to-encoder"

KEY_MAX_HEIGHT

Added in API level 19
public static final String KEY_MAX_HEIGHT

A key describing the maximum expected height of the content in a video decoder format, in case there are resolution changes in the video content. The associated value is an integer

Constant Value: "max-height"

KEY_MAX_INPUT_SIZE

Added in API level 16
public static final String KEY_MAX_INPUT_SIZE

A key describing the maximum size in bytes of a buffer of data described by this MediaFormat. The associated value is an integer

Constant Value: "max-input-size"

KEY_MAX_OUTPUT_CHANNEL_COUNT

Added in API level 32
public static final String KEY_MAX_OUTPUT_CHANNEL_COUNT

A key describing the maximum number of channels that can be output by an audio decoder. By default, the decoder will output the same number of channels as present in the encoded stream, if supported. Set this value to limit the number of output channels, and use the downmix information in the stream, if available.

Values larger than the number of channels in the content to decode behave like the number of channels in the content (if applicable), for instance passing 99 for a 5.1 audio stream behaves like passing 6.

This key is only used during decoding.

Constant Value: "max-output-channel-count"

KEY_MAX_PTS_GAP_TO_ENCODER

Added in API level 29
public static final String KEY_MAX_PTS_GAP_TO_ENCODER

Instruct the video encoder in "surface-input" mode to limit the gap of timestamp between any two adjacent frames fed to the encoder to the specified amount (in micro-second). The associated value is a long int. When positive, it represents the max timestamp gap between two adjacent frames fed to the encoder. When negative, the absolute value represents a fixed timestamp gap between any two adjacent frames fed to the encoder. Note that this will also apply even when the original timestamp goes backward in time. Under normal conditions, such frames would be dropped and not sent to the encoder. The output timestamp will be restored to the original timestamp and will not be affected. This is used in some special scenarios where input frames arrive sparingly but it's undesirable to allocate more bits to any single frame, or when it's important to ensure all frames are captured (rather than captured in the correct order).

Constant Value: "max-pts-gap-to-encoder"

KEY_MAX_WIDTH

Added in API level 19
public static final String KEY_MAX_WIDTH

A key describing the maximum expected width of the content in a video decoder format, in case there are resolution changes in the video content. The associated value is an integer

Constant Value: "max-width"

KEY_MIME

Added in API level 16
public static final String KEY_MIME

A key describing the mime type of the MediaFormat. The associated value is a string.

Constant Value: "mime"

KEY_MPEGH_COMPATIBLE_SETS

Added in API level 31
public static final String KEY_MPEGH_COMPATIBLE_SETS

A key describing the MPEG-H stream compatible sets. See FDAmd_2 of ISO_IEC_23008-3;2019 MHAProfileAndLevelCompatibilitySetBox.

Constant Value: "mpegh-compatible-sets"

KEY_MPEGH_PROFILE_LEVEL_INDICATION

Added in API level 31
public static final String KEY_MPEGH_PROFILE_LEVEL_INDICATION

A key describing the MPEG-H stream profile-level indication. See ISO_IEC_23008-3;2019 MHADecoderConfigurationRecord mpegh3daProfileLevelIndication.

Constant Value: "mpegh-profile-level-indication"

KEY_MPEGH_REFERENCE_CHANNEL_LAYOUT

Added in API level 31
public static final String KEY_MPEGH_REFERENCE_CHANNEL_LAYOUT

A key describing the MPEG-H stream reference channel layout. See ISO_IEC_23008-3;2019 MHADecoderConfigurationRecord referenceChannelLayout and ISO_IEC_23001\u20108 ChannelConfiguration value.

Constant Value: "mpegh-reference-channel-layout"

KEY_OPERATING_RATE

Added in API level 23
public static final String KEY_OPERATING_RATE

A key describing the desired operating frame rate for video or sample rate for audio that the codec will need to operate at.

The associated value is an integer or a float representing frames-per-second or samples-per-second

This is used for cases like high-speed/slow-motion video capture, where the video encoder format contains the target playback rate (e.g. 30fps), but the component must be able to handle the high operating capture rate (e.g. 240fps).

This rate will be used by codec for resource planning and setting the operating points.

Constant Value: "operating-rate"

KEY_OUTPUT_REORDER_DEPTH

Added in API level 28
public static final String KEY_OUTPUT_REORDER_DEPTH

An optional key describing the maximum number of non-display-order coded frames. This is an optional parameter that applies only to video encoders. Application should check the value for this key in the output format to see if codec will produce non-display-order coded frames. If encoder supports it, the output frames' order will be different from the display order and each frame's display order could be retrived from MediaCodec.BufferInfo#presentationTimeUs. Before API level 27, application may receive non-display-order coded frames even though the application did not request it. Note: Application should not rearrange the frames to display order before feeding them to MediaMuxer#writeSampleData.

The default value is 0.

Constant Value: "output-reorder-depth"

KEY_PCM_ENCODING

Added in API level 24
public static final String KEY_PCM_ENCODING

A key describing the raw audio sample encoding/format.

The associated value is an integer, using one of the AudioFormat.ENCODING_PCM_ values.

This is an optional key for audio decoders and encoders specifying the desired raw audio sample format during MediaCodec.configure(…) call. Use MediaCodec.getInput/OutputFormat(…) to confirm the actual format. For the PCM decoder this key specifies both input and output sample encodings.

This key is also used by MediaExtractor to specify the sample format of audio data, if it is specified.

If this key is missing, the raw audio sample format is signed 16-bit short.

Constant Value: "pcm-encoding"

KEY_PICTURE_TYPE

Added in API level 33
public static final String KEY_PICTURE_TYPE

A key describing the picture type of the encoded frame. This is a part of a video 'Encoding Statistics' export feature. This value is emitted from video encoder for a video frame. The associated value is an integer.

Constant Value: "picture-type"

KEY_PIXEL_ASPECT_RATIO_HEIGHT

Added in API level 30
public static final String KEY_PIXEL_ASPECT_RATIO_HEIGHT

A key describing the pixel aspect ratio height. The associated value is an integer

Constant Value: "sar-height"

KEY_PIXEL_ASPECT_RATIO_WIDTH

Added in API level 30
public static final String KEY_PIXEL_ASPECT_RATIO_WIDTH

A key describing the pixel aspect ratio width. The associated value is an integer

Constant Value: "sar-width"

KEY_PREPEND_HEADER_TO_SYNC_FRAMES

Added in API level 29
public static final String KEY_PREPEND_HEADER_TO_SYNC_FRAMES

An optional key describing whether encoders prepend headers to sync frames (e.g. SPS and PPS to IDR frames for H.264). This is an optional parameter that applies only to video encoders. A video encoder may not support this feature; the component will fail to configure in that case. For other components, this key is ignored. The value is an integer, with 1 indicating to prepend headers to every sync frames, or 0 otherwise. The default value is 0.

Constant Value: "prepend-sps-pps-to-idr-frames"

KEY_PRIORITY

Added in API level 23
public static final String KEY_PRIORITY

A key describing the desired codec priority.

The associated value is an integer. Higher value means lower priority.

Currently, only two levels are supported:
0: realtime priority - meaning that the codec shall support the given performance configuration (e.g. framerate) at realtime. This should only be used by media playback, capture, and possibly by realtime communication scenarios if best effort performance is not suitable.
1: non-realtime priority (best effort).

This is a hint used at codec configuration and resource planning - to understand the realtime requirements of the application; however, due to the nature of media components, performance is not guaranteed.

Constant Value: "priority"

KEY_PROFILE

Added in API level 21
public static final String KEY_PROFILE

A key describing the desired profile to be used by an encoder.

The associated value is an integer. Constants are declared in MediaCodecInfo.CodecProfileLevel. This key is used as a hint, and is only supported for codecs that specify a profile. When configuring profile, encoder configuration may fail if other parameters are not compatible with the desired profile or if the desired profile is not supported, but it may also fail silently (where the encoder ends up using a different, compatible profile.)

It is recommended that the profile is set for all encoders. For more information, see the Encoder Profiles section of the MediaCodec API reference.

Note: Codecs are free to use all the available coding tools at the specified profile, but may ultimately choose to not do so.

Note: When configuring video encoders, profile (if set) must be set together with level.

Constant Value: "profile"

KEY_PUSH_BLANK_BUFFERS_ON_STOP

Added in API level 19
public static final String KEY_PUSH_BLANK_BUFFERS_ON_STOP

If specified when configuring a video decoder rendering to a surface, causes the decoder to output "blank", i.e. black frames to the surface when stopped to clear out any previously displayed contents. The associated value is an integer of value 1.

Constant Value: "push-blank-buffers-on-shutdown"

KEY_QUALITY

Added in API level 28
public static final String KEY_QUALITY

A key describing the desired encoding quality. The associated value is an integer. This key is only supported for encoders that are configured in constant-quality mode. These values are device and codec specific, but lower values generally result in more efficient (smaller-sized) encoding.

Constant Value: "quality"

KEY_REPEAT_PREVIOUS_FRAME_AFTER

Added in API level 19
public static final String KEY_REPEAT_PREVIOUS_FRAME_AFTER

Applies only when configuring a video encoder in "surface-input" mode. The associated value is a long and gives the time in microseconds after which the frame previously submitted to the encoder will be repeated (once) if no new frame became available since.

Constant Value: "repeat-previous-frame-after"

KEY_ROTATION

Added in API level 23
public static final String KEY_ROTATION

A key describing the desired clockwise rotation on an output surface. This key is only used when the codec is configured using an output surface. The associated value is an integer, representing degrees. Supported values are 0, 90, 180 or 270. This is an optional field; if not specified, rotation defaults to 0.

Constant Value: "rotation-degrees"

KEY_SAMPLE_RATE

Added in API level 16
public static final String KEY_SAMPLE_RATE

A key describing the sample rate of an audio format. The associated value is an integer

Constant Value: "sample-rate"

KEY_SLICE_HEIGHT

Added in API level 23
public static final String KEY_SLICE_HEIGHT

A key describing the plane height of a multi-planar (YUV) video bytebuffer layout. Slice height (or plane height/vertical stride) is the number of rows that must be skipped to get from the top of the Y plane to the top of the U plane in the bytebuffer. In essence the offset of the U plane is sliceHeight * stride. The height of the U/V planes can be calculated based on the color format, though it is generally undefined and depends on the device and release. The associated value is an integer, representing number of rows.

Constant Value: "slice-height"

KEY_SLOW_MOTION_MARKERS

Added in API level 31
public static final String KEY_SLOW_MOTION_MARKERS

A key for retrieving the slow-motion marker information associated with a video track.

The associated value is a ByteBuffer in ByteOrder#BIG_ENDIAN (networking order) of the following format:

     float(32) playbackRate;
     unsigned int(32) numMarkers;
     for (i = 0;i < numMarkers; i++) {
         int(64) timestampUs;
         float(32) speedRatio;
     }
The meaning of each field is as follows:
playbackRate The frame rate at which the playback should happen (or the flattened clip should be).
numMarkers The number of slow-motion markers that follows.
timestampUs The starting point of a new segment.
speedRatio The playback speed for that segment. The playback speed is a floating point number, indicating how fast the time progresses relative to that written in the container. (Eg. 4.0 means time goes 4x as fast, which makes 30fps become 120fps.)

The following constraints apply to the timestampUs of the markers:

  • The timestampUs shall be monotonically increasing.
  • The timestampUs shall fall within the time span of the video track.
  • The first timestampUs should match that of the first video sample.
  • Constant Value: "slow-motion-markers"

    KEY_STRIDE

    Added in API level 23
    public static final String KEY_STRIDE

    A key describing the stride of the video bytebuffer layout. Stride (or row increment) is the difference between the index of a pixel and that of the pixel directly underneath. For YUV 420 formats, the stride corresponds to the Y plane; the stride of the U and V planes can be calculated based on the color format, though it is generally undefined and depends on the device and release. The associated value is an integer, representing number of bytes.

    Constant Value: "stride"

    KEY_TEMPORAL_LAYERING

    Added in API level 21
    public static final String KEY_TEMPORAL_LAYERING

    A key describing the temporal layering schema. This is an optional parameter that applies only to video encoders. Use MediaCodec#getOutputFormat after configure to query if the encoder supports the desired schema. Supported values are webrtc.vp8.N-layer, android.generic.N, android.generic.N+M and none, where N denotes the total number of non-bidirectional layers (which must be at least 1) and M denotes the total number of bidirectional layers (which must be non-negative).

    android.generic.* schemas have been added in Build.VERSION_CODES.N_MR1.

    The encoder may support fewer temporal layers, in which case the output format will contain the configured schema. If the encoder does not support temporal layering, the output format will not have an entry with this key. The associated value is a string.

    Constant Value: "ts-schema"

    KEY_TILE_HEIGHT

    Added in API level 28
    public static final String KEY_TILE_HEIGHT

    A key describing the height (in pixels) of each tile of the content in a MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF track. The associated value is an integer. Refer to MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF on decoding instructions of such tracks.

    Constant Value: "tile-height"

    KEY_TILE_WIDTH

    Added in API level 28
    public static final String KEY_TILE_WIDTH

    A key describing the width (in pixels) of each tile of the content in a MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF track. The associated value is an integer. Refer to MIMETYPE_IMAGE_ANDROID_HEIC / MIMETYPE_IMAGE_AVIF on decoding instructions of such tracks.

    Constant Value: "tile-width"

    KEY_TRACK_ID

    Added in API level 24
    public static final String KEY_TRACK_ID

    A key describing a unique ID for the content of a media track.

    This key is used by MediaExtractor. Some extractors provide multiple encodings of the same track (e.g. float audio tracks for FLAC and WAV may be expressed as two tracks via MediaExtractor: a normal PCM track for backward compatibility, and a float PCM track for added fidelity. Similarly, Dolby Vision extractor may provide a baseline SDR version of a DV track.) This key can be used to identify which MediaExtractor tracks refer to the same underlying content.

    The associated value is an integer.

    Constant Value: "track-id"

    KEY_VIDEO_ENCODING_STATISTICS_LEVEL

    Added in API level 33
    public static final String KEY_VIDEO_ENCODING_STATISTICS_LEVEL

    A key describing the level of encoding statistics information emitted from video encoder. The associated value is an integer.

    Constant Value: "video-encoding-statistics-level"

    KEY_VIDEO_QP_AVERAGE

    Added in API level 33
    public static final String KEY_VIDEO_QP_AVERAGE

    A key describing the per-frame average block QP (Quantization Parameter). This is a part of a video 'Encoding Statistics' export feature. This value is emitted from video encoder for a video frame. The average value is rounded to the nearest integer value. The associated value is an integer.

    Constant Value: "video-qp-average"

    KEY_VIDEO_QP_B_MAX

    Added in API level 31
    public static final String KEY_VIDEO_QP_B_MAX

    A key describing the maximum Quantization Parameter allowed for encoding video. This value applies to video B-frames. The associated value is an integer.

    Constant Value: "video-qp-b-max"

    KEY_VIDEO_QP_B_MIN

    Added in API level 31
    public static final String KEY_VIDEO_QP_B_MIN

    A key describing the minimum Quantization Parameter allowed for encoding video. This value applies to video B-frames. The associated value is an integer.

    Constant Value: "video-qp-b-min"

    KEY_VIDEO_QP_I_MAX

    Added in API level 31
    public static final String KEY_VIDEO_QP_I_MAX

    A key describing the maximum Quantization Parameter allowed for encoding video. This value applies to video I-frames. The associated value is an integer.

    Constant Value: "video-qp-i-max"

    KEY_VIDEO_QP_I_MIN

    Added in API level 31
    public static final String KEY_VIDEO_QP_I_MIN

    A key describing the minimum Quantization Parameter allowed for encoding video. This value applies to video I-frames. The associated value is an integer.

    Constant Value: "video-qp-i-min"

    KEY_VIDEO_QP_MAX

    Added in API level 31
    public static final String KEY_VIDEO_QP_MAX

    A key describing the maximum Quantization Parameter allowed for encoding video. This key applies to all three video picture types (I, P, and B). The value is used directly for picture type I; a per-mime formula is used to calculate the value for the remaining picture types. This calculation can be avoided by directly specifying values for each picture type using the type-specific keys KEY_VIDEO_QP_I_MAX, KEY_VIDEO_QP_P_MAX, and KEY_VIDEO_QP_B_MAX. The associated value is an integer.

    Constant Value: "video-qp-max"

    KEY_VIDEO_QP_MIN

    Added in API level 31
    public static final String KEY_VIDEO_QP_MIN

    A key describing the minimum Quantization Parameter allowed for encoding video. This key applies to all three video frame types (I, P, and B). The value is used directly for picture type I; a per-mime formula is used to calculate the value for the remaining picture types. This calculation can be avoided by directly specifying values for each picture type using the type-specific keys KEY_VIDEO_QP_I_MIN, KEY_VIDEO_QP_P_MIN, and KEY_VIDEO_QP_B_MIN. The associated value is an integer.

    Constant Value: "video-qp-min"

    KEY_VIDEO_QP_P_MAX

    Added in API level 31
    public static final String KEY_VIDEO_QP_P_MAX

    A key describing the maximum Quantization Parameter allowed for encoding video. This value applies to video P-frames. The associated value is an integer.

    Constant Value: "video-qp-p-max"

    KEY_VIDEO_QP_P_MIN

    Added in API level 31
    public static final String KEY_VIDEO_QP_P_MIN

    A key describing the minimum Quantization Parameter allowed for encoding video. This value applies to video P-frames. The associated value is an integer.

    Constant Value: "video-qp-p-min"

    KEY_WIDTH

    Added in API level 16
    public static final String KEY_WIDTH

    A key describing the width of the content in a video format. The associated value is an integer

    Constant Value: "width"

    LOG_SESSION_ID

    Added in API level 34
    public static final String LOG_SESSION_ID

    A key describing the log session ID for MediaCodec. The log session ID is a random 32-byte hexadecimal string that is used to associate metrics from multiple media codec instances to the same playback or recording session. The value is created as LogSessionId. Sessions are created in MediaMetricsManager. The associated value is a string.

    Constant Value: "log-session-id"

    MIMETYPE_AUDIO_AAC

    Added in API level 21
    public static final String MIMETYPE_AUDIO_AAC

    Constant Value: "audio/mp4a-latm"

    MIMETYPE_AUDIO_AAC_ELD

    Added in API level 33
    public static final String MIMETYPE_AUDIO_AAC_ELD

    MIME type for AAC Enhanced Low Delay (ELD) audio stream. Uses the scheme defined by RFC 6381 with OTI of MPEG-4 (40) and AOT of ELD (39) from ISO/IEC 14496-3.

    Constant Value: "audio/mp4a.40.39"

    MIMETYPE_AUDIO_AAC_HE_V1

    Added in API level 33
    public static final String MIMETYPE_AUDIO_AAC_HE_V1

    MIME type for HE-AAC v1 (LC + SBR) audio stream. Uses the scheme defined by RFC 6381 with OTI of MPEG-4 (40) and AOT of AAC SBR (5) from ISO/IEC 14496-3.

    Constant Value: "audio/mp4a.40.05"

    MIMETYPE_AUDIO_AAC_HE_V2

    Added in API level 33
    public static final String MIMETYPE_AUDIO_AAC_HE_V2

    MIME type for HE-AAC v2 (LC + SBR + PS) audio stream. Uses the scheme defined by RFC 6381 with OTI of MPEG-4 (40) and AOT of PS (29) from ISO/IEC 14496-3.

    Constant Value: "audio/mp4a.40.29"

    MIMETYPE_AUDIO_AAC_LC

    Added in API level 33
    public static final String MIMETYPE_AUDIO_AAC_LC

    MIME type for AAC Low Complexity (LC) audio stream. Uses the scheme defined by RFC 6381 with OTI of MPEG-4 (40) and AOT of AAC LC (2) from ISO/IEC 14496-3.

    Constant Value: "audio/mp4a.40.02"

    MIMETYPE_AUDIO_AAC_XHE

    Added in API level 33
    public static final String MIMETYPE_AUDIO_AAC_XHE

    MIME type for AAC XHE audio stream. Uses the scheme defined by RFC 6381 with OTI of MPEG-4 (40) and AOT of USAC (42) from ISO/IEC 14496-3.

    Constant Value: "audio/mp4a.40.42"

    MIMETYPE_AUDIO_AC3

    Added in API level 21
    public static final String MIMETYPE_AUDIO_AC3

    Constant Value: "audio/ac3"

    MIMETYPE_AUDIO_AC4

    Added in API level 29
    public static final String MIMETYPE_AUDIO_AC4

    Constant Value: "audio/ac4"

    MIMETYPE_AUDIO_AMR_NB

    Added in API level 21
    public static final String MIMETYPE_AUDIO_AMR_NB

    Constant Value: "audio/3gpp"

    MIMETYPE_AUDIO_AMR_WB

    Added in API level 21
    public static final String MIMETYPE_AUDIO_AMR_WB

    Constant Value: "audio/amr-wb"

    MIMETYPE_AUDIO_DOLBY_MAT

    Added in API level 33
    public static final String MIMETYPE_AUDIO_DOLBY_MAT

    MIME type for Dolby Metadata-enhanced Audio Transmission (MAT) audio stream.

    Constant Value: "audio/vnd.dolby.mat"

    MIMETYPE_AUDIO_DOLBY_TRUEHD

    Added in API level 33
    public static final String MIMETYPE_AUDIO_DOLBY_TRUEHD

    MIME type for Dolby TrueHD audio format, based on Meridian Lossless Packing (MLP).

    Constant Value: "audio/vnd.dolby.mlp"

    MIMETYPE_AUDIO_DRA

    Added in API level 33
    public static final String MIMETYPE_AUDIO_DRA

    MIME type for Dynamic Resolution Adaptation (DRA) audio stream.

    Constant Value: "audio/vnd.dra"

    MIMETYPE_AUDIO_DTS

    Added in API level 33
    public static final String MIMETYPE_AUDIO_DTS

    MIME type for DTS Digital Surround (up to 5.1 channels) audio stream, aka DTS-CA.

    Constant Value: "audio/vnd.dts"

    MIMETYPE_AUDIO_DTS_HD

    Added in API level 33
    public static final String MIMETYPE_AUDIO_DTS_HD

    MIME type for DTS HD (up to 7.1 channels) audio stream. With codec profile DTS_HDProfileHRA represents DTS HD High Resolution Audio. With codec profile DTS_HDProfileMA represents DTS HD Master Audio. With codec profile DTS_HDProfileLBR represents DTS Express.

    Constant Value: "audio/vnd.dts.hd"

    MIMETYPE_AUDIO_DTS_UHD

    Added in API level 33
    public static final String MIMETYPE_AUDIO_DTS_UHD

    MIME type for DTS UHD (object-based) audio stream, aka DTS:X. With codec profile DTS_UHDProfileP1 represents DTS-UHD P1. With codec profile DTS_UHDProfileP2 represents DTS-UHD P2.

    Constant Value: "audio/vnd.dts.uhd"

    MIMETYPE_AUDIO_EAC3

    Added in API level 23
    public static final String MIMETYPE_AUDIO_EAC3

    Constant Value: "audio/eac3"

    MIMETYPE_AUDIO_EAC3_JOC

    Added in API level 29
    public static final String MIMETYPE_AUDIO_EAC3_JOC

    Constant Value: "audio/eac3-joc"

    MIMETYPE_AUDIO_FLAC

    Added in API level 21
    public static final String MIMETYPE_AUDIO_FLAC

    Constant Value: "audio/flac"

    MIMETYPE_AUDIO_G711_ALAW

    Added in API level 21
    public static final String MIMETYPE_AUDIO_G711_ALAW

    Constant Value: "audio/g711-alaw"

    MIMETYPE_AUDIO_G711_MLAW

    Added in API level 21
    public static final String MIMETYPE_AUDIO_G711_MLAW

    Constant Value: "audio/g711-mlaw"

    MIMETYPE_AUDIO_IEC61937

    Added in API level 33
    public static final String MIMETYPE_AUDIO_IEC61937

    MIME type for the IEC61937 audio stream encapsulation. This type isn't defined by IANA.

    Constant Value: "audio/x-iec61937"

    MIMETYPE_AUDIO_MPEG

    Added in API level 21
    public static final String MIMETYPE_AUDIO_MPEG

    Constant Value: "audio/mpeg"

    MIMETYPE_AUDIO_MPEGH_BL_L3

    Added in API level 33
    public static final String MIMETYPE_AUDIO_MPEGH_BL_L3

    MIME type for MPEG-H Baseline (BL) Profile L3 audio stream. Uses the scheme defined by RFC 6381 with mpegh3daProfileLevelIndication for main profile/L3 (0x3) from ISO/IEC 23008-3.

    Constant Value: "audio/mhm1.03"

    MIMETYPE_AUDIO_MPEGH_BL_L4

    Added in API level 33
    public static final String MIMETYPE_AUDIO_MPEGH_BL_L4

    MIME type for MPEG-H Baseline (BL) Profile L4 audio stream. Uses the scheme defined by RFC 6381 with mpegh3daProfileLevelIndication for main profile/L4 (0x4) from ISO/IEC 23008-3.

    Constant Value: "audio/mhm1.04"

    MIMETYPE_AUDIO_MPEGH_LC_L3

    Added in API level 33
    public static final String MIMETYPE_AUDIO_MPEGH_LC_L3

    MIME type for MPEG-H Low Complexity (LC) L3 audio stream. Uses the scheme defined by RFC 6381 with mpegh3daProfileLevelIndication for LC profile/L3 (0xD) from ISO/IEC 23008-3.

    Constant Value: "audio/mhm1.0d"

    MIMETYPE_AUDIO_MPEGH_LC_L4

    Added in API level 33
    public static final String MIMETYPE_AUDIO_MPEGH_LC_L4

    MIME type for MPEG-H Low Complexity (LC) L4 audio stream. Uses the scheme defined by RFC 6381 with mpegh3daProfileLevelIndication for LC profile/L4 (0xE) from ISO/IEC 23008-3.

    Constant Value: "audio/mhm1.0e"

    MIMETYPE_AUDIO_MPEGH_MHA1

    Added in API level 31
    public static final String MIMETYPE_AUDIO_MPEGH_MHA1

    MIME type for MPEG-H Audio single stream

    Constant Value: "audio/mha1"

    MIMETYPE_AUDIO_MPEGH_MHM1

    Added in API level 31
    public static final String MIMETYPE_AUDIO_MPEGH_MHM1

    MIME type for MPEG-H Audio single stream, encapsulated in MHAS

    Constant Value: "audio/mhm1"

    MIMETYPE_AUDIO_MSGSM

    Added in API level 21
    public static final String MIMETYPE_AUDIO_MSGSM

    Constant Value: "audio/gsm"

    MIMETYPE_AUDIO_OPUS

    Added in API level 21
    public static final String MIMETYPE_AUDIO_OPUS

    Constant Value: "audio/opus"

    MIMETYPE_AUDIO_QCELP

    Added in API level 21
    public static final String MIMETYPE_AUDIO_QCELP

    Constant Value: "audio/qcelp"

    MIMETYPE_AUDIO_RAW

    Added in API level 21
    public static final String MIMETYPE_AUDIO_RAW

    Constant Value: "audio/raw"

    MIMETYPE_AUDIO_SCRAMBLED

    Added in API level 26
    public static final String MIMETYPE_AUDIO_SCRAMBLED

    Constant Value: "audio/scrambled"

    MIMETYPE_AUDIO_VORBIS

    Added in API level 21
    public static final String MIMETYPE_AUDIO_VORBIS

    Constant Value: "audio/vorbis"

    MIMETYPE_IMAGE_ANDROID_HEIC

    Added in API level 28
    public static final String MIMETYPE_IMAGE_ANDROID_HEIC

    MIME type for HEIF still image data encoded in HEVC. To decode such an image, MediaCodec decoder for MIMETYPE_VIDEO_HEVC shall be used. The client needs to form the correct MediaFormat() based on additional information in the track format (shown in the next paragraph), and send it to MediaCodec#configure. The track's MediaFormat will come with KEY_WIDTH and KEY_HEIGHT keys, which describes the width and height of the image. If the image doesn't contain grid (i.e. none of KEY_TILE_WIDTH, KEY_TILE_HEIGHT, KEY_GRID_ROWS, KEY_GRID_COLUMNS are present), the track will contain a single sample of coded data for the entire image, and the image width and height should be used to set up the decoder. If the image does come with grid, each sample from the track will contain one tile in the grid, of which the size is described by KEY_TILE_WIDTH and KEY_TILE_HEIGHT. This size (instead of KEY_WIDTH and KEY_HEIGHT) should be used to set up the decoder. The track contains KEY_GRID_ROWS by KEY_GRID_COLUMNS samples in row-major, top-row first, left-to-right order. The output image should be reconstructed by first tiling the decoding results of the tiles in the correct order, then trimming (before rotation is applied) on the bottom and right side, if the tiled area is larger than the image width and height.

    Constant Value: "image/vnd.android.heic"

    MIMETYPE_IMAGE_AVIF

    Added in API level 34
    public static final String MIMETYPE_IMAGE_AVIF

    MIME type for AVIF still image data encoded in AV1. To decode such an image, MediaCodec decoder for MIMETYPE_VIDEO_AV1 shall be used. The client needs to form the correct MediaFormat() based on additional information in the track format (shown in the next paragraph), and send it to MediaCodec#configure. The track's MediaFormat will come with KEY_WIDTH and KEY_HEIGHT keys, which describes the width and height of the image. If the image doesn't contain grid (i.e. none of KEY_TILE_WIDTH, KEY_TILE_HEIGHT, KEY_GRID_ROWS, KEY_GRID_COLUMNS are present), the track will contain a single sample of coded data for the entire image, and the image width and height should be used to set up the decoder. If the image does come with grid, each sample from the track will contain one tile in the grid, of which the size is described by KEY_TILE_WIDTH and KEY_TILE_HEIGHT. This size (instead of KEY_WIDTH and KEY_HEIGHT) should be used to set up the decoder. The track contains KEY_GRID_ROWS by KEY_GRID_COLUMNS samples in row-major, top-row first, left-to-right order. The output image should be reconstructed by first tiling the decoding results of the tiles in the correct order, then trimming (before rotation is applied) on the bottom and right side, if the tiled area is larger than the image width and height.

    Constant Value: "image/avif"

    MIMETYPE_TEXT_CEA_608

    Added in API level 21
    public static final String MIMETYPE_TEXT_CEA_608

    MIME type for CEA-608 closed caption data.

    Constant Value: "text/cea-608"

    MIMETYPE_TEXT_CEA_708

    Added in API level 28
    public static final String MIMETYPE_TEXT_CEA_708

    MIME type for CEA-708 closed caption data.

    Constant Value: "text/cea-708"

    MIMETYPE_TEXT_SUBRIP

    Added in API level 28
    public static final String MIMETYPE_TEXT_SUBRIP

    MIME type for SubRip (SRT) container.

    Constant Value: "application/x-subrip"

    MIMETYPE_TEXT_VTT

    Added in API level 21
    public static final String MIMETYPE_TEXT_VTT

    MIME type for WebVTT subtitle data.

    Constant Value: "text/vtt"

    MIMETYPE_VIDEO_AV1

    Added in API level 29
    public static final String MIMETYPE_VIDEO_AV1

    Constant Value: "video/av01"

    MIMETYPE_VIDEO_AVC

    Added in API level 21
    public static final String MIMETYPE_VIDEO_AVC

    Constant Value: "video/avc"

    MIMETYPE_VIDEO_DOLBY_VISION

    Added in API level 24
    public static final String MIMETYPE_VIDEO_DOLBY_VISION

    Constant Value: "video/dolby-vision"

    MIMETYPE_VIDEO_H263

    Added in API level 21
    public static final String MIMETYPE_VIDEO_H263

    Constant Value: "video/3gpp"

    MIMETYPE_VIDEO_HEVC

    Added in API level 21
    public static final String MIMETYPE_VIDEO_HEVC

    Constant Value: "video/hevc"

    MIMETYPE_VIDEO_MPEG2

    Added in API level 21
    public static final String MIMETYPE_VIDEO_MPEG2

    Constant Value: "video/mpeg2"

    MIMETYPE_VIDEO_MPEG4

    Added in API level 21
    public static final String MIMETYPE_VIDEO_MPEG4

    Constant Value: "video/mp4v-es"

    MIMETYPE_VIDEO_RAW

    Added in API level 21
    public static final String MIMETYPE_VIDEO_RAW

    Constant Value: "video/raw"

    MIMETYPE_VIDEO_SCRAMBLED

    Added in API level 26
    public static final String MIMETYPE_VIDEO_SCRAMBLED

    Constant Value: "video/scrambled"

    MIMETYPE_VIDEO_VP8

    Added in API level 21
    public static final String MIMETYPE_VIDEO_VP8

    Constant Value: "video/x-vnd.on2.vp8"

    MIMETYPE_VIDEO_VP9

    Added in API level 21
    public static final String MIMETYPE_VIDEO_VP9

    Constant Value: "video/x-vnd.on2.vp9"

    PICTURE_TYPE_B

    Added in API level 33
    public static final int PICTURE_TYPE_B

    Picture Type is B Frame.

    Constant Value: 3 (0x00000003)

    PICTURE_TYPE_I

    Added in API level 33
    public static final int PICTURE_TYPE_I

    Picture Type is I Frame.

    Constant Value: 1 (0x00000001)

    PICTURE_TYPE_P

    Added in API level 33
    public static final int PICTURE_TYPE_P

    Picture Type is P Frame.

    Constant Value: 2 (0x00000002)

    PICTURE_TYPE_UNKNOWN

    Added in API level 33
    public static final int PICTURE_TYPE_UNKNOWN

    Picture Type is unknown.

    Constant Value: 0 (0x00000000)

    TYPE_BYTE_BUFFER

    Added in API level 29
    public static final int TYPE_BYTE_BUFFER

    Constant Value: 5 (0x00000005)

    TYPE_FLOAT

    Added in API level 29
    public static final int TYPE_FLOAT

    Constant Value: 3 (0x00000003)

    TYPE_INTEGER

    Added in API level 29
    public static final int TYPE_INTEGER

    Constant Value: 1 (0x00000001)

    TYPE_LONG

    Added in API level 29
    public static final int TYPE_LONG

    Constant Value: 2 (0x00000002)

    TYPE_NULL

    Added in API level 29
    public static final int TYPE_NULL

    Constant Value: 0 (0x00000000)

    TYPE_STRING

    Added in API level 29
    public static final int TYPE_STRING

    Constant Value: 4 (0x00000004)

    VIDEO_ENCODING_STATISTICS_LEVEL_1

    Added in API level 33
    public static final int VIDEO_ENCODING_STATISTICS_LEVEL_1

    Encoding Statistics Level 1. Encoder generates MediaFormat#KEY_PICTURE_TYPE and MediaFormat#KEY_VIDEO_QP_AVERAGE for each frame.

    Constant Value: 1 (0x00000001)

    VIDEO_ENCODING_STATISTICS_LEVEL_NONE

    Added in API level 33
    public static final int VIDEO_ENCODING_STATISTICS_LEVEL_NONE

    Encoding Statistics Level None. Encoder generates no information about Encoding statistics.

    Constant Value: 0 (0x00000000)

    Public constructors

    MediaFormat

    Added in API level 16
    public MediaFormat ()

    Creates an empty MediaFormat

    MediaFormat

    Added in API level 16
    public MediaFormat (MediaFormat other)

    Create a copy of a media format object.

    Parameters
    other MediaFormat: This value cannot be null.

    Public methods

    containsFeature

    Added in API level 29
    public boolean containsFeature (String name)

    Returns true iff a feature of the given name exists in the format.

    Parameters
    name String: This value cannot be null.

    Returns
    boolean

    containsKey

    Added in API level 16
    public boolean containsKey (String name)

    Returns true iff a key of the given name exists in the format.

    Parameters
    name String: This value cannot be null.

    Returns
    boolean

    createAudioFormat

    Added in API level 16
    public static MediaFormat createAudioFormat (String mime, 
                    int sampleRate, 
                    int channelCount)

    Creates a minimal audio format.

    Parameters
    mime String: The mime type of the content. This value cannot be null.

    sampleRate int: The sampling rate of the content.

    channelCount int: The number of audio channels in the content.

    Returns
    MediaFormat This value cannot be null.

    createSubtitleFormat

    Added in API level 19
    public static MediaFormat createSubtitleFormat (String mime, 
                    String language)

    Creates a minimal subtitle format.

    Parameters
    mime String: The mime type of the content. This value cannot be null.

    language String: The language of the content, using either ISO 639-1 or 639-2/T codes. Specify null or "und" if language information is only included in the content. (This will also work if there are multiple language tracks in the content.)

    Returns
    MediaFormat This value cannot be null.

    createVideoFormat

    Added in API level 16
    public static MediaFormat createVideoFormat (String mime, 
                    int width, 
                    int height)

    Creates a minimal video format.

    Parameters
    mime String: The mime type of the content. This value cannot be null.

    width int: The width of the content (in pixels)

    height int: The height of the content (in pixels)

    Returns
    MediaFormat This value cannot be null.

    getByteBuffer

    Added in API level 16
    public ByteBuffer getByteBuffer (String name)

    Returns the value of a ByteBuffer key.

    Parameters
    name String: This value cannot be null.

    Returns
    ByteBuffer null if the key does not exist or the stored value for the key is null

    Throws
    ClassCastException if the stored value for the key is int, long, float or String

    getByteBuffer

    Added in API level 29
    public ByteBuffer getByteBuffer (String name, 
                    ByteBuffer defaultValue)

    Returns the value of a ByteBuffer key, or the default value if the key is missing.

    Parameters
    name String: This value cannot be null.

    defaultValue ByteBuffer: This value cannot be null.

    Returns
    ByteBuffer defaultValue if the key does not exist or the stored value for the key is null

    Throws
    ClassCastException if the stored value for the key is int, long, float or String

    getFeatureEnabled

    Added in API level 21
    public boolean getFeatureEnabled (String feature)

    Returns whether a feature is to be enabled (true) or disabled (false).

    Parameters
    feature String: the name of a MediaCodecInfo.CodecCapabilities feature. This value cannot be null.

    Returns
    boolean

    Throws
    IllegalArgumentException if the feature was neither set to be enabled nor to be disabled.

    getFeatures

    Added in API level 29
    public Set<String> getFeatures ()

    Returns a Set view of the features contained in this MediaFormat. The set is backed by the MediaFormat object, so changes to the format are reflected in the set, and vice-versa. If the format is modified while an iteration over the set is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the format, via the Iterator.remove, Set.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

    Returns
    Set<String> This value cannot be null.

    getFloat

    Added in API level 29
    public float getFloat (String name, 
                    float defaultValue)

    Returns the value of a float key, or the default value if the key is missing.

    Parameters
    name String: This value cannot be null.

    defaultValue float

    Returns
    float defaultValue if the key does not exist or the stored value for the key is null

    Throws
    ClassCastException if the stored value for the key is int, long, ByteBuffer or String

    getFloat

    Added in API level 16
    public float getFloat (String name)

    Returns the value of a float key.

    Parameters
    name String: This value cannot be null.

    Returns
    float

    Throws
    NullPointerException if the key does not exist or the stored value for the key is null
    ClassCastException if the stored value for the key is int, long, ByteBuffer or String

    getInteger

    Added in API level 16
    public int getInteger (String name)

    Returns the value of an integer key.

    Parameters
    name String: This value cannot be null.

    Returns
    int

    Throws
    NullPointerException if the key does not exist or the stored value for the key is null
    ClassCastException if the stored value for the key is long, float, ByteBuffer or String

    getInteger

    Added in API level 29
    public int getInteger (String name, 
                    int defaultValue)

    Returns the value of an integer key, or the default value if the key is missing.

    Parameters
    name String: This value cannot be null.

    defaultValue int

    Returns
    int defaultValue if the key does not exist or the stored value for the key is null

    Throws
    ClassCastException if the stored value for the key is long, float, ByteBuffer or String

    getKeys

    Added in API level 29
    public Set<String> getKeys ()

    Returns a Set view of the keys contained in this MediaFormat. The set is backed by the MediaFormat object, so changes to the format are reflected in the set, and vice-versa. If the format is modified while an iteration over the set is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the format, via the Iterator.remove, Set.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

    Returns
    Set<String> This value cannot be null.

    getLong

    Added in API level 16
    public long getLong (String name)

    Returns the value of a long key.

    Parameters
    name String: This value cannot be null.

    Returns
    long

    Throws
    NullPointerException if the key does not exist or the stored value for the key is null
    ClassCastException if the stored value for the key is int, float, ByteBuffer or String

    getLong

    Added in API level 29
    public long getLong (String name, 
                    long defaultValue)

    Returns the value of a long key, or the default value if the key is missing.

    Parameters
    name String: This value cannot be null.

    defaultValue long

    Returns
    long defaultValue if the key does not exist or the stored value for the key is null

    Throws
    ClassCastException if the stored value for the key is int, float, ByteBuffer or String

    getNumber

    Added in API level 29
    public Number getNumber (String name, 
                    Number defaultValue)

    Returns the value of a numeric key, or the default value if the key is missing.

    Parameters
    name String: This value cannot be null.

    defaultValue Number: This value cannot be null.

    Returns
    Number defaultValue if the key does not exist or the stored value for the key is null

    Throws
    ClassCastException if the stored value for the key is ByteBuffer or String

    getNumber

    Added in API level 29
    public Number getNumber (String name)

    Returns the value of a numeric key. This is provided as a convenience method for keys that may take multiple numeric types, such as KEY_FRAME_RATE, or KEY_I_FRAME_INTERVAL.

    Parameters
    name String: This value cannot be null.

    Returns
    Number null if the key does not exist or the stored value for the key is null

    Throws
    ClassCastException if the stored value for the key is ByteBuffer or String

    getString

    Added in API level 16
    public String getString (String name)

    Returns the value of a string key.

    Parameters
    name String: This value cannot be null.

    Returns
    String null if the key does not exist or the stored value for the key is null

    Throws
    ClassCastException if the stored value for the key is int, long, float or ByteBuffer

    getString

    Added in API level 29
    public String getString (String name, 
                    String defaultValue)

    Returns the value of a string key, or the default value if the key is missing.

    Parameters
    name String: This value cannot be null.

    defaultValue String: This value cannot be null.

    Returns
    String defaultValue if the key does not exist or the stored value for the key is null

    Throws
    ClassCastException if the stored value for the key is int, long, float or ByteBuffer

    getValueTypeForKey

    Added in API level 29
    public int getValueTypeForKey (String name)

    Returns the value type for a key. If the key does not exist, it returns TYPE_NULL.

    Parameters
    name String: This value cannot be null.

    Returns
    int Value is TYPE_NULL, TYPE_INTEGER, TYPE_LONG, TYPE_FLOAT, TYPE_STRING, or TYPE_BYTE_BUFFER

    removeFeature

    Added in API level 29
    public void removeFeature (String name)

    Removes a given feature setting if present. Has no effect if the feature setting is not present.

    Parameters
    name String: This value cannot be null.

    removeKey

    Added in API level 29
    public void removeKey (String name)

    Removes a value of a given key if present. Has no effect if the key is not present.

    Parameters
    name String: This value cannot be null.

    setByteBuffer

    Added in API level 16
    public void setByteBuffer (String name, 
                    ByteBuffer bytes)

    Sets the value of a ByteBuffer key.

    If value is null, it sets a null value that behaves similarly to a missing key. This could be used prior to API level os.Build.VERSION_CODES#Q to effectively remove a key.

    Parameters
    name String: This value cannot be null.

    bytes ByteBuffer: This value may be null.

    setFeatureEnabled

    Added in API level 21
    public void setFeatureEnabled (String feature, 
                    boolean enabled)

    Sets whether a feature is to be enabled (true) or disabled (false). If enabled is true, the feature is requested to be present. Otherwise, the feature is requested to be not present.

    Parameters
    feature String: the name of a MediaCodecInfo.CodecCapabilities feature. This value cannot be null.

    enabled boolean

    setFloat

    Added in API level 16
    public void setFloat (String name, 
                    float value)

    Sets the value of a float key.

    Parameters
    name String: This value cannot be null.

    value float

    setInteger

    Added in API level 16
    public void setInteger (String name, 
                    int value)

    Sets the value of an integer key.

    Parameters
    name String: This value cannot be null.

    value int

    setLong

    Added in API level 16
    public void setLong (String name, 
                    long value)

    Sets the value of a long key.

    Parameters
    name String: This value cannot be null.

    value long

    setString

    Added in API level 16
    public void setString (String name, 
                    String value)

    Sets the value of a string key.

    If value is null, it sets a null value that behaves similarly to a missing key. This could be used prior to API level os.Build.VERSION_CODES#Q to effectively remove a key.

    Parameters
    name String: This value cannot be null.

    value String: This value may be null.

    toString

    Added in API level 16
    public String toString ()

    Returns a string representation of the object.

    Returns
    String This value cannot be null.