Camera2 擴充功能 API

注意：本頁面所述是指 Camera2 套件。除非應用程式需要 Camera2 的特定低階功能，否則建議使用 CameraX。CameraX 和 Camera2 均支援 Android 5.0 (API 級別 21) 以上版本。

Camera2 提供擴充功能 API，可用於存取裝置製造商在不同 Android 裝置上實作的擴充功能。如需支援的擴充功能模式清單，請參閱「相機擴充功能」。

如需支援擴充功能的裝置清單，請參閱「支援的裝置」。

擴充功能架構

下圖顯示相機擴充功能的架構。

Camera2 應用程式可透過 Camera2 API 使用擴充功能。相機 2 API 可讓您查詢可用的擴充功能、設定擴充功能 ，並與 Camera Extensions OEM 程式庫通訊。這個 可讓應用程式使用「夜晚」、「高動態範圍」、「自動」、「散景」或 修容功能

測試相機裝置是否符合 Camera2 Extensions API 相容性

下列程式碼片段會檢查裝置是否支援 Camera2 擴充功能 API。並非所有裝置或裝置都支援部分擴充功能 。程式碼片段會傳回支援相容相機 ID 的清單 相機擴充功能

private fun getExtensionCameraIds(cameraManager: CameraManager): List<String> =
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
        cameraManager.cameraIdList.filter { cameraId ->
            val characteristics = cameraManager.getCameraCharacteristics(cameraId)
            val extensionCharacteristics =
                cameraManager.getCameraExtensionCharacteristics(cameraId)
            val capabilities =
                characteristics.get(CameraCharacteristics.REQUEST_AVAILABLE_CAPABILITIES)
            extensionCharacteristics.supportedExtensions.isNotEmpty() &&
                    capabilities?.contains(
                        CameraCharacteristics.REQUEST_AVAILABLE_CAPABILITIES_BACKWARD_COMPATIBLE
                    ) ?: false
        }
    } else emptyList()

private List<String> getExtensionCameraIds(CameraManager cameraManager)
        throws CameraAccessException {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
        return Arrays.stream(cameraManager.getCameraIdList()).filter(cameraId -> {
            try {
                CameraCharacteristics characteristics =
                        cameraManager.getCameraCharacteristics(cameraId);
                CameraExtensionCharacteristics extensionCharacteristics =
                        cameraManager.getCameraExtensionCharacteristics(cameraId);
                IntStream capabilities =
                    Arrays.stream(
                                characteristics.get(
                                        CameraCharacteristics.REQUEST_AVAILABLE_CAPABILITIES
                                )
                        );
                return !extensionCharacteristics.getSupportedExtensions().isEmpty() &&
                       capabilities.anyMatch(capability -> capability == CameraCharacteristics
                                        .REQUEST_AVAILABLE_CAPABILITIES_BACKWARD_COMPATIBLE
                        );
            } catch (CameraAccessException e) {
                throw new RuntimeException(e);
            }
        }).collect(Collectors.toList());
    } else {
        return Collections.emptyList();
    }
}

使用 Camera2 Extensions API 建立 CameraExtensionSession

與相容裝置搭配使用 Camera2 Extensions API 時，你可以 特定相機擴充功能以下程式碼片段為 如何建立 CameraExtensionSession ，在現有 Camera2 應用程式中使用夜間拍攝模式。

private val captureCallbacks = object : CameraExtensionSession.ExtensionCaptureCallback() {
    // Implement Capture Callbacks
}
private val extensionSessionStateCallback = object : CameraExtensionSession.StateCallback() {
    override fun onConfigured(session: CameraExtensionSession) {
        cameraExtensionSession = session
        try {
            val captureRequest =
                cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW).apply {
                    addTarget(previewSurface)
                }.build()
            session.setRepeatingRequest(
                captureRequest,
                Dispatchers.IO.asExecutor(),
                captureCallbacks
            )
        } catch (e: CameraAccessException) {
            Snackbar.make(
                previewView,
                "Failed to preview capture request",
                Snackbar.LENGTH_SHORT
            ).show()
            requireActivity().finish()
        }
    }

    override fun onClosed(session: CameraExtensionSession) {
        super.onClosed(session)
        cameraDevice.close()
    }

    override fun onConfigureFailed(session: CameraExtensionSession) {
        Snackbar.make(
            previewView,
            "Failed to start camera extension preview",
            Snackbar.LENGTH_SHORT
        ).show()
        requireActivity().finish()
    }
}

private fun startExtensionSession() {
    val outputConfig = arrayListOf(
        OutputConfiguration(stillImageReader.surface),
        OutputConfiguration(previewSurface)
    )
    val extensionConfiguration = ExtensionSessionConfiguration(
        CameraExtensionCharacteristics.EXTENSION_NIGHT,
        outputConfig,
        Dispatchers.IO.asExecutor(),
        extensionSessionStateCallback
    )
    cameraDevice.createExtensionSession(extensionConfiguration)
}

private CameraExtensionSession.ExtensionCaptureCallback captureCallbacks =
        new CameraExtensionSession.ExtensionCaptureCallback() {
            // Implement Capture Callbacks
        };

private CameraExtensionSession.StateCallback extensionSessionStateCallback =
        new CameraExtensionSession.StateCallback() {
            @Override
            public void onConfigured(@NonNull CameraExtensionSession session) {
                cameraExtensionSession = session;
                try {
                    CaptureRequest.Builder captureRequestBuilder =
                            cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
                    captureRequestBuilder.addTarget(previewSurface);
                    CaptureRequest captureRequest = captureRequestBuilder.build();
                    session.setRepeatingRequest(captureRequest, backgroundExecutor, captureCallbacks);
                } catch (CameraAccessException e) {
                    Snackbar.make(
                            previewView,
                            "Failed to preview capture request",
                            Snackbar.LENGTH_SHORT
                    ).show();
                    requireActivity().finish();
                }
            }

            @Override
            public void onClosed(@NonNull CameraExtensionSession session) {
                super.onClosed(session);
                cameraDevice.close();
            }

            @Override
            public void onConfigureFailed(@NonNull CameraExtensionSession session) {
                Snackbar.make(
                        previewView,
                        "Failed to start camera extension preview",
                        Snackbar.LENGTH_SHORT
                ).show();
                requireActivity().finish();
            }
        };

private void startExtensionSession() {
    ArrayList<OutputConfiguration> outputConfig = new ArrayList<>();
    outputConfig.add(new OutputConfiguration(stillImageReader.getSurface()));
    outputConfig.add(new OutputConfiguration(previewSurface));
    ExtensionSessionConfiguration extensionConfiguration = new ExtensionSessionConfiguration(
            CameraExtensionCharacteristics.EXTENSION_NIGHT,
            outputConfig,
            backgroundExecutor,
            extensionSessionStateCallback
    );
}

其他資源

若需更多資訊，請參閲 CameraExtensionCharacteristics敬上 並查看公開的 Camera2 Extensions API 範例 瞭解詳情。