/**
* Edits a video file, saving the contents to a new file. This involves decoding and re-encoding,
* not to mention conversions between YUV and RGB, and so may be lossy.
*
* <p>If we recognize the decoded format we can do this in Java code using the ByteBuffer[]
* output, but it's not practical to support all OEM formats. By using a SurfaceTexture for output
* and a Surface for input, we can avoid issues with obscure formats and can use a fragment shader
* to do transformations.
*/
private VideoChunks editVideoFile(VideoChunks inputData) {
if (VERBOSE) Log.d(TAG, "editVideoFile " + mWidth + "x" + mHeight);
VideoChunks outputData = new VideoChunks();
MediaCodec decoder = null;
MediaCodec encoder = null;
InputSurface inputSurface = null;
OutputSurface outputSurface = null;
try {
MediaFormat inputFormat = inputData.getMediaFormat();
// Create an encoder format that matches the input format. (Might be able to just
// re-use the format used to generate the video, since we want it to be the same.)
MediaFormat outputFormat = MediaFormat.createVideoFormat(MIME_TYPE, mWidth, mHeight);
outputFormat.setInteger(
MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);
outputFormat.setInteger(
MediaFormat.KEY_BIT_RATE, inputFormat.getInteger(MediaFormat.KEY_BIT_RATE));
outputFormat.setInteger(
MediaFormat.KEY_FRAME_RATE, inputFormat.getInteger(MediaFormat.KEY_FRAME_RATE));
outputFormat.setInteger(
MediaFormat.KEY_I_FRAME_INTERVAL,
inputFormat.getInteger(MediaFormat.KEY_I_FRAME_INTERVAL));
outputData.setMediaFormat(outputFormat);
encoder = MediaCodec.createEncoderByType(MIME_TYPE);
encoder.configure(outputFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
inputSurface = new InputSurface(encoder.createInputSurface());
inputSurface.makeCurrent();
encoder.start();
// OutputSurface uses the EGL context created by InputSurface.
decoder = MediaCodec.createDecoderByType(MIME_TYPE);
outputSurface = new OutputSurface();
outputSurface.changeFragmentShader(FRAGMENT_SHADER);
decoder.configure(inputFormat, outputSurface.getSurface(), null, 0);
decoder.start();
editVideoData(inputData, decoder, outputSurface, inputSurface, encoder, outputData);
} finally {
if (VERBOSE) Log.d(TAG, "shutting down encoder, decoder");
if (outputSurface != null) {
outputSurface.release();
}
if (inputSurface != null) {
inputSurface.release();
}
if (encoder != null) {
encoder.stop();
encoder.release();
}
if (decoder != null) {
decoder.stop();
decoder.release();
}
}
return outputData;
}
/**
* Generates a test video file, saving it as VideoChunks. We generate frames with GL to avoid
* having to deal with multiple YUV formats.
*
* @return true on success, false on "soft" failure
*/
private boolean generateVideoFile(VideoChunks output) {
if (VERBOSE) Log.d(TAG, "generateVideoFile " + mWidth + "x" + mHeight);
MediaCodec encoder = null;
InputSurface inputSurface = null;
try {
MediaCodecInfo codecInfo = selectCodec(MIME_TYPE);
if (codecInfo == null) {
// Don't fail CTS if they don't have an AVC codec (not here, anyway).
Log.e(TAG, "Unable to find an appropriate codec for " + MIME_TYPE);
return false;
}
if (VERBOSE) Log.d(TAG, "found codec: " + codecInfo.getName());
// We avoid the device-specific limitations on width and height by using values that
// are multiples of 16, which all tested devices seem to be able to handle.
MediaFormat format = MediaFormat.createVideoFormat(MIME_TYPE, mWidth, mHeight);
// Set some properties. Failing to specify some of these can cause the MediaCodec
// configure() call to throw an unhelpful exception.
format.setInteger(
MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);
format.setInteger(MediaFormat.KEY_BIT_RATE, mBitRate);
format.setInteger(MediaFormat.KEY_FRAME_RATE, FRAME_RATE);
format.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, IFRAME_INTERVAL);
if (VERBOSE) Log.d(TAG, "format: " + format);
output.setMediaFormat(format);
// Create a MediaCodec for the desired codec, then configure it as an encoder with
// our desired properties.
encoder = MediaCodec.createByCodecName(codecInfo.getName());
encoder.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
inputSurface = new InputSurface(encoder.createInputSurface());
inputSurface.makeCurrent();
encoder.start();
generateVideoData(encoder, inputSurface, output);
} finally {
if (encoder != null) {
if (VERBOSE) Log.d(TAG, "releasing encoder");
encoder.stop();
encoder.release();
if (VERBOSE) Log.d(TAG, "released encoder");
}
if (inputSurface != null) {
inputSurface.release();
}
}
return true;
}
/**
* Create the display surface out of the encoder. The data to encoder will be fed from this
* Surface itself.
*
* @return
* @throws IOException
*/
@TargetApi(19)
private Surface createDisplaySurface() throws IOException {
MediaFormat mMediaFormat =
MediaFormat.createVideoFormat(CodecUtils.MIME_TYPE, CodecUtils.WIDTH, CodecUtils.HEIGHT);
mMediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, (int) (1024 * 1024 * 0.5));
mMediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, 30);
mMediaFormat.setInteger(
MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);
mMediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 1);
Log.i(TAG, "Starting encoder");
encoder = MediaCodec.createEncoderByType(CodecUtils.MIME_TYPE);
encoder.configure(mMediaFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
Surface surface = encoder.createInputSurface();
return surface;
}
public void prepareEncode() {
MediaFormat mediaFormat = MediaFormat.createVideoFormat(MIME_TYPE, mWidth, mHeight);
// 描述视频格式的信息
mediaFormat.setInteger(
MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);
mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, BITRATE); // 比特率
mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, FRAME_RATE); // 帧数
mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, IFRAME_INTERVAL); // 关键帧间隔时间
try {
mEncoder = MediaCodec.createEncoderByType(MIME_TYPE);
mEncoder.configure(mediaFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
mSurface = mEncoder.createInputSurface();
mEncoder.start();
mediaMuxer = new MediaMuxer(filePath, MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* Configures encoder and muxer state, and prepares the input Surface. Initializes mEncoder,
* mMuxer, mRecordingSurface, mBufferInfo, mTrackIndex, and mMuxerStarted.
*/
private void configureMediaCodecEncoder() {
mBufferInfo = new MediaCodec.BufferInfo();
MediaFormat format =
MediaFormat.createVideoFormat(MIME_TYPE, mStreamSize.getWidth(), mStreamSize.getHeight());
/**
* Set encoding properties. Failing to specify some of these can cause the MediaCodec
* configure() call to throw an exception.
*/
format.setInteger(
MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);
format.setInteger(MediaFormat.KEY_BIT_RATE, mEncBitRate);
format.setInteger(MediaFormat.KEY_FRAME_RATE, FRAME_RATE);
format.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, IFRAME_INTERVAL);
Log.i(TAG, "configure video encoding format: " + format);
// Create/configure a MediaCodec encoder.
mEncoder = MediaCodec.createEncoderByType(MIME_TYPE);
mEncoder.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
mRecordingSurface = mEncoder.createInputSurface();
mEncoder.start();
String outputFileName = getOutputMediaFileName();
if (outputFileName == null) {
throw new IllegalStateException("Failed to get video output file");
}
/**
* Create a MediaMuxer. We can't add the video track and start() the muxer until the encoder
* starts and notifies the new media format.
*/
try {
mMuxer = new MediaMuxer(outputFileName, MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
} catch (IOException ioe) {
throw new IllegalStateException("MediaMuxer creation failed", ioe);
}
mMuxerStarted = false;
}