I want to compress locally saved video file to a smaller size in order to upload to a server.
Since i used MediaCodec , i have found some tips to compress video . Here are the steps that i followed
1) . Extracted the media file using MediaExrtactor and Decoded it.
2) . Creates the Encoder with required file format
3) . Create muxer to save file in local storage. (not complete)
Question : But i dont know how to encode the already decoded stream and save the stream in to the local storage using MediaMuxer.
public class CompressMedia {
private static final String SAMPLE = Environment
.getExternalStorageDirectory() + "/DCIM/Camera/20140506_174959.mp4";
private static final String OUTPUT_PATH = Environment
.getExternalStorageDirectory()
+ "/DCIM/Camera/20140506_174959_REC.mp4";
private MediaExtractor extractor;
private MediaCodec decoder;
private MediaCodec encoder;
String mime;
private static final String MIME_TYPE = "video/avc";
public void extractMediaFile() {
// work plan
// locate media file
// extract media file using Media Extractor
// retrieve decoded frames
extractor = new MediaExtractor();
try {
extractor.setDataSource(SAMPLE);
} catch (IOException e) {
// TODO Auto-generated catch block
// file not found
e.printStackTrace();
}
// add decoded frames
for (int i = 0; i < extractor.getTrackCount(); i++) {
MediaFormat format = extractor.getTrackFormat(i);
mime = format.getString(MediaFormat.KEY_MIME);
if (mime.startsWith("video/")) {
extractor.selectTrack(i);
decoder = MediaCodec.createDecoderByType(mime);
decoder.configure(format, null, null, 0);
break;
}
}
if (decoder == null) {
Log.e("DecodeActivity", "Can't find video info!");
return;
}
// - start decoder -
decoder.start();
extractor.selectTrack(0);
// - decoded frames can obtain in here -
}
private void createsEncoder() {
// creates media encoder to set formats
encoder = MediaCodec.createDecoderByType(MIME_TYPE);
// init media format
MediaFormat mediaFormat = MediaFormat.createVideoFormat(MIME_TYPE, /* 640 */
320, /* 480 */240);
mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, 400000);
mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, 25);
mediaFormat.setInteger(MediaFormat.KEY_COLOR_FORMAT,
MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420SemiPlanar);
mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 5);
encoder.configure(mediaFormat, null, null,
MediaCodec.CONFIGURE_FLAG_ENCODE);
encoder.start();
// - encoded data format is avaiable in here
}
private void createMuxer() {
// creates media muxer - media muxer will be used to write the final
// strem in to a desired file :)
try {
MediaMuxer muxer = new MediaMuxer(OUTPUT_PATH,
OutputFormat.MUXER_OUTPUT_MPEG_4);
int videoTrackIndex = muxer.addTrack(encoder.getOutputFormat());
//muxer.writeSampleData(videoTrackIndex, inputBuffers, bufferInfo);
muxer.start();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
Here are the links that i follwed
Android MediaCodec: Reduce mp4 video size and
Video compression on android using new MediaCodec Library
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