Android MediaCodec: encoding falis because no sync frames for video track

Question

I am planning to convert a video file to another video file with different bitrate, fps, etc.

Bascially I follow the examples in http://bigflake.com/mediacodec

However, Log shows error of no sync frames for video track:

submitted frame 5 to dec, size=47398
no output from encoder available
decoder output format changed: {height=1080, what=1869968451, color-format=2141391875, slice-height=1088, crop-left=0, width=1920, crop-bottom=1079, crop-top=0, mime=video/raw, stride=1920, crop-right=1919}
no output from encoder available
surface decoder given buffer 0 (size=3137536)
awaiting frame
E/MPEG4Writer(3464): There are no sync frames for video track
W/MPEG4Writer(3464): 0-duration samples found: 1
Stopping Video track

Then the program exits.

I searched online. fadden says "Make sure you are passing all of the MediaCodec.BufferInfo values through to the MediaMuxer -- that's where the flags are. The sync frames will have the BUFFER_FLAG_SYNC_FRAME flag set."

However, from the example from http://bigflake.com/mediacodec, it uses:

outputFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL,10); 

This seems to mean encoder will determine which frame to be assigned with the key frame.

Seems no much related information online regarding this issue. Oh, wish bigflake.com has more examples related to some problems that developers are interested in (such as change the format parameters of one existing video file)

==[Update]== Here are some code I use:

MediaFormat outputFormat = MediaFormat.createVideoFormat(MIME_TYPE, mWidth, mHeight);
outputFormat.setInteger(MediaFormat.KEY_COLOR_FORMAT,
        MediaCodecInfo.CodecCapabilities.COLOR_FormatSurface);
outputFormat.setInteger(MediaFormat.KEY_BIT_RATE,5000000);
outputFormat.setInteger(MediaFormat.KEY_FRAME_RATE,30);
outputFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL,5); 
encoder = MediaCodec.createEncoderByType(MIME_TYPE);
encoder.configure(outputFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
inputSurface = new InputSurface(encoder.createInputSurface());
inputSurface.makeCurrent();
encoder.start();
...
try {
    mMuxer = new MediaMuxer(ouVideoFileName, MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
} catch (IOException ioe) {
    throw new RuntimeException("MediaMuxer creation failed", ioe);
}
...
// now that we have the Magic Goodies, start the muxer
mTrackIndex = mMuxer.addTrack(newFormat);
mMuxer.start();
mMuxerStarted = true;
...
mMuxer.writeSampleData(mTrackIndex, encodedData, info_encoder);

Then where do I miss to pass parameters to mMuxer? It seems I have passed all required parameters.

==[Update 2]== In:

int encoderStatus = encoder.dequeueOutputBuffer(info_encoder, TIMEOUT_USEC);

I log out info_encoder.flags: from frames 0 to 5, the flags = 0. They are not flags for Key Frame. The input video file is a short one recorded by the device, .mp4, and plays correctly. After frame 5, MPEG4Write complains "There are no sync frames for video track".

==[Update 3]== BTW, I find that the encoding part between DecodeEditEncodeTest.java and EncodeDecodeTest.java are different. The encoding part in EncodeDecodeTest.java includes encoder.dequeueInputBuffer, while in DecodeEditEncodeTest.java no lines related to encoder.dequeueInputBuffer at all. Do you think this would be a problem? But in the first place, why are they different in the two examples?

==[Update 4]== I copy the code to the class ExtractMpegFramesTest Then in my main activity, I have a button. After I click the button, it will call:

// test:
ExtractMpegFramesTest mTest = new ExtractMpegFramesTest();
try {
    mTest.testExtractMpegFrames();
} catch (Throwable e1) {
    // TODO Auto-generated catch block
    e1.printStackTrace();
}

Error:

E/ACodec(11342): [OMX.qcom.video.decoder.avc] storeMetaDataInBuffers failed w/ err -2147483648
java.lang.RuntimeException: frame wait timed out
ExtractMpegFramesTest$CodecOutputSurface.awaitNewImage(ExtractMpegFramesTest.java:496)