问题
I have two mpeg-ts + h.264 video files, which I attempt to read on an Android device (Samsung Tab A 10.1") with ExoPlayer:
SimpleExoPlayerView view = new SimpleExoPlayerView(this);
TrackSelection.Factory videoTrackSelectionFactory = new AdaptiveVideoTrackSelection.Factory(new DefaultBandwidthMeter());
TrackSelector trackSelector = new DefaultTrackSelector(videoTrackSelectionFactory);
SimpleExoPlayer mediaPlayer = ExoPlayerFactory.newSimpleInstance(this, trackSelector, new DefaultLoadControl());
DataSource.Factory dataSourceFactory = new DefaultDataSourceFactory(this, Util.getUserAgent(this, getString(R.string.app_name)));
ExtractorsFactory extractorsFactory = new DefaultExtractorsFactory();
MediaSource source = new ExtractorMediaSource(uri, dataSourceFactory, extractorsFactory, null, null);
view.setPlayer(mediaPlayer);
mediaPlayer.setPlayWhenReady(true);
mediaPlayer.prepare(source);
The first one succeeds (image is correctly displayed) but the second one fails (no image displayed), though they are both very similar in terms of video characteristics. I'd like to understand why.
I used mediainfo to extract video encoding details.
First video (successful):
General
ID : 0 (0x0)
Complete name : 1080i.ts
Format : MPEG-TS
File size : 56.7 MiB
Duration : 47s 456ms
Overall bit rate mode : Constant
Overall bit rate : 10.0 Mbps
Video
ID : 256 (0x100)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : Yes
Format settings, ReFrames : 2 frames
Codec ID : 27
Duration : 47s 282ms
Bit rate : 9 185 Kbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : MBAFF
Bits/(Pixel*Frame) : 0.148
Stream size : 51.8 MiB (91%)
Second video (failed):
General
ID : 1 (0x1)
Complete name : fr5.ts
Format : MPEG-TS
File size : 13.8 MiB
Duration : 32s 270ms
Overall bit rate mode : Variable
Overall bit rate : 3 557 Kbps
Video
ID : 420 (0x1A4)
Menu ID : 1045 (0x415)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : Yes
Format settings, ReFrames : 4 frames
Codec ID : 27
Duration : 31s 760ms
Bit rate : 3 252 Kbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 25.000 fps
Standard : Component
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : MBAFF
Bits/(Pixel*Frame) : 0.063
Stream size : 12.3 MiB (89%)
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709
回答1:
The differences between the two files that stand out are the bit rates. The working one has a much higher bit rate, and it is constant, whereas the broken one has the same high resolution, but a much lower and variable bit rate. Without knowing more than the provided stats, I would blame the tool used to encode the video. Maybe something about the configuration causes the encoder to output black frames. Have you tried the same files on a different device? Can you re-encode with slightly different settings?
来源：https://stackoverflow.com/questions/43073827/mpeg-ts-h-264-with-exoplayer