WMV video does not seek correctly in Windows Media Player on Windows 7

[vpi]

When reading raw packets from a source WMV video file using the av_read_frame() function of the libavcodec library and writing them as-is to an output file using the av_write_frame() function, the output file plays but does not seek correctly in Windows Media Player 12 on Windows 7. There is a noticable delay before playback resumes (presumably Windows Media Player is waiting for the next key frame to arrive, which can take awhile).

The output file plays and seeks fine in Windows Media Player 11 on Windows XP, and the source file plays and seeks fine in both Windows versions. So the issue is in playing libavcodec's output file in Windows Media Player 12.

What we want to do is make an exact copy of a video file with specific frames blacked out based on given timestamps and durations (is libavfilter capable of handling this better? How to hook it up in code?). For performance, we only decode/encode the video frames that need to be blacked out, the rest of the packets are read/written as-is. For testing purposes though, the following stripped down code is what our current logic looks like just to make an unaltered copy of the video (error handling removed for brevity):

AVFormatContext *inputFormatCtx;
AVCodecContext *inputCodecCtx;
int videoStreamIndex;

AVCodecContext *outputCodecCtx;
AVFormatContext *outputFormatCtx;

avformat_open_input(&inputFormatCtx, inputFileName, NULL, NULL);
avformat_find_stream_info(inputFormatCtx, NULL);

for(unsigned int i=0; i < inputFormatCtx->nb_streams; i++)
{
	if ( inputFormatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO)
	{
		inputCodecCtx = inputFormatCtx->streams[i]->codec;
		videoStreamIndex = i;
		break;
	}
}

AVCodec *pDecoder = avcodec_find_decoder( inputFormatCtx->codec_id );
avcodec_open2( inputFormatCtx, pDecoder, NULL );

AVCodec *pEncoder = avcodec_find_encoder( inputCodecCtx->codec_id );

avformat_alloc_output_context2(&outputFormatCtx, NULL, "asf", outputFileName);

outputFormatCtx->oformat->audio_codec = CODEC_ID_NONE;
outputFormatCtx->oformat->video_codec = inputCodecCtx->codec_id;
outputFormatCtx->audio_codec_id = CODEC_ID_NONE;
outputFormatCtx->video_codec_id = inputCodecCtx->codec_id;
outputFormatCtx->duration = inputFormatCtx->duration;
	
av_dict_copy( &(outputFormatCtx->metadata), inputFormatCtx->metadata, 0);
av_dict_set( &(outputFormatCtx->metadata), "Author", "VPI", 0 );

AVStream *stream = avformat_new_stream(outputFormatCtx, pEncoder);
outputCodecCtx = stream->codec;
//avcodec_copy_context( outputCodecCtx, inputCodecCtx );
outputCodecCtx->pix_fmt = inputCodecCtx->pix_fmt;
outputCodecCtx->time_base.num = 1;
outputCodecCtx->time_base.den = 1;
outputCodecCtx->width = inputCodecCtx->width;
outputCodecCtx->height = inputCodecCtx->height;
outputCodecCtx->bit_rate = inputCodecCtx->bit_rate;
outputCodecCtx->bit_rate_tolerance = inputCodecCtx->bit_rate_tolerance;
outputCodecCtx->qmax = inputCodecCtx->qmax;
outputCodecCtx->qmin = inputCodecCtx->qmin;		

if ( outputformatCtx->oformat->flags & AVFMT_GLOBALHEADER )
	outputCodecCtx->flags |= CODEC_FLAG_GLOBAL_HEADER;

avcodec_open2(outputCodecCtx, pEncoder, NULL);
avio_open( &(outputFormatCtx->pb), outputFormatCtx->filename, URL_WRONLY);
avformat_write_header( outputFormatCtx, NULL );

AVPacket packet;
av_init_packet( &packet );
do
{
	if (NULL != packet.data)
	{
		av_free_packet(&packet);
		packet.data = NULL;
	}

	if ( av_read_frame( inputFormatCtx, &packet ) < 0 )
		break;

	if ( packet.stream_index == videoStreamIndex )
		av_write_frame( outputFormatCtx, &packet );
}
while (true);

av_write_trailer( outputFormatCtx );

avcodec_close(outputCodecCtx);
avio_close(outputFormatCtx->pb)
outputFormatCtx->pb = NULL;
avformat_free_context( outputFormatCtx );

avcodec_close(inputCodecCtx);
avio_close(inputFormatCtx->pb);
inputFormatCtx->pb = NULL;
avformat_close_input(&inputFormatCtx);

if ( NULL != packet.data )
{
	av_free_packet(&packet);
	packet.data = NULL;
}

The same issue can be reproduced with the command-line ffmpeg.exe application using the following command-line:

ffmpeg -i seeks_fine.wmv -vcodec copy seeks_delayed.wmv

Here is the console output:

ffmpeg version N-36635-gceb0dd9 Copyright (c) 2000-2012 the FFmpeg developers
  built on Jan  9 2012 17:42:37 with gcc 4.6.2
  configuration: --disable-static --enable-shared --enable-gpl --enable-version3 --disable-w32threads --enable-runtime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid --enable-zlib
  libavutil      51. 34.100 / 51. 34.100
  libavcodec     53. 54.100 / 53. 54.100
  libavformat    53. 29.100 / 53. 29.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 58.100 /  2. 58.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  6.100 /  0.  6.100
  libpostproc    51.  2.100 / 51.  2.100
Input #0, asf, from 'C:\Documents and Settings\rp\Desktop\PCI Scrubbing\seeks_fine.wmv':
  Metadata:
    WMFSDKVersion   : 9.00.00.3250
    WMFSDKNeeded    : 0.0.0.0000
    IsVBR           : 1
    VBR Peak        : 1045
    Buffer Average  : 2090
  Duration: 00:00:56.00, start: 0.000000, bitrate: 31 kb/s
    Stream #0:0(eng): Video: wmv1 (WMV1 / 0x31564D57), yuv420p, 1024x768, 29 kb/s, 1 tbr, 1k tbn, 1k tbc
Output #0, asf, to 'C:\Documents and Settings\rp\Desktop\PCI Scrubbing\seeks_delayed.wmv':
  Metadata:
    WMFSDKVersion   : 9.00.00.3250
    WMFSDKNeeded    : 0.0.0.0000
    IsVBR           : 1
    VBR Peak        : 1045
    Buffer Average  : 2090
    WM/EncodingSettings: Lavf53.29.100
    Stream #0:0(eng): Video: wmv1 (WMV1 / 0x31564D57), yuv420p, 1024x768, q=2-31, 29 kb/s, 1k tbn, 1k tbc
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
frame=   57 fps=  0 q=-1.0 Lsize=     214kB time=00:00:56.00 bitrate=  31.2kbits/s
video:208kB audio:0kB global headers:0kB muxing overhead 2.746522%

Attached are the two video files.

[vpi]

Input file that seeks correctly

[vpi]

Here is the console output with verbose logging:

ffmpeg -v 9 -loglevel 99 -i seeks_fine.wmv -vcodec copy seeks_delayed.wmv

ffmpeg version N-36635-gceb0dd9 Copyright (c) 2000-2012 the FFmpeg developers
  built on Jan  9 2012 17:42:37 with gcc 4.6.2
  configuration: --disable-static --enable-shared --enable-gpl --enable-version3 --disable-w32threads --enable-runtime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid --enable-zlib
  libavutil      51. 34.100 / 51. 34.100
  libavcodec     53. 54.100 / 53. 54.100
  libavformat    53. 29.100 / 53. 29.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 58.100 /  2. 58.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  6.100 /  0.  6.100
  libpostproc    51.  2.100 / 51.  2.100
[asf @ 003EA060] Format asf probed with size=2048 and score=100
[asf @ 003EA060] Unsupported value type 1 in tag ASFLeakyBucketPairs.
[asf @ 003EA060] gpos mismatch our pos=24, end=104
[asf @ 003EA060] gpos mismatch our pos=24, end=26
[asf @ 003EA060] gpos mismatch our pos=24, end=1536
[asf @ 003EA060] gpos mismatch our pos=24, end=34
[asf @ 003EA060] gpos mismatch our pos=24, end=32
[wmv1 @ 00B25B40] err{or,}_recognition separate: 1; 1
[wmv1 @ 00B25B40] err{or,}_recognition combined: 1; 10001
[wmv1 @ 00B25B40] Unsupported bit depth: 0
[asf @ 003EA060] All info found
Input #0, asf, from 'C:\Documents and Settings\rp\Desktop\PCI Scrubbing\seeks_fine.wmv':
  Metadata:
    WMFSDKVersion   : 9.00.00.3250
    WMFSDKNeeded    : 0.0.0.0000
    IsVBR           : 1
    VBR Peak        : 1045
    Buffer Average  : 2090
  Duration: 00:00:56.00, start: 0.000000, bitrate: 31 kb/s
    Stream #0:0(eng), 41, 1/1000: Video: wmv1 (WMV1 / 0x31564D57), yuv420p, 1024x768, 1/1000, 29 kb/s, 1 tbr, 1k tbn, 1k tbc
Output #0, asf, to 'C:\Documents and Settings\rp\Desktop\PCI Scrubbing\seeks_delayed.wmv':
  Metadata:
    WMFSDKVersion   : 9.00.00.3250
    WMFSDKNeeded    : 0.0.0.0000
    IsVBR           : 1
    VBR Peak        : 1045
    Buffer Average  : 2090
    WM/EncodingSettings: Lavf53.29.100
    Stream #0:0(eng), 0, 1/1000: Video: wmv1 (WMV1 / 0x31564D57), yuv420p, 1024x768, 1/1000, q=2-31, 29 kb/s, 1k tbn, 1k tbc
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
frame=   57 fps=  0 q=-1.0 Lsize=     214kB time=00:00:56.00 bitrate=  31.2kbits/s
video:208kB audio:0kB global headers:0kB muxing overhead 2.746522%

[reimar]

Please always test with a recent version. This was most likely fixed in bd603494f905a7db92fc04eab9c0f6793b0ed7d1 on April 4th.
Until then I'll assume this is invalid due to being cause by using an outdated version.

[vpi]

Retested with the latest ffmpeg.exe executable that is dated April 9th (though the console output says April 3rd). The same seeking issue still exists

Here is the console output:

ffmpeg -v 9 -loglevel 99 -i seeks_fine.wmv -vcodec copy seeks_delayed.wmv

ffmpeg version N-39494-g41a097a Copyright (c) 2000-2012 the FFmpeg developers
  built on Apr  3 2012 20:20:04 with gcc 4.6.2
  configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-runtime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid --enable-zlib
  libavutil      51. 44.100 / 51. 44.100
  libavcodec     54. 12.100 / 54. 12.100
  libavformat    54.  3.100 / 54.  3.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 66.101 /  2. 66.101
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 10.100 /  0. 10.100
  libpostproc    52.  0.100 / 52.  0.100
[asf @ 0219AC20] Format asf probed with size=2048 and score=100
[asf @ 0219AC20] Unsupported value type 1 in tag ASFLeakyBucketPairs.
[asf @ 0219AC20] gpos mismatch our pos=24, end=104
[asf @ 0219AC20] gpos mismatch our pos=24, end=26
[asf @ 0219AC20] gpos mismatch our pos=24, end=1536
[asf @ 0219AC20] gpos mismatch our pos=24, end=34
[asf @ 0219AC20] gpos mismatch our pos=24, end=32
[asf @ 0219AC20] All info found
Input #0, asf, from 'C:\Documents and Settings\rp\Desktop\PCI Scrubbing\seeks_fine.wmv':
  Metadata:
    WMFSDKVersion   : 9.00.00.3250
    WMFSDKNeeded    : 0.0.0.0000
    IsVBR           : 1
    VBR Peak        : 1045
    Buffer Average  : 2090
  Duration: 00:00:56.00, start: 0.000000, bitrate: 31 kb/s
    Stream #0:0(eng), 41, 1/1000: Video: wmv1 (WMV1 / 0x31564D57), yuv420p, 1024x768, 1/1000, 29 kb/s, 1 tbr, 1k tbn, 1k tbc
Output #0, asf, to 'C:\Documents and Settings\rp\Desktop\PCI Scrubbing\seeks_delayed.wmv':
  Metadata:
    WMFSDKVersion   : 9.00.00.3250
    WMFSDKNeeded    : 0.0.0.0000
    IsVBR           : 1
    VBR Peak        : 1045
    Buffer Average  : 2090
    WM/EncodingSettings: Lavf54.3.100
    Stream #0:0(eng), 0, 1/1000: Video: wmv1 (WMV1 / 0x31564D57), yuv420p, 1024x768, 1/1000, q=2-31, 29 kb/s, 1k tbn, 1k tbc
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
frame=   57 fps=0.0 q=-1.0 Lsize=     214kB time=00:00:56.00 bitrate=  31.2kbits/s
video:208kB audio:0kB global headers:0kB muxing overhead 2.745583%

[vpi]

Output file that does not seek correctly

[cehoyos]

Given that 41a097a is a predecessor of bd60349 your newer test does not make much sense.

Please reopen the ticket if the problem is still reproducible with current git head.

[vpi]

6bfb304 resolves this issue for us (and another video issue we were having).

However, 6bfb304 has introduces a new set of warnings that we were not getting before for audio files. We will submit a separate ticket for that.