#15: Initial I-frame in ogg/theora file is not decoded ----------------------+---------------------- Reporter: cehoyos | Owner: michael Type: defect | Status: new Priority: normal | Component: avformat Version: git | Keywords: Blocked By: | Blocking: Reproduced: 0 | Analyzed: 0 ----------------------+---------------------- Attached sample plays fine with vlc and mplayer -demuxer ogg -vc theora, it shows initial artefacts with ffmpeg (and ffplay and mplayer -demuxer lavf -vc theora) that disappear after a few seconds. {{{ ffmpeg -loglevel 99 -v 9 -i bad\ thumbnail\ from\ this\ video.ogv -an -qscale 2 out.avi FFmpeg version git-N-28581-g4fa0e24, Copyright (c) 2000-2011 the FFmpeg developers built on Mar 23 2011 06:04:48 with gcc 4.5.2 configuration: --cc=/usr/local/gcc-4.5.2/bin/gcc --enable-gpl libavutil 50. 40. 0 / 50. 40. 0 libavcodec 52.114. 0 / 52.114. 0 libavformat 52.103. 0 / 52.103. 0 libavdevice 52. 3. 0 / 52. 3. 0 libavfilter 1. 76. 0 / 1. 76. 0 libswscale 0. 12. 0 / 0. 12. 0 [NULL @ 0x11ed650] Probed with size=2048 and score=100 [theora @ 0x11f2250] Theora bitstream version 30201 [ogg @ 0x11ed650] max_analyze_duration reached Input #0, ogg, from 'bad thumbnail from this video.ogv': Duration: 00:00:19.06, start: 0.000000, bitrate: 417 kb/s Stream #0.0, 0, 1/1: Data: skeleton Stream #0.1, 152, 1/30: Video: theora, yuv420p, 480x270 [PAR 1:1 DAR 16:9], 1/30, 30 fps, 30 tbr, 30 tbn, 30 tbc Stream #0.2, 286, 1/44100: Audio: vorbis, 44100 Hz, mono, s16, 70 kb/s Metadata: ENCODER : ffmpeg2theora-0.24 new_video_stream: video_codec_tag: 0 [buffer @ 0x13b94e0] w:480 h:270 pixfmt:yuv420p [setdar @ 0x13b9990] a:16/9 [setdar @ 0x13b9990] w:480 h:270 -> dar:16/9 par:1/1 [theora @ 0x11f2250] Theora bitstream version 30201 Output #0, avi, to 'out.avi': Metadata: ISFT : Lavf52.103.0 Stream #0.0, 0, 1/30: Video: mpeg4, yuv420p, 480x270 [PAR 1:1 DAR 16:9], 1/30, q=2-31, 200 kb/s, 30 tbn, 30 tbc Stream mapping: Stream #0.1 -> #0.0 Press ctrl-c to stop encoding [theora @ 0x11f2250] vp3: first frame not a keyframe frame= 560 fps= 0 q=2.0 Lsize= 2032kB time=19.07 bitrate= 873.1kbits/s video:2013kB audio:0kB global headers:0kB muxing overhead 0.958895% }}} -- Ticket URL: <http://avcodec.org/trac/ffmpeg/ticket/15> FFmpeg <http://ffmpeg.org> FFmpeg issue tracker