[FFmpeg-trac] #499(undetermined:new): H264 resolution change in flv not supported

[FFmpeg]

#499: H264 resolution change in flv not supported
-------------------------------------+-------------------------------------
               Reporter:  cehoyos    |                  Owner:
                   Type:  defect     |                 Status:  new
               Priority:  normal     |              Component:
                Version:  git-       |  undetermined
  master                             |               Keywords:
             Blocked By:             |               Blocking:
Reproduced by developer:  0          |  Analyzed by developer:  0
-------------------------------------+-------------------------------------
 I will attach a Flash sample that contains a h264 stream with a resolution
 change (320x256 -> 720x576). The sample is said to play with Flash, a
 similar mp4 sample decodes fine with ffmpeg.
 For the attached sample, FFmpeg only shows artefacts from the moment of
 the resolution change on.
 {{{
 $ ffmpeg -i resolutionchange.flv -qscale 2 -an out.avi
 ffmpeg version N-32788-g394781a, Copyright (c) 2000-2011 the FFmpeg
 developers
   built on Sep 22 2011 14:49:18 with gcc 4.5.3
   configuration: --cc=/usr/local/gcc-4.5.3/bin/gcc
   libavutil    51. 17. 0 / 51. 17. 0
   libavcodec   53. 16. 0 / 53. 16. 0
   libavformat  53. 12. 0 / 53. 12. 0
   libavdevice  53.  4. 0 / 53.  4. 0
   libavfilter   2. 43. 2 /  2. 43. 2
   libswscale    2.  1. 0 /  2.  1. 0
 [flv @ 0x12b6780] Estimating duration from bitrate, this may be inaccurate

 Seems stream 0 codec frame rate differs from container frame rate: 48.00
 (48/1) -> 25.00 (25/1)
 Input #0, flv, from 'resolutionchange.flv':
   Duration: N/A, start: 0.002000, bitrate: N/A
     Stream #0.0: Video: h264 (High), yuv420p, 320x256 [SAR 1024:1024 DAR
 5:4], 25 tbr, 1k tbn, 48 tbc
     Stream #0.1: Audio: aac, 44100 Hz, stereo, s16
 [buffer @ 0x12be940] w:320 h:256 pixfmt:yuv420p tb:1/1000000 sar:1024/1024
 sws_param:
 [mpeg4 @ 0x12be120] Invalid pixel aspect ratio 1024/1024, limit is 255/255
 reducing
 Output #0, avi, to 'out.avi':
   Metadata:
     ISFT            : Lavf53.12.0
     Stream #0.0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 320x256 [SAR
 1:1 DAR 5:4], q=2-31, 200 kb/s, 25 tbn, 25 tbc
 Stream mapping:
   Stream #0.0 -> #0.0 (h264 -> mpeg4)
 Press [q] to stop, [?] for help
 [h264 @ 0x12bcbc0] left block unavailable for requested intra4x4 mode -1
 at 0 1
 [h264 @ 0x12bcbc0] error while decoding MB 0 1, bytestream (48355)
 [h264 @ 0x12bcbc0] concealing 320 DC, 320 AC, 320 MV errors
 [h264 @ 0x12bcbc0] concealing 233 DC, 233 AC, 233 MV errors
 [h264 @ 0x12bcbc0] concealing 293 DC, 293 AC, 293 MV errors
 [h264 @ 0x12bcbc0] concealing 258 DC, 258 AC, 258 MV errors
 [h264 @ 0x12bcbc0] Reference 2 >= 2
 [h264 @ 0x12bcbc0] error while decoding MB 9 2, bytestream (3556)
 [h264 @ 0x12bcbc0] concealing 320 DC, 320 AC, 320 MV errors
 [h264 @ 0x12bcbc0] Reference 3 >= 3
 [h264 @ 0x12bcbc0] error while decoding MB 11 1, bytestream (16377)
 [h264 @ 0x12bcbc0] concealing 320 DC, 320 AC, 320 MV errors
 [h264 @ 0x12bcbc0] concealing 192 DC, 192 AC, 192 MV errors
 [h264 @ 0x12bcbc0] Reference 5 >= 5

 ...

 [h264 @ 0x12bcbc0] error while decoding MB 14 2, bytestream (9337)
 [h264 @ 0x12bcbc0] concealing 315 DC, 315 AC, 315 MV errors
 [h264 @ 0x12bcbc0] concealing 215 DC, 215 AC, 215 MV errors
 [h264 @ 0x12bcbc0] AVC: nal size 17728
 [h264 @ 0x12bcbc0] no frame!
 Error while decoding stream #0.0
 frame=  285 fps=  0 q=2.0 Lsize=    2102kB time=00:00:11.92
 bitrate=1444.5kbits/s
 video:2089kB audio:0kB global headers:0kB muxing overhead 0.610160%
 }}}
 No useful warning is shown that the decoding will fail or has failed.

-- 
Ticket URL: <https://avcodec.org/trac/ffmpeg/ticket/499>
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