[FFmpeg-user] Decode to BGR24 avi
Paul B Mahol
onemda at gmail.com
Tue Jan 29 12:18:20 CET 2013
On 1/29/13, Timo Stjernberg <timo.infradex at gmail.com> wrote:
> Hello.
>
> I am returning this issue back via the actual mailing list, since posting
> via nabble.com doesn't seem to work right. Refer to
> http://ffmpeg-users.933282.n4.nabble.com/Decode-to-BGR24-raw-AVI-td4653855.htmlfor
> the original thread.
>
> There seems to be a disagreement between FFmpeg and VirtualDub of what
> uncompressed bgr24 raw avi really is. I can tell this already by looking at
> file sizes that they produce from the same video but PSNR & other metrics
> tell me they're definitely not the same video.
>
> I have done extensive testing on different videos with ffmpeg and so I
> decided to set this test up for you guys to figure out what is going south
> on bgr24 raw avi's.
>
> All example video files are accessible at http://videotimo.fi/ffmpeg/
>
> TEST PHASE 1:
> We start with a raw original avi that has been built from PNG frames with
> VirtualDub (sintel_raw_original.avi). We make a rawvideo -pix_fmt bgr24
> copy of it with ffmpeg to find out that even when there should be no
> difference between input and output, the files are not the same in size.
> (sintel_ffmpeg_raw2raw.avi)
>
> Console output:
>
> ffmpeg -i G:\Testivideot\sintel_raw_original.avi -vcodec rawvideo -pix_fmt
> bgr24 sintel_ffmpeg_raw2raw.avi:
>
> ffmpeg version N-47062-g26c531c Copyright (c) 2000-2012 the FFmpeg
> developers
> built on Nov 25 2012 12:21:26 with gcc 4.7.2 (GCC)
> configuration: --enable-gpl --enable-version3 --disable-pthreads
> --enable-runt
> ime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r
> --enable-libass -
> -enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libfreetype
> --enab
> le-libgsm --enable-libmp3lame --enable-libnut --enable-libopenjpeg
> --enable-libo
> pus --enable-librtmp --enable-libschroedinger --enable-libspeex
> --enable-libtheo
> ra --enable-libutvideo --enable-libvo-aacenc --enable-libvo-amrwbenc
> --enable-li
> bvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid
> --ena
> ble-zlib
> libavutil 52. 9.100 / 52. 9.100
> libavcodec 54. 77.100 / 54. 77.100
> libavformat 54. 37.100 / 54. 37.100
> libavdevice 54. 3.100 / 54. 3.100
> libavfilter 3. 23.102 / 3. 23.102
> libswscale 2. 1.102 / 2. 1.102
> libswresample 0. 17.101 / 0. 17.101
> libpostproc 52. 2.100 / 52. 2.100
> Input #0, avi, from 'G:\Testivideot\sintel_raw_original.avi':
> Duration: 00:00:01.21, start: 0.000000, bitrate: 234514 kb/s
> Stream #0:0: Video: rawvideo, bgr24, 848x480, 24 tbr, 24 tbn, 24 tbc
> Output #0, avi, to 'd:\sintel_ffmpeg_raw2raw.avi':
> Metadata:
> ISFT : Lavf54.37.100
> Stream #0:0: Video: rawvideo, bgr24, 848x480, q=2-31, 200 kb/s, 24 tbn,
> 24 t
> bc
> Stream mapping:
> Stream #0:0 -> #0:0 (rawvideo -> rawvideo)
> Press [q] to stop, [?] for help
> frame= 21 fps=0.0 q=0.0 size= 25048kB time=00:00:00.87
> bitrate=234508.5kbits
> frame= 29 fps=0.0 q=0.0 Lsize= 34589kB time=00:00:01.20
> bitrate=234497.3kbit
> s/s
> video:34582kB audio:0kB subtitle:0 global headers:0kB muxing overhead
> 0.018011%
> ----------------------------------------------------------------------------------
> TEST PHASE 2:
>
> We encode the raw original to mpeg2 (sintel_ffmpeg_raw2mpeg2.avi). The
> encode goes smoothly.
>
> Console output:
>
> ffmpeg -i sintel_raw_original.avi -vcodec mpeg2video -b:v 2000k
> sintel_ffmpeg_raw2mpeg2.avi:
>
> ffmpeg version N-47062-g26c531c Copyright (c) 2000-2012 the FFmpeg
> developers
> built on Nov 25 2012 12:21:26 with gcc 4.7.2 (GCC)
> configuration: --enable-gpl --enable-version3 --disable-pthreads
> --enable-runt
> ime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r
> --enable-libass -
> -enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libfreetype
> --enab
> le-libgsm --enable-libmp3lame --enable-libnut --enable-libopenjpeg
> --enable-libo
> pus --enable-librtmp --enable-libschroedinger --enable-libspeex
> --enable-libtheo
> ra --enable-libutvideo --enable-libvo-aacenc --enable-libvo-amrwbenc
> --enable-li
> bvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid
> --ena
> ble-zlib
> libavutil 52. 9.100 / 52. 9.100
> libavcodec 54. 77.100 / 54. 77.100
> libavformat 54. 37.100 / 54. 37.100
> libavdevice 54. 3.100 / 54. 3.100
> libavfilter 3. 23.102 / 3. 23.102
> libswscale 2. 1.102 / 2. 1.102
> libswresample 0. 17.101 / 0. 17.101
> libpostproc 52. 2.100 / 52. 2.100
> Input #0, avi, from 'G:\Testivideot\sintel_raw_original.avi':
> Duration: 00:00:01.21, start: 0.000000, bitrate: 234514 kb/s
> Stream #0:0: Video: rawvideo, bgr24, 848x480, 24 tbr, 24 tbn, 24 tbc
> Output #0, avi, to 'd:\sintel_ffmpeg_raw2mpeg2.avi':
> Metadata:
> ISFT : Lavf54.37.100
> Stream #0:0: Video: mpeg2video (mpg2 / 0x3267706D), yuv420p, 848x480,
> q=2-31
> , 2000 kb/s, 24 tbn, 24 tbc
> Stream mapping:
> Stream #0:0 -> #0:0 (rawvideo -> mpeg2video)
> Press [q] to stop, [?] for help
> frame= 19 fps=0.0 q=4.0 size= 302kB time=00:00:00.70
> bitrate=3494.3kbits/s
> frame= 29 fps=0.0 q=3.5 Lsize= 408kB time=00:00:01.16
> bitrate=2865.0kbits/
> s
> video:402kB audio:0kB subtitle:0 global headers:0kB muxing overhead
> 1.554130%
> ------------------------------------------------------------------------------
> TEST PHASE 3:
>
> We decode the mpeg2 video back to bgr24 raw avi
> (sintel_ffmpeg_mpeg2toRAW.avi). The result is not at all what I would
> expect. The decoded video has one frame more than the original. Therefore
> if I compare the original and the decoded video for PSNR or MAE, the
> calculations don't match at all. Only if I strip the first frame from the
> decoded avi, the calculations seem valid.
>
> Console output:
> ffmpeg -i D:\sintel_ffmpeg_raw2mpeg2.avi -vcodec rawvideo -pix_fmt bgr24
> d:\sintel_ffmpeg_mpeg2toRAW.avi
>
> ffmpeg version N-47062-g26c531c Copyright (c) 2000-2012 the FFmpeg
> developers
> built on Nov 25 2012 12:21:26 with gcc 4.7.2 (GCC)
> configuration: --enable-gpl --enable-version3 --disable-pthreads
> --enable-runt
> ime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r
> --enable-libass -
> -enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libfreetype
> --enab
> le-libgsm --enable-libmp3lame --enable-libnut --enable-libopenjpeg
> --enable-libo
> pus --enable-librtmp --enable-libschroedinger --enable-libspeex
> --enable-libtheo
> ra --enable-libutvideo --enable-libvo-aacenc --enable-libvo-amrwbenc
> --enable-li
> bvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid
> --ena
> ble-zlib
> libavutil 52. 9.100 / 52. 9.100
> libavcodec 54. 77.100 / 54. 77.100
> libavformat 54. 37.100 / 54. 37.100
> libavdevice 54. 3.100 / 54. 3.100
> libavfilter 3. 23.102 / 3. 23.102
> libswscale 2. 1.102 / 2. 1.102
> libswresample 0. 17.101 / 0. 17.101
> libpostproc 52. 2.100 / 52. 2.100
> Input #0, avi, from 'D:\sintel_ffmpeg_raw2mpeg2.avi':
> Metadata:
> encoder : Lavf54.37.100
> Duration: 00:00:01.21, start: 0.000000, bitrate: 2766 kb/s
> Stream #0:0: Video: mpeg2video (Main) (mpg2 / 0x3267706D), yuv420p,
> 848x480
> [SAR 1:1 DAR 53:30], 24 fps, 24 tbr, 24 tbn, 48 tbc
> Output #0, avi, to 'd:\sintel_ffmpeg_mpeg2toRAW.avi':
> Metadata:
> ISFT : Lavf54.37.100
> Stream #0:0: Video: rawvideo, bgr24, 848x480 [SAR 1:1 DAR 53:30],
> q=2-31, 20
> 0 kb/s, 24 tbn, 24 tbc
> Stream mapping:
> Stream #0:0 -> #0:0 (mpeg2video -> rawvideo)
> Press [q] to stop, [?] for help
> frame= 29 fps=0.0 q=0.0 Lsize= 34589kB time=00:00:01.25
> bitrate=226681.3kbit
> s/s
> video:34582kB audio:0kB subtitle:0 global headers:0kB muxing overhead
> 0.018293%
> ---------------------------------------------------------------------------------
>
> This extraneous frame does seem to appear at least with VC-1 and mpeg2
> encode/decode process. Still, something is done very differently on all
> bgr24 raw avi decodes because I still have to run all the raw avi decodes
> through VirtualDub after ffmpeg before feeding the test videos to the PSNR
> calculator.
>
> Additionally, Microsoft Expression Encoder 4 doesn't seem to understand the
> raw avi produced by ffmpeg at all.
If you open bug report and upload working raw avi (with first say 10
frames) and provide link
to uploaded contet in same bug report than someone could take look at
that bug report
and at least provide some kind of workaround.
>
> Anybody had any similar incidents? Anybody that can clarify any of this?
> What am I doing wrong?
> _______________________________________________
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> ffmpeg-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
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