[FFmpeg-devel] [PATCH V2 1/2] lavf/vc1test: fix vc1test can't probe some RCV file.

[mypopy at gmail.com]

On Fri, Oct 12, 2018 at 10:35 PM Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
>
> 2018-10-12 15:41 GMT+02:00, Jun Zhao <mypopydev at gmail.com>:
> > case 1:
> > use the hexdump -C SMM0005.rcv get:
> >                      size              skip (size - 4)
> >                       |                        |
> >                       V                        V
> > 00000000  18 00 00 c5 05 00 00 00  4d f1 0a 11 00 e0 01 00
> > 00000010  00 d0 02 00 00 0c 00 00  00 88 13 00 00 c0 65 52
> >                          ^
> >                        |
> >                    size + 16
> > case 2:
> > same the command for SMM0015.rcv get:
> >                     size
> >                       |
> >                       V
> > 00000000  19 00 00 c5 04 00 00 00  41 f3 80 01 40 02 00 00
> > 00000010  d0 02 00 00 0c 00 00 00  00 00 00 10 00 00 00 00
> >                       ^
> >                     |
> >                  size + 16
> >
> > There are different the RCV file format for VC-1, vc1test
> > just handle the case 2 now, this fix will support the case 1.
>
> Both with and without your patch, I get identical output from
> FFmpeg's decoder for both SSM0015.rcv and SMM0005.rcv.
> What exactly is your patch supposed to change?
>
> $ md5sum SMM0005.rcv
> abd0fa5ec90d44f7b4865c6930d65ff2  SMM0005.rcv
> $ md5sum SSM0015.rcv
> 21a0281f83b7f2e99a048b180dd3347f  SSM0015.rcv

In my test clips, I get md5 like this
$ md5sum SMM0005.rcv
39eb225dbfafacea3e3737deba789530  SMM0005.rcv
$ md5sum SMM0015.rcv
78e45e50079e143e69f69d677c37ac3b  SMM0015.rcv
>
>
> The following does not change:
>
> $ ffmpeg -i SMM0005.rcv -f crc -
> ffmpeg version N-92147-gf85fa10 Copyright (c) 2000-2018 the FFmpeg developers
>   built with gcc 6.4.0 (GCC)
>   configuration: --enable-gpl --enable-gnutls --enable-libxml2
>   libavutil      56. 19.101 / 56. 19.101
>   libavcodec     58. 32.100 / 58. 32.100
>   libavformat    58. 18.104 / 58. 18.104
>   libavdevice    58.  4.105 / 58.  4.105
>   libavfilter     7. 33.100 /  7. 33.100
>   libswscale      5.  2.100 /  5.  2.100
>   libswresample   3.  2.100 /  3.  2.100
>   libpostproc    55.  2.100 / 55.  2.100
> Input #0, vc1test, from 'SMM0005.rcv':
>   Duration: 00:00:01.00, bitrate: 7472 kb/s
>     Stream #0:0: Video: wmv3 (Main), yuv420p, 720x480, 24 fps, 24 tbr,
> 24 tbn, 24 tbc
> Stream mapping:
>   Stream #0:0 -> #0:0 (wmv3 (native) -> rawvideo (native))
> Press [q] to stop, [?] for help
> Output #0, crc, to 'pipe:':
>   Metadata:
>     encoder         : Lavf58.18.104
>     Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p,
> 720x480, q=2-31, 99532 kb/s, 24 fps, 24 tbn, 24 tbc
>     Metadata:
>       encoder         : Lavc58.32.100 rawvideo
> SMM0005.rcv: Input/output error
>     Last message repeated 1 times
> CRC=0xe3b2671c
> frame=   24 fps=0.0 q=-0.0 Lsize=       0kB time=00:00:01.00 bitrate=
>  0.1kbits/s speed=14.8x
> video:12150kB audio:0kB subtitle:0kB other streams:0kB global
> headers:0kB muxing overhead: unknown
>
> What exactly is your patch supposed to improve?
>
> Thank you, Carl Eugen
>
> (05 looks different here.)