[MEncoder-users] mencoder is unable to select libmpeg2/mpeg12 decoder

[Cristian Manea]

Correction: the OS I'm using is not Debian Stable, it is Debian Testing, and
I installed MEncoder from Debian Multimedia repository.

On Sun, Sep 25, 2011 at 11:29 PM, Cristian Manea <
cristian.manea348 at gmail.com> wrote:

> I use this command to encode interlaced DVD to progressive H.264 with
> MEncoder:
>
> mencoder vobfile.vob -vf crop=704:464:12:8,yadif,hqdn3d=2:1:2 -nosound -ovc
>> x264 -x264encopts
>> crf=18.0:preset=slower:tune=film:profile=high:level_idc=30:threads=auto -of
>> rawvideo -o encodedstream.264
>
>
> The problem is that when I open vob files or dvd titles with mplayer and
> mencoder, ffmpeg is selected to decode the mpeg2 stream, but in the output
> it says that this codec is not compatible with the source format:
>
> Could not find matching colorspace - retrying with -vf scale...
>> Opening video filter: [scale]
>> The selected video_out device is incompatible with this codec.
>> Try appending the scale filter to your filter list,
>> e.g. -vf spp,scale instead of -vf spp.
>
>
> So I tried selecting another codec using "-vc mpeg12" in mplayer first, and
> it wasn't able to start playback. I then tried "-vfm libmpeg2 -vc mpeg12"
> and it didn;t work either. The output in both cases was:
>
>  MPlayer SVN-r33953 (C) 2000-2010 MPlayer Team
>>
>> Playing dvd://5.
>> libdvdread: Encrypted DVD support unavailable.
>> libdvdread: Attempting to use device /dev/loop0 mounted on /mnt/iso for
>> CSS authentication
>> libdvdread: Could not open input: Permission denied
>> libdvdread: Can't open /dev/loop0 for reading
>> libdvdread: Device /dev/loop0 inaccessible, CSS authentication not
>> available.
>> There are 6 titles on this DVD.
>> There are 1 angles in this DVD title.
>> audio stream: 0 format: ac3 (stereo) language:  aid: 128.
>> number of audio channels on disk: 1.
>> number of subtitles on disk: 0
>> MPEG-PS file format detected.
>> VIDEO:  MPEG2  720x480  (aspect 2)  29.970 fps  8000.0 kbps (1000.0
>> kbyte/s)
>> ==========================================================================
>> Forced video codec: mpeg12
>> Opening video decoder: [libmpeg2] libmpeg2 MPEG 1/2 Video decoder
>> Selected video codec: [mpeg12] vfm: libmpeg2 (MPEG-1 or 2 (libmpeg2))
>> ==========================================================================
>> ==========================================================================
>> Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
>> AUDIO: 48000 Hz, 2 ch, s16le, 192.0 kbit/12.50% (ratio: 24000->192000)
>> Selected audio codec: [ffac3] afm: ffmpeg (FFmpeg AC-3)
>> ==========================================================================
>> AO: [alsa] 48000Hz 2ch s16le (2 bytes per sample)
>> Starting playback...
>> Movie-Aspect is 1.33:1 - prescaling to correct movie aspect.
>> VO: [xv] 720x480 => 720x540 Planar YV12
>> MPlayer interrupted by signal 11 in module: decode_video
>> - MPlayer crashed by bad usage of CPU/FPU/RAM.
>>   Recompile MPlayer with --enable-debug and make a 'gdb' backtrace and
>>   disassembly. Details in
>> DOCS/HTML/en/bugreports_what.html#bugreports_crash.
>> - MPlayer crashed. This shouldn't happen.
>>   It can be a bug in the MPlayer code _or_ in your drivers _or_ in your
>>   gcc version. If you think it's MPlayer's fault, please read
>>   DOCS/HTML/en/bugreports.html and follow the instructions there. We can't
>> and
>>   won't help unless you provide this information when reporting a possible
>> bug.
>>
>>
> I'm using Debian Stable and I have a package called "libmpeg2-4" that was
> already installed. What seems to be the problem with this mpeg2 decoder ? Is
> there another decoder that I should select when encoding DVD's to H.264 with
> MEncoder ? I don't know of any other mpeg2 decoder, but I would like to
> solve that incompatibility: "The selected video_out device is incompatible
> with this codec"
>