Matroska video format

[Baho Utot]

On 05/25/16 03:42, Eduardo Morras via freebsd-questions wrote:
> On Tue, 24 May 2016 20:12:23 -0400
> Baho Utot <baho-utot at columbus.rr.com> wrote:
>
>> On 05/24/16 07:32, Eduardo Morras via freebsd-questions wrote:
>>> On Sun, 22 May 2016 20:42:41 -0400
>>> Baho Utot <baho-utot at columbus.rr.com> wrote:
>>>
>>>> I would like to play a Matroskavisoe using vlc, Is this possible?
>>> vlc supports mkv container format.
>>>
>>>> It starts to play but the picture goes in and out of grey
>>> It's a video codec problem, not mkv.
>>>
>>> If it happens once or mixed with other defects, it's (>90%) a tiny
>>> corruption on video file.
>>>
>>> If it happens too often and in the same way (you see 1-2 pictures
>>> and goes grey, 1-2 pictures and again grey repeteadly) then the
>>> video was codified with a feature vlc can't decode. Upgrade vlc and
>>> it's dependence libraries or use other viewer (ffplay from ffmepg)
>>> that uses other library (for H264 you have OpenH264, ffmpeg, x264,
>>> etc.. and not all of them supports all H264 subformats/modes).
>>>
>>> If you transcode it with ffmpeg check first ffmpeg/ffplay can play
>>> it nicely.
>> It does indeed appear as a codec problem, windog 7 will play the
>> video just fine.
> To know the codec information, use (assuming you have ffmpep installed)
>
> %ffprobe -hide_banner input_file
>
> Input #0, avi, from 'input_file':
>    Metadata:
>      encoder         : VirtualDubMod 1.5.10.2 (build 2540/release)
>    Duration: 01:58:56.04, start: 0.000000, bitrate: 1676 kb/s
>      Stream #0:0: Video: mpeg4 (Advanced Simple Profile) (XVID / 0x44495658), yuv420p, 704x292 [SAR 1:1 DAR 176:73], 1022 kb/s, 25 fps, 25 tbr, 25 tbn, 25 tbc
>      Stream #0:1: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, 5.1(side), fltp, 320 kb/s
>      Stream #0:2: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, 5.1(side), fltp, 320 kb/s
>
> At Stream #0 you can see video codec (mp4), the profile used (Avanced Simple) and codec implementation (xvid)
>
> These kind of problem occurs when codec use other standard profiles not implemented in decoder or non standard profiles options.
>
>> I tried to transcode it but it did not work
> Transcode needs to play it, if the codec library don't support the feature used by creator codec, obtained output file will show the same problems.
>
> Install or reinstall ffmpeg from ports, configure it with SDL support (if not, ffplay is not created) and
>
> a) #cd /usr/ports/multimedia/ffmpeg
> b) #make config
> c) Check SDL, x264, if they're not checked
> d) UnCheck OpenH264, if it's checked
> e) # make install
>
> Use '%ffplay filename' to play the video.
>
>> I am now trying to find out which codec are availiable and if I have
>> them installed.
> To show the codecs (decoders) available by your ffmpeg compiled you can use:
>
> %ffmpeg -decoders
>
> and to show everything your compiled ffmpeg can do:
>
> %ffmpeg --help full
>
> adding a new codec needs reconfiguration and recompilation.
>
> P.S. If you config ffmepg port and don't know what were the default ffmpeg port configuration, do '#make rmconfig' to reset it.
>
> HTH
>
> ---   ---
> Eduardo Morras <emorrasg at yahoo.es>
> _______________________________________________
> freebsd-questions at freebsd.org mailing list
> https://lists.freebsd.org/mailman/listinfo/freebsd-questions
> To unsubscribe, send any mail to "freebsd-questions-unsubscribe at freebsd.org"

I think my issue has something to do with this:

[swscaler @ 0x81604d000] Warning: data is not aligned! This can lead to 
a speedloss

Anyway I have rebuilt ffmpeg and enabled SDL, it plays but with the 
above error


  Thanks