[FFmpeg-devel] [FFmpeg-devel-irc] IRC log for 2010-03-28

[Måns Rullgård]

Baptiste Coudurier <baptiste.coudurier at gmail.com> writes:

> On 03/30/2010 07:16 PM, M?ns Rullg?rd wrote:
>> Baptiste Coudurier<baptiste.coudurier at gmail.com>  writes:
>>
>>> On 03/30/2010 07:11 PM, M?ns Rullg?rd wrote:
>>>> Alexander Strange<astrange at ithinksw.com>   writes:
>>>>
>>>>> There are some streamcopy bugs (copying audio from flv to mp3
>>>>> failing with non-monotone timestamps when mp3 can't have timestamps
>>>>> anyway) reported but not fixed, it might be discouraging more. Of
>>>>> course, I never managed to look into them myself...
>>>>
>>>> Streamcopy of anything out of mkv always fails in the same way.
>>>> Trivially hacked up tools to simply dump packets to a file do the
>>>> right thing...
>>>
>>> That is just false. It fails in some specific cases, and only with
>>> H.264 and B-pyramid AFAIK.
>>
>> I guess those specific cases are all mkv files on my hard disk.  And
>> in "anything" I also include audio.
>
> What codec ?

Yesterday it was AAC.  I've encountered it with MP3 and AC3 too.

> The problem with mkv is that it doesn't contain dts, to remux to mp4,

I was trying to extract the audio as a raw elementary stream, no
timestamps needed.

> you _absolutely_ need dts. To compute correct dts you need the correct
> delay.
>
> Then you have mkv storing timestamps per block, you have to
> interpolate the timestamps per frame to remux it to mp4 by example.

So do that.

> Don't imply "streamcopying" _online_ is easy as saying it, please.
> Offline is _easier_ but is also not realistic when dealing with huge files.

Online, offline?

-- 
M?ns Rullg?rd
mans at mansr.com