[FFmpeg-devel] [PATCH] add uuid box to MP4 to make h.264 play on iPod

[Baptiste Coudurier]

Hi guys,

Michael Niedermayer wrote:
> On Sat, Feb 23, 2008 at 04:34:19PM +0000, M?ns Rullg?rd wrote:
>> Michael Niedermayer <michaelni at gmx.at> writes:
>>
>>> On Sat, Feb 23, 2008 at 12:25:16PM +0000, M?ns Rullg?rd wrote:
>>>> Mark Himsley <mark at mdsh.com> writes:
>>>>
>>>>> Attached patch adds new -f <format> of ipod264. When using that format
>>>>> the file is created as with mp4 format but with the addition of the
>>>>> uuid required for the file to be transferred from iTunes to an iPod
>>>>> that plays "Low Complexity" Baseline Profile H.264. Tested syncing
>>>>> with iPod Touch.
>>>> I don't like inventing new, fake formats for each and every
>>>> variation.  
>>> I dont like it either but its easy, simple and doesnt really add hard to
>>> maintain code ...
>>> Also changing the fake formats to some other system is seperate of adding
>>> new ones IMHO.
>> The more new ones are add, the more work there will be if we want to
>> switch to something better.
> 
> Most of the code is just stuff like track->mode == MODE_IPOD/MOV/...
> that would not change at all if we switch from fake formats to something
> else.
> 
> 
>>>> Things like this should be passed as flags/parameters to
>>>> the mp4 muxer instead.  If there is no way of doing that currently,
>>>> lavf should be extended to support it.
>>> This causes problems, because the following is stored per AVOutputFormat:
>>> * default codecs
>>> * list of supported codecs as well as their codec tags
>> This could be solved by moving those lists into an AVSubFormat (or
>> whatever) struct, along with a name and whatever else might be useful.
>> Each AVOutputFormat would then have a list of AVSubFormat (the first
>> being the default).
> 
> This could be done but it would primarely increase complexity, so iam against
> it. The fake formats are ugly but besides this feeling which i certainly feel
> as well i dont see any real disadvantage from them.
> 

Well, I already proposed something like a flavour field in
AVOutputFormat, it could be used for 3g2/psp/ipod and will avoid the
Makefile/allformats.c cruft, also could be used for amv2 (swf variant),
and yes, a generic solution is needed, I think it would be nice to be
set automatically according to extension too (.3g2)

Besides, I prefer -f ipod instead of -f ipod264, if we ever choose this
solution.

-- 
Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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