[x264-devel] Generating H264 for iPad?

[Jason Garrett-Glaser]

On Tue, Feb 21, 2012 at 2:20 PM, Reindl Harald <h.reindl at thelounge.net> wrote:
>
>
> Am 21.02.2012 23:18, schrieb Hadmut Danisch:
>> Hi,
>>
>> I just ran into a particular problem with ffmpeg and H264 encoding, and
>> was forwarded by package maintainers to this mailing list.
>>
>>
>> I'd like to convert several videos into H264, most of them into
>> 1280x720, currently testing bitrates between 700k and 2000k. I'd like to
>> use the generated videos on Computers, network DLNA streamers, and
>> mobile devices such as iPad.
>>
>> The problem I've ran into:
>>
>> The videos I generate with ffmpeg (e.g. ffmpeg -i sample_in.mp4 -vcodec
>> libx264 -vpre superfast -b 2000k -acodec copy -s 1280x720 -aspect 16:9
>> sample_out.mp4 ) can be viewed without any problem on computers and my
>> network streamers, but not on my iPad. The iPad drops frames, can't
>> generate full screens, completely freezes the screen. This does not
>> happen if I reduze the resolution. The problem is obviously that the
>> iPad does not have enough computation power.
>
> you need baseline profile!
>
> iphones are refusing videos with main-profile completly

This is false; Apple has marketed Main Profile support for years and,
in reality, iPads actually support High Profile.

Jason