[x264-devel] How to set level programmatically

[Sergio Garcia Murillo]

El 24/05/2013 18:38, BugMaster escribió:
> On Fri, 24 May 2013 12:38:51 +0200, Sergio Garcia Murillo wrote:
>> El 24/05/2013 12:32, Jason Garrett-Glaser escribió:
>>> On Fri, May 24, 2013 at 1:47 AM, Sergio Garcia Murillo
>>> <sergio.garcia.murillo at gmail.com> wrote:
>>>> +1
>>>>
>>>> Some conferencing equipment matches the level in the SPS with the
>>>> profile-level-id negotiated via SDP and reject it if they don't match (even
>>>> if the h264 stream comply with the level constrains). So currently I have to
>>>> check all output nals for SPS ones and rewrite the value.
>>> Wouldn't it be vastly easier to just set i_level_idc? This seems like
>>> orders of magnitude more effort than is necessary...
>>>
>> Would love it, but in my tests, the i_level_idc is only used to apply
>> the constrains to the encoding, but the profile-level-id set in the SPS
>> is calculated internally and may not match the i_level_idc.
>
> What? In libx264 i_level_idc doesn't apply any constrains to the
> encoding. It is used only as tag and written directly to level_idc
> field in SPS. The only exception is special value 9 for baseline/main
> where it used to signal 1b level which changed internally to
> level_idc=11 and constraint_set3_flag=1.


Upss.. sorry, my fault.. I jumped to quickly. I had problems fixing the 
other parts of the profile-level-id (probably the constrains part, don't 
recall for sure), but the level was ok.

Best regards
Sergio