[x264-devel] X264 recovery_frame_cnt is out of spec

[Chris Brien]

On 16.09.2010 11:36, Jason Garrett-Glaser wrote:
> On Thu, Sep 16, 2010 at 2:38 AM, Chris Brien<chris.brien at tandberg.com>  wrote:
>> On 15.09.2010 20:04, Jason Garrett-Glaser wrote:
>>>
>>> On Wed, Sep 15, 2010 at 8:16 AM, Chris
>>> Brien<chris.brien at tandberg.com>    wrote:
>>>>
>>>> The H.264 spec section D.2.7 says "recovery_frame_cnt shall be in
>>>> the range of 0 to MaxFrameNum-1, inclusive".
>>>
>>> That's rather lame.  Seems like we'll have to make MaxFrameNum larger
>>> when intra refresh is on then.
>>
>> It is a bit lame. But then its meaning isn't "count this many frames until
>> the picture is refreshed", but rather "this is what frame_num will be when
>> the picture is refreshed",
>
> Does that mean if the current frame num is 10, and it's 16 frames to
> refresh, we need to set recovery_frame_cnt to 25?

No, recovery_frame_cnt is still 15 if it takes 16 frames to refresh. 
Sorry I wasn't clear, but what I meant was that "the picture will be 
refreshed when frame_num is equal to (current frame_num + 
recovery_frame_cnt) % MaxFrameNum". So if the current frame_num is 10 
and it takes 16 frames refresh, recovery_frame_cnt is 15, and the 
picture will be refreshed when frame_num is 9 (with MaxFrameNum=16).

Chris