[vlc-devel] [RFC PATCH 0/9] Fixing A/V dejitter with high latency devices

[Steve Lhomme]

On 2020-12-10 20:14, Thomas Guillem wrote:
> 
> 
> On Thu, Dec 10, 2020, at 18:35, Francois Cartegnie wrote:
>> Le 10/12/2020 à 18:10, Thomas Guillem a écrit :
>>>
>>> 2/ Add a callback to the master clock that will fetch the aout delay.
>>> This callback could be triggered by the vout before displaying a frame.
>>
>> That means trigger condition is generally when converting the first non
>> master stream timestamp ?
> 
> Indeed, so if the vout is early (audio not ready), the time_get() callback won't return a valid delay and the vout will use the monotonic clock. Then it will wait for the frame display time with vlc_clock_Wait(). This waiting function should take care of polling the last delay before returning.

Shouldn't it just return INT64_MAX (which should have a proper 
name/define) ? In that case the vout considers it's paused.

IMO, contrary to what is done now, the first frame should not be 
displayed ASAP but when its time has come. A file could start with 5s of 
audio and then the video starts. There's no reason the first frame 
should be shown when the source intentionally didn't have something to 
display.