[vlc-devel] [PATCH 1/8] decoder: let the decoder tell how many pictures it needs in the pool

[Rémi Denis-Courmont]

Le tiistaina 28. heinäkuuta 2020, 12.08.34 EEST Steve Lhomme a écrit :
> This is necessary for pools that attach buffers/surfaces to the pictures
> from the decoder so that the picture wait is done at the decoder_t level
> and not inside each decoder module (which can't be easily canceled
> otherwise).
> 
> For now no module provides the proper size so the behavior is unchanged.

There are two ways to do it:

1) (This patch) The decoder tells the owner, and the owner takes care of it. 
This only works for normal (i.e. software) picture buffers.
2) The decoder allocates its own pool of the correct size. This works for both 
normal and opaque picture buffers.

And based on that, we need to support the second mechanism anyway, so the first 
mechanism seems rather vain. The second mechanism is also more in line with 
the earlier design directions/decisions.


In any case, this is putting the cart before the horses. The bigger problem is 
how the filters, splitter and display tell how many (extra) buffers they need. 
We can't just decree that they'll have their own pool for extra buffers, as 
that would imply memory copying from decoder pool buffers to other pool buffers.

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