[vlc-devel] [PATCH] [RFC] picture: use the offset to increase the visible lines/pitch

[Rémi Denis-Courmont]

Le 2015-09-10 19:19, Steve Lhomme a écrit :
> On Thu, Sep 10, 2015 at 5:55 PM, Rémi Denis-Courmont 
> <remi at remlab.net> wrote:
>> Le 2015-09-10 18:50, Steve Lhomme a écrit :
>>>
>>> Since we don't use the x/y offset when copying planes (plane_t is 
>>> missing
>>> these fields), we may miss some pixels.
>>
>>
>> So?
>
> So it's missing some pixels that should be displayed.

I got that, but I don't get how that justifies corrupting the visible 
lines count and pitch.

> Either we add
> the offset information in plane_t (unlikely as we need to check all
> the code using plane_t).

I agree that would be impractical. But...

> Or we consider the offset adds a visible area.

That corrupts used values. It breaks some video outputs. I am not sure 
if it does not also break some filters.

> It should be safe as it only applies to plane_t data when
> manipulating pixels.

I don't see how that could be safe, unless the values were not used at 
all (in which case, removing them would have been the obvious solution).

-- 
Rémi Denis-Courmont
http://www.remlab.net/