[FFmpeg-devel] [PATCH 2/2] swscale: add unscaled conversion from yuv420p to p010

[Timo Rothenpieler]

On 9/3/2016 3:15 PM, Carl Eugen Hoyos wrote:
> 2016-09-03 14:54 GMT+02:00 Timo Rothenpieler <timo at rothenpieler.org>:
> 
>>>> +                AV_WL16(&dstUV[2*x  ], (t | (t << 8)) & 0xFFC0);
>>>
>>> Why is "& 0xFFC0" necessary?
>>> (Same below.)
>>
>> Because P010 expects the 10 bits in the 10 most significant bit.
>> I'm not 100% sure if the other 6 bits are undefined or 0, but all the
>> other implementations treat them as zeroes.
> 
> I suggest to remove this.

At least https://technet.microsoft.com/pt-br/library/bb970578.aspx
describes the lower 6 bits as set to 0, so leaving them in an undefined
state might have unintended sideeffects.