Re: libv4lconvert: fix RGB32 conversion

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 07/19/2014 03:38 PM, Hans Verkuil wrote:
> On 07/19/2014 02:37 PM, Hans de Goede wrote:
>> Hi,
>>
>> On 07/19/2014 09:18 AM, Hans Verkuil wrote:
>>> The RGB32 formats start with an alpha byte in memory. So before calling the
>>> v4lconvert_rgb32_to_rgb24 or v4lconvert_rgb24_to_yuv420 function skip that initial
>>> alpha byte so the src pointer is aligned with the first color component, since
>>> that is what those functions expect.
>>>
>>> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
>>>
>>> diff --git a/lib/libv4lconvert/libv4lconvert.c b/lib/libv4lconvert/libv4lconvert.c
>>> index cea65aa..e4aa54a 100644
>>> --- a/lib/libv4lconvert/libv4lconvert.c
>>> +++ b/lib/libv4lconvert/libv4lconvert.c
>>> @@ -1132,6 +1132,7 @@ static int v4lconvert_convert_pixfmt(struct v4lconvert_data *data,
>>>   			errno = EPIPE;
>>>   			result = -1;
>>>   		}
>>> +		src++;
>>
>> Hmm what about bgr versus rgb, since those are mirrored, maybe the location of
>> the alpha byte is mirrored to, and we should only do the src++ for one of them ?
> 
> Uh, that's what I do. Only for the RGB32 pixformats does the src have to be
> increased by one. The BGR32 pixformats have the alpha at the end, so there is
> no need to increment src.

Duh, I did not look closely enough, so the original patch is:

Acked-by: Hans de Goede <hdegoede@redhat.com>

Feel free to push it.

Regards,

Hans