[FFmpeg-devel] [PATCH] lavfi: add colorkey_opencl filter

[Mark Thompson]

On 11/04/2019 03:42, Cld fire wrote:
> On Wed, Apr 10, 2019 at 6:10 PM Mark Thompson <sw at jkqxz.net> wrote:
>>> +        // Make sure the input is a format we support
>>> +        if (fmt != AV_PIX_FMT_ARGB &&
>>> +            fmt != AV_PIX_FMT_RGBA &&
>>> +            fmt != AV_PIX_FMT_ABGR &&
>>> +            fmt != AV_PIX_FMT_BGRA &&
>>> +            fmt != AV_PIX_FMT_NONE
>>
>> Why NONE here?
>>
> 
> It was in the list of formats that the CPU filter said it supported and,
> after briefly looking around, it appeared
> that it was used as a generic special case of some kind (?). There's no
> documentation on the enum variant,
> though, so wasn't able to figure out its exact meaning. Judging by your
> question, perhaps it is irrelevant for
> HW frames?

You mean the list at <http://git.videolan.org/?p=ffmpeg.git;a=blob;f=libavfilter/vf_colorkey.c;h=3d65e59d42c6fa480e00f4b7ab079677bcac876a;hb=HEAD#l113>?  AV_PIX_FMT_NONE (-1) is the invalid enum AVPixelFormat value used as the sentinel for the end of the list passed to ff_make_format_list().

- Mark