[FFmpeg-devel] [PATCH] libavfilter: vf_scale: Properly take in->color_range into account

[Martin Storsjö]

On Sun, 6 Mar 2022, Michael Niedermayer wrote:

> On Sat, Mar 05, 2022 at 11:33:15PM +0200, Martin Storsjö wrote:
>> On Fri, 4 Mar 2022, Michael Niedermayer wrote:
>>
>>> On Thu, Mar 03, 2022 at 02:06:45PM +0200, Martin Storsjö wrote:
>>>> While swscale can be reconfigured with sws_setColorspaceDetails,
>>>> the in/out ranges also need to be set before calling
>>>> sws_init_context, otherwise the initialization might choose
>>>> fastpaths that don't take the ranges into account.
>>>>
>>>> Therefore, look at in->color_range too, when deciding on whether
>>>> the scaler needs to be reconfigured.
>>>>
>>>> Add a new member variable for keeping track of this, for being
>>>> able to differentiate between whether the scale filter parameter
>>>> "in_range" has been set (which should override whatever the input
>>>> frame has set) or whether it has been configured based on the
>>>> latest frame (which should trigger reconfiguring the scaler if
>>>> the input frame ranges change).
>>>>
>>>> Signed-off-by: Martin Storsjö <martin at martin.st>
>>>> ---
>>>> To test this (without risking running many conflicting swscale
>>>> filters in one filter pipeline), we'd need to be able to tag
>>>> the incoming raw yuv data with colorspace and range without setting
>>>> the in_color_matrix and in_range options on the scale filter.
>>>>
>>>> When using the rawvideo demuxer, the pixel format is set via the
>>>> ffmpeg -pix_fmt option, but there's no corresponding option for
>>>> setting color matrix or range for it.
>>>> ---
>>>>  libavfilter/vf_scale.c | 13 +++++++++++++
>>>>  1 file changed, 13 insertions(+)
>>>
>>> This changes the output for:
>>> ffmpeg -i tickets/524/AVCI50.mov   -vframes 3 file-avci50dec.nut
>>> ffmpeg -i tickets/4493/AVCI100.mov -vframes 3 file-avci100dec.nut
>>>
>>> https://samples.ffmpeg.org/ffmpeg-bugs/trac/ticket524/
>>>
>>> Is that intended ?
>>>
>>> - 233903 file-avci100dec.nut
>>> - 383853 file-avci50dec.nut
>>> + 196558 file-avci100dec.nut
>>> + 333893 file-avci50dec.nut
>>
>> Looks like these source files have full range content; for any data with
>> full range input, this patch makes sure it uses the right intended
>> conversion through swscale. So yes, I guess it's expected that these
>> conversions change.
>
> patch ok then

Pushed, thanks.

// Martin