Change #286511

Comments

avfilter/vf_scale_cuda: support resizing during YUV<->RGB conversion
Resizing is done on the RGB side: YUV to RGB conversion converts at the
visible input size before scaling, RGB to YUV conversion converts after
scaling at the output size. Every scaling pass then works on a single
packed plane and reuses the generic RGB kernels, and the conversion
kernels are reused with a float RGB side.

The RGB intermediates hold normalized floats, so filter overshoot and
out of gamut colors are not clipped before the scaler rounds and clamps
once. As conversion and filtering are linear, the result matches
scaling on the YUV side, apart from rounding and the chroma upsampling
of the conversion kernels.

Resizing during conversion always uses the generic filters with the
selected interp_algo, with nearest using point sampling weights.
Conversion without resizing keeps using the direct conversion kernels.

Assisted-By: Claude Opus 5.5

Changed files

• doc/filters.texi
• libavfilter/vf_scale_cuda.c
• libavfilter/vf_scale_cuda.cu
• tests/fate/filter-video.mak
• tests/ref/fate/filter-scale_cuda-resize-bgra-nv12-down
• tests/ref/fate/filter-scale_cuda-resize-bgra-p010-up
• tests/ref/fate/filter-scale_cuda-resize-bgra-yuv444p-h
• tests/ref/fate/filter-scale_cuda-resize-crop-nv12-bgra
• tests/ref/fate/filter-scale_cuda-resize-nv12-bgra-up
• tests/ref/fate/filter-scale_cuda-resize-p010-bgra-down
• tests/ref/fate/filter-scale_cuda-resize-step-p010
• tests/ref/fate/filter-scale_cuda-resize-yuv420p-rgba-w