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VideoPlane cached width, height and buffer_size when created, but read the frame's data pointer live. A plane made before apply_cropping() then paired the shifted pointer with the old size, so bytes(plane), memoryview(plane), update() and DLPack export read or wrote past the buffer. Recompute the geometry whenever the frame's dimensions, data pointer or linesize change. Also document that for hardware frames and 1-bit formats FFmpeg applies only the right and bottom crop, leaving crop_left and crop_top set.
Reject a crop when the two crops on an axis would leave no pixels, the same rule av_frame_apply_cropping() uses. Without this, nonsense values reached hardware filters such as scale_cuda, scale_vt and scale_vulkan, which read the crop fields without checking them. Zero is always allowed so the fields can be cleared.
av_frame_copy_props() copies crop_* onto the reformatted frame. They are in source pixels, so they still hold after a pixel format change but not after a resize, where they can exceed the new dimensions. Clear them when the size changes.
WyattBlue
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Follow-up to #2496.
apply_cropping()paired the shifted pointer with the old size.bytes(plane),memoryview(plane),update()and DLPack export then read or wrote past the buffer (reproduced as SIGBUS with a guard page). The geometry is now recomputed whenever the frame's dimensions, data pointer or linesize change. Also documents that FFmpeg only applies the right and bottom crop for hardware frames and 1-bit formats.av_frame_apply_cropping()uses, so nonsense values can't reach hardware filters (scale_cuda,scale_vt,scale_vulkan,amf) that read the fields unchecked.reformat()resizes a frame.av_frame_copy_props()copies them onto the output; they still hold after a pixel format change but not after a resize, where they can exceed the new dimensions.