hwdownload+hwupload produced output with no video. Switch back to hwmap reverse=1 to VAAPI (then hwmap to QSV). Now that scale_opencl is gone and the shader processes NV12 natively, the OpenCL frames remain in the VAAPI-linked pool so reverse=1 is viable. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>