For small images, nvjpegEncodeYUV and nvjpegEncodeImage return NVJPEG_STATUS_INTERNAL_ERROR. I ran a test for all output formats and subsampling factors, this stops being a problem when both image dimensions are 25 or larger. The same error seems to appear for all backends. While this is a reasonable limitation of a GPU-accelerated decoder, is it a known issue? If so, can it be added to the documentation? If not, I can make a bug report.
I filed a bug report Log in | NVIDIA Developer and made a reproducer https://github.com/nolmoonen/nvjpeg-bug-report-2.