Very insightful, but is x265 really that bad? If you’re willing to wait, does slower presets help?
I tested NVENC, X265, and DaVinci Resolve Studio’s H265 encoder.
x265 was best by far. What more am I missing on?
I tested NVENC, X265, and DaVinci Resolve Studio’s H265 encoder.
x265 was best by far. What more am I missing on?
Now things like NVENC are even worse in terms of compression. Any GPU accelerated encoder trades compression efficiency for speed. Even x265 with the slowest presets will demolish any GPU encoder in terms of compression, including the MainConcept paid one when it's run in GPU-accelerated mode. This is unfortunately not explained in GUIs like Adobe tools. They just have a checkbox or dropdown to select GPU acceleration, but don't mention that it's not just acceleration - a different algorithm will be used that can't achieve the best compression.
GPU accelerated compression can still be very useful for scenarios where you need speed (e.g. have a deadline) or just don't care about quality (e.g. will publish it only on social media where it will be recompressed anyway). However when you have time to wait and want top quality, the slowest CPU-only code path will always win.
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[1] One good public resource is the Moscow State University page http://www.compression.ru/video/codec_comparison/index_en.ht... -- They do regular comparisons of various codecs and some results are available for free. A bit in HTML form and more in some of the PDFs. Deeper insights are unfortunately paid.
Seems strange that we have so much compute power in GPU, but no algorithms to use it well for encodes