![]() ![]() In other words, is the following statement correct: If I encode a video with H.264 with a CRF of N, do I get the same visual result if I encode the same video with H.265 with a CRF of N+5, independent of N? Or does that formula only apply for N=28 and N=23, respectively, since this is the example the FFMPEG H. ![]() So I have learned that a H.265 CRF 28 should produce roughly the same visual results as a H.264 CRF 23.ĭoes that mean that a H.265 CRF 22 should produce roughly the same visual results as a H.264 CRF 17? ![]() The default is 28, and it should visually correspond to libx264 video at CRF 23, but result in about half the file size. ffmpeg -i input.mp4 -c:v libx265 -vtag hvc1 -c:a copy output.mp4 Convert 4k (h.264) to 1080 (h.265) Downscaling + Change in compression codec ffmpeg -i input.mp4 -c:v libx265 -vtag hvc1 -vf scale1920:1080 -crf 20 -c:a copy output.mp4 Options Explained -i input file name or file path -c:v libx265 -vtag hvc1 selecting compression. configure -enable-debug and follow the ffmpeg bugreporting guidelines. In the section about the CRF value:Ĭonsider 17 or 18 to be visually lossless or nearly so it should look the same or nearly the same as the input but it isn't technically lossless.įurthermore, in FFMPEG's H.265 documentation, in the section about the CRF value: If it is a crash, then compile x265 with. I know that this term may be misleading, but I have taken it from FFMPEG's H.264 documentation. The Compilation Guides show you how to do that. Getting ffmpeg with libx265 support ffmpeg needs to be built with the -enable-gpl -enable-libx265 configuration flags and requires x265 to be installed on your system. I have decided to give FFMPEG's H.265 encoder a try, and now would like to know which CRF value I should use to get "visually lossless" results. See HWAccelIntro for information on supported hardware H.265/HEVC encoders. I am trying to shrink some videos from 1920x1080 to 1280x720 and to achieve a reasonable compromise between video quality and file size. You should see the incoming connection from ffmpeg show up like this: Set up the Raspberry Pi.
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