I didn't upload all the waveform screenshots, but if you look at a 10bit waveform (it's 1024 pixels "tall", each value 0-1023 is represented). It's left unflagged (because range flag can cause some programs to compress the range) "orig_crf1unflagged.mp4" attached is a 2048x1080 "double wide" ramp pattern yuv420p10 AVC, 1 frame, each value is repeated, 0,0,1,1,2,2. For example if I convert to 8bit in avs or vpy without dither, then encode - it's about the same size (~5kb), but has gaps in the data (show below in a waveform) Ī program that does not apply dither (or maybe you can disable it in handbrake), would still have gaps in the data, banding. Also the encoding settings can change the size (for example xmediarecode didn't use same settings as default cli, file size was >2x the size). Container overhead can be that large (Check the elementary stream if you're doing that). And for a simple gradient, it is lossless (You can re-encode with CRF1 and PSNR is infinity)īe careful about just looking at the "filesize" only especially when it's just 1 frame, ~5Kb. "Lossless mode" isn't as widely supported in other programs, NLE's etc. Could you still please post your 10bit gradient test video here ? It's easy enough, even for beginners, to measure filesize and check for 10bit output in MediaInfo.Īlso why not use the encoder Lossless mode (x265 -lossless, x264 crf=0) ? I check end to end tests for various workflows (e.g. OK, I can imagine that the difficulty may in fact be analyzing the result rather than generating a gradient. Note on "real" content, the "ballooning" size won't be so drastic, but it's still suboptimal if you start with 10bit content Handbrake output >10x the size mainly because of the dithering, and gaps in the data (0,4,8) when you examine it. Handbrake "10bit" 2nd generation x265 crf 1 76kb Handbrake "10bit" 2nd generation x264 crf 1 70kb Xmediarecode 10bit x264 2nd generation crf 1 (same settings) 5kb X264cli 10bit 2nd generation crf 1 5kb (output PSNR actually lossless CRF1) I think some GUI's like staxrip canĠ-1023 gradient original produced at crf1 5kb Xmedia can preserve 10bit if you set it up correctly but I see no way of preserving the HDR metadata automatically. When you test - it dithers the intermediate stage (functions like noise to "hide" the banding), so it doesn't look as bad on a gradient as no dither - but the filesize balloons up because of the dithering Handbrake/vidcoder definitely uses an 8bit intermediate stage this is well documented. If there is an 8bit step, you will get gaps in the data such as 0,4,8, instead of 0,1,2,3,4,6,7,8, which of course results in more banding, less accuracy, worse compression
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