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7th April 2021, 20:55 | #441 | Link | |
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All my VMAF results are based on VMAF 2.0.0 (model 0.6.1) and resolution is unchanged, original resolution for all. I found an Iris Xe HEVC/AVC comparison from Intel btw: https://dgpu-docs.intel.com/devices/...des/media.html |
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7th April 2021, 21:34 | #442 | Link | |
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That said, these suggest a generally competent encoder for high speed use (presumably why --preset medium was the top option). If you used x265 with --preset slower --tune psnr, x265 likely would win by a fair margin. |
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7th April 2021, 21:51 | #443 | Link |
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That being said, Intel didn't use the highest quality preset in this (there is another image with quality preset). But of course x265 slower would win in almost every case unless their Ubuntu FFMPEG environment is better than my Windows QSVEnc environment which I don't think it is.
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8th April 2021, 17:12 | #444 | Link |
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I could test a GTX 1660 Super next week, it's already running on the current 7th gen Nvenc generation, I'm curious how it compares to Iris Xe. Is there a settings tutorial somewhere? Is it correct that 5 bframes is the maximum number of bframes on Nvenc?
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8th April 2021, 20:14 | #445 | Link | |
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An always-interesting question is where the crossover point in speed/quality is between HW and SW encoders. A key use of GPU encoders is for game streaming, where even 25% CPU utilization would hurt FPS in a lot of games. |
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8th April 2021, 22:51 | #447 | Link | |
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Although faster presets do use less psychovisual optimization, and mainly make choices based on SAD, which maps to PSNR better... |
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8th April 2021, 23:04 | #448 | Link | |
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Left side of the chart: Bit-rate savings (higher is better). 13.7% bitrate saving for x265 slow over medium and 11.0% higher bitrate required for very fast preset over medium. VME quality is the best Quicksync preset. |
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10th April 2021, 00:29 | #450 | Link |
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I have finished my first GTX 1660 test from my last video sample. I have tried lots of different settings and this is the best I could find (b-frame ref middle gave me a nice score boost).
Code:
Intel Demo Clip 1080p VMAF PSNR SSIM VQM speed bitrate Quicksync H265 Iris Xe CQP best 91.76 41.85 0.9748 0.790 67 fps 2438 kbit NVENC H265 GTX 1660S CQP best 90.62 41.28 0.9699 0.885 150 fps 2439 Kbit x265 (Staxrip 2.1.9.0) i7-1165G7 CRF slow 93.20 41.90 0.9754 0.800 8 fps 2430 kbit i7-1165G7 CRF medium 91.05 41.35 0.9744 0.861 19 fps 2440 Kbit i7-1165G7 CRF very fast 89.99 40.97 0.9726 0.894 32 fps 2440 Kbit x264 (Staxrip 2.1.9.0) i7-1165G7 CRF slow 89.38 40.21 0.9693 0.974 30 fps 2425 Kbit https://drive.google.com/file/d/1onL...ew?usp=sharing Metric scores are a mixed bag, respectable VMAF and PSNR scores but not that good at VQM and especially SSIM metrics. Subjective frame to frame comparison it's obvious detail preservation is a lot worse compared to Iris Xe (VME/GPU) and x265. |
10th April 2021, 15:35 | #451 | Link |
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Blender Open Movie from here: https://forum.doom9.org/showpost.php...&postcount=423
Code:
HERO - Blender Open Movie VMAF speed bitrate Quicksync H265 (27.20.100.9316) Iris Xe CQP FF best 86.56 550 fps 199 kbit Iris Xe CQP FF balanced 85.66 850 fps 201 Kbit Iris Xe CQP FF speed 76.25 1550 fps 200 Kbit Iris Xe CQP best 88.59 167 fps 200 kbit Iris Xe CQP balanced 87.18 280 fps 201 Kbit Iris Xe CQP speed 86.22 520 fps 200 Kbit NVENC H265 (470.14) GTX 1660S CQP best 84.52 430 fps 200 Kbit GTX 1660S CQP default 83.55 990 fps 201 Kbit GTX 1660S CQP performance 79.22 1130 fps 200 Kbit x265 (Staxrip 2.1.9.0) i7-1165G7 CRF slower 90.25 8 fps 200 Kbit i7-1165G7 CRF slow 88.18 34 fps 200 kbit i7-1165G7 CRF medium 85.72 56 fps 200 Kbit i7-1165G7 CRF very fast 83.36 73 fps 200 Kbit x264 (Staxrip 2.1.9.0) i7-1165G7 CRF slower 75.37 81 fps 200 Kbit Disabled b-adapt is better for this video. Turing CQP cannot reach Iris Xe CQP quality, subjective and objective the difference is large. Turing has two downsides, only 5 bframes versus 16 bframes on Iris Xe and there is no GPU equivalent mode which is more flexible than a fully fixed function solution, however even the FF mode from Iris Xe looks better. It might look different with CBR vs CBR which I haven't tried. That said, the H265 CQP results from Turing are really good for a hardware encoder, something like x265 fast-faster with extremely fast encoding times, the CQP quality from Iris Xe is just insane. Last edited by Yups; 10th April 2021 at 15:47. |
10th April 2021, 20:03 | #453 | Link | |
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CQP with custom offset offers higher quality than ICQ, this old Quicksync bitrate method overview is still valid:
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For a basic user ICQ is easier to handle, there is just one global setting and that's it. Furthermore ICQ does not really scale over 5 bframes (16 bframes can be worse than 5 at low bitrate) whereas CQP scales really good beyond 5 bframes even at low bitrate. Here I did include both ICQ and CQP: https://forum.doom9.org/showpost.php...&postcount=369 On Iris Xe it automatically uses ctu 64 (Gen 9 ctu 32), this can't be changed at the moment. Tskip and SAO are also enabled on Tigerlake which I can't disable. Reference frames best leave it auto, with 16 bframes+bpyramid Intel sets it to 6 reference frames, I've tried 8 reference frames but there is no improvement. |
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17th April 2021, 23:05 | #454 | Link |
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CQP best runs ~5% faster with Intels new driver build 9466 on Iris Xe.
I was searching for CQP improvements and noticed that 14 and 15 bframes offers slightly better scores at a slightly lower bitrate on Iris Xe over 16 bframes which I was using. This is tested on Intel Demo Clip and Blender Open Movie low bitrate. 13 bframes and lower gradually decreases bitrate efficiency, it's a big degradation from 14 to 13 bframes. 14 bframes is a tiny bit better than 15. For better context: Code:
Intel Demo Clip 1080p VMAF PSNR SSIM VQM speed bitrate Quicksync H265 27.20.100.9466 Iris Xe CQP best 16 bframes 91.76 41.85 0.9748 0.790 73 fps 2438 kbit Iris Xe CQP best 14 bframes 91.98 41.96 0.9754 0.780 74 fps 2426 Kbit NVENC H265 GTX 1660S CQP best 90.62 41.28 0.9699 0.885 150 fps 2439 Kbit x265 (Staxrip 2.1.9.0) i7-1165G7 CRF slow 93.20 41.90 0.9754 0.800 8 fps 2430 kbit i7-1165G7 CRF medium 91.05 41.35 0.9744 0.861 19 fps 2440 Kbit i7-1165G7 CRF very fast 89.99 40.97 0.9726 0.894 32 fps 2440 Kbit x264 (Staxrip 2.1.9.0) i7-1165G7 CRF slow 89.38 40.21 0.9693 0.974 30 fps 2425 Kbit Bitrate goes down from 2438 to 2426 and scores go up, it's a clear win. |
18th April 2021, 21:51 | #455 | Link | |
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18th April 2021, 23:57 | #457 | Link |
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The point is you obviously don't have any proof for your claim. I just pointed out what I think about some dubious claims from that article.
If you believe that just using fixed qp's is going to create efficient encoding in terms of file size/picture quality... well, I'm not going to persuade you otherwise. We all have our specific needs in regards to using encoders. Keep believing in your vmaf/psnr/ssim numbers. |
19th April 2021, 15:49 | #458 | Link | ||
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Nonsense. Subjective and objective CQP is clearly better than ICQ, I told this more than once and I have uploaded several samples. If you don't agree prove it! If you don't believe in vmaf/psnr/ssim numbers download the sample or ask for the upload if I didn't upload any wanted sample, I'm always checking for subjective quality my results. I don't force you to believe any numbers. Bframes scaling with CQP is way better than with ICQ or CBR/VBR on Iris Xe. CBR/VBR 7 bframes are best and on ICQ there is no real improvement over 5 bframes. With CQP it scales up to 14-16 bframes, this is one reason why ICQ can't reach CQP. This is something you can't know because you are obviously clueless. About fixed CQP, I mean depending on the bitrate/quality target different quantization parameter are required, this is no different to any other constant rate factor. I don't understand your problem to be honest, I mean it's super easy on Intel (easier than on Nvidia). |
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20th April 2021, 12:51 | #459 | Link | ||
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Here, read about about etiquette on this forum. Quote:
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20th April 2021, 18:44 | #460 | Link |
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Both of you can be correct. Usually RCF mode means better quality for the same bitrate, but if Intel's ICQ is broken it might reduce too much, like hevc-aq does in x265. Can't really conclude anything, without comparing clips of several scenes, one scene is not enough. Hand-picker quantitizer might be better for one scene, but it won't be an efficient way to encode hour long video.
Also, one frame might look better on CQ and other would be better on ICQ, so it depends on what are we comparing. Do you see quality difference in running clip or just a single random frame you chose. Last edited by Tenkei; 20th April 2021 at 18:48. |
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