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Old 16th July 2019, 17:38   #1  |  Link
Ischemia24
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Highest quality to file size ratio

I didn't see anything about this in the guides or FAQ and googling also hasn't turned up the specific information I'm looking for, so I'm asking here: How can I use H.265 to achieve the highest quality to file size ratio?

A year or two ago I found this post by Ma in the main HEVC thread. Based on that I've been using these Handbrake settings.

1080p
MKV format, 1920x1080, no filters, 10-bit H.265, constant framerate same as source, very slow preset, no encoder tune, auto-profile, 2-pass, 1500 bitrate, Extra Options: rc-lookahead=120:bframes=12:ref=6:subme=7
If it is a dark video then: rc-lookahead=120:bframes=12:ref=6:subme=7:aq-mode=3

720p (only listing what's different here and for subsequent resolutions)
1280x720, 760 bitrate

480p
854x480, 360 bitrate

360p
640x360, 300 bitrate

These are a starting point, and I've had to adjust the bitrate or try CRF instead, depending on the source files. But I've noticed that others have outdone me when it comes to the quality to file size ratio. It seems there should be a better set of options to start with, or I'm missing something in terms of what settings I should know to try to tweak in different scenarios.

I've seen these types of threads before and contributed to them, and they usually have answers like "just find what's right for you", but I would like to at least hear what baseline settings others use and what are the prime candidates for settings to tweak for those that value quality to file size as I do.

Last edited by Ischemia24; 17th July 2019 at 13:18.
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Old 16th July 2019, 19:54   #2  |  Link
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My advice would be to seriously analyze how much time disk space is really worth to you.

We're at the point where you can buy a 8 TB (~ 7250 GiB in real disk space) for $150 ... that's 0.02$ per GB.

At 3 mbps, you're looking at ~ 22 MB per minute or 1.4 GB per hour ...

If you're gonna spend maybe 2-3 hours per one hour of encoding you should at least use a higher bitrate, maybe something like 8-10mbps VBR for 1080p and 4-8 mbps VBR for 720p ... if you end up with around 4-6 GB for a 2h movie, you're still looking at less than 0.1$ in disk space cost.

// also hmm.. you joined nov 2016 but today's your first post?

// ps... also checked the other forum post you mentioned.. hope you realized he used a cartoon for tests... real motion video, bluray with grain etc will behave differently.. make sure you understand why he uses some settings there.
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Old 16th July 2019, 22:48   #3  |  Link
Ischemia24
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Quote:
Originally Posted by mariush View Post
My advice would be to seriously analyze how much time disk space is really worth to you.

We're at the point where you can buy a 8 TB (~ 7250 GiB in real disk space) for $150 ... that's 0.02$ per GB.

At 3 mbps, you're looking at ~ 22 MB per minute or 1.4 GB per hour ...
I run an ITX media server, and I don't have a lot of room for expandability. But I recently upgraded it to a 3900X, so I am finally in a position to throw a lot of CPU power at H.265 encoding.

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Originally Posted by mariush View Post
If you're gonna spend maybe 2-3 hours per one hour of encoding you should at least use a higher bitrate, maybe something like 8-10mbps VBR for 1080p and 4-8 mbps VBR for 720p ... if you end up with around 4-6 GB for a 2h movie, you're still looking at less than 0.1$ in disk space cost.
Most of the time the settings I cited in the original post work pretty well for me. But I've seen examples where I'm clearly beaten in quality to file size. I want to know how to improve. Actually, part of that is how to leverage the 3900X, because I started three instances of Handbrake doing 360p and 480p encodes and the CPU is not fully utilized. Maybe should be its own post.

Quote:
Originally Posted by mariush View Post
also hmm.. you joined nov 2016 but today's your first post?

ps... also checked the other forum post you mentioned.. hope you realized he used a cartoon for tests... real motion video, bluray with grain etc will behave differently.. make sure you understand why he uses some settings there.
Yes, I was going to ask then what settings I should use for my goals, but I feared I hadn't done enough of my own research and held off, then forgot all about it.

I think the Big Buck Bunny movie sample he used is something that you would tune for Film if using H.264 rather than Animation. But I admit I don't know why he went with the particular settings he chose. It was just presented as "true placebo" mode for H.265 and I seized on it.
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Old 17th July 2019, 00:08   #4  |  Link
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Time to change your media server to something larger. Sorry, but that is the reality. Disk space is cheap, and it will actually cost you more in power to convert your movies, than to just store them. IE the amount it will cost in power to use your computer to "save space" by encoding, is more expensive than storing the original on a hard drive and just buying new drives when you run out of space. Especially if you care about quality in your encodes.
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Old 17th July 2019, 00:12   #5  |  Link
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Turning the nebulous concept of "quality" into a linear value that a ratio can be calculated from is a massive unsolved problem in computer vision and human visual perception. Any scale you could come up with would be specific to a given scenario.
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Old 17th July 2019, 08:10   #6  |  Link
Ischemia24
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I don't feel like the substance of my question is being addressed. I'm not looking to re-encode my entire library. Just a few things, and most new titles I add. I get that quality is difficult to quantify in the context of video encoding, but we do have methods for it, however imperfect.

Any input on encoding settings?
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Old 17th July 2019, 09:12   #7  |  Link
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Quote:
Originally Posted by Ischemia24 View Post
I don't feel like the substance of my question is being addressed. I'm not looking to re-encode my entire library. Just a few things, and most new titles I add. I get that quality is difficult to quantify in the context of video encoding, but we do have methods for it, however imperfect.

Any input on encoding settings?
Then lets assume that encoding time is pretty much irelevant to the discussion (which sounds crazy to me, but okey). What excactly are you not pleased with? You are talking about examples were you are beaten, how were they beaten? Have you encoded the same content at the same bitrate and compared them? As far as I can see, you are already pretty much throwing everything x265 has to offer at the encode, you can add something like --no-sao and --deblock -1:-1 if you want better detail and noise retention, but other then that, there is not really much more to do, you are already well beyond the diminishing returns point when it comes to compression gains at the cost of cpu cycles.

And for the "Highest quality to file size ratio" part, this is exactly what crf is good for, just start with a baseline crf of 18 or something and increase it until you hit your sweetspot between visual fidelity and size (cause only you can decide at what point you are pleased with quality), at that point you will have found the "best" "quality to fie size ratio". This will also effect your encoding settings, are you looking at maxing out compression with low bitrates and will accept a lot of quality degradation, or should it be close to visually transparent? Cause for example, --no-sao and --deblock -1:-1 is great for the later case, but no that great for the first one.

Last edited by excellentswordfight; 17th July 2019 at 12:09.
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Old 17th July 2019, 12:35   #8  |  Link
Ischemia24
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Originally Posted by excellentswordfight View Post
You are talking about examples were you are beaten, how are you beaten? Have you encoded the same content at the same bitrate and compared them? As far as I can see, you are already pretty much throwing everything x265 has to offer at the encode, you can add something like --no-sao and --deblock -1:-1 if you want better detail and noise retention, but other then that, there is not really much more to do, you are already well beyond the diminishing returns point when it comes to compression gains at the cost of cpu cycles.

And for the "Highest quality to file size ratio" part, this is exactly what crf is good for, just start with a baseline crf of 18 or something and increase it until you hit your sweetspot between visual fidelity and size (cause only you can decide at what point you are pleased with quality), at that point you will have found the "best" "quality to fie size ratio". This will also effect your encoding settings, are you looking at maxing out compression with low bitrates and will accept a lot of quality degradation, or should it be close to visually transparent? Cause for example, --no-sao and --deblock -1:-1 is great for the later case, but no that great for the first one.
I figured I shouldn't be specific, but, it seems common that the release group PSArips put out something that looks better and is smaller than my encodes. And for a specific example, a release group (individual?) who goes by JoyBell released two seasons of Dollhouse at ~1200 kbps 1080p that look better than most of my 1500 kbps 1080p encodes.

I appreciate the input regarding no-sao and deblock -1:-1, thank you.

I can't see the encoding settings PSArips use, but -- actually, I can see the settings on the Dollhouse episodes. Here's one:

Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L4@High
Codec ID : V_MPEGH/ISO/HEVC
Duration : 50 min 17 s
Bit rate : 1 200 kb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 10 bits
Bits/(Pixel*Frame) : 0.024
Stream size : 432 MiB (81%)
Writing library : x265 2.8+19-bcdc610cf5f0:[Windows][MSVC 1914][64 bit] 10bit
Encoding settings : cpuid=1111039 / frame-threads=3 / numa-pools=8 / wpp / no-pmode / no-pme / no-psnr / ssim / log-level=2 / input-csp=1 / input-res=1920x1080 / interlace=0 / total-frames=72337 / level-idc=0 / high-tier=1 / uhd-bd=0 / ref=3 / no-allow-non-conformance / no-repeat-headers / annexb / no-aud / no-hrd / info / hash=0 / no-temporal-layers / open-gop / min-keyint=23 / keyint=250 / gop-lookahead=0 / bframes=8 / b-adapt=2 / b-pyramid / bframe-bias=0 / rc-lookahead=20 / lookahead-slices=6 / scenecut=40 / radl=0 / no-intra-refresh / ctu=64 / min-cu-size=8 / no-rect / no-amp / max-tu-size=32 / tu-inter-depth=1 / tu-intra-depth=1 / limit-tu=0 / rdoq-level=1 / dynamic-rd=4.00 / ssim-rd / signhide / no-tskip / nr-intra=0 / nr-inter=0 / no-constrained-intra / strong-intra-smoothing / max-merge=2 / limit-refs=3 / no-limit-modes / me=1 / subme=2 / merange=57 / temporal-mvp / weightp / weightb / analyze-src-pics / deblock=0:0 / sao / sao-non-deblock / rd=3 / no-early-skip / rskip / no-fast-intra / no-tskip-fast / no-cu-lossless / b-intra / no-splitrd-skip / rdpenalty=0 / psy-rd=0.00 / psy-rdoq=0.00 / no-rd-refine / no-lossless / cbqpoffs=0 / crqpoffs=0 / rc=abr / bitrate=1200 / qcomp=0.60 / qpstep=4 / stats-write=0 / stats-read=2 / cplxblur=20.0 / qblur=0.5 / vbv-maxrate=12000 / vbv-bufsize=24000 / vbv-init=0.9 / ipratio=1.40 / pbratio=1.30 / aq-mode=3 / aq-strength=1.00 / cutree / zone-count=0 / no-strict-cbr / qg-size=32 / no-rc-grain / qpmax=69 / qpmin=0 / no-const-vbv / sar=0 / overscan=0 / videoformat=5 / range=0 / colorprim=2 / transfer=2 / colormatrix=2 / chromaloc=0 / display-window=0 / max-cll=0,0 / min-luma=0 / max-luma=1023 / log2-max-poc-lsb=8 / vui-timing-info / vui-hrd-info / slices=1 / no-opt-qp-pps / no-opt-ref-list-length-pps / multi-pass-opt-rps / scenecut-bias=0.05 / no-opt-cu-delta-qp / no-aq-motion / no-hdr / no-hdr-opt / no-dhdr10-opt / no-idr-recovery-sei / analysis-reuse-level=10 / scale-factor=0 / refine-intra=0 / refine-inter=0 / refine-mv=0 / limit-sao / ctu-info=0 / no-lowpass-dct / refine-mv-type=0 / copy-pic=1 / max-ausize-factor=1.0 / no-dynamic-refine / no-single-sei
Default : Yes
Forced : No

I don't know what to make of this because they've backed off some of the settings I specify, and I don't know what else they may have specified and what values are defaults. High-tier=1 seems significant, but I'm not seeing anything in the documentation about what benefits that could provide. I'm guessing it means poorer compatibility with decoders, but I'm not concerned about that.
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Old 17th July 2019, 13:08   #9  |  Link
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VMAF is a better video-quality metric than SSIM & PSNR,
https://streaminglearningcenter.com/...af-master.html
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Old 17th July 2019, 13:08   #10  |  Link
excellentswordfight
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Quote:
Originally Posted by Ischemia24 View Post
I figured I shouldn't be specific, but, it seems common that the release group PSArips put out something that looks better and is smaller than my encodes. And for a specific example, a release group (individual?) who goes by JoyBell released two seasons of Dollhouse at ~1200 kbps 1080p that look better than most of my 1500 kbps 1080p encodes.

I appreciate the input regarding no-sao and deblock -1:-1, thank you.

I can't see the encoding settings PSArips use, but -- actually, I can see the settings on the Dollhouse episodes. Here's one:

Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L4@High
Codec ID : V_MPEGH/ISO/HEVC
Duration : 50 min 17 s
Bit rate : 1 200 kb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 10 bits
Bits/(Pixel*Frame) : 0.024
Stream size : 432 MiB (81%)
Writing library : x265 2.8+19-bcdc610cf5f0:[Windows][MSVC 1914][64 bit] 10bit
Encoding settings : cpuid=1111039 / frame-threads=3 / numa-pools=8 / wpp / no-pmode / no-pme / no-psnr / ssim / log-level=2 / input-csp=1 / input-res=1920x1080 / interlace=0 / total-frames=72337 / level-idc=0 / high-tier=1 / uhd-bd=0 / ref=3 / no-allow-non-conformance / no-repeat-headers / annexb / no-aud / no-hrd / info / hash=0 / no-temporal-layers / open-gop / min-keyint=23 / keyint=250 / gop-lookahead=0 / bframes=8 / b-adapt=2 / b-pyramid / bframe-bias=0 / rc-lookahead=20 / lookahead-slices=6 / scenecut=40 / radl=0 / no-intra-refresh / ctu=64 / min-cu-size=8 / no-rect / no-amp / max-tu-size=32 / tu-inter-depth=1 / tu-intra-depth=1 / limit-tu=0 / rdoq-level=1 / dynamic-rd=4.00 / ssim-rd / signhide / no-tskip / nr-intra=0 / nr-inter=0 / no-constrained-intra / strong-intra-smoothing / max-merge=2 / limit-refs=3 / no-limit-modes / me=1 / subme=2 / merange=57 / temporal-mvp / weightp / weightb / analyze-src-pics / deblock=0:0 / sao / sao-non-deblock / rd=3 / no-early-skip / rskip / no-fast-intra / no-tskip-fast / no-cu-lossless / b-intra / no-splitrd-skip / rdpenalty=0 / psy-rd=0.00 / psy-rdoq=0.00 / no-rd-refine / no-lossless / cbqpoffs=0 / crqpoffs=0 / rc=abr / bitrate=1200 / qcomp=0.60 / qpstep=4 / stats-write=0 / stats-read=2 / cplxblur=20.0 / qblur=0.5 / vbv-maxrate=12000 / vbv-bufsize=24000 / vbv-init=0.9 / ipratio=1.40 / pbratio=1.30 / aq-mode=3 / aq-strength=1.00 / cutree / zone-count=0 / no-strict-cbr / qg-size=32 / no-rc-grain / qpmax=69 / qpmin=0 / no-const-vbv / sar=0 / overscan=0 / videoformat=5 / range=0 / colorprim=2 / transfer=2 / colormatrix=2 / chromaloc=0 / display-window=0 / max-cll=0,0 / min-luma=0 / max-luma=1023 / log2-max-poc-lsb=8 / vui-timing-info / vui-hrd-info / slices=1 / no-opt-qp-pps / no-opt-ref-list-length-pps / multi-pass-opt-rps / scenecut-bias=0.05 / no-opt-cu-delta-qp / no-aq-motion / no-hdr / no-hdr-opt / no-dhdr10-opt / no-idr-recovery-sei / analysis-reuse-level=10 / scale-factor=0 / refine-intra=0 / refine-inter=0 / refine-mv=0 / limit-sao / ctu-info=0 / no-lowpass-dct / refine-mv-type=0 / copy-pic=1 / max-ausize-factor=1.0 / no-dynamic-refine / no-single-sei
Default : Yes
Forced : No

I don't know what to make of this because they've backed off some of the settings I specify, and I don't know what else they may have specified and what values are defaults. High-tier=1 seems significant, but I'm not seeing anything in the documentation about what benefits that could provide. I'm guessing it means poorer compatibility with decoders, but I'm not concerned about that.
Are you also encoding dollhouse? If not, it doesnt make much sense to compare another source against it, the compressibility of different sources can be very different, you also dont know if the source were filtered to be able to compress better.

Also, the encode that you have sampled is by no means any special, it looks like something like this was used: --preset medium --profile main10 --bframes 8 --aq-mode 3 --sao-non-deblock --limit-sao --bitrate 1200 --vbv-maxrate 12000 --vbv-bufsize 24000. And afaik, main and high teir only effect allowed datarates @ given level, so it doesnt matter that much here, I would think that it is automatically set cause of --vbv-bufsize 24000.

Last edited by excellentswordfight; 17th July 2019 at 13:40.
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Old 17th July 2019, 14:26   #11  |  Link
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Quote:
Originally Posted by Ischemia24 View Post
I figured I shouldn't be specific, but, it seems common that the release group PSArips put out something that looks better and is smaller than my encodes. And for a specific example, a release group (individual?) who goes by JoyBell released two seasons of Dollhouse at ~1200 kbps 1080p that look better than most of my 1500 kbps 1080p encodes.
First, lets define "better". What about it makes it visually better? In what regard is it better?

Second, you can see all the settings they used. What's stopping you from trying their settings and experimenting?
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Old 17th July 2019, 18:58   #12  |  Link
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Originally Posted by excellentswordfight View Post
Also, the encode that you have sampled is by no means any special, it looks like something like this was used: --preset medium --profile main10 --bframes 8 --aq-mode 3 --sao-non-deblock --limit-sao --bitrate 1200 --vbv-maxrate 12000 --vbv-bufsize 24000.
It also seems that the psy options are turned off for some reason.
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Old 18th July 2019, 01:09   #13  |  Link
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Originally Posted by Forteen88 View Post
VMAF is a better video-quality metric than SSIM & PSNR,
https://streaminglearningcenter.com/...af-master.html
Doesn't look user friendly, but it does look like a good way to evaluate things in a relatively consistent way. I'll see if I can figure it out. Thank you Forteen88.

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Originally Posted by excellentswordfight View Post
Are you also encoding dollhouse? If not, it doesnt make much sense to compare another source against it, the compressibility of different sources can be very different, you also dont know if the source were filtered to be able to compress better.

Also, the encode that you have sampled is by no means any special, it looks like something like this was used: --preset medium --profile main10 --bframes 8 --aq-mode 3 --sao-non-deblock --limit-sao --bitrate 1200 --vbv-maxrate 12000 --vbv-bufsize 24000. And afaik, main and high teir only effect allowed datarates @ given level, so it doesnt matter that much here, I would think that it is automatically set cause of --vbv-bufsize 24000.
I admit, I am not also encoding Dollhouse. I've just been using the same settings for a long time and I determined my subjective experience of the videos with the bitrates they had beyond what I could achieve. It's eye opening that the encode settings seem so pedestrian.

Ugh, on further inspection, I do see they kind of "cheated". Filtered to be able to compress better -- I had no idea this was a thing. I see now in some release notes, "The SSIM measures the accuracy of the outputted encode verse the source. It does not reflect on the sharpness or awesomeness of the image, only how close it is to the source material. An "S##" is a score where filters where [sic] not used. "FS##" is an encode where we used filters before the encoder, usually for nasty amounts of grain, this can throw off the score usually in a positive way and we like to be clear and honest [...]". Huh. Looks like the encode settings I copied into this thread were from an episode that had been pre-filtered.

Quote:
Originally Posted by Stereodude View Post
First, lets define "better". What about it makes it visually better? In what regard is it better?

Second, you can see all the settings they used. What's stopping you from trying their settings and experimenting?
Better in this case is subjective, and drawn on all of my past experiences with the encodes I've done. It seemed to me that more detail was retained at a lower bitrate than I've ever managed. The episode[s] looked superior to what I've been able to achieve at that bitrate. What can I say? I give up easily.

I have no idea how this pre-filtering for better compression works, but I'd rather just stick to encoding settings, if I can get Handbrake to utilize the CPU effectively. If pre-filtering has real merit, then I imagine it'll eventually become a part of mainstream encoding software.

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It also seems that the psy options are turned off for some reason.
Oh, this is more than one. Psy-rd and Psy-rdoq. That makes experimentation more difficult. I would ask though, do you prefer to use one of these or both? If just one, which one? Or is there a case that merits one over the other, or both?
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Old 18th July 2019, 06:07   #14  |  Link
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Originally Posted by Ischemia24 View Post
Oh, this is more than one. Psy-rd and Psy-rdoq. That makes experimentation more difficult. I would ask though, do you prefer to use one of these or both? If just one, which one? Or is there a case that merits one over the other, or both?
I would leave the psy options as default. They will cause a lower score in those artificial measurement methods, but that's their nature as they are meant to improve subjective quality when you watch the video.
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Old 18th July 2019, 12:23   #15  |  Link
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Originally Posted by Ischemia24 View Post
I have no idea how this pre-filtering for better compression works, but I'd rather just stick to encoding settings, if I can get Handbrake to utilize the CPU effectively. If pre-filtering has real merit, then I imagine it'll eventually become a part of mainstream encoding software.
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Old 18th July 2019, 15:44   #16  |  Link
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Challenge to the psycho-visual metric school by the non psycho-visual metric theories is not bad thing for beginner. The measure stuffs is important in the context of encoding history.
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Old 22nd July 2019, 19:26   #17  |  Link
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Doesn't look user friendly, but it does look like a good way to evaluate things in a relatively consistent way. I'll see if I can figure it out. Thank you Forteen88.
VMAF is definitely the least-bad objective metric we've ever had. But it is slow and complex to use, and a lot of decisions need to be made. For example a 720p file encoded from a 720p source will give a higher score than the same file encoded from a 1080p source, since that comparison would scale up 720p to the original frame size.

And how to go from a number for every frame to some kind of title-level score isn't something well defined. A file that bounces from VMAF 50 to 90 is going to be more annoying to viewers than one that's a consistent 70, although both would have the same per-title score. The harmonic mean per GOP or as a 10 second rolling average might be good.



I admit, I am not also encoding Dollhouse. I've just been using the same settings for a long time and I determined my subjective experience of the videos with the bitrates they had beyond what I could achieve. It's eye opening that the encode settings seem so pedestrian.

Ugh, on further inspection, I do see they kind of "cheated". Filtered to be able to compress better -- I had no idea this was a thing. I see now in some release notes, "The SSIM measures the accuracy of the outputted encode verse the source. It does not reflect on the sharpness or awesomeness of the image, only how close it is to the source material. An "S##" is a score where filters where [sic] not used. "FS##" is an encode where we used filters before the encoder, usually for nasty amounts of grain, this can throw off the score usually in a positive way and we like to be clear and honest [...]". Huh. Looks like the encode settings I copied into this thread were from an episode that had been pre-filtered.



Better in this case is subjective, and drawn on all of my past experiences with the encodes I've done. It seemed to me that more detail was retained at a lower bitrate than I've ever managed. The episode[s] looked superior to what I've been able to achieve at that bitrate. What can I say? I give up easily.

I have no idea how this pre-filtering for better compression works, but I'd rather just stick to encoding settings, if I can get Handbrake to utilize the CPU effectively. If pre-filtering has real merit, then I imagine it'll eventually become a part of mainstream encoding software.

Oh, this is more than one. Psy-rd and Psy-rdoq. That makes experimentation more difficult. I would ask though, do you prefer to use one of these or both? If just one, which one? Or is there a case that merits one over the other, or both?
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Old 31st July 2019, 17:54   #18  |  Link
Ischemia24
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So I have made a few changes to my baseline settings and I feel as though the quality retained at the restrained bitrates I'm using has really leveled up! Thank you Excellentswordfight for the suggestion of using no-sao and deblock -1:-1.

I came across a post claiming that H.264 changes to these settings when tuning for Film (which is what I need most of the time)

deblock=-1:-1
psy-rd=1.0:0.15

So now my default settings look like this.
rc-lookahead=120:bframes=12:ref=6:subme=7:deblock=-1:-1: psy-rd=1.0:0.15:no-sao

I should do some additional testing to find out how I feel about the subjective quality of CRF at values that result in similar bitrates to what I am specifying. I recently had a problematic 480p encode that ended up looking great just changing to CRF 22 (the video bitrate went up ~40% though).

I looked into VMAF and while I appreciate that it exists I decided I would rather subjectively evaluate my encodes.

Are there any other settings I should consider applying to improve the quality to file size ratio? I understand that some settings could be adjusted for better encoding performance in different situations with no noticeable quality loss, and feel free to chime in about that if you'd like, but I would like to get the highest quality to size ratio possible within the scope of the H.265 settings.

How would you approach dealing with a particularly grainy source?

Any thoughts on the usage of the frame-threads setting? A higher number seems like it would increase CPU utilization, but my understanding is that it would go against my goals (and that if I want to be even more ridiculous, I should use frame-threads=1), so I decided I should leave it at the default.
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Old 31st July 2019, 20:19   #19  |  Link
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In a recent enough build, there's the new option --hme which is meant to improve motion estimation.

Personally I've also raised qcomp from 0.6 to 0.7 and set rd=6 and use --rd-refine.
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Old 31st July 2019, 20:20   #20  |  Link
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First let me say, that I used to have a similar goal as you. I used to say the most quality per bit... I'd have encodes that took several days even on a 16c Xeon v4. Then I changed and figured a couple hundred megs more per file wasn't worth days of encoding.

But anyways...

Increase your --bframes to 16 which is the max HEVC supports while saying in spec. You can also use --bframe-bias to increase the likely hood the encoder will use a b frame. I'd say a sane range would be 0-10 for bframe-bias.

You might find --me sea or full will give a bit better compression and quality but with an increase in encoding time.

If you should consider dropping --subme 7 to 5. You'll find --me sea is more likely to provide better quality and possibly a smaller file size.


There is a relatively new setting for motion search --hme. It changes how MS is done. It is supposed to be better quality while being less computational intensive. I've found the settings below are about 7-9% slower while producing a file 1.5% smaller with about the quality as --me 3 --subme 5.

--hme --hme-search 1,2,3

This was about 2.2% smaller but a 43% longer encoding time. I found it noticeably better quality - subjectively of course.

--hme --hme-search 1,3,3



I would suggest trying lower values for --rc-lookahead 120, it is very high. I'm not sure your getting substantially better frame placement vs it set to 60. It'll improve your coding time with negligible difference in size.


You could also set --tu-inter 4 and --tu-intra 4. Those will allow the encoder to look for better compression opportunities.

FYI, I doubt handbrake will support the new HME settings. This was recently made available. You could try something like ripbot264 and download the latest x265 build from the HEVC thread on Doom9.

Good luck.
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