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DivX265 doesn't have those so I figured I'd keep it as even as possible. I can re-run the test tomorrow though.
P.S.
Your fix not only seems to have taken care of my regular AviSynth 2.6a folder but now hybrid's AviSynth functions wotk for me, without having to touch hybrid's folder. Might just be a coincidence -
Why would I be upset? LOL . I just make observations. I'm just interested in the truth
The truth is (at least with x264, I haven't used x265 enough to see if this holds true for x265) - Typically you get higher values by tuning SSIM and PSNR, occasionally this isn't the case, but try it out yourself . Obviously you know I've done a gazillion tests, trust me on this
These metrics are of limited value anyway. Take actual look at the image quality
And there is that "by up to xxx%" claim again. I'd take those marketing words with a grain of salt
Why are you so emotional ? -
DivX265 doesn't, but their encoder, like all Mainconcept varieties are generally tuned for PSNR at default. Their engineers optimize for this, just like many other codec developers. You can tell by the encodes in the other threads, the hallmark is smoothing and lack of detail, esp. in shadow areas. Things like psy, AQ typically reduce SSIM and PSNR values, but subjectively they do make image look better (not always, but most of time). Actually if you turn down AQ, psy, x264 begins to look a lot like Mainconcept encodes
Objective metrics have their place, but they are only limited in value. I won't discuss it here because pros/cons are discussed extensively elsewhere
Tests are usually designed run with an "endpoint" in mind. So if the endpoint is SSIM, you usually encode for SSIM . You don't handicap an encoder just to level the playing field, you show the encoder in the best possible light -
The only true test of quality are your own eyes and taste. One man's trash is another man's riches.
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for the love of Gandhi! main concept's h264 has AQ and in fact they have 3 or 4 different settings, but only some apps expose them all. also the divx hevc encoder does have AQ, that's what the presets refer to, which may explain why SSIM was lower for the slower settings than the faster with divx.
by the way, despite the fact that DS spent 10+ years discrediting mathematical measurements like SSIM and PSNR, the fact remains he has admitted that they are an accurate method of testing changes within an encoder, i.e. measuring the impact of certain settings and he has used it when convenient to promote his half-assed encoder.
more importantly, the MSU comparisons that his supporters always point to as proof that x264 is the best encoder all use math metrics as their method of determining a winner, look at their reports it's full of average and peak SSIM and PSNR readings. -
Yes, but they don't work very well. I wrote about this many years ago, posted comparisons - I think you particpated in that thread.
by the way, despite the fact that DS spent 10+ years discrediting mathematical measurements like SSIM and PSNR, the fact remains he has admitted that they are an accurate method of testing changes within an encoder, i.e. measuring the impact of certain settings and he has used it when convenient to promote his half-assed encoder.
more importantly, the MSU comparisons that his supporters always point to as proof that x264 is the best encoder all use math metrics as their method of determining a winner, look at their reports it's full of average and peak SSIM and PSNR readings.
Yeah, so he picks one outlier that happens to be x% and that makes the statement logically true . Marketing 101 -
Hi @ Jagabo
Though PSNR values might not give impression on quality, the range of PSNR itself tells on the probable quality of video output. If not PSNR what are the metric used to compare. What are the BD rate gains in case of DiVXh265 as compared to HM. hence the suggestion was to have some comparison metric. -
@deadrats: LOL, playing the stupid brat again and getting all folks rattled *congratulation*
It's sad that the thread get's derailed with all the name calling and bs,.. -
There's one in every forum, and here it's deadrats.
After claiming in the other thread the Divx h264/5 encoders don't have a deblocking filter, I'd have hoped he'd refrain from posting in any of the h264/265 threads for a little while.... till most of us have forgotten he doesn't know what he's talking about, but apparently not......
You'd expect a grown-up to return to at least post "I was wrong", but for reasons I don't understand being an adult is hard for some, even behind the anonymity of a username and the internet. -
ssim and psnr results
CRF 18 preset mediumLast edited by gonca; 8th Jul 2014 at 19:30.
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A metric is a mathematical algorithm which will never accurately measure subjective impressions of all people. No machine can measure if "it looks better". So please, stop overestimating the meaning of PSNR, SSIM, and whatever metric will be developed in the future. Quality is a fuzzy term, and even the meaning of an ABX test of thousands of probands is limited.
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I don't mind you running tests and reporting values.
I am just afraid of generalizations like "this number is smaller, therefore that quality is better". That may often be true if the difference is remarkable (debating about permille differences is meaningless). But there are academic samples how to fool metrics (e.g. PSNR is not as sensitive as human perception to impulsive "Salt & Pepper" noise, but very sensitive to already slight contrast changes or blur).
A better metric value only means "a better metric value", but not certainly "better quality preservation for the average human recognition". -
I'm only running the tests because I was asked to, and I offer no opinions on the results.
Personally, I believe that the only metric that counts is the one that uses your eyesight and viewing equipment. -
That would probably be an ABX test with as many participants as possible. Like Roberto Amorim once did for audio formats, with support by the HydrogenAudio forum users.
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Not only do you know I'm on parole but you know the exact crime I've done that restricts use of PCs upon release. It must be awesome to know everything about everyone.
EDIT: About the debate about usefulness of SSIM. It is accurate to compare large disparities of scores but not small ones. An SSIM score of 0.99050 vs 0.99100 doesn't prove shít. But a 0.98500 vs 0.99000 shows a clear difference that a majority of the time is a lot better quality.
In the million SSIM tests I've done and tests I've seen others do, I am yet to see an example of a video getting an extremely lower SSIM score yet being better quality.
Yes, I've seen scores as low as 0.89000 where the quality wasn't so bad and ones as high as 0.98500 that looked like garbage but never a large disparity of the same video without the quality perfectly correlating to it.
Consistency is the key and not comparing apples and oranges with an "objective" metric and expecting accuracy.
x265, x264, Xvid, MPEG-2 are all refined versions of the same DCT algorithm so they are easy to compare with the same metric accurately.
Try comparing wavelet and DCT at the same bitrate like JPEG and JPEG 2000. It'll be hard to tell which ones are better even when using your eyes. In many cases the wavelet photo won't look necessarily better, just different. You try to decide which artifacts are more annoying and which details are more important to retain. It's a mindfück.Last edited by Mephesto; 12th Jul 2014 at 11:37.