I am somewhat new to using handbrake as I have been mainly ripping dvds to the VIDEO_TS folder structure and recently migrated to MakeMKV. I have an issue where I need to convert my VIDEO_TS rips to something else and figured mkv was as good a choice as any and started to use Handbrake to do it. I am not terribly worried about space, so I just wanted to keep the original source quality. I will fully admit I am mostly a novice at the whole HTPC arena and so I went into the video quality section of handbrake and turned the Constant Quality slider to "0" and let it run. My output was about 3 times the size of my input. So can anyone give me a good idea on what the setting should be and maybe some reasoning behind what it actually does. I would have thought (incorrectly) that "0" would have simply kept the source quality but apparently that isn't exactly the case.
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Handbrake configurations
- Thread starter bbenz33
- Start date
Basically what CRF does is dynamically adjust the bitrate to maintain the quality within a certain range. It's more complex than that, but that's what the Handbrake and x264 docs are for.
You do want to use Constant Rate Factor. A CRF of 20 will produce a nearly imperceptible reduction in quality, although many people prefer CRF 18 or 16 for Blu-Ray (but they come with a significant increase in size) and CRF 22 for DVD (I guess with the idea that if it's going to be slightly blurry anyway, a slightly larger quality loss is less likely to be noticed). I can tell you that I cannot tell the difference between a Blu-Ray transcoded at CRF 20 and the original on my 40" LCD at about 2m (7') away.
Most of the settings in Handbrake have tooltips. For example, if you mouse over the Constant Quality radio button it gives a decent explanation and in fact explicitly addresses a CRF of 0 - that's lossless compression i.e. it will be pixel-for-pixel identical to the original source using only lossless compression techniques.
There are many settings in the Advanced Settings page that you should use. Mouse over each to get an idea of what they do.
You do want to use Constant Rate Factor. A CRF of 20 will produce a nearly imperceptible reduction in quality, although many people prefer CRF 18 or 16 for Blu-Ray (but they come with a significant increase in size) and CRF 22 for DVD (I guess with the idea that if it's going to be slightly blurry anyway, a slightly larger quality loss is less likely to be noticed). I can tell you that I cannot tell the difference between a Blu-Ray transcoded at CRF 20 and the original on my 40" LCD at about 2m (7') away.
Most of the settings in Handbrake have tooltips. For example, if you mouse over the Constant Quality radio button it gives a decent explanation and in fact explicitly addresses a CRF of 0 - that's lossless compression i.e. it will be pixel-for-pixel identical to the original source using only lossless compression techniques.
There are many settings in the Advanced Settings page that you should use. Mouse over each to get an idea of what they do.
Thanks for the reply. Yeah I did read the explanation for CRF, but didn't understand it. I was under the impression that CRF 0 would be a 1:1 of the original and therefore the same size as the original. I don't think I found the advanced settings yet so I will continue to look around.
You do want to use Constant Rate Factor. A CRF of 20 will produce a nearly imperceptible reduction in quality, although many people prefer CRF 18 or 16 for Blu-Ray (but they come with a significant increase in size) and CRF 22 for DVD (I guess with the idea that if it's going to be slightly blurry anyway, a slightly larger quality loss is less likely to be noticed). I can tell you that I cannot tell the difference between a Blu-Ray transcoded at CRF 20 and the original on my 40" LCD at about 2m (7') away.
Your experience is much different than mine with CQRF. A value of 20 on Blu-ray will product files with very noticeable blocking on the image. I usually have to go to a value of 25 to get results that look very good on any of my screens. Perhaps there are other setting that impact this, but I find if I go less than 25 I'm getting results that are very enjoyable to look at.
Your experience is much different than mine with CQRF. A value of 20 on Blu-ray will product files with very noticeable blocking on the image. I usually have to go to a value of 25 to get results that look very good on any of my screens. Perhaps there are other setting that impact this, but I find if I go less than 25 I'm getting results that are very enjoyable to look at.
I think you might be a little confused. With CRF a lower value is higher quality. A CRF of 25 would produce very noticeable blocking on most source material.
What version of Handbrake are you using? When mb-tree was introduced it changed the effective meanings of the CRF values - if you're still using 0.9.4 then the values I'm talking about can't be compared.
I looked at the presets briefly, but didn't see one that I thought was applicable, so I figured I needed to create my own.
For most purposes, just use the High Profile preset - or start with it and begin experimenting.
Thanks for the reply. Yeah I did read the explanation for CRF, but didn't understand it. I was under the impression that CRF 0 would be a 1:1 of the original and therefore the same size as the original. I don't think I found the advanced settings yet so I will continue to look around.
Advanced settings is four tabs over from the Video tab (at least on Windows).
CRF 0 is a 1:1 of the your source. However, what you're missing is that Handbrake (well, really x264 because that's what Handbrake uses) always re-encodes the video. In order to achieve a pixel-perfect duplicate of your source while re-encoding, it cannot use any of the lossy compression methods.
Remember that your source is a copy of the original source, and your source has already undergone lossy compression. But Handbrake isn't operating on that original source. With CRF 0 it needs to produce a pixel-perfect duplicate of what you've given it. And if it uses lossy compression methods, by definition it will be unable to do that.
If you really want no reduction in quality, then you shouldn't be using Handbrake. Instead I suggest just using MakeMKV to extract the main title to mkv.
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I would prefer to use MakeMKV but unfortunately the files were ripped to VOBs and were ripped to only include the main title so MakeMKV errors when trying to read the files. I will probably mess around with the CRF setting tonight and then when I get one that I like simply batch process them all. Thanks for the informative answers.
I think you might be a little confused. With CRF a lower value is higher quality. A CRF of 25 would produce very noticeable blocking on most source material.
What version of Handbrake are you using? When mb-tree was introduced it changed the effective meanings of the CRF values - if you're still using 0.9.4 then the values I'm talking about can't be compared.
You're right....I was using 0.9.4 but got the later version not too long ago. Not sure how I got this totally backwards...but I'd still swear that the blu-rays done at 25 look better than the ones done at 20...will have to recheck all this now.