Standard Definition High Definition Constant Quality Setting

General questions or discussion about HandBrake, Video and/or audio transcoding, trends etc.
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sorin86
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Standard Definition High Definition Constant Quality Setting

Post by sorin86 » Thu Sep 18, 2014 8:06 am

The help balloon for Constat Quality settings says:

"Lower values correspond to higher quality"
"Suggested values are: 18 to 20 for Standard Definition and 20 to 23 for High Definition"


Isn't there a contradiction? HD means better quality than SD, so the recommendation should be oppositely, right?

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JohnAStebbins
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Re: Standard Definition High Definition Constant Quality Set

Post by JohnAStebbins » Thu Sep 18, 2014 1:28 pm

No. When you are starting with a higher quality source, you can sacrifice a little quality during transcoding. Quality loss is a compounding effect, so loss of quality when transcoding a low quality source is magnified.

musicvid
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Re: Standard Definition High Definition Constant Quality Set

Post by musicvid » Thu Sep 18, 2014 1:44 pm

If you compare the number of pixels in a bluray frame to a dvd, for example, the order of magnitude is something like 7:1.
It simply leaves more room for compromise.

mduell
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Re: Standard Definition High Definition Constant Quality Set

Post by mduell » Thu Sep 18, 2014 4:15 pm

CRF is more like quality per pixel than total quality, so you can go lower quality when you have more pixels.

musicvid
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Re: Standard Definition High Definition Constant Quality Set

Post by musicvid » Thu Sep 18, 2014 5:39 pm

For those interested in more in-depth information, search "bits per pixel" and
The Ben Waggoner ^.75 Rule

The Handbrake suggestions you quoted in your first post are pretty close to that "rule," depending on your source of course.

sorin86
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Re: Standard Definition High Definition Constant Quality Set

Post by sorin86 » Tue Sep 23, 2014 8:58 am

Some replies, but no so clear.
This is what I got:

That CONSTANT QUALITY slider shows how much quality you lose during conversion.
If it is 50, you lose a lot of quality (practically, you get an unusable video).
If it is 0, you lose no quality, but the final video gets much larger.

If the source is Standard Definition, to get a nice quality PC video (whatever that means!), you can set the slider to 18-20.
If the source is High Definition, you can afford to lose more of the initial quality (which is greater) to get a final similar "nice quality PC video". Thus you can use a setting of 20-23.
If you have 25 dollars, you can consume 19 dollars on food and then you'll have money for some drink.
If you have 28 dollars, you can consume 22 dollars on food and still have the same money left for the same drink.


That should be more clearly explained on that help balloon.

musicvid
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Re: Standard Definition High Definition Constant Quality Set

Post by musicvid » Tue Sep 23, 2014 10:22 am

The replies you got, along with the tooltip itself, are clear.
How much information did you want to see in a tooltip?
No matter how much explanation is given, some people simply do not accept it.

Smithcraft
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Re: Standard Definition High Definition Constant Quality Set

Post by Smithcraft » Wed Sep 24, 2014 11:55 am

People keep asking the same question. I doubt that putting different expressions in the tool tip would help in any way.

SC

sorin86
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Re: Standard Definition High Definition Constant Quality Set

Post by sorin86 » Thu Sep 25, 2014 8:51 am

The explanation on the Help balloon is unclear, that is exactly why people will keep asking.
Where are those days where the Help environments were designed by smart analysts? :)
Today not even Google is capable of coherent Help.

musicvid
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Re: Standard Definition High Definition Constant Quality Set

Post by musicvid » Thu Sep 25, 2014 12:05 pm

You are welcome to post your suggestion in the Feature Requests section; complainers generally don't last very long here.

Smithcraft
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Re: Standard Definition High Definition Constant Quality Set

Post by Smithcraft » Fri Sep 26, 2014 11:20 pm

One problem is that people refuse to believe what the tooltips indicate. It's not an error, that's the way CRF works.

Just like when people want to know what the best preset is for their device, ie AppleTV, when there is an AppleTV preset that they don't think is the one they want to use.

SC

sorin86
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Re: Standard Definition High Definition Constant Quality Setting

Post by sorin86 » Wed Mar 11, 2015 10:41 am

Glad it was redesigned! :)

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