CRF Values

[Anakin]

Just wondering what CRF value everyone uses and for what resolution? H264 and H265?

[butterw]

the default crf=23 is typical for compressed hd x264 video. 21-25 is commonly used.

[jagabo]

It varies depending on the purpose of the encoding. I usually use CRF 18 in x264 for video that I'm going to watch (I keep my collection on a NAS, accessible from any PC/TV in the house). Sometimes a little higher for stuff I don't care that much about, a little lower for videos where visual quailty really matters.

[Hoser Rob]

I ddon;t think you'll find total consensus here. But I would say that for example you'll need a lower crf for Lord Of The Rings than old anime. It depends on the source a lot.

[Anakin]

I ddon;t think you'll find total consensus here. But I would say that for example you'll need a lower crf for Lord Of The Rings than old anime. It depends on the source a lot.

I am just interested in what people say. The more opinions, the better.

[zing269]

I also use 18 for most stuff. 20 is as high as I'll go as I find the lack of quality distracting at higher CRFs.

[Bubb]

For examlpe like VHS :

1920 x 1080 res : crf=20 high quality, crf=25 normal, crf=30 long play (here x265 better quality, x264 blocking)

But CRF can also be thought of as an image quality balance that can be shifted back and forth.

[_Al_]

Movies? Waste of time anyway. If you insist to encode something you like, then be generous, quality is preferred over quantity. And movies are in vast range of shape. A guy would show up saying, "I prefer quantity over quality". Other would say "I prefer Quantity and quality at the same time". So there is no answer for what you ask.

If those are unique videos of yours, which means you prefer quality and considering how it was obtained, VHS, DVavi or HD coming from a camcorder, you need lower CRF for those lower resolutions to not introduce more artifacts. For SD resolution I'd still use x264 (H264) over HEVC even if progressive.

[Alkl]

For animation I use the following

• x265 - crf 17 / 18
• aomenc - q* 25 / 30

* (the quantization setting in aomenc seems to act like a constant rate factor, I can be wrong tho)

For live action:

• x265 - crf 20-25
• aomenc - q 28 / 35

In the end it really depends on the source. There are cases were x265 crf 18 is completely overkill for animation, the same goes the other way around.

Keep in mind, that CRF is not a constant quality, it will adjust the quantizer accordingly to the scene complexity / motion.

[hello_hello]

I ddon;t think you'll find total consensus here. But I would say that for example you'll need a lower crf for Lord Of The Rings than old anime. It depends on the source a lot.

Sometimes old anime can be hard to encode well, because large blocks of color and/or color gradients can result in color banding. There's ways to discourage that sort of thing, but more accurate encoding almost always requires more bits, which you get from lower CRF values.

When there's detail everywhere there's less likely to be banding problems, but of course live action and CGI etc can challenge an encoder in different ways. Live action will probably result in a higher bitrate than anime at the same CRF value, all else being equal, but mightn't need a lower CRF value. Or it might. Or maybe not......

[sophisticles]

My views are well known, I do not use crf and refuse to use it for anything other than testing,

[hello_hello]

My views are well known, I do not use crf and refuse to use it for anything other than testing,

Yeah... but it's pretty odd given every time you use it for testing you seem to prove how well it works.