What bitrate do you recommend for 720p and 1080p mp4 films?
I use 3000 kb/s for 720p and 6000 kb/s for 1080p. Are these good values to use?
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There's no right answer to this question. Most folks use quality based variable bitrate these days instead of constant bitrate because some scenes -- high action require more bitrate than others -- talking heads.
Do some tests though, and see what you find acceptable.
I forgot to mention that it is VBR and 2pass that I mostly use.
Yes I've heard about the Constant Quality thing, with a number instead (18 - 25). I will give it a test and compare a little.
Does anyone know what value of CQ which correspond to 3000 kb/s (720p) ?
Last edited by brusno; 21st Feb 2013 at 17:17.
The x264 encoder encodes the same way for both 2 pass and CRF encoding, assuming the final file size is the same. ie if you run a CRF encode, then use the resulting bitrate/file size for a 2 pass encode, the 2 encodes will be virtually identical.
The difference is one method lets you specify the file size without knowing what the quality will be, for the other method it's the other way around. CRF 18 is generally considered to be "transparent" and is probably about as low as most people go. The higher the CRF value the lower the quality and smaller the file size, but between 18 and 22 should look pretty good.
I asked the same question some time ago about the standart comrpession values and they told me the same - there is no common value...
Put it this way. It's sort of analagous to what you see in automated factories. You have lower skilled people working on the production line. They just plug in the numbers they're told to.
This is what people who are new to encoding want.
And in those factories you have highly skilled technologists. They have to actually understand how all the machines work, set them up, and use their judgment to make adjustments.
That is how encoding settings actually works. It can't be simplified to the degree noobs want.
Quality based encoding is pretty much as good as 2 pass from what I've tried and much faster. The real reason I started using it was I was beginning to use more advanced h.264 encoder settings. You get a huge difference in quality. But you can barely scratch the surface and encoding will take 3X as long. Even with a gaming box that'd be unacceptable to me.