X264 minimum file size

[Jemm54]

Hello guys,

I got a question about the file size in the x264 compression, i use Megui, and allways set the file size like 50 o 60mb in 848x480, and 80 or 90mb in 720p, with good results, but exist any way to define the minimum file size, without compromising quality too, I want the codec decide what is best for my video, or somethin like that...

thanks (sorry for my bad english XP)

[mirkosp]

Use the Constant Rate Factor (CRF), also known as Constant Quality.

[Jemm54]

Im not sure, but is that??




I never knew what it was this field, goes from 0 to 100, what i have to put here?, i guess if its like xvid 0 is the best quality and 100 the worst, no?

[mirkosp]

I don't know how megui does things, so... I'm not sure if it's that or not. That might just be the more generic quantizer.

[Jemm54]

I'm not sure if it's that or not. That might just be the more generic quantizer.

Oh, ok, i wil search "Constant Rate Factor" in the megui forum, thanks for the hint... I knew there must be some way to do...

[Mister Hatt]

MeGUI is dead, stop using it. There is a superior basic GUI that Zarxrax knocked up, should be around here somewhere. Or just use x264 itself. No idea why people keep thinking x264 is a format, it's an actual encoder that all the GUI's wrap around.

There is no way to define the 'minimum' file size, but a constant ratefactor will always give you the smallest size you need to fit a specific visual quality level. The numbers don't mean anything in particular though, they change depending on options and resolution, for the same quality.