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TMPGEnc Video Mastering Works 5 BBS [ Sorted by thread creation date ]
I am trying to understand how to output using the popular CRF method. MW does not use this. It seems "VBR constant quality" is the same thing, as suggested by an older thread: http://bbs.pegasys-inc.com/bbs/list/lang/en/board/TVMW5/keyword/crf/topic/64203#topic64203
However: the 0-100 quality setting seems to have absolutely no effect on the output's file size. Tried higher and lower settings. Then, there is the strange "maximum bitrate" setting, which doesn't make sense for CRF use, which is supposed to define on its own the needed bitrate, solely based on the quality setting.
I'm not sure what's going on, and wish Pegasys used the well-documented 0-51 CRF output numbers.
hi, yes i agree with you, CRF or RF as i know it can be beneficial, however how do you know which RF quality factor to set for any given input file.
the free handbrake and Xmedia Recode programs are wonderful conversion tools, and both use an RF quality factor mode for setting your output quality, or you can use the Bitrate method, but oddly both those programs use a totally different method to calculate the RF bitrate, so if you encode the same file using the exact same settings, including the same RF quality factor, one will output the file at a much higher bitrate than the other, so this is where you must be very careful using the RF method, you need to know and understand how your given software sets this formula.
i just started using TMPGEnc but only for converting 1080/50p m2ts files from my camera to dvd compliant mpeg2 format so i use a constant bitrate setting of 8.0Mbps.
my regular preferred software is Video ReDo and that has built in quality presets that does the work for you based on pre-determined output quality settings, and thats the way it should be done, not have to guess what bitrate your output file is going to have.
The 0-100 quality setting is a feature that was first introduced in previous (ie. no longer available) TMPGENC products. The value has nothing to do with CRF values. In fact, I only found out about 0-100 from forum posts dated about 2004 when people were still making SVCDs. From what I could make out, 100 is the best, 0 is the worst and 50 is the default. In those days people would try values above 75 but they might end up with bigger than expected files. You just have to try a value and see if you can live with the file size. In the end I just gave up and went back to setting 2-Pass VBR with a bitrate setting ... or I use another tool that accepts CRF
Since the new AVC encoder is supposedly based on x264, anyone know how the CQ control relates to x264 ones? When using x264 I prefer to set CRF between 18 to 22. How do I do something like this here? Also can't seem to find any settings for the quantizer. Seems to offer less control than v4. I'm kind of underwhelmed so far.
The x264 in TMV5 actually uses the crf factor when set in Constant Quality (CQ) mode. The relation from the 0-100% quality scale to CRF is : CRF = 1 + (100 - Q)/2
So in your case, if you want CRF between 18 and 22 you would use Qualities between 66 (CRF=18) to 58 (CRF=22).
You can always check the actual CRF value used by the x264 encoder with the MediaInfo utility.
For the advanced x264 parameters, hit the "MPEG Output" button.
i tried but couldn't work it out ( not the best with maths ) could you please tell me the numbers for the following CRF values for x264 in tmpgenc mastering works :