Simple CQMatic Questions
 

Happy New Year everybody!

Thanks to all you good folks on this forum, I have used ToK successfully to do some encodings. However, while keeping an eye on the discussions in the ToK forum I read from Dialhot that CQMatic gives better results, so I read further on CQMatic and did a trial encoding yesterday. It was unsuccessful, but after reading here some more I think I can correct the mistakes I made earlier and I ready to try again. Before I do, I have a few simple questions:

1. The time of the movie in minutes: if the movie is say 120 minutes and 37 seconds, should the seconds be converted to 0.62 minutes, so that the time entered in CQMatic is 120.62?

2. On my movie, MovieStacker gives the average bitrate as 752 (scene change detect enabled), but CalcuMatic gives the average bitrate as 781. Which is the more accurate figure to feed to CQMatic?

3. The CQ settings in TMPGEnc ask for Max and Min bitrates, but the scroll up/down buttons only move in jumps. Should we type in directly the max min values given by MovieStacker, or can we scroll to the nearest values?

Thanks for the education.

Re: Simple CQMatic Questions
 

The tool ask you minutes, so enter minutes and don't bother with seconds. 120 is far enought precision here.

Forget what moviestacker says.

Type in directly.

Thanks, Phil.

Final question: I read on one of the threads that the min bitrate (entered into TMPGEnc) should be 0.57 times the average bitrate, and is supplied by CalcuMatic. Is this accurate? Thanks.

It's only a recommandation for a better accuracy of cqmatic. I do not use it myself and can live with some (rare) failures of the tool.

If you use X3 (long) prediction in CQMatic, you can use any MIN bitrate you want.
:arrow: Use the lowest that your standalone can handle.

-kwag

Karl,

Forgive my ignorance, but what is the difference between X1 and X3 prediction? Is it related to the length of the movie, or to the TMPG template?

X3 mode takes three times longer to predict, because it takes three times more sampling of the footage :)

-kwag

If it takes three times longer to predict using X3 mode than X1, why would anyone use X3 instead of X1?

Because it much more accurate !

Exactly :!: :D

Thanks. I think I am going to try the X3 mode for my future encodes.

Just use X3 mode just before going to bed. In the morning, you should have a pretty good accurate encoded mpeg file.
I said, "you should", but not necesarily: "you will" :mrgreen:

-kwag