Sizing the output file with CCE SP 2.70

[Dr.Khron]

Can you rely on the estimated file size that CCE shows?

I'm trying to encode some files for a DVD, so I have an exact size target for each file. I wanted the first file to be 814,000 KB, which is about 99.3% of the space alloted for that title's video.

I ran the encoder in VBR mode, and I set the size to 814,000, which adjusted the Average bitrate to 2,475. I set the minimum to 1,800 and the max to 5,000.

The file that CCE produced was 829,817 KB in size. Too big!

is this normal fluctuation of file size, or is there a better way to calcluate the bitrate to acchieve a desired size?

I pushed some numbers around a spreadsheet, and decided that an average rates of 2,430 might to better to hit my target size. However, at this bitrate, CCE estimates the final file size at 799,884.

Suggestions welcome.

[Susana]

In bitrate terms, k=1000, whereas in drive, k=1,024. Maybe that's the difference, but there are always fluctuations.

814*1,024=833 ?

[Dr.Khron]

Yah, I figured it was something to do with that...

How much does CCE typically vary from its target?

[Susana]

I have no idea, sorry

[Boulder]

How many passes did you do? If you use the adaptive quant matrix feature and do only 2 passes (the vaf file creation + one pass), CCE often does not hit the target. It takes the third or even fourth pass to do that depending on the material.

[manono]

And if you're filling in a size, and not a bitrate, you want the KiB or the MiB.