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datascab
26th December 2003, 08:55
Hello and Merry Christmas :)

I've recently finished an encode of Matrix 2.

I chose 2-pass vbr, normal motion, very high EHQ and a final file size which with audio equated to a bits/pixel = 0.193 (bitrate approx 1460kb/sec), all this at a anamorphic 716x424 (1040 x 424 rs).

Since AutoRV9 has the problem displaying the corrects bits/pixel with anamorphic options are ticked I make sure of the quality setting in 1:1 mode then enable anamorphic afterwards.

Here is the properties sheet for the *.rmvb file: -

http://homepage.ntlworld.com/skivy/matrix.txt

The thing that confuses me is this. The overall bitrate for the movie is around the target bitrate. However this seems to be the sum of the video and audio bitrates.

Therefore if i calcualte the bits/pixel based on the video stream alone then i get a bits/pixel as follow: -

bits/pixel = 1197185/(25*716*424) = 0.157

However if I use the summed bitrate it works out to be: -

bits/pixel = 1465230/(25*716*424) = 0.193

So does this mean that AutoRV9's calc for bits/pixel is inaccurate since it seems to be calculating the quality setting on the full file size and ignoring the fact that the audio needs disk space (in this case over 200mb).

Also does this mean if I want a really good encode i need to increase the final file size to get a bits/pixel in the order of 0.190 and also do a calculation of my own to determine this?

Sorry if this is a previously discovered bug or if i've missed some other detail.

Thanks

Data

Dark-Cracker
26th December 2003, 15:54
hi,

hum yes u are right i have working to improve the bits/pixel function and i have found this bug a few days ago, of course it have been fixed.

thank u for pointing me this problem :)

Bye. and happy new year :)
++

datascab
26th December 2003, 19:04
Thanks,

I look forward to future revisions.

Merry Christmas and a Happy New Year!

Data