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stuck19
07-17-2007, 10:25 PM
Hi,
I've tried encoding a few files with mpeg-4 codec at a high bitrates like 2500. My resulting files however, don't seem to be actual encoded at this rate, but much less like 1200 kbps according to videora. Is there some sort of software or method I can use to calculate the actual bit rate of my encoded file? Does anyone know of a way I could encode a file say at a constant bit rate of 2500 kbps? I've tried SUPER, but the results have been similar.
Any explanation at all on what's going on I'd really appreciate.
Thanks

Midiman
07-17-2007, 10:27 PM
Try Gspot for analyzing your file's bit rate.

http://www.gpsot.com

stuck19
07-17-2007, 11:17 PM
Oh well, so it seems that when changed the setting under "advanced 1" so that the minimum and maximum bitrates were 2500, the video was actually encoded at this bitrate, according to gspot. It's still strange though because it's file size is almost the same as another version of the same video with the settings under "advanced 1" set to 0 and 768 (default). Any idea how this could be?

In any case using the H.264 codec to encode these files seems to work much more accurately.

Thanks again for the help.

Midiman
07-17-2007, 11:26 PM
Both the mpeg-4 formats supported by ViC have different maximum bandwidths for different resolutions.

stuck19
07-18-2007, 12:21 AM
I think I understand, but please bear with me. I have another question, and I don't think I was clear above.

I had two files set to be encoded at 2500kbps. On one, I set the maximum and minumum bitrate both to 2500. This file shows up on gspot as having a video bitrate of 2500. The other, which had the same setting except for the max/min bitrate, is of the same size as the first, but the bitrate according to gspot is ~1200 kbps.

So is there nothing wrong with this? I find it hard to believe that the file with the higher bitrate doesn't have a substantially larger file size.

Again, I really appreciate the help.

Sketch
07-18-2007, 05:37 AM
I find it hard to believe that the file with the higher bitrate doesn't have a substantially larger file size.
Are the original videos the same length? Remember, size = time * bitrate.

stuck19
07-18-2007, 07:28 PM
Yeah, they're both about 22 minutes long.

Sketch
07-19-2007, 04:39 AM
Could we see console logs of both conversions please?