Odd Numbered Video Data Rates

[ptfigg]

You can drag a QT Movie into the Custom Presets Folder in Apple Compressor. Compressor will then analyze the encoding attributes, and you can save out the results as a new Preset. I tried this with a few 1080p movie trailers. I noticed a trend with the video data rates.

What is the significance of odd numbered Data rates? For example 6976 kbits/sec? This setting was keyed in by the person who encoded the movie. Why not set that to 7000, or any even number for that matter?

As a side note - using aspect ratio conversions as an example - I realize and understand why many purists prefer to resize video using multiples of 8 or 16. Is there some sort of similar relative concept when selecting data rates?

Thanks.

-paul.

[aedipuss]

vbr.

size as a multiple of 8 is usually an encoder requirement.

not so for bitrate.