[XviD-devel] Slow encoding - pondering the cause

[Radek Czyz]

Hi :)

J. Grant wrote:

> Is there an optimal resolution for encoding a video at bitrate 1000 ? 
> For instance I could encode at 640x480 or at 1024x768, the former would 
> have more quality in the fewer pixels and the latter would have less 
> quality in more pixels.  Which is more suitable?  Perhaps there is a 
> comparison graph?

As Christoph said, doom9.org is the best place to get encoding tips and 
answers.

As for your question, people have invented a term "compressability" as 
their rule of thumb. It's a ratio of first pass' encode (or just fixed 
quant 2 encode) to your desired size. For xvid, it is usually 
recommended to have this ratio at about 60..75%, although I personally 
always prefer higher resolutions (all the way down to 40% is often 
better in my eyes).

Please just don't make the mistake many people make - if different 
encoder's settings give you better "compressability" then they do *not* 
have to be better. Use "compressablity" as your rule of thumb for 
resolution, and possibly for filters (up to a degree) but not for 
encoder's settings.

Radek