Encoding

[OG24]

Hi,

I was wondering y do some encoders encode files WAY quicker than others?
Even if they have the same options, y would one encode faster than the other?

[redwudz]

Which encoders? If you were asking about the codec that does the encoding, such as Xvid or Divx, the speed would be exactly the same using the same settings and same codec, irregardless of which encoder type program is using it.

If you are getting different speeds with two encoding programs that are using the same codec, then the settings aren't the same.

The codec itself is what does the work of encoding. The programs that use the codec are just 'front ends' for it. And they may be making all kinds of settings adjustments. Adding filters, resizing, changing the audio format or many other factors determine how long it takes to encode from the software standpoint.

For hardware, the main factor is CPU speed, and to a lesser extent, bus speed, memory speed and drive speeds.

[guns1inger]

There are some vast differences in speed between different encoders encoding to the same standard. Just compare Tmpgenc Plus with CCE or ProCoder to see how big the differences can be. This comes down to several factors, including the colourspace the video is processed in, the amount and type of analysis being done on the image (and a lot of analysis is done on the image when encoding), and the way in which the software is written. Some software languages simply run faster than others or are more efficient.

Sometimes there is a cost to speed. Some of the faster encoders are fast because the cut corners or simplify the way the image analysis is done. While this produces a faster result, it comes at a cost to quality. Sometimes this cost is low, sometimes it is very obvious. The authors of some of this 'faster' software assume that the bulk of the source material being encoded by their software is not of very high quality to begin with, so these compromises are not such a big issues.