Video Bitrate???

[sceeme]

What exactly does it mean when it says in NFO's, 3.9mbps 9 passes?? Is tht good? what should i be looking for?

[Baldrick]

you should not download dvds. buy or rent them.

[jagabo]

It means the video has an average bitrate of 3.9 megabits per second and was created using 9 passes. With multipass encoding the picture quality is refined with each pass. But beyond 2 or 3 you get vastly diminishing returns. So somebody really overdid it.

[jimmalenko]

you should not download dvds. buy or rent them.

What about all those "public domain" or "homemade" DVDs available for download that we deal with here on a daily basis ? <snigger, snigger>

[Baldrick]

forgot those, ignore my last comment.

[sceeme]

so am i right in saying that the higher the bitrate and lower the passes, the better the quality?

Is there anyway of checking this info when there is no NFO?

[guns1inger]

Look up bitrate viewers in the Tools section to see the bitrate. Nothing will tell you the number of passes after the fact, but it doesn't really matter. What matters is the quality of the picture. If you want quality, don't download.

[jagabo]

In general, the higher the bitrate, the higher the quality. But there are many other factors that influence the quality. For example, some codecs require more bitrate than others. An MPEG 2 video at 2500 kbps will probably look worse than the same video encoded MPEG 4 at 2000 kbps. An MPEG 2 file with a variable bitrate will look better than another at the same, but constant, bitrate.

With multipass encoding, each pass adds quality to the result. Say a 2-pass encoding takes 2 hours and gives you 95 percent "quality". A 3-pass encode will take 3 hours and might get you 99.5 percent. A 4-pass encode will take 4 hours and might get you 99.95 percent. Etc. So the quality may be getting better with each pass but amount by which it is improving gets to be so small as to be insignificant. Whereas the time spent encoding is getting longer and longer.