how many bits/s should i use?

[sickman2o0o]

hello there,

is there any way or guide or rule that tells me with how many bits/second i should encode to have slim files and good pic qualitiy?

thx in advance

i want to encode my dv cam streams to xvid with virtual dub...

[Lenny_Nero]

One of the problems is what I think looks good and you think looks good might be something very different.

With my DVB-TV card I often aim for around 1000 Kbps (overall) and I think that gives a very good output, I have gone down to just over 570 Kbps for something that had a lot of older lower res clips in it and that still looked good.

I have spent a while running the same thing over and over to find this, I dont know how much that will help you as its not DV, I dont have much DV experience, but I expect that you have a very good signal to work with in the first place, so that should get you off to a good start another thing to try is Auto Gordian Knot, it works really well for the amount of input needed.

[foxyshadis]

In x264 it's pretty easy to find out how much you need, just make an avs with about 1 minute of video, and run a constant quality encode on it on the commandline or in your favorite gui. (This is --crf on the commandline.) Values you should try are from 18 to 26 in steps of 2 or 3. You should quickly find a quality level you prefer that way. The bitrate that quality level uses can vary wildly based on what you encode, though. If you don't have to fit video into a specific size, consider sticking to a quality encode instead of bitrate.

DV will almost always require more bits than DVDs, just because it's jerky, higher framerate, and often badly lit, but judicious preprocessing and proper deinterlacing can reduce that a lot. There are a number of avisynth threads on it.

Oh, you did say xvid, so the tool Enc should help you. See the presets thread.

[Awatef]

But to make it as simple as possible, I would suggest to never go below 0.15 bits per pixel to achieve acceptable quality.
For example, 640x480@25fps would require at least:
(640x480x25x0.15)/1000 = 1152kbps

[SealTooGreat]

Use Aspect (http://aspect.fre3.com/) to calculate bits per pixel. Try between 0.15 - 0.22 , 0.19 should be golden middle.