Does reducing video data rate reduces its size?

[zispalufyo]

what are the effects of reducing data rate..where can i learn more about this..and please suggest a tool/software so i can reduce video size by not loosing its quality.

[_Al_]

Download some H.264 encoder base on x264 encoder , like Handbrake and use 1pass RF encoding (CRF encoding) . Set your video with different RF value, start with 18 I guess. You will see how it works, what size you are going to get. As you increase RF, quality will drop, but overall video size would drop too. This way you might find sweet spot that works for you. We all have different sweet spot for encoding video. It is not universal.

Another way to decrease videosize is to lower video resolution.

[jagabo]

What do you mean by data rate? If you mean bitrate, yes. Regardless of other properties:

stream size = bitrate * running time

This is in fact the definition of bitrate:

bitrate = stream size / running time

File size is the sum of all the stream sizes and a little overhead for the container.

[zispalufyo]

Thank you guys.

[zispalufyo]

about handbrake; i installed latest version and in format i see only mp4/mkv..does anyone know which version of handbrake supported avi output.

[davexnet]

Very old version.
Do you really need AVI ? Why?