reading non-consecutive frames and single colour channels using mmreader / read

Dear all,

I'm using mmreader / read to access frames in a stored AVI movie. There are two things which would be extremely helpful:

1. Can I read non-consecutive frames in a batch (e.g. only every 5th frame) in one command, or must I loop? Unfortunately, the frame range parameter of "read" only accepts a 1- or 2-element input with frame number or range.

2. Is it possible to read only one of the 3 colour channels (e.g. read only R of the RGB)?

Thanks!

Gilad