[飛鷹]

Pls teach me, thx

[loyukfai]

If you use Windows XP, have a look at the following link:

http://graphicssoft.about.com/cs/digitalphototips/ht/emailpicsxp.htm

[kkkleung]

Two ways:
1) Change the resolution or frame rate without or little compression.
2) Convert it into MPEG4 format by "MPEG4 direct maker". In this way, the resolution can be kept as the original one with MPEG4 compression. The file size typically can be 6 times as small as the motion JPEG compressed file.

[loyukfai]

Oh... Thought it was pictures... kkkleung's suggestions are right, BTW, DivX and its variant codecs are very popular and effective as well.