Switches of ffmpeg: -s -aspect

[David1105]

In the following commandline for ffmpeg, both "-s" and "-apsect" are set, could someone explain what's the purpose of doing these two settings here, particularly that 352/256 is not equal to 4/3?

ffmpeg -i "bob1.avi" -s 352x256 -aspect 4:3 -padtop 16 -padbottom 16 -aspect 4:3 -vframes 30 "bob1.mpg"

Thanks!

[foxyshadis]

-s actually resizes the pixels. -aspect sets the flags to display it as that ratio, no matter what actual pixel size you use.

-s 640x16 -aspect 4:3 is perfectly valid, and it'll save a lot of space... but it'll sure be blurry.