[magick-users] Selecting GIF Type for compression

[Kris]

Dear,

i build up Proxy server + Imagemagick compression for internal use. It 
was working nice on JPEG and PNG files.

for JPEG i did reducing quality
for PNG i did conversion to JPG
for GIF i got problem.

There 3 types of GIF Image i ever seen :
1. normal picture <= no problem if i convert to JPG
2. moving picture <= i was using "identify" command to check how many 
lines, if more than 1 then will skip it before convert to JPG
3. normal picture + transparent background <= i got problem on this. any 
idea howto check that the image use transparent background ? because 
when i converted it to JPG, i got white background >.<

any idea or clue ?  very thx before