i tried this convert w1.png -format %c -depth 8 histogram:info:- on my transparent png and got this 988644: ( 0, 0, 0, 0) #00000000 none 1019: ( 0, 0,255,255) #0000FF blue 301: ( 0,128,204,255) #0080CC rgba(0,128,204,1) 1284: ( 0,184, 0,255) #00B800 rgba(0,184,0,1) 325: ( 0,255, 0,255) #00FF00 lime ...