pngtopnm: reading a 640w x 300h image, 8 bits
pngtopnm: truecolor+alpha, not interlaced, base filter
pngtopnm: background {index, gray, red, green, blue} = {0, 0, 0, 0, 0}
pngtopnm: tRNS chunk (transparency): not present
pngtopnm: gAMA chunk (image gamma): not present
pngtopnm: sBIT chunk: present
pngtopnm: cHRM chunk: not present
pngtopnm: PLTE chunk: not present
pngtopnm: bKGD chunk: not present
pngtopnm: hIST chunk: not present
pngtopnm: pHYs chunk: present
pngtopnm: oFFs chunk: not present
pngtopnm: tIME chunk: not present
pngtopnm: pCAL chunk: not present
pngtopnm: sRGB chunk: not present
pngtopnm: writing a PPM file (maxval=255)
pnmremap: 16 colors found in colormap
pnmremap: 0 pixels not matched in color map
192000 pixels, 72905 bytes, (24.06% compression)
#000000=0
#141420=1
#201831=2
#24203d=3
#2d2445=4
#243555=5
#3d3159=6
#ffffff=7
#413561=8
#493d61=9
#314d7d=10
#285596=11
#5d595d=12
#3569b6=13
#9e9a9e=14
#cac6c2=15
pnmtopng: reading a PPM file (maxval=255)
pnmtopng: Finding colors in input image...
pnmtopng: 16 colors found
pnmtopng: reading ordered palette (colormap)...
pnmtopng: 16 colors found
pnmtopng: PNG palette has 16 entries, 0 of them non-opaque
pnmtopng: Writing 4-bit color indexes
pnmtopng: writing a 4-bit palette file