pngtopnm: reading a 640w x 480h 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: 14 colors found in colormap
pnmremap: 0 pixels not matched in color map
ppmtoxpm: (Computing colormap...
ppmtoxpm: ...Done.  14 colors found.)