ppm2rgba
rgba2ppm
rgbaadd
rgbaaddB
rgbaautocrop
rgbadither
rgbafade
rgbamerge
rgbamergeB
rgbaquant
rgbascale
rgbascaleB
rgbascaleF
rgbasub
rgbasubB
rgbatrans
the RGBA32 manual and style guide: troubleshooting
It segfaulted!
A few bugs remain, especially when dealing with command line parsing, but the most likely cause of a segfault is exhausting virtual memory. Constructing a long filter pipeline can sink alot of memory. Even a single full-screen image can blow away all the VM small machines can muster.I keep getting white or light colored areas that I didn't make
When converting back to ppm, any transparent areas are treated as if in front of a white background. To avoid this, either merge the image with an opaque background or usergbatrans -1 100%
rgbascale or rgbascaleF takes forever!
rgbascaleF (and rgbascale when expanding) performs a fourier transform of the entire image; an image with large prime or nearly prime dimensions can take thousands of times longer than an image with dimensions consisting of small factors.rgbaquant or rgbadither doesn't use as many colors as specified on the command line
Both of these utilities use greedy algorithms that make the best guesses they can about colors as they proceed. Although they will never produce an image that uses more colors than requested, they may well produce an image that uses less.A large number of colors 'disappeared'
Transparent areas still possess color; it's just not visible. This is likely where all the colors are.The image is mottled or has ripples after scaling
The scaling was likely done in the fourier domain. Rgbascale and rgbascaleB will still use fourier scaling is one or both of the axes is larger than the original image. Ringing can be an artifact of fourier scaling.ppm2rgba reports an unknown or unsupported format
All PPM/PGM/PBM files begin with the letter 'P' followed by a digit; if you don't see this, the input is *not* PPM/PGM/PBM. If ppm2rgba reports an unsupported PPM variant, chances are you've got a 'P1' or 'P2' file which is an ASCII PBM/PGM file. I've never actually seen one in use, so RGBA32 doesn't support them. Convert the file to raw format, then ppm2rgba can read it.rgbaautocrop won't crop the image
The background is probably not solid, but consists of a number of nearly indistinguishable colors. Rgbaautocrop can only crop absolutely solid backgrounds.The transparent areas in an image weren't transparent when overlayed onto another image
The areas weren't transparent. White and black (and any other color) are transparent only if they are made transparent using rgbatrans or rgbafade.
