png2cv 0.13 reducing memory usage of pattern and color tables a bit

[PkK]

png2cv 0.13 has been released today and can be downloaded from

http://colecovision.eu/ColecoVision/development/png2cv.shtml

 

Compared to the previous release this version produces outpout more

suitable for compression.

 

Example:

The representation of characters in the ColecoVision has some

redundancy, e.g. swapping the two colors in a line and inverting the

pattern will not change how a line looks on screen. Thus, by swapping

colors the pattern can be inverted and the other way 'round. This can be

used to create longer sequences of identical bytes in the pattern and

color tables, which can be compressed better.

 

Philipp

[newcoleco]

Example:

The representation of characters in the ColecoVision has some

redundancy, e.g. swapping the two colors in a line and inverting the

pattern will not change how a line looks on screen. Thus, by swapping

colors the pattern can be inverted and the other way 'round. This can be

used to create longer sequences of identical bytes in the pattern and

color tables, which can be compressed better.

It's always a good thing to optimize the output. This problem did haunted me during the first years, when I was dealing with BMP2PP and wondering why by default the empty spaces have a green color, so my first tools did decode the picture and try to optimize for compression, like your example suggest. So, I did implement optimization in my own bitmap tools, but I've reccently find out that if there is no real graphic to deal with, my algorithm just crash by looping forever. So, in my more reccent tools, I didn't apply the optimization until I fix the bug.