Did I find the right examples for you? yes no

All Samples(3)  |  Call(0)  |  Derive(0)  |  Import(3)
KISS indexed PNG.

following:
http://www.libpng.org/pub/png/spec/1.2/

src/s/k/skimpyGimpy-1.4/skimpyGimpy/skimpyGimpy.py   skimpyGimpy(Download)
    def formatPNG(this, filename, color=(0x77, 0x77, 0x77), scale=2):
        import KiPNG
        this.prepare()
        pD = this.pixelDict
        D = {}

src/s/k/skimpyGimpy-1.4/skimpyGimpy/canvas.py   skimpyGimpy(Download)
    def dumpToPNG(this, filename):
        import KiPNG
        this.filename = filename
        if not this.pixels:
            raise ValueError, "no pixels plotted"

src/s/k/skimpyGimpy-1.4/skimpyGimpy/bdf.py   skimpyGimpy(Download)
    def toPNG(this, filename, color=(0x0f,0x11,0xaf), scale=2, speckle=0.3):
        import KiPNG
        D = this.pixelDict()
        return KiPNG.DictToPNG(D, filename, color, scale, speckle)