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Imagick::transparentPaintImage — Paints pixels transparent
Paints pixels matching the target color transparent. This method is available if Imagick has been compiled against ImageMagick version 6.3.8 or newer.
The target color to paint
The level of transparency: 1.0 is fully opaque and 0.0 is fully transparent.
The amount of fuzz. For example, set fuzz to 10 and the color red at intensities of 100 and 102 respectively are now interpreted as the same color.
TRUEpaints any pixel that does not match the target color.
TRUE on success.