Imagick::contrastStretchImage

(PECL imagick 2.0.0)

Imagick::contrastStretchImage — Enhances the contrast of a color image

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Imagick::contrastStretchImage ( float $black_point , float $white_point [, int $channel = Imagick::CHANNEL_DEFAULT ] ) : bool

Enhances the contrast of a color image by adjusting the pixels color to span the entire range of colors available. 锟剿凤拷锟斤拷锟斤拷Imagick锟斤拷锟斤拷ImageMagick 6.2.9锟斤拷锟较版本锟斤拷锟斤拷时锟斤拷锟矫★拷

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black_point: The black point.
white_point: The white point.
channel: Provide any channel constant that is valid for your channel mode. To apply to more than one channel, combine channeltype constants using bitwise operators. Imagick::CHANNEL_ALL. Refer to this list of channel constants.

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