Imagick::contrastImage
Imagick::convolveImage
The Imagick class
PHP Manual

# Imagick::contrastStretchImage

(PECL imagick 2.0.0)

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

### 설명

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

Enhances the contrast of a color image by adjusting the pixels color to span the entire range of colors available. 이 메쏘드는 Imagick을 ImageMagick 6.2.9 이상으로 컴파일 했을 때만 사용할 수 있습니다.

### 인수

`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.

### 반환값

성공시에 `TRUE`를 반환합니다.

Imagick::contrastImage
Imagick::convolveImage
The Imagick class
PHP Manual