Imagick::optimizeImageLayers()

(PECL imagick 2.0.0)

Removes repeated portions of images to optimize

说明

Imagick::optimizeImageLayers(void): bool

Compares each image the GIF disposed forms of the previous image in the sequence. From this it attempts to select the smallest cropped image to replace each frame, while preserving the results of the animation.此方法在Imagick基于ImageMagick 6.2.9以上版本编译时可用。

返回值

成功时返回TRUE。

错误／异常

错误时抛出 ImagickException。

范例

Example #1 Using Imagick::optimizeImageLayers()

Reading, optimizing and writing a GIF image

<?php
/* create new imagick object */
$im = new Imagick("test.gif");
/* optimize the image layers */
$im->optimizeImageLayers();
/* write the image back */
$im->writeImages("test_optimized.gif", true);
?>

参见

• Imagick::compareImageLayers() Returns the maximum bounding region between images
• Imagick::writeImages() Writes an image or image sequence
• Imagick::writeImage() 把图片写入指定的文件

In imagick 3.x (have not checked 2.x), this returns an imagemagick object and not a boolean.
<?php
$image = new Imagick('myanimation.gif');
$image = $image->optimizeImageLayers(); //Does not return a boolean!
$image->writeImage('optimized.gif');