18.12 Making an Image Interlaced

You want to make an image interlaced, meaning that it will load in multiple scans .

Technique

Use the ImageInterlace() function on an image stream:

 <?php header("Content-type: image/gif"); $im = ImageCreate(100, 20); ImageInterlace($im, 1); $white = ImageColorAllocate($im, 255, 255, 255); ImageColorTransparent($im, $white); $light_red = ImageColorAllocate($im, 233, 93, 20); ImageArc($im, 4, 5, 50, 40, 10, 180, $light_red); ImageGif($im); ImageDestroy($im); ?> 

Comments

The ImageInterlace() function enables you to set whether an image stream is interlaced. If the second argument of ImageInterlace() is true ( 1 ), the image is interlaced; otherwise , the image is not interlaced. By default, images are not interlaced.

If the second argument is not provided to the ImageInterlace() function, the function simply returns whether the image is currently interlaced.