(PHP 4, PHP 5)
imagegif — Output image to browser or file
imagegif() creates the GIF file in filename from the image image . The image argument is the return from the imagecreate() or imagecreatefrom* function.
The image format will be GIF87a unless the image has been made transparent with imagecolortransparent(), in which case the image format will be GIF89a.
imagecreatetruecolor() 등의 이미지 생성 함수에서 반환한 이미지 자원.
The path to save the file to. If not set or NULL, the raw image stream will be outputted directly.
성공할 경우 TRUE를, 실패할 경우 FALSE를 반환합니다.
Example #1 Outputting an image using imagegif()
<?php
// Create a new image instance
$im = imagecreatetruecolor(100, 100);
// Make the background white
imagefilledrectangle($im, 0, 0, 99, 99, 0xFFFFFF);
// Draw a text string on the image
imagestring($im, 3, 40, 20, 'GD Library', 0xFFBA00);
// Output the image to browser
header('Content-type: image/gif');
imagegif($im);
imagedestroy($im);
?>
Example #2 Converting a PNG image to GIF using imagegif()
<?php
// Load the PNG
$png = imagecreatefrompng('./php.png');
// Save the image as a GIF
imagegif($png, './php.gif');
// Free from memory
imagedestroy($png);
// We're done
echo 'Converted PNG image to GIF with success!';
?>
Note: Since all GIF support was removed from the GD library in version 1.6, this function is not available if you are using that version of the GD library. Support is expected to return in a version subsequent to the rerelease of GIF support in the GD library in mid 2004. For more information, see the » GD Project site.
The following code snippet allows you to write more portable PHP applications by auto-detecting the type of GD support which is available. Replace the sequence header ("Content-type: image/gif"); imagegif ($im); by the more flexible sequence:<?php
// Create a new image instance
$im = imagecreatetruecolor(100, 100);
// Do some image operations here
// Handle output
if(function_exists('imagegif'))
{
// For GIF
header('Content-type: image/gif');
imagegif($im);
}
elseif(function_exists('imagejpeg'))
{
// For JPEG
header('Content-type: image/jpeg');
imagejpeg($im, NULL, 100);
}
elseif(function_exists('imagepng'))
{
// For PNG
header('Content-type: image/png');
imagepng($im);
}
elseif(function_exists('imagewbmp'))
{
// For WBMP
header('Content-type: image/vnd.wap.wbmp');
imagewbmp($im);
}
else
{
imagedestroy($im);
die('No image support in this PHP server');
}
// If image support was found for one of these
// formats, then free it from memory
if($im)
{
imagedestroy($im);
}
?>
Note: As of PHP 4.0.2 you can use the function imagetypes() in place of function_exists() for checking the presence of the various supported image formats:
<?php
if(imagetypes() & IMG_GIF)
{
header('Content-type: image/gif');
imagegif($im);
}
elseif(imagetypes() & IMG_JPG)
{
/* ... etc. */
}
?>