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@NogDogJul 22.2010 — #I don't know if this will help, but it's the resizing function I use on this page :
@NogDogJul 23.2010 — #Resampled tends to produce a better-looking result, probably at the expense of a bit extra processing. @NogDogJul 23.2010 — #To use my function in post #4, you'd simply need to do something like:
I need help cropping an image using GD
I want to crop a 80×80 thumbnail from the center of an image using GD. I am currently using the function below, which I copied from [URL=”http://911-need-code-help.blogspot.com/2008/10/resize-images-using-phpgd-library.html”]http://911-need-code-help.blogspot.com/2008/10/resize-images-using-phpgd-library.html
Is there a way to resize the image smaller than 80×80 to 80x(a number larger than 80) and then crop 80×80 from the center of the image?
For example, if the image is 80×40, then it gets resized to 160×80. Then, 80×80 is cropped from it.
Or, if there’s an easier way to get an 80×80 thumbnail, can someone provide an example? Thanks in advance.
The following the function I’m currently using:
[code=php] define( ‘THUMBNAIL_IMAGE_MAX_WIDTH’, 80 );
define( ‘THUMBNAIL_IMAGE_MAX_HEIGHT’, 80 );
function generate_image_thumbnail( $source_image_path, $thumbnail_image_path )
{
list( $source_image_width, $source_image_height, $source_image_type ) = getimagesize( $source_image_path );
switch ( $source_image_type )
{
case IMAGETYPE_GIF:
$source_gd_image = imagecreatefromgif( $source_image_path );
break;
case IMAGETYPE_JPEG:
$source_gd_image = imagecreatefromjpeg( $source_image_path );
break;
case IMAGETYPE_PNG:
$source_gd_image = imagecreatefrompng( $source_image_path );
break;
}
if ( $source_gd_image === false )
{
return false;
}
$thumbnail_image_width = THUMBNAIL_IMAGE_MAX_WIDTH;
$thumbnail_image_height = THUMBNAIL_IMAGE_MAX_HEIGHT;
$source_aspect_ratio = $source_image_width / $source_image_height;
$thumbnail_aspect_ratio = $thumbnail_image_width / $thumbnail_image_height;
$thumbnail_small_width = $thumbnail_image_width / $source_image_width;
$thumbnail_small_height = $thumbnail_image_height / $source_image_height;
if ( $source_image_width <= $thumbnail_image_width && $source_image_height <= $thumbnail_image_height )
{
$thumbnail_image_width = $source_image_width * $thumbnail_small_width;
$thumbnail_image_height = $source_image_height * $thumbnail_small_height;
}
if ( $thumbnail_aspect_ratio > $source_aspect_ratio )
{
//I think the math needs to be edited here
$thumbnail_image_width = ( int ) ( $thumbnail_image_height * $source_aspect_ratio );
}
else
{
//It needs to be edited here as well
$thumbnail_image_height = ( int ) ( $thumbnail_image_width / $source_aspect_ratio );
}
$thumbnail_gd_image = imagecreatetruecolor( $thumbnail_image_width, $thumbnail_image_height );
imagecopyresampled( $thumbnail_gd_image, $source_gd_image, 0, 0, 0, 0, $thumbnail_image_width, $thumbnail_image_height, $source_image_width, $source_image_height );
imagejpeg( $thumbnail_gd_image, $thumbnail_image_path, 90 );
imagedestroy( $source_gd_image );
imagedestroy( $thumbnail_gd_image );
return true;
}
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@NogDogJul 22.2010 — #I don't know if this will help, but it's the resizing function I use on [code=php]
/**
* Resize image
* @return mixed Image resource, or boolean false
* @param resource Image resource
* @param int width
* @param int height
*/
function resize($imgFile, $width, $height, &$error = null)
{
$attrs = @getimagesize($imgFile);
if($attrs == false or $attrs[2] != IMG_JPEG)
{
$error = "Uploaded image is not JPEG or is not readable by this page.";
return false;
}
if($attrs[0] * $attrs[1] > 3000000)
{
$error = "Max pixels allowed is 3,000,000. Your {$attrs[0]} x " .
"{$attrs[1]} image has " . $attrs[0] * $attrs[1] . " pixels.";
return false;
}
$ratio = (($attrs[0] / $attrs[1]) < ($width / $height)) ?
$width / $attrs[0] : $height / $attrs[1];
$x = max(0, round($attrs[0] / 2 - ($width / 2) / $ratio));
$y = max(0, round($attrs[1] / 2 - ($height / 2) / $ratio));
$src = imagecreatefromjpeg($imgFile);
if($src == false)
{
$error = "Unknown problem trying to open uploaded image.";
return false;
}
$resized = imagecreatetruecolor($width, $height);
$result = imagecopyresampled($resized, $src, 0, 0, $x, $y, $width, $height,
round($width / $ratio, 0), round($height / $ratio));
if($result == false)
{
$error = "Error trying to resize and crop image.";
return false;
}
else
{
return $resized;
}
}[/code]0
@NogDogJul 23.2010 — #0
@NogDogJul 23.2010 — #To use my function in post #4, you'd simply need to do something like:[code=php]
$sourceImage = imagecreatefromjpeg($filename);
// add some error-checking in case the above fails, then...
$thumbnail = resize($sourceImage, 80, 80, $error);
if($thumbnail == false) {
die($error); // or whatever you want to do if it fails
}
else {
// do whatever you want to do with $thumbnail
}
[/code]