image_resize() and friends from tellyworth. fixes #6005

git-svn-id: http://svn.automattic.com/wordpress/trunk@7041 1a063a9b-81f0-0310-95a4-ce76da25c4cd
This commit is contained in:
ryan 2008-02-26 18:46:03 +00:00
parent afe0740ba8
commit de3ab9a05e
2 changed files with 134 additions and 20 deletions

View File

@ -227,26 +227,6 @@ function wp_shrink_dimensions( $width, $height, $wmax = 128, $hmax = 96 ) {
return wp_constrain_dimensions( $width, $height, $wmax, $hmax ); return wp_constrain_dimensions( $width, $height, $wmax, $hmax );
} }
// same as wp_shrink_dimensions, except the max parameters are optional.
// if either width or height are empty, no constraint is applied on that dimension.
function wp_constrain_dimensions( $current_width, $current_height, $max_width=0, $max_height=0 ) {
if ( !$max_width and !$max_height )
return array( $current_width, $current_height );
$width_ratio = $height_ratio = 1.0;
if ( $max_width > 0 && $current_width > $max_width )
$width_ratio = $max_width / $current_width;
if ( $max_height > 0 && $current_height > $max_height )
$height_ratio = $max_height / $current_height;
// the smaller ratio is the one we need to fit it to the constraining box
$ratio = min( $width_ratio, $height_ratio );
return array( intval($current_width * $ratio), intval($current_height * $ratio) );
}
// convert a fraction string to a decimal // convert a fraction string to a decimal
function wp_exif_frac2dec($str) { function wp_exif_frac2dec($str) {
@list( $n, $d ) = explode( '/', $str ); @list( $n, $d ) = explode( '/', $str );

View File

@ -92,4 +92,138 @@ function get_image_tag($id, $alt, $title, $align, $rel = false, $size='medium')
return $html; return $html;
} }
// same as wp_shrink_dimensions, except the max parameters are optional.
// if either width or height are empty, no constraint is applied on that dimension.
function wp_constrain_dimensions( $current_width, $current_height, $max_width=0, $max_height=0 ) {
if ( !$max_width and !$max_height )
return array( $current_width, $current_height );
$width_ratio = $height_ratio = 1.0;
if ( $max_width > 0 && $current_width > $max_width )
$width_ratio = $max_width / $current_width;
if ( $max_height > 0 && $current_height > $max_height )
$height_ratio = $max_height / $current_height;
// the smaller ratio is the one we need to fit it to the constraining box
$ratio = min( $width_ratio, $height_ratio );
return array( intval($current_width * $ratio), intval($current_height * $ratio) );
}
// calculate dimensions and coordinates for a resized image that fits within a specified width and height
// if $crop is true, the largest matching central portion of the image will be cropped out and resized to the required size
function image_resize_dimensions($orig_w, $orig_h, $dest_w, $dest_h, $crop=false) {
if ($orig_w <= 0 || $orig_h <= 0)
return false;
// at least one of dest_w or dest_h must be specific
if ($dest_w <= 0 && $dest_h <= 0)
return false;
if ( $crop ) {
// crop the largest possible portion of the original image that we can size to $dest_w x $dest_h
$aspect_ratio = $orig_w / $orig_h;
$new_w = min($dest_w, $orig_w);
$new_h = min($dest_h, $orig_h);
if (!$new_w) {
$new_w = intval($new_h * $aspect_ratio);
}
if (!$new_h) {
$new_h = intval($new_w / $aspect_ratio);
}
$size_ratio = max($new_w / $orig_w, $new_h / $orig_h);
$crop_w = ceil($new_w / $size_ratio);
$crop_h = ceil($new_h / $size_ratio);
$s_x = floor(($orig_w - $crop_w)/2);
$s_y = floor(($orig_h - $crop_h)/2);
}
else {
// don't crop, just resize using $dest_w x $dest_h as a maximum bounding box
$crop_w = $orig_w;
$crop_h = $orig_h;
$s_x = 0;
$s_y = 0;
list( $new_w, $new_h ) = wp_constrain_dimensions( $orig_w, $orig_h, $dest_w, $dest_h );
}
// if the resulting image would be the same size or larger we don't want to resize it
if ($new_w >= $orig_w && $new_h >= $orig_h)
return false;
// the return array matches the parameters to imagecopyresampled()
// int dst_x, int dst_y, int src_x, int src_y, int dst_w, int dst_h, int src_w, int src_h
return array(0, 0, $s_x, $s_y, $new_w, $new_h, $crop_w, $crop_h);
}
// Scale down an image to fit a particular size and save a new copy of the image
function image_resize( $file, $max_w, $max_h, $crop=false, $suffix=null, $dest_path=null, $jpeg_quality=75) {
$image = wp_load_image( $file );
if ( !is_resource( $image ) )
return new WP_Error('error_loading_image', $image);
list($orig_w, $orig_h, $orig_type) = getimagesize( $file );
$dims = image_resize_dimensions($orig_w, $orig_h, $max_w, $max_h, $crop);
if (!$dims)
return $dims;
list($dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h) = $dims;
$newimage = imagecreatetruecolor( $dst_w, $dst_h);
// preserve PNG transparency
if ( IMAGETYPE_PNG == $orig_type && function_exists( 'imagealphablending' ) && function_exists( 'imagesavealpha' ) ) {
imagealphablending( $newimage, false);
imagesavealpha( $newimage, true);
}
imagecopyresampled( $newimage, $image, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h);
// we don't need the original in memory anymore
imagedestroy( $image );
// $suffix will be appended to the destination filename, just before the extension
if ( !$suffix )
$suffix = "{$dst_w}x{$dst_h}";
$info = pathinfo($file);
$dir = $info['dirname'];
$ext = $info['extension'];
$name = basename($file, ".{$ext}");
if ( !is_null($dest_path) and $_dest_path = realpath($dest_path) )
$dir = $_dest_path;
$destfilename = "{$dir}/{$name}-{$suffix}.{$ext}";
if ( $orig_type == IMAGETYPE_GIF ) {
if (!imagegif( $newimage, $destfilename ) )
return new WP_Error('resize_path_invalid', __( 'Resize path invalid' ));
}
elseif ( $orig_type == IMAGETYPE_PNG ) {
if (!imagepng( $newimage, $destfilename ) )
return new WP_Error('resize_path_invalid', __( 'Resize path invalid' ));
}
else {
// all other formats are converted to jpg
$destfilename = "{$dir}/{$name}-{$suffix}.jpg";
if (!imagejpeg( $newimage, $destfilename, $jpeg_quality ) )
return new WP_Error('resize_path_invalid', __( 'Resize path invalid' ));
}
imagedestroy( $newimage );
// Set correct file permissions
$stat = stat( dirname( $destfilename ));
$perms = $stat['mode'] & 0000666; //same permissions as parent folder, strip off the executable bits
@ chmod( $destfilename, $perms );
return $destfilename;
}
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