Created
November 29, 2011 18:24
-
-
Save anonymous/1405838 to your computer and use it in GitHub Desktop.
WordPress: Set an image's crop position and rotates based on EXIF information if necessary
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
<?php | |
bt_add_image_size( 'product-screenshot', 300, 300, array( 'left', 'top' ) ); | |
bt_add_image_size( 'product-feature', 460, 345, array( 'center', 'top' ) ); | |
add_filter( 'intermediate_image_sizes_advanced', 'bt_intermediate_image_sizes_advanced' ); | |
add_filter( 'wp_generate_attachment_metadata', 'bt_generate_attachment_metadata', 10, 2 ); | |
/** | |
* Registers a new image size with cropping positions | |
* | |
* The $crop parameter works as in the 'add_image_size' function taking true or | |
* false values. If set to true, the default cropping position is 'center', 'center'. | |
* | |
* The $crop parameter also takes an array of the format | |
* array( x_crop_position, y_crop_position ) | |
* x_crop_position can be 'left', 'center', 'right' | |
* y_crop_position can be 'top', 'center', 'bottom' | |
* | |
* @param string $name Image size identifier. | |
* @param int $width Image width. | |
* @param int $height Image height. | |
* @param bool|array $crop Optional, default is false. Whether to crop image to specified height and width or resize. An array can specify positioning of the crop area. | |
* @return bool|array False, if no image was created. Metadata array on success. | |
*/ | |
function bt_add_image_size( $name, $width = 0, $height = 0, $crop = false ) { | |
global $_wp_additional_image_sizes; | |
$_wp_additional_image_sizes[$name] = array( 'width' => absint( $width ), 'height' => absint( $height ), 'crop' => $crop ); | |
} | |
/** | |
* Returning no sizes (an empty array) will force | |
* wp_generate_attachment_metadata to skip creating intermediate image sizes on | |
* upload, then we can run our own resizing functions by hooking into the | |
* 'wp_generate_attachment_metadata' filter | |
*/ | |
function bt_intermediate_image_sizes_advanced( $sizes ) { | |
return array(); | |
} | |
function bt_generate_attachment_metadata( $metadata, $attachment_id ) { | |
$attachment = get_post( $attachment_id ); | |
$uploadPath = wp_upload_dir(); | |
$file = path_join($uploadPath['basedir'], $metadata['file']); | |
if ( !preg_match('!^image/!', get_post_mime_type( $attachment )) || !file_is_displayable_image( $file ) ) return $metadata; | |
global $_wp_additional_image_sizes; | |
foreach ( get_intermediate_image_sizes() as $s ) { | |
$sizes[$s] = array( 'width' => '', 'height' => '', 'crop' => FALSE ); | |
if ( isset( $_wp_additional_image_sizes[$s]['width'] ) ) | |
$sizes[$s]['width'] = intval( $_wp_additional_image_sizes[$s]['width'] ); // For theme-added sizes | |
else | |
$sizes[$s]['width'] = get_option( "{$s}_size_w" ); // For default sizes set in options | |
if ( isset( $_wp_additional_image_sizes[$s]['height'] ) ) | |
$sizes[$s]['height'] = intval( $_wp_additional_image_sizes[$s]['height'] ); // For theme-added sizes | |
else | |
$sizes[$s]['height'] = get_option( "{$s}_size_h" ); // For default sizes set in options | |
if ( isset( $_wp_additional_image_sizes[$s]['crop'] ) ) | |
$sizes[$s]['crop'] = $_wp_additional_image_sizes[$s]['crop']; | |
else | |
$sizes[$s]['crop'] = get_option( "{$s}_crop" ); | |
} | |
foreach ( $sizes as $size => $size_data ) { | |
$resized = bt_image_make_intermediate_size( $file, $size_data['width'], $size_data['height'], $size_data['crop'] ); | |
if ( $resized ) | |
$metadata['sizes'][$size] = $resized; | |
} | |
return $metadata; | |
} | |
/** | |
* Resize an image to make a thumbnail or intermediate size. | |
* | |
* The returned array has the file size, the image width, and image height. The | |
* filter 'image_make_intermediate_size' can be used to hook in and change the | |
* values of the returned array. The only parameter is the resized file path. | |
* | |
* @param string $file File path. | |
* @param int $width Image width. | |
* @param int $height Image height. | |
* @param bool|array $crop Optional, default is false. Whether to crop image to specified height and width or resize. An array can specify positioning of the crop area. | |
* @return bool|array False, if no image was created. Metadata array on success. | |
*/ | |
function bt_image_make_intermediate_size( $file, $width, $height, $crop = false ) { | |
if ( $width || $height ) { | |
$resized_file = bt_image_resize( $file, $width, $height, $crop, null, null, 90 ); | |
if ( !is_wp_error( $resized_file ) && $resized_file && $info = getimagesize( $resized_file ) ) { | |
$resized_file = apply_filters('image_make_intermediate_size', $resized_file); | |
return array( | |
'file' => wp_basename( $resized_file ), | |
'width' => $info[0], | |
'height' => $info[1], | |
); | |
} | |
} | |
return false; | |
} | |
/** | |
* Retrieve calculated resized dimensions for use in imagecopyresampled(). | |
* | |
* 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. | |
* | |
* @param int $orig_w Original width. | |
* @param int $orig_h Original height. | |
* @param int $dest_w New width. | |
* @param int $dest_h New height. | |
* @param bool $crop Optional, default is false. Whether to crop image or resize. | |
* @return bool|array False, on failure. Returned array matches parameters for imagecopyresampled() PHP function. | |
*/ | |
function bt_image_resize_dimensions($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); | |
$crop_w = round($new_w / $size_ratio); | |
$crop_h = round($new_h / $size_ratio); | |
if ( !is_array( $crop ) || count( $crop ) != 2 ) { | |
$crop = apply_filters( 'image_resize_crop_default', array( 'center', 'center' ) ); | |
} | |
switch ( $crop[0] ) { | |
case 'left': $s_x = 0; break; | |
case 'right': $s_x = $orig_w - $crop_w; break; | |
default: $s_x = floor( ( $orig_w - $crop_w ) / 2 ); | |
} | |
switch ( $crop[1] ) { | |
case 'top': $s_y = 0; break; | |
case 'bottom': $s_y = $orig_h - $crop_h; break; | |
default: $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, (int) $s_x, (int) $s_y, (int) $new_w, (int) $new_h, (int) $crop_w, (int) $crop_h ); | |
} | |
/** | |
* Scale down an image to fit a particular size and save a new copy of the image. | |
* | |
* The PNG transparency will be preserved using the function, as well as the | |
* image type. If the file going in is PNG, then the resized image is going to | |
* be PNG. The only supported image types are PNG, GIF, and JPEG. | |
* | |
* Some functionality requires API to exist, so some PHP version may lose out | |
* support. This is not the fault of WordPress (where functionality is | |
* downgraded, not actual defects), but of your PHP version. | |
* | |
* @since 2.5.0 | |
* | |
* @param string $file Image file path. | |
* @param int $max_w Maximum width to resize to. | |
* @param int $max_h Maximum height to resize to. | |
* @param bool $crop Optional. Whether to crop image or resize. | |
* @param string $suffix Optional. File Suffix. | |
* @param string $dest_path Optional. New image file path. | |
* @param int $jpeg_quality Optional, default is 90. Image quality percentage. | |
* @return mixed WP_Error on failure. String with new destination path. | |
*/ | |
function bt_image_resize( $file, $max_w, $max_h, $crop = false, $suffix = null, $dest_path = null, $jpeg_quality = 90 ) { | |
$image = wp_load_image( $file ); | |
if ( !is_resource( $image ) ) | |
return new WP_Error( 'error_loading_image', $image, $file ); | |
$size = @getimagesize( $file ); | |
if ( !$size ) | |
return new WP_Error('invalid_image', __('Could not read image size'), $file); | |
list($orig_w, $orig_h, $orig_type) = $size; | |
// Rotate if EXIF 'Orientation' is set | |
// This code is from the reverted patch at | |
// http://core.trac.wordpress.org/changeset/11746/trunk/wp-includes/media.php | |
$rotate = false; | |
if ( is_callable( 'exif_read_data' ) && in_array( $orig_type, apply_filters( 'wp_read_image_metadata_types', array( IMAGETYPE_JPEG, IMAGETYPE_TIFF_II, IMAGETYPE_TIFF_MM ) ) ) ) { | |
$exif = @exif_read_data( $file, null, true ); | |
if ( $exif && isset( $exif['IFD0'] ) && is_array( $exif['IFD0'] ) && isset( $exif['IFD0']['Orientation'] ) ) { | |
if ( 6 == $exif['IFD0']['Orientation'] ) | |
$rotate = 90; | |
elseif ( 8 == $exif['IFD0']['Orientation'] ) | |
$rotate = 270; | |
} | |
} | |
if ( $rotate ) | |
list($max_h,$max_w) = array($max_w,$max_h); | |
$dims = bt_image_resize_dimensions($orig_w, $orig_h, $max_w, $max_h, $crop); | |
if ( !$dims ) | |
return new WP_Error( 'error_getting_dimensions', __('Could not calculate resized image dimensions') ); | |
list($dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h) = $dims; | |
$newimage = wp_imagecreatetruecolor( $dst_w, $dst_h ); | |
if ( $rotate ) | |
list($src_y,$src_x) = array($src_x,$src_y); | |
imagecopyresampled( $newimage, $image, $dst_x, $dst_y, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h); | |
// convert from full colors to index colors, like original PNG. | |
if ( IMAGETYPE_PNG == $orig_type && function_exists('imageistruecolor') && !imageistruecolor( $image ) ) | |
imagetruecolortopalette( $newimage, false, imagecolorstotal( $image ) ); | |
// 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 ) { | |
if ( $rotate ) | |
$suffix = "{$dst_h}x{$dst_w}"; | |
else | |
$suffix = "{$dst_w}x{$dst_h}"; | |
} | |
$info = pathinfo($file); | |
$dir = $info['dirname']; | |
$ext = $info['extension']; | |
$name = wp_basename($file, ".$ext"); | |
if ( !is_null($dest_path) and $_dest_path = realpath($dest_path) ) | |
$dir = $_dest_path; | |
$destfilename = "{$dir}/{$name}-{$suffix}.{$ext}"; | |
if ( IMAGETYPE_GIF == $orig_type ) { | |
if ( !imagegif( $newimage, $destfilename ) ) | |
return new WP_Error('resize_path_invalid', __( 'Resize path invalid' )); | |
} elseif ( IMAGETYPE_PNG == $orig_type ) { | |
if ( !imagepng( $newimage, $destfilename ) ) | |
return new WP_Error('resize_path_invalid', __( 'Resize path invalid' )); | |
} else { | |
if ( $rotate ) { | |
$newimage = _rotate_image_resource( $newimage, 360 - $rotate ); | |
} | |
// all other formats are converted to jpg | |
$destfilename = "{$dir}/{$name}-{$suffix}.jpg"; | |
$return = imagejpeg( $newimage, $destfilename, apply_filters( 'jpeg_quality', $jpeg_quality, 'image_resize' ) ); | |
if ( !$return ) | |
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; | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment