WordPress/wp-admin/includes/image.php

342 lines
12 KiB
PHP

<?php
/**
* File contains all the administration image manipulation functions.
*
* @package WordPress
* @subpackage Administration
*/
/**
* Create a thumbnail from an Image given a maximum side size.
*
* This function can handle most image file formats which PHP supports. If PHP
* does not have the functionality to save in a file of the same format, the
* thumbnail will be created as a jpeg.
*
* @since 1.2.0
*
* @param mixed $file Filename of the original image, Or attachment id.
* @param int $max_side Maximum length of a single side for the thumbnail.
* @param mixed $deprecated Never used.
* @return string Thumbnail path on success, Error string on failure.
*/
function wp_create_thumbnail( $file, $max_side, $deprecated = '' ) {
if ( !empty( $deprecated ) )
_deprecated_argument( __FUNCTION__, '1.2' );
$thumbpath = image_resize( $file, $max_side, $max_side );
return apply_filters( 'wp_create_thumbnail', $thumbpath );
}
/**
* Crop an Image to a given size.
*
* @since 2.1.0
*
* @param string|int $src_file The source file or Attachment ID.
* @param int $src_x The start x position to crop from.
* @param int $src_y The start y position to crop from.
* @param int $src_w The width to crop.
* @param int $src_h The height to crop.
* @param int $dst_w The destination width.
* @param int $dst_h The destination height.
* @param int $src_abs Optional. If the source crop points are absolute.
* @param string $dst_file Optional. The destination file to write to.
* @return string|WP_Error|false New filepath on success, WP_Error or false on failure.
*/
function wp_crop_image( $src_file, $src_x, $src_y, $src_w, $src_h, $dst_w, $dst_h, $src_abs = false, $dst_file = false ) {
if ( is_numeric( $src_file ) ) // Handle int as attachment ID
$src_file = get_attached_file( $src_file );
$src = wp_load_image( $src_file );
if ( !is_resource( $src ) )
return new WP_Error( 'error_loading_image', $src, $src_file );
$dst = wp_imagecreatetruecolor( $dst_w, $dst_h );
if ( $src_abs ) {
$src_w -= $src_x;
$src_h -= $src_y;
}
if (function_exists('imageantialias'))
imageantialias( $dst, true );
imagecopyresampled( $dst, $src, 0, 0, $src_x, $src_y, $dst_w, $dst_h, $src_w, $src_h );
imagedestroy( $src ); // Free up memory
if ( ! $dst_file )
$dst_file = str_replace( basename( $src_file ), 'cropped-' . basename( $src_file ), $src_file );
$dst_file = preg_replace( '/\\.[^\\.]+$/', '.jpg', $dst_file );
if ( imagejpeg( $dst, $dst_file, apply_filters( 'jpeg_quality', 90, 'wp_crop_image' ) ) )
return $dst_file;
else
return false;
}
/**
* Generate post thumbnail attachment meta data.
*
* @since 2.1.0
*
* @param int $attachment_id Attachment Id to process.
* @param string $file Filepath of the Attached image.
* @return mixed Metadata for attachment.
*/
function wp_generate_attachment_metadata( $attachment_id, $file ) {
$attachment = get_post( $attachment_id );
$metadata = array();
if ( preg_match('!^image/!', get_post_mime_type( $attachment )) && file_is_displayable_image($file) ) {
$imagesize = getimagesize( $file );
$metadata['width'] = $imagesize[0];
$metadata['height'] = $imagesize[1];
list($uwidth, $uheight) = wp_constrain_dimensions($metadata['width'], $metadata['height'], 128, 96);
$metadata['hwstring_small'] = "height='$uheight' width='$uwidth'";
// Make the file path relative to the upload dir
$metadata['file'] = _wp_relative_upload_path($file);
// make thumbnails and other intermediate sizes
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'] = intval( $_wp_additional_image_sizes[$s]['crop'] ); // For theme-added sizes
else
$sizes[$s]['crop'] = get_option( "{$s}_crop" ); // For default sizes set in options
}
$sizes = apply_filters( 'intermediate_image_sizes_advanced', $sizes );
foreach ($sizes as $size => $size_data ) {
$resized = image_make_intermediate_size( $file, $size_data['width'], $size_data['height'], $size_data['crop'] );
if ( $resized )
$metadata['sizes'][$size] = $resized;
}
// fetch additional metadata from exif/iptc
$image_meta = wp_read_image_metadata( $file );
if ( $image_meta )
$metadata['image_meta'] = $image_meta;
}
return apply_filters( 'wp_generate_attachment_metadata', $metadata, $attachment_id );
}
/**
* Calculated the new dimensions for a downsampled image.
*
* @since 2.0.0
* @see wp_constrain_dimensions()
*
* @param int $width Current width of the image
* @param int $height Current height of the image
* @return mixed Array(height,width) of shrunk dimensions.
*/
function get_udims( $width, $height) {
return wp_constrain_dimensions( $width, $height, 128, 96 );
}
/**
* Convert a fraction string to a decimal.
*
* @since 2.5.0
*
* @param string $str
* @return int|float
*/
function wp_exif_frac2dec($str) {
@list( $n, $d ) = explode( '/', $str );
if ( !empty($d) )
return $n / $d;
return $str;
}
/**
* Convert the exif date format to a unix timestamp.
*
* @since 2.5.0
*
* @param string $str
* @return int
*/
function wp_exif_date2ts($str) {
@list( $date, $time ) = explode( ' ', trim($str) );
@list( $y, $m, $d ) = explode( ':', $date );
return strtotime( "{$y}-{$m}-{$d} {$time}" );
}
/**
* Get extended image metadata, exif or iptc as available.
*
* Retrieves the EXIF metadata aperture, credit, camera, caption, copyright, iso
* created_timestamp, focal_length, shutter_speed, and title.
*
* The IPTC metadata that is retrieved is APP13, credit, byline, created date
* and time, caption, copyright, and title. Also includes FNumber, Model,
* DateTimeDigitized, FocalLength, ISOSpeedRatings, and ExposureTime.
*
* @todo Try other exif libraries if available.
* @since 2.5.0
*
* @param string $file
* @return bool|array False on failure. Image metadata array on success.
*/
function wp_read_image_metadata( $file ) {
if ( ! file_exists( $file ) )
return false;
list( , , $sourceImageType ) = getimagesize( $file );
// exif contains a bunch of data we'll probably never need formatted in ways
// that are difficult to use. We'll normalize it and just extract the fields
// that are likely to be useful. Fractions and numbers are converted to
// floats, dates to unix timestamps, and everything else to strings.
$meta = array(
'aperture' => 0,
'credit' => '',
'camera' => '',
'caption' => '',
'created_timestamp' => 0,
'copyright' => '',
'focal_length' => 0,
'iso' => 0,
'shutter_speed' => 0,
'title' => '',
);
// read iptc first, since it might contain data not available in exif such
// as caption, description etc
if ( is_callable( 'iptcparse' ) ) {
getimagesize( $file, $info );
if ( ! empty( $info['APP13'] ) ) {
$iptc = iptcparse( $info['APP13'] );
// headline, "A brief synopsis of the caption."
if ( ! empty( $iptc['2#105'][0] ) )
$meta['title'] = utf8_encode( trim( $iptc['2#105'][0] ) );
// title, "Many use the Title field to store the filename of the image, though the field may be used in many ways."
elseif ( ! empty( $iptc['2#005'][0] ) )
$meta['title'] = utf8_encode( trim( $iptc['2#005'][0] ) );
if ( ! empty( $iptc['2#120'][0] ) ) { // description / legacy caption
$caption = utf8_encode( trim( $iptc['2#120'][0] ) );
if ( empty( $meta['title'] ) ) {
// Assume the title is stored in 2:120 if it's short.
if ( strlen( $caption ) < 80 )
$meta['title'] = $caption;
else
$meta['caption'] = $caption;
} elseif ( $caption != $meta['title'] ) {
$meta['caption'] = $caption;
}
}
if ( ! empty( $iptc['2#110'][0] ) ) // credit
$meta['credit'] = utf8_encode(trim($iptc['2#110'][0]));
elseif ( ! empty( $iptc['2#080'][0] ) ) // creator / legacy byline
$meta['credit'] = utf8_encode(trim($iptc['2#080'][0]));
if ( ! empty( $iptc['2#055'][0] ) and ! empty( $iptc['2#060'][0] ) ) // created date and time
$meta['created_timestamp'] = strtotime( $iptc['2#055'][0] . ' ' . $iptc['2#060'][0] );
if ( ! empty( $iptc['2#116'][0] ) ) // copyright
$meta['copyright'] = utf8_encode( trim( $iptc['2#116'][0] ) );
}
}
// fetch additional info from exif if available
if ( is_callable( 'exif_read_data' ) && in_array( $sourceImageType, apply_filters( 'wp_read_image_metadata_types', array( IMAGETYPE_JPEG, IMAGETYPE_TIFF_II, IMAGETYPE_TIFF_MM ) ) ) ) {
$exif = @exif_read_data( $file );
if ( !empty( $exif['Title'] ) )
$meta['title'] = utf8_encode( trim( $exif['Title'] ) );
if ( ! empty( $exif['ImageDescription'] ) ) {
if ( empty( $meta['title'] ) && strlen( $exif['ImageDescription'] ) < 80 ) {
// Assume the title is stored in ImageDescription
$meta['title'] = utf8_encode( trim( $exif['ImageDescription'] ) );
if ( ! empty( $exif['COMPUTED']['UserComment'] ) && trim( $exif['COMPUTED']['UserComment'] ) != $meta['title'] )
$meta['caption'] = utf8_encode( trim( $exif['COMPUTED']['UserComment'] ) );
} elseif ( trim( $exif['ImageDescription'] ) != $meta['title'] ) {
$meta['caption'] = utf8_encode( trim( $exif['ImageDescription'] ) );
}
} elseif ( ! empty( $exif['Comments'] ) && trim( $exif['Comments'] ) != $meta['title'] ) {
$meta['caption'] = utf8_encode( trim( $exif['Comments'] ) );
}
if ( ! empty( $exif['Artist'] ) )
$meta['credit'] = utf8_encode( trim( $exif['Artist'] ) );
elseif ( ! empty($exif['Author'] ) )
$meta['credit'] = utf8_encode( trim( $exif['Author'] ) );
if ( ! empty( $exif['Copyright'] ) )
$meta['copyright'] = utf8_encode( trim( $exif['Copyright'] ) );
if ( ! empty($exif['FNumber'] ) )
$meta['aperture'] = round( wp_exif_frac2dec( $exif['FNumber'] ), 2 );
if ( ! empty($exif['Model'] ) )
$meta['camera'] = utf8_encode( trim( $exif['Model'] ) );
if ( ! empty($exif['DateTimeDigitized'] ) )
$meta['created_timestamp'] = wp_exif_date2ts($exif['DateTimeDigitized'] );
if ( ! empty($exif['FocalLength'] ) )
$meta['focal_length'] = wp_exif_frac2dec( $exif['FocalLength'] );
if ( ! empty($exif['ISOSpeedRatings'] ) )
$meta['iso'] = utf8_encode( trim( $exif['ISOSpeedRatings'] ) );
if ( ! empty($exif['ExposureTime'] ) )
$meta['shutter_speed'] = wp_exif_frac2dec( $exif['ExposureTime'] );
}
return apply_filters( 'wp_read_image_metadata', $meta, $file, $sourceImageType );
}
/**
* Validate that file is an image.
*
* @since 2.5.0
*
* @param string $path File path to test if valid image.
* @return bool True if valid image, false if not valid image.
*/
function file_is_valid_image($path) {
$size = @getimagesize($path);
return !empty($size);
}
/**
* Validate that file is suitable for displaying within a web page.
*
* @since 2.5.0
* @uses apply_filters() Calls 'file_is_displayable_image' on $result and $path.
*
* @param string $path File path to test.
* @return bool True if suitable, false if not suitable.
*/
function file_is_displayable_image($path) {
$info = @getimagesize($path);
if ( empty($info) )
$result = false;
elseif ( !in_array($info[2], array(IMAGETYPE_GIF, IMAGETYPE_JPEG, IMAGETYPE_PNG)) ) // only gif, jpeg and png images can reliably be displayed
$result = false;
else
$result = true;
return apply_filters('file_is_displayable_image', $result, $path);
}