<?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.

* @return string Thumbnail path on success, Error string on failure.

*/

function wp_create_thumbnail( $file, $max_side, $deprecated = '' ) {

$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 New filepath on success, String error message 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 $src;

$dst = 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 ) )

return $dst_file;

else

return false;

}

/**

* Generate post image 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) ) {

$full_path_file = $file;

$imagesize = getimagesize( $full_path_file );

$metadata['width'] = $imagesize[0];

$metadata['height'] = $imagesize[1];

list($uwidth, $uheight) = wp_shrink_dimensions($metadata['width'], $metadata['height']);

$metadata['hwstring_small'] = "height='$uheight' width='$uwidth'";

// Make the file path relative to the upload dir

if ( ($uploads = wp_upload_dir()) && false === $uploads['error'] ) { // Get upload directory

if ( 0 === strpos($file, $uploads['basedir']) ) {// Check that the upload base exists in the file path

$file = str_replace($uploads['basedir'], '', $file); // Remove upload dir from the file path

$file = ltrim($file, '/');

}

}

$metadata['file'] = $file;

// make thumbnails and other intermediate sizes

$sizes = array('thumbnail', 'medium', 'large');

$sizes = apply_filters('intermediate_image_sizes', $sizes);

foreach ($sizes as $size) {

$resized = image_make_intermediate_size( $full_path_file, get_option("{$size}_size_w"), get_option("{$size}_size_h"), get_option("{$size}_crop") );

if ( $resized )

$metadata['sizes'][$size] = $resized;

}

// fetch additional metadata from exif/iptc

$image_meta = wp_read_image_metadata( $full_path_file );

if ($image_meta)

$metadata['image_meta'] = $image_meta;

}

return apply_filters( 'wp_generate_attachment_metadata', $metadata );

}

/**

* Load an image from a string, if PHP supports it.

*

* @since 2.1.0

*

* @param string $file Filename of the image to load.

* @return resource The resulting image resource on success, Error string on failure.

*/

function wp_load_image( $file ) {

if ( is_numeric( $file ) )

$file = get_attached_file( $file );

if ( ! file_exists( $file ) )

return sprintf(__("File '%s' doesn't exist?"), $file);

if ( ! function_exists('imagecreatefromstring') )

return __('The GD image library is not installed.');

// Set artificially high because GD uses uncompressed images in memory

@ini_set('memory_limit', '256M');

$image = imagecreatefromstring( file_get_contents( $file ) );

if ( !is_resource( $image ) )

return sprintf(__("File '%s' is not an image."), $file);

return $image;

}

/**

* Calculated the new dimentions for a downsampled image.

*

* @since 2.0.0

* @see wp_shrink_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_shrink_dimensions( $width, $height );

}

/**

* Calculates the new dimentions 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

* @param int $wmax Maximum wanted width

* @param int $hmax Maximum wanted height

* @return mixed Array(height,width) of shrunk dimensions.

*/

function wp_shrink_dimensions( $width, $height, $wmax = 128, $hmax = 96 ) {

return wp_constrain_dimensions( $width, $height, $wmax, $hmax );

}

/**

* 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']);

if ( !empty($iptc['2#110'][0]) ) // credit

$meta['credit'] = utf8_encode(trim($iptc['2#110'][0]));

elseif ( !empty($iptc['2#080'][0]) ) // 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#120'][0]) ) // caption

$meta['caption'] = utf8_encode(trim($iptc['2#120'][0]));

if ( !empty($iptc['2#116'][0]) ) // copyright

$meta['copyright'] = utf8_encode(trim($iptc['2#116'][0]));

if ( !empty($iptc['2#005'][0]) ) // title

$meta['title'] = utf8_encode(trim($iptc['2#005'][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['FNumber']))

$meta['aperture'] = round( wp_exif_frac2dec( $exif['FNumber'] ), 2 );

if (!empty($exif['Model']))

$meta['camera'] = 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'] = $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);

}

?>