web/wp-admin/includes/image.php
branchwordpress
changeset 132 4d4862461b8d
parent 109 03b0d1493584
--- a/web/wp-admin/includes/image.php	Tue Feb 02 14:45:47 2010 +0000
+++ b/web/wp-admin/includes/image.php	Tue Feb 02 15:44:16 2010 +0000
@@ -1,330 +1,343 @@
-<?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, apply_filters( 'jpeg_quality', 90, 'wp_crop_image' ) ) )
-		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 &#8220;%s&#8221; doesn&#8217;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 &#8220;%s&#8221; 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);
-}
-
-?>
+<?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 = 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, $uheight) = wp_shrink_dimensions($metadata['width'], $metadata['height']);
+		$metadata['hwstring_small'] = "height='$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;
+		$temp_sizes = array('thumbnail', 'medium', 'large'); // Standard sizes
+		if ( isset( $_wp_additional_image_sizes ) && count( $_wp_additional_image_sizes ) )
+			$temp_sizes = array_merge( $temp_sizes, array_keys( $_wp_additional_image_sizes ) );
+
+		$temp_sizes = apply_filters( 'intermediate_image_sizes', $temp_sizes );
+
+		foreach ( $temp_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 );
+}
+
+/**
+ * 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 &#8220;%s&#8221; doesn&#8217;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 &#8220;%s&#8221; 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);
+}