GC_Image_Editor
最后更新于：2021-11-25 20:36:21
GC_Image_EditorBase image editor class from which implementations extend
源文件
文件: gc-includes/class-gc-image-editor.php
abstract class GC_Image_Editor {
protected $file = null;
protected $size = null;
protected $mime_type = null;
protected $output_mime_type = null;
protected $default_mime_type = 'image/jpeg';
protected $quality = false;
// Deprecated since 5.8.1. See get_default_quality() below.
protected $default_quality = 82;
/**
* Each instance handles a single file.
*
* @param string $file Path to the file to load.
*/
public function __construct( $file ) {
$this->file = $file;
}
/**
* Checks to see if current environment supports the editor chosen.
* Must be overridden in a subclass.
*
* @since 3.5.0
*
* @abstract
*
* @param array $args
* @return bool
*/
public static function test( $args = array() ) {
return false;
}
/**
* Checks to see if editor supports the mime-type specified.
* Must be overridden in a subclass.
*
* @since 3.5.0
*
* @abstract
*
* @param string $mime_type
* @return bool
*/
public static function supports_mime_type( $mime_type ) {
return false;
}
/**
* Loads image from $this->file into editor.
*
* @since 3.5.0
* @abstract
*
* @return true|GC_Error True if loaded; GC_Error on failure.
*/
abstract public function load();
/**
* Saves current image to file.
*
* @since 3.5.0
* @abstract
*
* @param string $destfilename
* @param string $mime_type
* @return array|GC_Error {'path'=>string, 'file'=>string, 'width'=>int, 'height'=>int, 'mime-type'=>string}
*/
abstract public function save( $destfilename = null, $mime_type = null );
/**
* Resizes current image.
*
* At minimum, either a height or width must be provided.
* If one of the two is set to null, the resize will
* maintain aspect ratio according to the provided dimension.
*
* @since 3.5.0
* @abstract
*
* @param int|null $max_w Image width.
* @param int|null $max_h Image height.
* @param bool $crop
* @return true|GC_Error
*/
abstract public function resize( $max_w, $max_h, $crop = false );
/**
* Resize multiple images from a single source.
*
* @since 3.5.0
* @abstract
*
* @param array $sizes {
* An array of image size arrays. Default sizes are 'small', 'medium', 'large'.
*
* @type array $size {
* @type int $width Image width.
* @type int $height Image height.
* @type bool $crop Optional. Whether to crop the image. Default false.
* }
* }
* @return array An array of resized images metadata by size.
*/
abstract public function multi_resize( $sizes );
/**
* Crops Image.
*
* @since 3.5.0
* @abstract
*
* @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 Optional. The destination width.
* @param int $dst_h Optional. The destination height.
* @param bool $src_abs Optional. If the source crop points are absolute.
* @return true|GC_Error
*/
abstract public function crop( $src_x, $src_y, $src_w, $src_h, $dst_w = null, $dst_h = null, $src_abs = false );
/**
* Rotates current image counter-clockwise by $angle.
*
* @since 3.5.0
* @abstract
*
* @param float $angle
* @return true|GC_Error
*/
abstract public function rotate( $angle );
/**
* Flips current image.
*
* @since 3.5.0
* @abstract
*
* @param bool $horz Flip along Horizontal Axis
* @param bool $vert Flip along Vertical Axis
* @return true|GC_Error
*/
abstract public function flip( $horz, $vert );
/**
* Streams current image to browser.
*
* @since 3.5.0
* @abstract
*
* @param string $mime_type The mime type of the image.
* @return true|GC_Error True on success, GC_Error object on failure.
*/
abstract public function stream( $mime_type = null );
/**
* Gets dimensions of image.
*
* @since 3.5.0
*
* @return array {
* Dimensions of the image.
*
* @type int $width The image width.
* @type int $height The image height.
* }
*/
public function get_size() {
return $this->size;
}
/**
* Sets current image size.
*
* @since 3.5.0
*
* @param int $width
* @param int $height
* @return true
*/
protected function update_size( $width = null, $height = null ) {
$this->size = array(
'width' => (int) $width,
'height' => (int) $height,
);
return true;
}
/**
* Gets the Image Compression quality on a 1-100% scale.
*
* @since 4.0.0
*
* @return int Compression Quality. Range: [1,100]
*/
public function get_quality() {
if ( ! $this->quality ) {
$this->set_quality();
}
return $this->quality;
}
/**
* Sets Image Compression quality on a 1-100% scale.
*
* @since 3.5.0
*
* @param int $quality Compression Quality. Range: [1,100]
* @return true|GC_Error True if set successfully; GC_Error on failure.
*/
public function set_quality( $quality = null ) {
// Use the output mime type if present. If not, fall back to the input/initial mime type.
$mime_type = ! empty( $this->output_mime_type ) ? $this->output_mime_type : $this->mime_type;
// Get the default quality setting for the mime type.
$default_quality = $this->get_default_quality( $mime_type );
if ( null === $quality ) {
/**
* Filters the default image compression quality setting.
*
* Applies only during initial editor instantiation, or when set_quality() is run
* manually without the `$quality` argument.
*
* The GC_Image_Editor::set_quality() method has priority over the filter.
*
* @since 3.5.0
*
* @param int $quality Quality level between 1 (low) and 100 (high).
* @param string $mime_type Image mime type.
*/
$quality = apply_filters( 'gc_editor_set_quality', $default_quality, $mime_type );
if ( 'image/jpeg' === $mime_type ) {
/**
* Filters the JPEG compression quality for backward-compatibility.
*
* Applies only during initial editor instantiation, or when set_quality() is run
* manually without the `$quality` argument.
*
* The GC_Image_Editor::set_quality() method has priority over the filter.
*
* The filter is evaluated under two contexts: 'image_resize', and 'edit_image',
* (when a JPEG image is saved to file).
*
* @since 2.5.0
*
* @param int $quality Quality level between 0 (low) and 100 (high) of the JPEG.
* @param string $context Context of the filter.
*/
$quality = apply_filters( 'jpeg_quality', $quality, 'image_resize' );
}
if ( $quality < 0 || $quality > 100 ) {
$quality = $default_quality;
}
}
// Allow 0, but squash to 1 due to identical images in GD, and for backward compatibility.
if ( 0 === $quality ) {
$quality = 1;
}
if ( ( $quality >= 1 ) && ( $quality <= 100 ) ) {
$this->quality = $quality;
return true;
} else {
return new GC_Error( 'invalid_image_quality', __( 'Attempted to set image quality outside of the range [1,100].' ) );
}
}
/**
* 响应s the default compression quality setting for the mime type.
*
* @since 5.8.1
*
* @param string $mime_type
* @return int The default quality setting for the mime type.
*/
protected function get_default_quality( $mime_type ) {
switch ( $mime_type ) {
case 'image/webp':
$quality = 86;
break;
case 'image/jpeg':
default:
$quality = $this->default_quality;
}
return $quality;
}
/**
* 响应s preferred mime-type and extension based on provided
* file's extension and mime, or current file's extension and mime.
*
* Will default to $this->default_mime_type if requested is not supported.
*
* Provides corrected filename only if filename is provided.
*
* @since 3.5.0
*
* @param string $filename
* @param string $mime_type
* @return array { filename|null, extension, mime-type }
*/
protected function get_output_format( $filename = null, $mime_type = null ) {
$new_ext = null;
// By default, assume specified type takes priority.
if ( $mime_type ) {
$new_ext = $this->get_extension( $mime_type );
}
if ( $filename ) {
$file_ext = strtolower( pathinfo( $filename, PATHINFO_EXTENSION ) );
$file_mime = $this->get_mime_type( $file_ext );
} else {
// If no file specified, grab editor's current extension and mime-type.
$file_ext = strtolower( pathinfo( $this->file, PATHINFO_EXTENSION ) );
$file_mime = $this->mime_type;
}
// Check to see if specified mime-type is the same as type implied by
// file extension. If so, prefer extension from file.
if ( ! $mime_type || ( $file_mime == $mime_type ) ) {
$mime_type = $file_mime;
$new_ext = $file_ext;
}
/**
* Filters the image editor output format mapping.
*
* Enables filtering the mime type used to save images. By default,
* the mapping array is empty, so the mime type matches the source image.
*
* @see GC_Image_Editor::get_output_format()
*
* @since 5.8.0
*
* @param string[] $output_format {
* An array of mime type mappings. Maps a source mime type to a new
* destination mime type. Default empty array.
*
* @type string ...$0 The new mime type.
* }
* @param string $filename Path to the image.
* @param string $mime_type The source image mime type.
* }
*/
$output_format = apply_filters( 'image_editor_output_format', array(), $filename, $mime_type );
if ( isset( $output_format[ $mime_type ] )
&& $this->supports_mime_type( $output_format[ $mime_type ] )
) {
$mime_type = $output_format[ $mime_type ];
$new_ext = $this->get_extension( $mime_type );
}
// Double-check that the mime-type selected is supported by the editor.
// If not, choose a default instead.
if ( ! $this->supports_mime_type( $mime_type ) ) {
/**
* Filters default mime type prior to getting the file extension.
*
* @see gc_get_mime_types()
*
* @since 3.5.0
*
* @param string $mime_type Mime type string.
*/
$mime_type = apply_filters( 'image_editor_default_mime_type', $this->default_mime_type );
$new_ext = $this->get_extension( $mime_type );
}
// Ensure both $filename and $new_ext are not empty.
// $this->get_extension() returns false on error which would effectively remove the extension
// from $filename. That shouldn't happen, files without extensions are not supported.
if ( $filename && $new_ext ) {
$dir = pathinfo( $filename, PATHINFO_DIRNAME );
$ext = pathinfo( $filename, PATHINFO_EXTENSION );
$filename = trailingslashit( $dir ) . gc_basename( $filename, ".$ext" ) . ".{$new_ext}";
}
if ( $mime_type && ( $mime_type !== $this->mime_type ) ) {
// The image will be converted when saving. Set the quality for the new mime-type if not already set.
if ( $mime_type !== $this->output_mime_type ) {
$this->output_mime_type = $mime_type;
$this->set_quality();
}
} elseif ( ! empty( $this->output_mime_type ) ) {
// Reset output_mime_type and quality.
$this->output_mime_type = null;
$this->set_quality();
}
return array( $filename, $new_ext, $mime_type );
}
/**
* Builds an output filename based on current file, and adding proper suffix
*
* @since 3.5.0
*
* @param string $suffix
* @param string $dest_path
* @param string $extension
* @return string filename
*/
public function generate_filename( $suffix = null, $dest_path = null, $extension = null ) {
// $suffix will be appended to the destination filename, just before the extension.
if ( ! $suffix ) {
$suffix = $this->get_suffix();
}
$dir = pathinfo( $this->file, PATHINFO_DIRNAME );
$ext = pathinfo( $this->file, PATHINFO_EXTENSION );
$name = gc_basename( $this->file, ".$ext" );
$new_ext = strtolower( $extension ? $extension : $ext );
if ( ! is_null( $dest_path ) ) {
if ( ! gc_is_stream( $dest_path ) ) {
$_dest_path = realpath( $dest_path );
if ( $_dest_path ) {
$dir = $_dest_path;
}
} else {
$dir = $dest_path;
}
}
return trailingslashit( $dir ) . "{$name}-{$suffix}.{$new_ext}";
}
/**
* Builds and returns proper suffix for file based on height and width.
*
* @since 3.5.0
*
* @return string|false suffix
*/
public function get_suffix() {
if ( ! $this->get_size() ) {
return false;
}
return "{$this->size['width']}x{$this->size['height']}";
}
/**
* Check if a JPEG image has EXIF Orientation tag and rotate it if needed.
*
* @since 5.3.0
*
* @return bool|GC_Error True if the image was rotated. False if not rotated (no EXIF data or the image doesn't need to be rotated).
* GC_Error if error while rotating.
*/
public function maybe_exif_rotate() {
$orientation = null;
if ( is_callable( 'exif_read_data' ) && 'image/jpeg' === $this->mime_type ) {
$exif_data = @exif_read_data( $this->file );
if ( ! empty( $exif_data['Orientation'] ) ) {
$orientation = (int) $exif_data['Orientation'];
}
}
/**
* Filters the `$orientation` value to correct it before rotating or to prevemnt rotating the image.
*
* @since 5.3.0
*
* @param int $orientation EXIF Orientation value as retrieved from the image file.
* @param string $file Path to the image file.
*/
$orientation = apply_filters( 'gc_image_maybe_exif_rotate', $orientation, $this->file );
if ( ! $orientation || 1 === $orientation ) {
return false;
}
switch ( $orientation ) {
case 2:
// Flip horizontally.
$result = $this->flip( true, false );
break;
case 3:
// Rotate 180 degrees or flip horizontally and vertically.
// Flipping seems faster and uses less resources.
$result = $this->flip( true, true );
break;
case 4:
// Flip vertically.
$result = $this->flip( false, true );
break;
case 5:
// Rotate 90 degrees counter-clockwise and flip vertically.
$result = $this->rotate( 90 );
if ( ! is_gc_error( $result ) ) {
$result = $this->flip( false, true );
}
break;
case 6:
// Rotate 90 degrees clockwise (270 counter-clockwise).
$result = $this->rotate( 270 );
break;
case 7:
// Rotate 90 degrees counter-clockwise and flip horizontally.
$result = $this->rotate( 90 );
if ( ! is_gc_error( $result ) ) {
$result = $this->flip( true, false );
}
break;
case 8:
// Rotate 90 degrees counter-clockwise.
$result = $this->rotate( 90 );
break;
}
return $result;
}
/**
* Either calls editor's save function or handles file as a stream.
*
* @since 3.5.0
*
* @param string|stream $filename
* @param callable $function
* @param array $arguments
* @return bool
*/
protected function make_image( $filename, $function, $arguments ) {
$stream = gc_is_stream( $filename );
if ( $stream ) {
ob_start();
} else {
// The directory containing the original file may no longer exist when using a replication plugin.
gc_mkdir_p( dirname( $filename ) );
}
$result = call_user_func_array( $function, $arguments );
if ( $result && $stream ) {
$contents = ob_get_contents();
$fp = fopen( $filename, 'w' );
if ( ! $fp ) {
ob_end_clean();
return false;
}
fwrite( $fp, $contents );
fclose( $fp );
}
if ( $stream ) {
ob_end_clean();
}
return $result;
}
/**
* 响应s first matched mime-type from extension,
* as mapped from gc_get_mime_types()
*
* @since 3.5.0
*
* @param string $extension
* @return string|false
*/
protected static function get_mime_type( $extension = null ) {
if ( ! $extension ) {
return false;
}
$mime_types = gc_get_mime_types();
$extensions = array_keys( $mime_types );
foreach ( $extensions as $_extension ) {
if ( preg_match( "/{$extension}/i", $_extension ) ) {
return $mime_types[ $_extension ];
}
}
return false;
}
/**
* 响应s first matched extension from Mime-type,
* as mapped from gc_get_mime_types()
*
* @since 3.5.0
*
* @param string $mime_type
* @return string|false
*/
protected static function get_extension( $mime_type = null ) {
if ( empty( $mime_type ) ) {
return false;
}
return gc_get_default_extension_for_mime_type( $mime_type );
}
}