WP_Image_Editor::get_output_format() │ protected │ WP 3.5.0

Returns 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.

Method of the class: WP_Image_Editor{}

Return

Array. { filename|null, extension, mime-type }

Usage

// protected - for code of main (parent) or child class
$result = $this->get_output_format( $filename, $mime_type );

$filename(string)

-
Default: null

$mime_type(string)

-
Default: null

Changelog

WP_Image_Editor::get_output_format() WP Image Editor::get output format code ^{WP 6.3}

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 WP_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 wp_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 ) . wp_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 );
}