<?php
/*
Copyright 2011-2016 Chris Jean & iThemes
Licensed under GPLv2 or above
Version 1.0.4
*/
class PHP_ICO {
/**
* Images in the BMP format.
*
* @var array
* @access private
*/
var $_images = array();
/**
* Flag to tell if the required functions exist.
*
* @var boolean
* @access private
*/
var $_has_requirements = false;
/**
* Constructor - Create a new ICO generator.
*
* If the constructor is not passed a file, a file will need to be supplied using the {@link PHP_ICO::add_image}
* function in order to generate an ICO file.
*
* @param string $file Optional. Path to the source image file.
* @param array $sizes Optional. An array of sizes (each size is an array with a width and height) that the source image should be rendered at in the generated ICO file. If sizes are not supplied, the size of the source image will be used.
*/
function __construct( $file = false, $sizes = array() ) {
$required_functions = array(
'getimagesize',
'imagecreatefromstring',
'imagecreatetruecolor',
'imagecolortransparent',
'imagecolorallocatealpha',
'imagealphablending',
'imagesavealpha',
'imagesx',
'imagesy',
'imagecopyresampled',
);
foreach ( $required_functions as $function ) {
if ( ! function_exists( $function ) ) {
trigger_error( "The PHP_ICO class was unable to find the $function function, which is part of the GD library. Ensure that the system has the GD library installed and that PHP has access to it through a PHP interface, such as PHP's GD module. Since this function was not found, the library will be unable to create ICO files." );
return;
}
}
$this->_has_requirements = true;
if ( false != $file )
$this->add_image( $file, $sizes );
}
/**
* Add an image to the generator.
*
* This function adds a source image to the generator. It serves two main purposes: add a source image if one was
* not supplied to the constructor and to add additional source images so that different images can be supplied for
* different sized images in the resulting ICO file. For instance, a small source image can be used for the small
* resolutions while a larger source image can be used for large resolutions.
*
* @param string $file Path to the source image file.
* @param array $sizes Optional. An array of sizes (each size is an array with a width and height) that the source image should be rendered at in the generated ICO file. If sizes are not supplied, the size of the source image will be used.
* @return boolean true on success and false on failure.
*/
function add_image( $file, $sizes = array() ) {
if ( ! $this->_has_requirements )
return false;
if ( false === ( $im = $this->_load_image_file( $file ) ) )
return false;
if ( empty( $sizes ) )
$sizes = array( imagesx( $im ), imagesy( $im ) );
// If just a single size was passed, put it in array.
if ( ! is_array( $sizes[0] ) )
$sizes = array( $sizes );
foreach ( (array) $sizes as $size ) {
list( $width, $height ) = $size;
$new_im = imagecreatetruecolor( $width, $height );
imagecolortransparent( $new_im, imagecolorallocatealpha( $new_im, 0, 0, 0, 127 ) );
imagealphablending( $new_im, false );
imagesavealpha( $new_im, true );
$source_width = imagesx( $im );
$source_height = imagesy( $im );
if ( false === imagecopyresampled( $new_im, $im, 0, 0, 0, 0, $width, $height, $source_width, $source_height ) )
continue;
$this->_add_image_data( $new_im );
}
return true;
}
/**
* Write the ICO file data to a file path.
*
* @param string $file Path to save the ICO file data into.
* @return boolean true on success and false on failure.
*/
function save_ico( $file ) {
if ( ! $this->_has_requirements )
return false;
if ( false === ( $data = $this->_get_ico_data() ) )
return false;
if ( false === ( $fh = fopen( $file, 'w' ) ) )
return false;
if ( false === ( fwrite( $fh, $data ) ) ) {
fclose( $fh );
return false;
}
fclose( $fh );
return true;
}
/**
* Generate the final ICO data by creating a file header and adding the image data.
*
* @access private
*/
function _get_ico_data() {
if ( ! is_array( $this->_images ) || empty( $this->_images ) )
return false;
$data = pack( 'vvv', 0, 1, count( $this->_images ) );
$pixel_data = '';
$icon_dir_entry_size = 16;
$offset = 6 + ( $icon_dir_entry_size * count( $this->_images ) );
foreach ( $this->_images as $image ) {
$data .= pack( 'CCCCvvVV', $image['width'], $image['height'], $image['color_palette_colors'], 0, 1, $image['bits_per_pixel'], $image['size'], $offset );
$pixel_data .= $image['data'];
$offset += $image['size'];
}
$data .= $pixel_data;
unset( $pixel_data );
return $data;
}
/**
* Take a GD image resource and change it into a raw BMP format.
*
* @access private
*/
function _add_image_data( $im ) {
$width = imagesx( $im );
$height = imagesy( $im );
$pixel_data = array();
$opacity_data = array();
$current_opacity_val = 0;
for ( $y = $height - 1; $y >= 0; $y-- ) {
for ( $x = 0; $x < $width; $x++ ) {
$color = imagecolorat( $im, $x, $y );
$alpha = ( $color & 0x7F000000 ) >> 24;
$alpha = ( 1 - ( $alpha / 127 ) ) * 255;
$color &= 0xFFFFFF;
$color |= 0xFF000000 & ( $alpha << 24 );
$pixel_data[] = $color;
$opacity = ( $alpha <= 127 ) ? 1 : 0;
$current_opacity_val = ( $current_opacity_val << 1 ) | $opacity;
if ( ( ( $x + 1 ) % 32 ) == 0 ) {
$opacity_data[] = $current_opacity_val;
$current_opacity_val = 0;
}
}
if ( ( $x % 32 ) > 0 ) {
while ( ( $x++ % 32 ) > 0 )
$current_opacity_val = $current_opacity_val << 1;
$opacity_data[] = $current_opacity_val;
$current_opacity_val = 0;
}
}
$image_header_size = 40;
$color_mask_size = $width * $height * 4;
$opacity_mask_size = ( ceil( $width / 32 ) * 4 ) * $height;
$data = pack( 'VVVvvVVVVVV', 40, $width, ( $height * 2 ), 1, 32, 0, 0, 0, 0, 0, 0 );
foreach ( $pixel_data as $color )
$data .= pack( 'V', $color );
foreach ( $opacity_data as $opacity )
$data .= pack( 'N', $opacity );
$image = array(
'width' => $width,
'height' => $height,
'color_palette_colors' => 0,
'bits_per_pixel' => 32,
'size' => $image_header_size + $color_mask_size + $opacity_mask_size,
'data' => $data,
);
$this->_images[] = $image;
}
/**
* Read in the source image file and convert it into a GD image resource.
*
* @access private
*/
function _load_image_file( $file ) {
// Run a cheap check to verify that it is an image file.
if ( false === ( $size = getimagesize( $file ) ) )
return false;
if ( false === ( $file_data = file_get_contents( $file ) ) )
return false;
if ( false === ( $im = imagecreatefromstring( $file_data ) ) )
return false;
unset( $file_data );
return $im;
}
}