PHP Icon Favicon.ico Generator

ico-gen.php

<?php
/*
Copyright 2011-2013 Chris Jean & iThemes
Licensed under GPLv2 or above
Version 1.0.2
*/
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 PHP_ICO( $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;
  }
}
// require( dirname( __FILE__ ) . '/class-php-ico.php' );
$ico_lib = new PHP_ICO( 'resources/windows/icon.ico' );
$ico_lib->save_ico( 'resources/icon.ico' );