Adjust copyrights years
<?php
/**
* SeekQuarry/Yioop --
* Open Source Pure PHP Search Engine, Crawler, and Indexer
*
* Copyright (C) 2009 - 2018 Chris Pollett chris@pollett.org
*
* LICENSE:
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
* END LICENSE
*
* @author Chris Pollett chris@pollett.org
* @license https://www.gnu.org/licenses/ GPL3
* @link https://www.seekquarry.com/
* @copyright 2009 - 2018
* @filesource
*/
namespace seekquarry\yioop\library\processors;
use seekquarry\yioop\library\UrlParser;
/**
* Used to create crawl summary information
* for BMP and ICO files
*
* @author Chris Pollett
*/
class BmpProcessor extends ImageProcessor
{
/**
* Size in bytes of one block to read in of BMP
*/
const BLOCK_SIZE = 4096;
/**
* Size in bytes of BMP identifier and size info
*/
const BMP_ID = 10;
/**
* Size in bytes of BMP header
*/
const BMP_HEADER_LEN = 108;
/**
* Maximum pixel width or height
*/
const MAX_DIM = 1000;
/**
* Set-ups the any indexing plugins associated with this page
* processor
*
* @param array $plugins an array of indexing plugins which might
* do further processing on the data handles by this page
* processor
* @param int $max_description_len maximal length of a page summary
* @param string $summarizer_option CRAWL_CONSTANT specifying what kind
* of summarizer to use self::BASIC_SUMMARIZER,
* self::GRAPH_BASED_SUMMARIZER and self::CENTROID_SUMMARIZER
* self::CENTROID_SUMMARIZER
*/
public function __construct($plugins = [], $max_description_len = null,
$summarizer_option = self::BASIC_SUMMARIZER)
{
parent::__construct($plugins, $max_description_len, $summarizer_option);
/** Register File Types We Handle*/
self::$indexed_file_types[] = "bmp";
self::$image_types[] = "bmp";
self::$mime_processor["image/bmp"] = "BmpProcessor";
}
/**
* {@inheritDoc}
*
* @param string $page the image represented as a character string
* @param string $url the url where the image was downloaded from
* @return array summary information including a thumbnail and a
* description (where the description is just the url)
*/
public function process($page, $url)
{
if (is_string($page)) {
$image = $this->imagecreatefrombmp($page);
$thumb_string = self::createThumb($image);
$summary[self::TITLE] = "";
$summary[self::DESCRIPTION] = "Image of ".
UrlParser::getDocumentFilename($url);
$summary[self::LINKS] = [];
$summary[self::PAGE] =
"<html><body><div><img src='data:image/bmp;base64," .
base64_encode($page)."' alt='".$summary[self::DESCRIPTION].
"' /></div></body></html>";
$summary[self::THUMB] = 'data:image/jpeg;base64,'.
base64_encode($thumb_string);
}
return $summary;
}
/**
* Reads in a 32 / 24bit non-palette bmp files from provided filename
* and returns a php image object corresponding to it. This is a crude
* variation of code from imagecreatewbmp function documentation at php.net
*
* @param string $bmp_string string with the contents of a bmp file
*/
public function imagecreatefrombmp($bmp_string)
{
$temp = unpack("H*", $bmp_string);
$hex = $temp[1];
$header = substr($hex, 0, self::BMP_HEADER_LEN);
$can_understand_flag = substr($header, 0, 4) == "424d";
// get parameters of image from header bytes
if ($can_understand_flag) {
$header_parts = str_split($header, 2);
$width = hexdec($header_parts[19] . $header_parts[18]);
$height = hexdec($header_parts[23] . $header_parts[22]);
$bits_per_pixel = hexdec($header_parts[29] . $header_parts[28]);
$can_understand_flag = (($bits_per_pixel == 24) ||
($bits_per_pixel == 32)) && ($width <
self::MAX_DIM && $height < self::MAX_DIM );
unset($header_parts);
}
$x = 0;
$y = 1;
/* We're going to manually write pixel info into the following
image object
*/
$image = imagecreatetruecolor($width, $height);
if (!$can_understand_flag) {
return $image;
}
// Grab the body from the image
$body = substr($hex, self::BMP_HEADER_LEN);
/*
Calculate any end-of-line padding needed
*/
$body_size = strlen($body)/2;
$header_size = ($width * $height);
// Set-up padding flag
$padding_flag = ($body_size > ($header_size * 3) + 4);
$pixel_step = ceil($bits_per_pixel >> 3);
// Write pixels
for ($i = 0; $i < $body_size; $i += $pixel_step)
{
// Calculate line-ending and padding
if ($x >= $width)
{
if ($padding_flag) {
$i += $width % 4;
}
$x = 0;
$y++;
if ($y > $height) break;
}
$i_pos = $i << 1;
if (!isset($body[$i_pos + 5])) { break; }
$r =hexdec($body[$i_pos + 4] . $body[$i_pos + 5]);
$g = hexdec($body[$i_pos + 2] . $body[$i_pos + 3]);
$b = hexdec($body[$i_pos].$body[$i_pos + 1]);
$color = imagecolorallocate($image, $r, $g, $b);
imagesetpixel($image, $x, $height - $y, $color);
$x++;
}
unset($body);
return $image;
}
}