server/lib/image.php
2012-11-21 22:37:14 +01:00

948 lines
27 KiB
PHP

<?php
/**
* ownCloud
*
* @author Thomas Tanghus
* @copyright 2011 Thomas Tanghus <thomas@tanghus.net>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
* License as published by the Free Software Foundation; either
* version 3 of the License, or any later version.
*
* This library 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 AFFERO GENERAL PUBLIC LICENSE for more details.
*
* You should have received a copy of the GNU Affero General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*/
/**
* Class for basic image manipulation
*/
class OC_Image {
protected $resource = false; // tmp resource.
protected $imagetype = IMAGETYPE_PNG; // Default to png if file type isn't evident.
protected $bit_depth = 24;
protected $filepath = null;
/**
* @brief Get mime type for an image file.
* @param $filepath The path to a local image file.
* @returns string The mime type if the it could be determined, otherwise an empty string.
*/
static public function getMimeTypeForFile($filepath) {
$imagetype = exif_imagetype($filepath);
return $imagetype ? image_type_to_mime_type($imagetype) : '';
}
/**
* @brief Constructor.
* @param $imageref The path to a local file, a base64 encoded string or a resource created by an imagecreate* function.
* @returns bool False on error
*/
public function __construct($imageref = null) {
//OC_Log::write('core',__METHOD__.'(): start', OC_Log::DEBUG);
if(!extension_loaded('gd') || !function_exists('gd_info')) {
OC_Log::write('core', __METHOD__.'(): GD module not installed', OC_Log::ERROR);
return false;
}
if(!is_null($imageref)) {
$this->load($imageref);
}
}
/**
* @brief Determine whether the object contains an image resource.
* @returns bool
*/
public function valid() { // apparently you can't name a method 'empty'...
return is_resource($this->resource);
}
/**
* @brief Returns the MIME type of the image or an empty string if no image is loaded.
* @returns int
*/
public function mimeType() {
return $this->valid() ? image_type_to_mime_type($this->imagetype) : '';
}
/**
* @brief Returns the width of the image or -1 if no image is loaded.
* @returns int
*/
public function width() {
return $this->valid() ? imagesx($this->resource) : -1;
}
/**
* @brief Returns the height of the image or -1 if no image is loaded.
* @returns int
*/
public function height() {
return $this->valid() ? imagesy($this->resource) : -1;
}
/**
* @brief Returns the width when the image orientation is top-left.
* @returns int
*/
public function widthTopLeft() {
$o = $this->getOrientation();
OC_Log::write('core', 'OC_Image->widthTopLeft() Orientation: '.$o, OC_Log::DEBUG);
switch($o) {
case -1:
case 1:
case 2: // Not tested
case 3:
case 4: // Not tested
return $this->width();
break;
case 5: // Not tested
case 6:
case 7: // Not tested
case 8:
return $this->height();
break;
}
return $this->width();
}
/**
* @brief Returns the height when the image orientation is top-left.
* @returns int
*/
public function heightTopLeft() {
$o = $this->getOrientation();
OC_Log::write('core', 'OC_Image->heightTopLeft() Orientation: '.$o, OC_Log::DEBUG);
switch($o) {
case -1:
case 1:
case 2: // Not tested
case 3:
case 4: // Not tested
return $this->height();
break;
case 5: // Not tested
case 6:
case 7: // Not tested
case 8:
return $this->width();
break;
}
return $this->height();
}
/**
* @brief Outputs the image.
* @returns bool
*/
public function show() {
header('Content-Type: '.$this->mimeType());
return $this->_output();
}
/**
* @brief Saves the image.
* @returns bool
*/
public function save($filepath=null) {
if($filepath === null && $this->filepath === null) {
OC_Log::write('core', __METHOD__.'(): called with no path.', OC_Log::ERROR);
return false;
} elseif($filepath === null && $this->filepath !== null) {
$filepath = $this->filepath;
}
return $this->_output($filepath);
}
/**
* @brief Outputs/saves the image.
*/
private function _output($filepath=null) {
if($filepath) {
if (!file_exists(dirname($filepath)))
mkdir(dirname($filepath), 0777, true);
if(!is_writable(dirname($filepath))) {
OC_Log::write('core', __METHOD__.'(): Directory \''.dirname($filepath).'\' is not writable.', OC_Log::ERROR);
return false;
} elseif(is_writable(dirname($filepath)) && file_exists($filepath) && !is_writable($filepath)) {
OC_Log::write('core', __METHOD__.'(): File \''.$filepath.'\' is not writable.', OC_Log::ERROR);
return false;
}
}
if (!$this->valid()) {
return false;
}
$retval = false;
switch($this->imagetype) {
case IMAGETYPE_GIF:
$retval = imagegif($this->resource, $filepath);
break;
case IMAGETYPE_JPEG:
$retval = imagejpeg($this->resource, $filepath);
break;
case IMAGETYPE_PNG:
$retval = imagepng($this->resource, $filepath);
break;
case IMAGETYPE_XBM:
$retval = imagexbm($this->resource, $filepath);
break;
case IMAGETYPE_WBMP:
$retval = imagewbmp($this->resource, $filepath);
break;
case IMAGETYPE_BMP:
$retval = imagebmp($this->resource, $filepath, $this->bit_depth);
break;
default:
$retval = imagepng($this->resource, $filepath);
}
return $retval;
}
/**
* @brief Prints the image when called as $image().
*/
public function __invoke() {
return $this->show();
}
/**
* @returns Returns the image resource in any.
*/
public function resource() {
return $this->resource;
}
/**
* @returns Returns the raw image data.
*/
function data() {
ob_start();
$res = imagepng($this->resource);
if (!$res) {
OC_Log::write('core', 'OC_Image->data. Error getting image data.', OC_Log::ERROR);
}
return ob_get_clean();
}
/**
* @returns Returns a base64 encoded string suitable for embedding in a VCard.
*/
function __toString() {
return base64_encode($this->data());
}
/**
* (I'm open for suggestions on better method name ;)
* @brief Get the orientation based on EXIF data.
* @returns The orientation or -1 if no EXIF data is available.
*/
public function getOrientation() {
if(!is_callable('exif_read_data')) {
OC_Log::write('core', 'OC_Image->fixOrientation() Exif module not enabled.', OC_Log::DEBUG);
return -1;
}
if(!$this->valid()) {
OC_Log::write('core', 'OC_Image->fixOrientation() No image loaded.', OC_Log::DEBUG);
return -1;
}
if(is_null($this->filepath) || !is_readable($this->filepath)) {
OC_Log::write('core', 'OC_Image->fixOrientation() No readable file path set.', OC_Log::DEBUG);
return -1;
}
$exif = @exif_read_data($this->filepath, 'IFD0');
if(!$exif) {
return -1;
}
if(!isset($exif['Orientation'])) {
return -1;
}
return $exif['Orientation'];
}
/**
* (I'm open for suggestions on better method name ;)
* @brief Fixes orientation based on EXIF data.
* @returns bool.
*/
public function fixOrientation() {
$o = $this->getOrientation();
OC_Log::write('core', 'OC_Image->fixOrientation() Orientation: '.$o, OC_Log::DEBUG);
$rotate = 0;
$flip = false;
switch($o) {
case -1:
return false; //Nothing to fix
break;
case 1:
$rotate = 0;
$flip = false;
break;
case 2: // Not tested
$rotate = 0;
$flip = true;
break;
case 3:
$rotate = 180;
$flip = false;
break;
case 4: // Not tested
$rotate = 180;
$flip = true;
break;
case 5: // Not tested
$rotate = 90;
$flip = true;
break;
case 6:
//$rotate = 90;
$rotate = 270;
$flip = false;
break;
case 7: // Not tested
$rotate = 270;
$flip = true;
break;
case 8:
$rotate = 90;
$flip = false;
break;
}
if($rotate) {
$res = imagerotate($this->resource, $rotate, -1);
if($res) {
if(imagealphablending($res, true)) {
if(imagesavealpha($res, true)) {
imagedestroy($this->resource);
$this->resource = $res;
return true;
} else {
OC_Log::write('core', 'OC_Image->fixOrientation() Error during alphasaving.', OC_Log::DEBUG);
return false;
}
} else {
OC_Log::write('core', 'OC_Image->fixOrientation() Error during alphablending.', OC_Log::DEBUG);
return false;
}
} else {
OC_Log::write('core', 'OC_Image->fixOrientation() Error during oriention fixing.', OC_Log::DEBUG);
return false;
}
}
}
/**
* @brief Loads an image from a local file, a base64 encoded string or a resource created by an imagecreate* function.
* @param $imageref The path to a local file, a base64 encoded string or a resource created by an imagecreate* function or a file resource (file handle ).
* @returns An image resource or false on error
*/
public function load($imageref) {
if(is_resource($imageref)) {
if(get_resource_type($imageref) == 'gd') {
$this->resource = $imageref;
return $this->resource;
} elseif(in_array(get_resource_type($imageref), array('file', 'stream'))) {
return $this->loadFromFileHandle($imageref);
}
} elseif($this->loadFromFile($imageref) !== false) {
return $this->resource;
} elseif($this->loadFromBase64($imageref) !== false) {
return $this->resource;
} elseif($this->loadFromData($imageref) !== false) {
return $this->resource;
} else {
OC_Log::write('core', __METHOD__.'(): couldn\'t load anything. Giving up!', OC_Log::DEBUG);
return false;
}
}
/**
* @brief Loads an image from an open file handle.
* It is the responsibility of the caller to position the pointer at the correct place and to close the handle again.
* @param $handle
* @returns An image resource or false on error
*/
public function loadFromFileHandle($handle) {
OC_Log::write('core', __METHOD__.'(): Trying', OC_Log::DEBUG);
$contents = stream_get_contents($handle);
if($this->loadFromData($contents)) {
return $this->resource;
}
}
/**
* @brief Loads an image from a local file.
* @param $imageref The path to a local file.
* @returns An image resource or false on error
*/
public function loadFromFile($imagepath=false) {
if(!is_file($imagepath) || !file_exists($imagepath) || !is_readable($imagepath)) {
// Debug output disabled because this method is tried before loadFromBase64?
OC_Log::write('core', 'OC_Image->loadFromFile, couldn\'t load: '.$imagepath, OC_Log::DEBUG);
return false;
}
$itype = exif_imagetype($imagepath);
switch($itype) {
case IMAGETYPE_GIF:
if (imagetypes() & IMG_GIF) {
$this->resource = imagecreatefromgif($imagepath);
} else {
OC_Log::write('core', 'OC_Image->loadFromFile, GIF images not supported: '.$imagepath, OC_Log::DEBUG);
}
break;
case IMAGETYPE_JPEG:
if (imagetypes() & IMG_JPG) {
$this->resource = imagecreatefromjpeg($imagepath);
} else {
OC_Log::write('core', 'OC_Image->loadFromFile, JPG images not supported: '.$imagepath, OC_Log::DEBUG);
}
break;
case IMAGETYPE_PNG:
if (imagetypes() & IMG_PNG) {
$this->resource = imagecreatefrompng($imagepath);
} else {
OC_Log::write('core', 'OC_Image->loadFromFile, PNG images not supported: '.$imagepath, OC_Log::DEBUG);
}
break;
case IMAGETYPE_XBM:
if (imagetypes() & IMG_XPM) {
$this->resource = imagecreatefromxbm($imagepath);
} else {
OC_Log::write('core', 'OC_Image->loadFromFile, XBM/XPM images not supported: '.$imagepath, OC_Log::DEBUG);
}
break;
case IMAGETYPE_WBMP:
if (imagetypes() & IMG_WBMP) {
$this->resource = imagecreatefromwbmp($imagepath);
} else {
OC_Log::write('core', 'OC_Image->loadFromFile, WBMP images not supported: '.$imagepath, OC_Log::DEBUG);
}
break;
case IMAGETYPE_BMP:
$this->resource = $this->imagecreatefrombmp($imagepath);
break;
/*
case IMAGETYPE_TIFF_II: // (intel byte order)
break;
case IMAGETYPE_TIFF_MM: // (motorola byte order)
break;
case IMAGETYPE_JPC:
break;
case IMAGETYPE_JP2:
break;
case IMAGETYPE_JPX:
break;
case IMAGETYPE_JB2:
break;
case IMAGETYPE_SWC:
break;
case IMAGETYPE_IFF:
break;
case IMAGETYPE_ICO:
break;
case IMAGETYPE_SWF:
break;
case IMAGETYPE_PSD:
break;
*/
default:
// this is mostly file created from encrypted file
$this->resource = imagecreatefromstring(\OC\Files\Filesystem::file_get_contents(\OC\Files\Filesystem::getLocalPath($imagepath)));
$itype = IMAGETYPE_PNG;
OC_Log::write('core', 'OC_Image->loadFromFile, Default', OC_Log::DEBUG);
break;
}
if($this->valid()) {
$this->imagetype = $itype;
$this->filepath = $imagepath;
}
return $this->resource;
}
/**
* @brief Loads an image from a string of data.
* @param $str A string of image data as read from a file.
* @returns An image resource or false on error
*/
public function loadFromData($str) {
if(is_resource($str)) {
return false;
}
$this->resource = @imagecreatefromstring($str);
if(!$this->resource) {
OC_Log::write('core', 'OC_Image->loadFromData, couldn\'t load', OC_Log::DEBUG);
return false;
}
return $this->resource;
}
/**
* @brief Loads an image from a base64 encoded string.
* @param $str A string base64 encoded string of image data.
* @returns An image resource or false on error
*/
public function loadFromBase64($str) {
if(!is_string($str)) {
return false;
}
$data = base64_decode($str);
if($data) { // try to load from string data
$this->resource = @imagecreatefromstring($data);
if(!$this->resource) {
OC_Log::write('core', 'OC_Image->loadFromBase64, couldn\'t load', OC_Log::DEBUG);
return false;
}
return $this->resource;
} else {
return false;
}
}
/**
* Create a new image from file or URL
* @link http://www.programmierer-forum.de/function-imagecreatefrombmp-laeuft-mit-allen-bitraten-t143137.htm
* @version 1.00
* @param string $filename <p>
* Path to the BMP image.
* </p>
* @return resource an image resource identifier on success, <b>FALSE</b> on errors.
*/
private function imagecreatefrombmp($filename) {
if (!($fh = fopen($filename, 'rb'))) {
trigger_error('imagecreatefrombmp: Can not open ' . $filename, E_USER_WARNING);
return false;
}
// read file header
$meta = unpack('vtype/Vfilesize/Vreserved/Voffset', fread($fh, 14));
// check for bitmap
if ($meta['type'] != 19778) {
trigger_error('imagecreatefrombmp: ' . $filename . ' is not a bitmap!', E_USER_WARNING);
return false;
}
// read image header
$meta += unpack('Vheadersize/Vwidth/Vheight/vplanes/vbits/Vcompression/Vimagesize/Vxres/Vyres/Vcolors/Vimportant', fread($fh, 40));
// read additional 16bit header
if ($meta['bits'] == 16) {
$meta += unpack('VrMask/VgMask/VbMask', fread($fh, 12));
}
// set bytes and padding
$meta['bytes'] = $meta['bits'] / 8;
$this->bit_depth = $meta['bits']; //remember the bit depth for the imagebmp call
$meta['decal'] = 4 - (4 * (($meta['width'] * $meta['bytes'] / 4)- floor($meta['width'] * $meta['bytes'] / 4)));
if ($meta['decal'] == 4) {
$meta['decal'] = 0;
}
// obtain imagesize
if ($meta['imagesize'] < 1) {
$meta['imagesize'] = $meta['filesize'] - $meta['offset'];
// in rare cases filesize is equal to offset so we need to read physical size
if ($meta['imagesize'] < 1) {
$meta['imagesize'] = @filesize($filename) - $meta['offset'];
if ($meta['imagesize'] < 1) {
trigger_error('imagecreatefrombmp: Can not obtain filesize of ' . $filename . '!', E_USER_WARNING);
return false;
}
}
}
// calculate colors
$meta['colors'] = !$meta['colors'] ? pow(2, $meta['bits']) : $meta['colors'];
// read color palette
$palette = array();
if ($meta['bits'] < 16) {
$palette = unpack('l' . $meta['colors'], fread($fh, $meta['colors'] * 4));
// in rare cases the color value is signed
if ($palette[1] < 0) {
foreach ($palette as $i => $color) {
$palette[$i] = $color + 16777216;
}
}
}
// create gd image
$im = imagecreatetruecolor($meta['width'], $meta['height']);
$data = fread($fh, $meta['imagesize']);
$p = 0;
$vide = chr(0);
$y = $meta['height'] - 1;
$error = 'imagecreatefrombmp: ' . $filename . ' has not enough data!';
// loop through the image data beginning with the lower left corner
while ($y >= 0) {
$x = 0;
while ($x < $meta['width']) {
switch ($meta['bits']) {
case 32:
case 24:
if (!($part = substr($data, $p, 3))) {
trigger_error($error, E_USER_WARNING);
return $im;
}
$color = unpack('V', $part . $vide);
break;
case 16:
if (!($part = substr($data, $p, 2))) {
trigger_error($error, E_USER_WARNING);
return $im;
}
$color = unpack('v', $part);
$color[1] = (($color[1] & 0xf800) >> 8) * 65536 + (($color[1] & 0x07e0) >> 3) * 256 + (($color[1] & 0x001f) << 3);
break;
case 8:
$color = unpack('n', $vide . substr($data, $p, 1));
$color[1] = $palette[ $color[1] + 1 ];
break;
case 4:
$color = unpack('n', $vide . substr($data, floor($p), 1));
$color[1] = ($p * 2) % 2 == 0 ? $color[1] >> 4 : $color[1] & 0x0F;
$color[1] = $palette[ $color[1] + 1 ];
break;
case 1:
$color = unpack('n', $vide . substr($data, floor($p), 1));
switch (($p * 8) % 8) {
case 0:
$color[1] = $color[1] >> 7;
break;
case 1:
$color[1] = ($color[1] & 0x40) >> 6;
break;
case 2:
$color[1] = ($color[1] & 0x20) >> 5;
break;
case 3:
$color[1] = ($color[1] & 0x10) >> 4;
break;
case 4:
$color[1] = ($color[1] & 0x8) >> 3;
break;
case 5:
$color[1] = ($color[1] & 0x4) >> 2;
break;
case 6:
$color[1] = ($color[1] & 0x2) >> 1;
break;
case 7:
$color[1] = ($color[1] & 0x1);
break;
}
$color[1] = $palette[ $color[1] + 1 ];
break;
default:
trigger_error('imagecreatefrombmp: ' . $filename . ' has ' . $meta['bits'] . ' bits and this is not supported!', E_USER_WARNING);
return false;
}
imagesetpixel($im, $x, $y, $color[1]);
$x++;
$p += $meta['bytes'];
}
$y--;
$p += $meta['decal'];
}
fclose($fh);
return $im;
}
/**
* @brief Resizes the image preserving ratio.
* @param $maxsize The maximum size of either the width or height.
* @returns bool
*/
public function resize($maxsize) {
if(!$this->valid()) {
OC_Log::write('core', __METHOD__.'(): No image loaded', OC_Log::ERROR);
return false;
}
$width_orig=imageSX($this->resource);
$height_orig=imageSY($this->resource);
$ratio_orig = $width_orig/$height_orig;
if ($ratio_orig > 1) {
$new_height = round($maxsize/$ratio_orig);
$new_width = $maxsize;
} else {
$new_width = round($maxsize*$ratio_orig);
$new_height = $maxsize;
}
$this->preciseResize(round($new_width), round($new_height));
return true;
}
public function preciseResize($width, $height) {
if (!$this->valid()) {
OC_Log::write('core', __METHOD__.'(): No image loaded', OC_Log::ERROR);
return false;
}
$width_orig=imageSX($this->resource);
$height_orig=imageSY($this->resource);
$process = imagecreatetruecolor($width, $height);
if ($process == false) {
OC_Log::write('core', __METHOD__.'(): Error creating true color image', OC_Log::ERROR);
imagedestroy($process);
return false;
}
imagecopyresampled($process, $this->resource, 0, 0, 0, 0, $width, $height, $width_orig, $height_orig);
if ($process == false) {
OC_Log::write('core', __METHOD__.'(): Error resampling process image '.$width.'x'.$height, OC_Log::ERROR);
imagedestroy($process);
return false;
}
imagedestroy($this->resource);
$this->resource = $process;
return true;
}
/**
* @brief Crops the image to the middle square. If the image is already square it just returns.
* @param int maximum size for the result (optional)
* @returns bool for success or failure
*/
public function centerCrop($size=0) {
if(!$this->valid()) {
OC_Log::write('core', 'OC_Image->centerCrop, No image loaded', OC_Log::ERROR);
return false;
}
$width_orig=imageSX($this->resource);
$height_orig=imageSY($this->resource);
if($width_orig === $height_orig and $size==0) {
return true;
}
$ratio_orig = $width_orig/$height_orig;
$width = $height = min($width_orig, $height_orig);
if ($ratio_orig > 1) {
$x = ($width_orig/2) - ($width/2);
$y = 0;
} else {
$y = ($height_orig/2) - ($height/2);
$x = 0;
}
if($size>0) {
$targetWidth=$size;
$targetHeight=$size;
}else{
$targetWidth=$width;
$targetHeight=$height;
}
$process = imagecreatetruecolor($targetWidth, $targetHeight);
if ($process == false) {
OC_Log::write('core', 'OC_Image->centerCrop. Error creating true color image', OC_Log::ERROR);
imagedestroy($process);
return false;
}
imagecopyresampled($process, $this->resource, 0, 0, $x, $y, $targetWidth, $targetHeight, $width, $height);
if ($process == false) {
OC_Log::write('core', 'OC_Image->centerCrop. Error resampling process image '.$width.'x'.$height, OC_Log::ERROR);
imagedestroy($process);
return false;
}
imagedestroy($this->resource);
$this->resource = $process;
return true;
}
/**
* @brief Crops the image from point $x$y with dimension $wx$h.
* @param $x Horizontal position
* @param $y Vertical position
* @param $w Width
* @param $h Hight
* @returns bool for success or failure
*/
public function crop($x, $y, $w, $h) {
if(!$this->valid()) {
OC_Log::write('core', __METHOD__.'(): No image loaded', OC_Log::ERROR);
return false;
}
$process = imagecreatetruecolor($w, $h);
if ($process == false) {
OC_Log::write('core', __METHOD__.'(): Error creating true color image', OC_Log::ERROR);
imagedestroy($process);
return false;
}
imagecopyresampled($process, $this->resource, 0, 0, $x, $y, $w, $h, $w, $h);
if ($process == false) {
OC_Log::write('core', __METHOD__.'(): Error resampling process image '.$w.'x'.$h, OC_Log::ERROR);
imagedestroy($process);
return false;
}
imagedestroy($this->resource);
$this->resource = $process;
return true;
}
/**
* @brief Resizes the image to fit within a boundry while preserving ratio.
* @param $maxWidth
* @param $maxHeight
* @returns bool
*/
public function fitIn($maxWidth, $maxHeight) {
if(!$this->valid()) {
OC_Log::write('core', __METHOD__.'(): No image loaded', OC_Log::ERROR);
return false;
}
$width_orig=imageSX($this->resource);
$height_orig=imageSY($this->resource);
$ratio = $width_orig/$height_orig;
$newWidth = min($maxWidth, $ratio*$maxHeight);
$newHeight = min($maxHeight, $maxWidth/$ratio);
$this->preciseResize(round($newWidth), round($newHeight));
return true;
}
public function destroy() {
if($this->valid()) {
imagedestroy($this->resource);
}
$this->resource=null;
}
public function __destruct() {
$this->destroy();
}
}
if ( ! function_exists( 'imagebmp') ) {
/**
* Output a BMP image to either the browser or a file
* @link http://www.ugia.cn/wp-data/imagebmp.php
* @author legend <legendsky@hotmail.com>
* @link http://www.programmierer-forum.de/imagebmp-gute-funktion-gefunden-t143716.htm
* @author mgutt <marc@gutt.it>
* @version 1.00
* @param resource $image
* @param string $filename [optional] <p>The path to save the file to.</p>
* @param int $bit [optional] <p>Bit depth, (default is 24).</p>
* @param int $compression [optional]
* @return bool <b>TRUE</b> on success or <b>FALSE</b> on failure.
*/
function imagebmp($im, $filename='', $bit=24, $compression=0) {
if (!in_array($bit, array(1, 4, 8, 16, 24, 32))) {
$bit = 24;
}
else if ($bit == 32) {
$bit = 24;
}
$bits = pow(2, $bit);
imagetruecolortopalette($im, true, $bits);
$width = imagesx($im);
$height = imagesy($im);
$colors_num = imagecolorstotal($im);
$rgb_quad = '';
if ($bit <= 8) {
for ($i = 0; $i < $colors_num; $i++) {
$colors = imagecolorsforindex($im, $i);
$rgb_quad .= chr($colors['blue']) . chr($colors['green']) . chr($colors['red']) . "\0";
}
$bmp_data = '';
if ($compression == 0 || $bit < 8) {
$compression = 0;
$extra = '';
$padding = 4 - ceil($width / (8 / $bit)) % 4;
if ($padding % 4 != 0) {
$extra = str_repeat("\0", $padding);
}
for ($j = $height - 1; $j >= 0; $j --) {
$i = 0;
while ($i < $width) {
$bin = 0;
$limit = $width - $i < 8 / $bit ? (8 / $bit - $width + $i) * $bit : 0;
for ($k = 8 - $bit; $k >= $limit; $k -= $bit) {
$index = imagecolorat($im, $i, $j);
$bin |= $index << $k;
$i++;
}
$bmp_data .= chr($bin);
}
$bmp_data .= $extra;
}
}
// RLE8
else if ($compression == 1 && $bit == 8) {
for ($j = $height - 1; $j >= 0; $j--) {
$last_index = "\0";
$same_num = 0;
for ($i = 0; $i <= $width; $i++) {
$index = imagecolorat($im, $i, $j);
if ($index !== $last_index || $same_num > 255) {
if ($same_num != 0) {
$bmp_data .= chr($same_num) . chr($last_index);
}
$last_index = $index;
$same_num = 1;
}
else {
$same_num++;
}
}
$bmp_data .= "\0\0";
}
$bmp_data .= "\0\1";
}
$size_quad = strlen($rgb_quad);
$size_data = strlen($bmp_data);
}
else {
$extra = '';
$padding = 4 - ($width * ($bit / 8)) % 4;
if ($padding % 4 != 0) {
$extra = str_repeat("\0", $padding);
}
$bmp_data = '';
for ($j = $height - 1; $j >= 0; $j--) {
for ($i = 0; $i < $width; $i++) {
$index = imagecolorat($im, $i, $j);
$colors = imagecolorsforindex($im, $index);
if ($bit == 16) {
$bin = 0 << $bit;
$bin |= ($colors['red'] >> 3) << 10;
$bin |= ($colors['green'] >> 3) << 5;
$bin |= $colors['blue'] >> 3;
$bmp_data .= pack("v", $bin);
}
else {
$bmp_data .= pack("c*", $colors['blue'], $colors['green'], $colors['red']);
}
}
$bmp_data .= $extra;
}
$size_quad = 0;
$size_data = strlen($bmp_data);
$colors_num = 0;
}
$file_header = 'BM' . pack('V3', 54 + $size_quad + $size_data, 0, 54 + $size_quad);
$info_header = pack('V3v2V*', 0x28, $width, $height, 1, $bit, $compression, $size_data, 0, 0, $colors_num, 0);
if ($filename != '') {
$fp = fopen($filename, 'wb');
fwrite($fp, $file_header . $info_header . $rgb_quad . $bmp_data);
fclose($fp);
return true;
}
echo $file_header . $info_header. $rgb_quad . $bmp_data;
return true;
}
}
if ( ! function_exists( 'exif_imagetype' ) ) {
/**
* Workaround if exif_imagetype does not exist
* @link http://www.php.net/manual/en/function.exif-imagetype.php#80383
* @param string $filename
* @return string|boolean
*/
function exif_imagetype ( $filename ) {
if ( ( $info = getimagesize( $filename ) ) !== false ) {
return $info[2];
}
return false;
}
}