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* ownCloud
*
* @author Thomas Tanghus
* @copyright 2011 Thomas Tanghus <thomas@tanghus.net>
*
* This file is licensed under the Affero General Public License version 3 or
* later.
* See the COPYING-README file.
*
*/
* Class for basic image manipulation
protected $resource = false; // tmp resource.
protected $imageType = IMAGETYPE_PNG; // Default to png if file type isn't evident.
protected $mimeType = "image/png"; // Default to png
protected $bitDepth = 24;
protected $filePath = null;
private $fileInfo;
* @var \OCP\ILogger
*/
private $logger;
/**
* Get mime type for an image file.
*
* @param string|null $filePath The path to a local image file.
* @return string The mime type if the it could be determined, otherwise an empty string.
*/
static public function getMimeTypeForFile($filePath) {
// exif_imagetype throws "read error!" if file is less than 12 byte
if ($filePath !== null && filesize($filePath) > 11) {
$imageType = exif_imagetype($filePath);
} else {
$imageType = false;
return $imageType ? image_type_to_mime_type($imageType) : '';
* @param resource|string $imageRef The path to a local file, a base64 encoded string or a resource created by
public function __construct($imageRef = null, $logger = null) {
$this->logger = $logger;
if (is_null($logger)) {
$this->logger = \OC::$server->getLogger();
}
if (!extension_loaded('gd') || !function_exists('gd_info')) {
$this->logger->error(__METHOD__ . '(): GD module not installed', array('app' => 'core'));
if (\OC_Util::fileInfoLoaded()) {
$this->fileInfo = new finfo(FILEINFO_MIME_TYPE);
}
$this->load($imageRef);
* Determine whether the object contains an image resource.
*
* @return bool
*/
public function valid() { // apparently you can't name a method 'empty'...
return is_resource($this->resource);
* Returns the MIME type of the image or an empty string if no image is loaded.
*
* @return string
*/
public function mimeType() {
return $this->valid() ? $this->mimeType : '';
* Returns the width of the image or -1 if no image is loaded.
*
* @return int
*/
public function width() {
return $this->valid() ? imagesx($this->resource) : -1;
* Returns the height of the image or -1 if no image is loaded.
*
* @return int
*/
public function height() {
return $this->valid() ? imagesy($this->resource) : -1;
* Returns the width when the image orientation is top-left.
*
* @return int
*/
public function widthTopLeft() {
$o = $this->getOrientation();
$this->logger->debug('OC_Image->widthTopLeft() Orientation: ' . $o, array('app' => 'core'));
switch ($o) {
case -1:
case 1:
case 2: // Not tested
case 3:
case 4: // Not tested
return $this->width();
case 5: // Not tested
case 6:
case 7: // Not tested
case 8:
return $this->height();
}
return $this->width();
}
/**
* Returns the height when the image orientation is top-left.
*
* @return int
*/
public function heightTopLeft() {
$o = $this->getOrientation();
$this->logger->debug('OC_Image->heightTopLeft() Orientation: ' . $o, array('app' => 'core'));
switch ($o) {
case -1:
case 1:
case 2: // Not tested
case 3:
case 4: // Not tested
return $this->height();
case 5: // Not tested
case 6:
case 7: // Not tested
case 8:
return $this->width();
}
return $this->height();
}
* Outputs the image.
public function show($mimeType = null) {
if ($mimeType === null) {
$mimeType = $this->mimeType();
}
return $this->_output(null, $mimeType);
* Saves the image.
* @param string $filePath
* @param string $mimeType
* @return bool
*/
public function save($filePath = null, $mimeType = null) {
if ($mimeType === null) {
$mimeType = $this->mimeType();
}
if ($filePath === null && $this->filePath === null) {
$this->logger->error(__METHOD__ . '(): called with no path.', array('app' => 'core'));
} elseif ($filePath === null && $this->filePath !== null) {
$filePath = $this->filePath;
return $this->_output($filePath, $mimeType);
* Outputs/saves the image.
* @param string $filePath
* @param string $mimeType
* @return bool
* @throws Exception
*/
private function _output($filePath = null, $mimeType = null) {
if ($filePath) {
if (!file_exists(dirname($filePath)))
mkdir(dirname($filePath), 0777, true);
if (!is_writable(dirname($filePath))) {
$this->logger->error(__METHOD__ . '(): Directory \'' . dirname($filePath) . '\' is not writable.', array('app' => 'core'));
return false;
} elseif (is_writable(dirname($filePath)) && file_exists($filePath) && !is_writable($filePath)) {
$this->logger->error(__METHOD__ . '(): File \'' . $filePath . '\' is not writable.', array('app' => 'core'));
if (!$this->valid()) {
return false;
}
break;
case 'image/jpeg':
break;
case 'image/png':
break;
case 'image/x-xbitmap':
break;
case 'image/bmp':
break;
default:
throw new Exception('\OC_Image::_output(): "' . $mimeType . '" is not supported when forcing a specific output format');
$retVal = imagegif($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:
if (function_exists('imagexbm')) {
$retVal = imagexbm($this->resource, $filePath);
} else {
throw new Exception('\OC_Image::_output(): imagexbm() is not supported.');
}
break;
case IMAGETYPE_WBMP:
$retVal = imagewbmp($this->resource, $filePath);
$retVal = imagebmp($this->resource, $filePath, $this->bitDepth);
$retVal = imagepng($this->resource, $filePath);
return $retVal;
* @return resource Returns the image resource in any.
*/
public function resource() {
function data() {
switch ($this->mimeType) {
case "image/png":
$res = imagepng($this->resource);
break;
case "image/jpeg":
$res = imagejpeg($this->resource);
break;
case "image/gif":
$res = imagegif($this->resource);
break;
default:
$res = imagepng($this->resource);
$this->logger->info('OC_Image->data. Could not guess mime-type, defaulting to png', array('app' => 'core'));
break;
}
$this->logger->error('OC_Image->data. Error getting image data.', array('app' => 'core'));
return ob_get_clean();
}
/**
* @return string - base64 encoded, which is suitable for embedding in a VCard.
*/
function __toString() {
return base64_encode($this->data());
/**
* (I'm open for suggestions on better method name ;)
* Get the orientation based on EXIF data.
*
* @return int The orientation or -1 if no EXIF data is available.
*/
public function getOrientation() {
if ($this->imageType !== IMAGETYPE_JPEG) {
$this->logger->debug('OC_Image->fixOrientation() Image is not a JPEG.', array('app' => 'core'));
if (!is_callable('exif_read_data')) {
$this->logger->debug('OC_Image->fixOrientation() Exif module not enabled.', array('app' => 'core'));
if (!$this->valid()) {
$this->logger->debug('OC_Image->fixOrientation() No image loaded.', array('app' => 'core'));
}
if (is_null($this->filePath) || !is_readable($this->filePath)) {
$this->logger->debug('OC_Image->fixOrientation() No readable file path set.', array('app' => 'core'));
}
$exif = @exif_read_data($this->filePath, 'IFD0');
}
}
return $exif['Orientation'];
}
/**
* (I'm open for suggestions on better method name ;)
* Fixes orientation based on EXIF data.
*
* @return bool.
*/
public function fixOrientation() {
$this->logger->debug('OC_Image->fixOrientation() Orientation: ' . $o, array('app' => 'core'));
$rotate = 0;
case -1:
return false; //Nothing to fix
case 1:
$rotate = 0;
break;
$rotate = 0;
break;
case 3:
$rotate = 180;
break;
$rotate = 180;
break;
$rotate = 90;
break;
case 6:
$rotate = 270;
break;
$rotate = 270;
break;
case 8:
break;
}
if($flip) {
imageflip($this->resource, IMG_FLIP_HORIZONTAL);
}
$res = imagerotate($this->resource, $rotate, 0);
if ($res) {
if (imagealphablending($res, true)) {
if (imagesavealpha($res, true)) {
imagedestroy($this->resource);
return true;
} else {
$this->logger->debug('OC_Image->fixOrientation() Error during alpha-saving', array('app' => 'core'));
return false;
}
} else {
$this->logger->debug('OC_Image->fixOrientation() Error during alpha-blending', array('app' => 'core'));
return false;
}
} else {
$this->logger->debug('OC_Image->fixOrientation() Error during orientation fixing', array('app' => 'core'));
return false;
}
}
return false;
}
* Loads an image from a local file, a base64 encoded string or a resource created by an imagecreate* function.
* @param resource|string $imageRef The path to a local file, a base64 encoded string or a resource created by an imagecreate* function or a file resource (file handle ).
* @return resource|false An image resource or false on error
*/
public function load($imageRef) {
if (is_resource($imageRef)) {
if (get_resource_type($imageRef) == 'gd') {
$this->resource = $imageRef;
} elseif (in_array(get_resource_type($imageRef), array('file', 'stream'))) {
return $this->loadFromFileHandle($imageRef);
} elseif ($this->loadFromBase64($imageRef) !== false) {
return $this->resource;
$this->logger->debug(__METHOD__ . '(): could not load anything. Giving up!', array('app' => 'core'));
return false;
* 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 resource $handle
* @return resource|false An image resource or false on error
*/
public function loadFromFileHandle($handle) {
$contents = stream_get_contents($handle);
return $this->resource;
}
* Loads an image from a local file.
*
* @param bool|string $imagePath The path to a local file.
* @return bool|resource An image resource or false on error
*/
public function loadFromFile($imagePath = false) {
// exif_imagetype throws "read error!" if file is less than 12 byte
if (!@is_file($imagePath) || !file_exists($imagePath) || filesize($imagePath) < 12 || !is_readable($imagePath)) {

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$iType = exif_imagetype($imagePath);
switch ($iType) {
case IMAGETYPE_GIF:
if (imagetypes() & IMG_GIF) {

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$this->resource = imagecreatefromgif($imagePath);
// Preserve transparency
imagealphablending($this->resource, true);
imagesavealpha($this->resource, true);
$this->logger->debug('OC_Image->loadFromFile, GIF images not supported: ' . $imagePath, array('app' => 'core'));
}
break;
case IMAGETYPE_JPEG:
if (imagetypes() & IMG_JPG) {

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$this->resource = imagecreatefromjpeg($imagePath);
$this->logger->debug('OC_Image->loadFromFile, JPG images not supported: ' . $imagePath, array('app' => 'core'));
}
break;
case IMAGETYPE_PNG:
if (imagetypes() & IMG_PNG) {

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$this->resource = imagecreatefrompng($imagePath);
// Preserve transparency
imagealphablending($this->resource, true);
imagesavealpha($this->resource, true);
$this->logger->debug('OC_Image->loadFromFile, PNG images not supported: ' . $imagePath, array('app' => 'core'));
}
break;
case IMAGETYPE_XBM:
if (imagetypes() & IMG_XPM) {

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$this->resource = imagecreatefromxbm($imagePath);
$this->logger->debug('OC_Image->loadFromFile, XBM/XPM images not supported: ' . $imagePath, array('app' => 'core'));
}
break;
case IMAGETYPE_WBMP:
if (imagetypes() & IMG_WBMP) {

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$this->resource = imagecreatefromwbmp($imagePath);
$this->logger->debug('OC_Image->loadFromFile, WBMP images not supported: ' . $imagePath, array('app' => 'core'));
$this->resource = $this->imagecreatefrombmp($imagePath);
/*
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

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committed
$this->resource = imagecreatefromstring(\OC\Files\Filesystem::file_get_contents(\OC\Files\Filesystem::getLocalPath($imagePath)));
$iType = IMAGETYPE_PNG;
$this->logger->debug('OC_Image->loadFromFile, Default', array('app' => 'core'));
$this->imageType = $iType;
$this->mimeType = image_type_to_mime_type($iType);
$this->filePath = $imagePath;
* Loads an image from a string of data.
*
* @param string $str A string of image data as read from a file.
* @return bool|resource An image resource or false on error
*/
public function loadFromData($str) {
if ($this->fileInfo) {
$this->mimeType = $this->fileInfo->buffer($str);
}
imagealphablending($this->resource, false);
imagesavealpha($this->resource, true);
}
if (!$this->resource) {
$this->logger->debug('OC_Image->loadFromFile, could not load', array('app' => 'core'));
* Loads an image from a base64 encoded string.
*
* @param string $str A string base64 encoded string of image data.
* @return bool|resource An image resource or false on error
*/
public function loadFromBase64($str) {
return false;
}
$data = base64_decode($str);
if ($this->fileInfo) {
$this->mimeType = $this->fileInfo->buffer($data);
}
if (!$this->resource) {
$this->logger->debug('OC_Image->loadFromBase64, could not load', array('app' => 'core'));
* @link http://www.programmierer-forum.de/function-imagecreatefrombmp-laeuft-mit-allen-bitraten-t143137.htm
* @version 1.00
* @param string $fileName <p>
* @return bool|resource an image resource identifier on success, <b>FALSE</b> on errors.
private function imagecreatefrombmp($fileName) {
if (!($fh = fopen($fileName, 'rb'))) {
$this->logger->warning('imagecreatefrombmp: Can not open ' . $fileName, array('app' => 'core'));
return false;
}
// read file header
$meta = unpack('vtype/Vfilesize/Vreserved/Voffset', fread($fh, 14));
// check for bitmap
if ($meta['type'] != 19778) {
$this->logger->warning('imagecreatefrombmp: Can not open ' . $fileName . ' is not a bitmap!', array('app' => 'core'));
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->bitDepth = $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'];
$this->logger->warning('imagecreatefrombmp: Can not obtain file size of ' . $fileName . ' is not a bitmap!', array('app' => 'core'));
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']);
$this->logger->warning(
'imagecreatefrombmp: imagecreatetruecolor failed for file "' . $fileName . '" with dimensions ' . $meta['width'] . 'x' . $meta['height'],
array('app' => 'core'));
return false;
$data = fread($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))) {
$this->logger->warning($error, array('app' => 'core'));
return $im;
}
$color = unpack('V', $part . $vide);
break;
case 16:
if (!($part = substr($data, $p, 2))) {
$this->logger->warning($error, array('app' => 'core'));
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));
break;
case 4:
$color = unpack('n', $vide . substr($data, floor($p), 1));
$color[1] = ($p * 2) % 2 == 0 ? $color[1] >> 4 : $color[1] & 0x0F;
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
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;
}
$this->logger->warning('imagecreatefrombmp: ' . $fileName . ' has ' . $meta['bits'] . ' bits and this is not supported!', array('app' => 'core'));
return false;
}
imagesetpixel($im, $x, $y, $color[1]);
$x++;
$p += $meta['bytes'];
}
$y--;
$p += $meta['decal'];
}
fclose($fh);
return $im;
}
* Resizes the image preserving ratio.
*
* @param integer $maxSize The maximum size of either the width or height.
* @return bool
*/
public function resize($maxSize) {
if (!$this->valid()) {
$this->logger->error(__METHOD__ . '(): No image loaded', array('app' => 'core'));
$widthOrig = imageSX($this->resource);
$heightOrig = imageSY($this->resource);
$ratioOrig = $widthOrig / $heightOrig;
if ($ratioOrig > 1) {
$newWidth = $maxSize;
$newHeight = $maxSize;
$this->preciseResize(round($newWidth), round($newHeight));
/**
* @param int $width
* @param int $height
* @return bool
*/
public function preciseResize($width, $height) {
if (!$this->valid()) {
$this->logger->error(__METHOD__ . '(): No image loaded', array('app' => 'core'));
$widthOrig = imageSX($this->resource);
$heightOrig = imageSY($this->resource);
$process = imagecreatetruecolor($width, $height);
if ($process == false) {
$this->logger->error(__METHOD__ . '(): Error creating true color image', array('app' => 'core'));
// preserve transparency
if ($this->imageType == IMAGETYPE_GIF or $this->imageType == IMAGETYPE_PNG) {
imagecolortransparent($process, imagecolorallocatealpha($process, 0, 0, 0, 127));
imagealphablending($process, false);
imagesavealpha($process, true);
}
imagecopyresampled($process, $this->resource, 0, 0, 0, 0, $width, $height, $widthOrig, $heightOrig);
$this->logger->error(__METHOD__ . '(): Error re-sampling process image', array('app' => 'core'));
imagedestroy($process);
return false;
}
imagedestroy($this->resource);
$this->resource = $process;
return true;
}
* Crops the image to the middle square. If the image is already square it just returns.
*
* @param int $size maximum size for the result (optional)
* @return bool for success or failure
*/
public function centerCrop($size = 0) {
if (!$this->valid()) {
$this->logger->error('OC_Image->centerCrop, No image loaded', array('app' => 'core'));
$widthOrig = imageSX($this->resource);
$heightOrig = imageSY($this->resource);
if ($widthOrig === $heightOrig and $size == 0) {
$width = $height = min($widthOrig, $heightOrig);
if ($ratioOrig > 1) {
if ($size > 0) {
$targetWidth = $size;
$targetHeight = $size;
} else {
$targetWidth = $width;
$targetHeight = $height;
}
$process = imagecreatetruecolor($targetWidth, $targetHeight);
$this->logger->error('OC_Image->centerCrop, Error creating true color image', array('app' => 'core'));
// preserve transparency
if ($this->imageType == IMAGETYPE_GIF or $this->imageType == IMAGETYPE_PNG) {
imagecolortransparent($process, imagecolorallocatealpha($process, 0, 0, 0, 127));
imagealphablending($process, false);
imagesavealpha($process, true);
}
imagecopyresampled($process, $this->resource, 0, 0, $x, $y, $targetWidth, $targetHeight, $width, $height);
$this->logger->error('OC_Image->centerCrop, Error re-sampling process image ' . $width . 'x' . $height, array('app' => 'core'));
* Crops the image from point $x$y with dimension $wx$h.
*
* @param int $x Horizontal position
* @param int $y Vertical position
* @param int $w Width
* @param int $h Height
* @return bool for success or failure
*/
if (!$this->valid()) {
$this->logger->error(__METHOD__ . '(): No image loaded', array('app' => 'core'));
return false;
}
$process = imagecreatetruecolor($w, $h);
if ($process == false) {
$this->logger->error(__METHOD__ . '(): Error creating true color image', array('app' => 'core'));
if ($this->imageType == IMAGETYPE_GIF or $this->imageType == IMAGETYPE_PNG) {
imagecolortransparent($process, imagecolorallocatealpha($process, 0, 0, 0, 127));
imagealphablending($process, false);
imagesavealpha($process, true);
}
imagecopyresampled($process, $this->resource, 0, 0, $x, $y, $w, $h, $w, $h);
$this->logger->error(__METHOD__ . '(): Error re-sampling process image ' . $w . 'x' . $h, array('app' => 'core'));
* Resizes the image to fit within a boundary while preserving ratio.
*
* @param integer $maxWidth
* @param integer $maxHeight
*/
public function fitIn($maxWidth, $maxHeight) {
if (!$this->valid()) {
$this->logger->error(__METHOD__ . '(): No image loaded', array('app' => 'core'));
$widthOrig = imageSX($this->resource);
$heightOrig = imageSY($this->resource);
$ratio = $widthOrig / $heightOrig;
$newWidth = min($maxWidth, $ratio * $maxHeight);
$newHeight = min($maxHeight, $maxWidth / $ratio);
$this->preciseResize(round($newWidth), round($newHeight));
return true;
}
imagedestroy($this->resource);
}
$this->destroy();
/**
* 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 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;
$bit = 24;
}
$bits = pow(2, $bit);
imagetruecolortopalette($im, true, $bits);
$width = imagesx($im);
$height = imagesy($im);
$colorsNum = imagecolorstotal($im);
$rgbQuad = '';
for ($i = 0; $i < $colorsNum; $i++) {
$colors = imagecolorsforindex($im, $i);
$rgbQuad .= chr($colors['blue']) . chr($colors['green']) . chr($colors['red']) . "\0";
$bmpData = '';
if ($compression == 0 || $bit < 8) {
$compression = 0;
$extra = '';
$padding = 4 - ceil($width / (8 / $bit)) % 4;
if ($padding % 4 != 0) {
$extra = str_repeat("\0", $padding);
}