<?php
/*
-Copyright(c)2008 Internet Archive. Software license AGPL version 3.
+Copyright(c) 2008-2010 Internet Archive. Software license AGPL version 3.
-This file is part of BookReader.
+This file is part of BookReader. The full source code can be found at GitHub:
+http://github.com/openlibrary/bookreader
+
+The canonical short name of an image type is the same as in the MIME type.
+For example both .jpeg and .jpg are considered to have type "jpeg" since
+the MIME type is "image/jpeg".
BookReader is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
along with BookReader. If not, see <http://www.gnu.org/licenses/>.
*/
-$MIMES = array('jpg' => 'image/jpeg',
- 'png' => 'image/png');
-
-$exiftool = '/petabox/sw/books/exiftool/exiftool';
-
-$zipPath = $_REQUEST['zip'];
-$file = $_REQUEST['file'];
-
-/*
- * Approach:
- *
- * Get info about requested image (input)
- * Get info about requested output format
- * Determine processing parameters
- * Process image
- * Return image data
- * Clean up temporary files
- */
-
-function getUnzipCommand($zipPath, $file)
+class BookReaderImages
{
- return 'unzip -p ' .
- escapeshellarg($zipPath) .
- ' ' . escapeshellarg($file);
-}
-
-/*
- * Get the image width, height and depth from a jp2 file in zip.
- */
-function getImageSizeAndDepth($zipPath, $file)
-{
- global $exiftool;
+ public $MIMES = array('gif' => 'image/gif',
+ 'jp2' => 'image/jp2',
+ 'jpg' => 'image/jpeg',
+ 'jpeg' => 'image/jpeg',
+ 'png' => 'image/png',
+ 'tif' => 'image/tiff',
+ 'tiff' => 'image/tiff');
+
+ public $EXTENSIONS = array('gif' => 'gif',
+ 'jp2' => 'jp2',
+ 'jpeg' => 'jpeg',
+ 'jpg' => 'jpeg',
+ 'png' => 'png',
+ 'tif' => 'tiff',
+ 'tiff' => 'tiff');
+
+ // Paths to command-line tools
+ var $exiftool = '/petabox/sw/books/exiftool/exiftool';
+ var $kduExpand = '/petabox/sw/bin/kdu_expand';
- # $$$ will exiftool work for *all* of our images?
- $cmd = getUnzipCommand($zipPath, $file)
- . ' | '. $exiftool . ' -s -s -s -ImageWidth -ImageHeight -BitsPerComponent -';
- exec($cmd, $output);
+ /*
+ * Approach:
+ *
+ * Get info about requested image (input)
+ * Get info about requested output format
+ * Determine processing parameters
+ * Process image
+ * Return image data
+ * Clean up temporary files
+ */
+
+ function serveRequest($requestEnv) {
+ // Process some of the request parameters
+ $zipPath = $requestEnv['zip'];
+ $file = $requestEnv['file'];
+ if (! $ext) {
+ $ext = $requestEnv['ext'];
+ } else {
+ // Default to jpg
+ $ext = 'jpeg';
+ }
+ if (isset($requestEnv['callback'])) {
+ // validate callback is valid JS identifier (only)
+ $callback = $requestEnv['callback'];
+ $identifierPatt = '/^[[:alpha:]$_]([[:alnum:]$_])*$/';
+ if (! preg_match($identifierPatt, $callback)) {
+ $this->BRfatal('Invalid callback');
+ }
+ } else {
+ $callback = null;
+ }
+
+ // Make sure the image stack is readable - return 403 if not
+ $this->checkPrivs($zipPath);
+
+
+ // Get the image size and depth
+ $imageInfo = $this->getImageInfo($zipPath, $file);
+
+ // Output json if requested
+ if ('json' == $ext) {
+ // $$$ we should determine the output size first based on requested scale
+ $this->outputJSON($imageInfo, $callback); // $$$ move to BookReaderRequest
+ exit;
+ }
+
+ // Unfortunately kakadu requires us to know a priori if the
+ // output file should be .ppm or .pgm. By decompressing to
+ // .bmp kakadu will write a file we can consistently turn into
+ // .pnm. Really kakadu should support .pnm as the file output
+ // extension and automatically write ppm or pgm format as
+ // appropriate.
+ $this->decompressToBmp = true; // $$$ shouldn't be necessary if we use file info to determine output format
+ if ($this->decompressToBmp) {
+ $stdoutLink = '/tmp/stdout.bmp';
+ } else {
+ $stdoutLink = '/tmp/stdout.ppm';
+ }
+
+ $fileExt = strtolower(pathinfo($file, PATHINFO_EXTENSION));
+
+ // Rotate is currently only supported for jp2 since it does not add server load
+ $allowedRotations = array("0", "90", "180", "270");
+ $rotate = $requestEnv['rotate'];
+ if ( !in_array($rotate, $allowedRotations) ) {
+ $rotate = "0";
+ }
+
+ // Image conversion options
+ $pngOptions = '';
+ $jpegOptions = '-quality 75';
+
+ // The pbmreduce reduction factor produces an image with dimension 1/n
+ // The kakadu reduction factor produceds an image with dimension 1/(2^n)
+ // $$$ handle continuous values for scale
+ if (isset($requestEnv['height'])) {
+ $ratio = floatval($requestEnv['origHeight']) / floatval($requestEnv['height']);
+ if ($ratio <= 2) {
+ $scale = 2;
+ $powReduce = 1;
+ } else if ($ratio <= 4) {
+ $scale = 4;
+ $powReduce = 2;
+ } else {
+ //$powReduce = 3; //too blurry!
+ $scale = 2;
+ $powReduce = 1;
+ }
+
+ } else {
+ // $$$ could be cleaner
+ // Provide next smaller power of two reduction
+ $scale = intval($requestEnv['scale']);
+ if (1 >= $scale) {
+ $powReduce = 0;
+ } else if (2 > $scale) {
+ $powReduce = 0;
+ } else if (4 > $scale) {
+ $powReduce = 1;
+ } else if (8 > $scale) {
+ $powReduce = 2;
+ } else if (16 > $scale) {
+ $powReduce = 3;
+ } else if (32 > $scale) {
+ $powReduce = 4;
+ } else if (64 > $scale) {
+ $powReduce = 5;
+ } else {
+ // $$$ Leaving this in as default though I'm not sure why it is...
+ $powReduce = 3;
+ }
+ $scale = pow(2, $powReduce);
+ }
+
+ // Override depending on source image format
+ // $$$ consider doing a 302 here instead, to make better use of the browser cache
+ // Limit scaling for 1-bit images. See https://bugs.edge.launchpad.net/bookreader/+bug/486011
+ if (1 == $imageInfo['bits']) {
+ if ($scale > 1) {
+ $scale /= 2;
+ $powReduce -= 1;
+
+ // Hard limit so there are some black pixels to use!
+ if ($scale > 4) {
+ $scale = 4;
+ $powReduce = 2;
+ }
+ }
+ }
+
+ if (!file_exists($stdoutLink))
+ {
+ system('ln -s /dev/stdout ' . $stdoutLink);
+ }
+
+
+ putenv('LD_LIBRARY_PATH=/petabox/sw/lib/kakadu');
+
+ $unzipCmd = $this->getUnarchiveCommand($zipPath, $file);
+
+ $decompressCmd = $this->getDecompressCmd($imageInfo['type'], $powReduce, $rotate, $scale, $stdoutLink);
+
+ // Non-integer scaling is currently disabled on the cluster
+ // if (isset($_REQUEST['height'])) {
+ // $cmd .= " | pnmscale -height {$_REQUEST['height']} ";
+ // }
+
+ switch ($ext) {
+ case 'png':
+ $compressCmd = ' | pnmtopng ' . $pngOptions;
+ break;
+
+ case 'jpeg':
+ case 'jpg':
+ default:
+ $compressCmd = ' | pnmtojpeg ' . $jpegOptions;
+ $ext = 'jpeg'; // for matching below
+ break;
+
+ }
+
+ if (($ext == $fileExt) && ($scale == 1) && ($rotate === "0")) {
+ // Just pass through original data if same format and size
+ $cmd = $unzipCmd;
+ } else {
+ $cmd = $unzipCmd . $decompressCmd . $compressCmd;
+ }
+
+ // print $cmd;
+
+ $headers = array('Content-type: '. $MIMES[$ext],
+ 'Cache-Control: max-age=15552000');
+
+ $errorMessage = '';
+ if (! $this->passthruIfSuccessful($headers, $cmd, $errorMessage)) { // $$$ move to BookReaderRequest
+ // $$$ automated reporting
+ trigger_error('BookReader Processing Error: ' . $cmd . ' -- ' . $errorMessage, E_USER_WARNING);
+
+ // Try some content-specific recovery
+ $recovered = false;
+ if ($imageInfo['type'] == 'jp2') {
+ $records = $this->getJp2Records($zipPath, $file);
+ if ($powReduce > intval($records['Clevels'])) {
+ $powReduce = $records['Clevels'];
+ $reduce = pow(2, $powReduce);
+ } else {
+ $reduce = 1;
+ $powReduce = 0;
+ }
+
+ $cmd = $unzipCmd . $this->getDecompressCmd($imageInfo['type'], $powReduce, $rotate, $scale, $stdoutLink) . $compressCmd;
+ if ($this->passthruIfSuccessful($headers, $cmd, $errorMessage)) { // $$$ move to BookReaderRequest
+ $recovered = true;
+ } else {
+ trigger_error('BookReader fallback image processing also failed: ' . $errorMessage, E_USER_WARNING);
+ }
+ }
+
+ if (! $recovered) {
+ $this->BRfatal('Problem processing image - command failed');
+ }
+ }
+
+ if (isset($tempFile)) {
+ unlink($tempFile);
+ }
+ }
- preg_match('/^(\d+)/', $output[2], $groups);
- $bits = intval($groups[1]);
+ function getUnarchiveCommand($archivePath, $file)
+ {
+ $lowerPath = strtolower($archivePath);
+ if (preg_match('/\.([^\.]+)$/', $lowerPath, $matches)) {
+ $suffix = $matches[1];
+
+ if ($suffix == 'zip') {
+ return 'unzip -p '
+ . escapeshellarg($archivePath)
+ . ' ' . escapeshellarg($file);
+ } else if ($suffix == 'tar') {
+ return ' ( 7z e -so '
+ . escapeshellarg($archivePath)
+ . ' ' . escapeshellarg($file) . ' 2>/dev/null ) ';
+ } else {
+ $this->BRfatal('Incompatible archive format');
+ }
- $retval = Array('width' => intval($output[0]), 'height' => intval($output[1]),
- 'bits' => $bits);
- return $retval;
-}
-
-// Unfortunately kakadu requires us to know a priori if the
-// output file should be .ppm or .pgm. By decompressing to
-// .bmp kakadu will write a file we can consistently turn into
-// .pnm. Really kakadu should support .pnm as the file output
-// extension and automatically write ppm or pgm format as
-// appropriate.
-$decompressToBmp = true;
-if ($decompressToBmp) {
- $stdoutLink = '/tmp/stdout.bmp';
-} else {
- $stdoutLink = '/tmp/stdout.ppm';
-}
-
-if (isset($_REQUEST['ext'])) {
- $ext = $_REQUEST['ext'];
-} else {
- // Default to jpg
- $ext = 'jpg';
-}
-
-$fileExt = strtolower(pathinfo($file, PATHINFO_EXTENSION));
-
-// Rotate is currently only supported for jp2 since it does not add server load
-$allowedRotations = array("0", "90", "180", "270");
-$rotate = $_REQUEST['rotate'];
-if ( !in_array($rotate, $allowedRotations) ) {
- $rotate = "0";
-}
-
-// Image conversion options
-$pngOptions = '';
-$jpegOptions = '-quality 75';
-
-// The pbmreduce reduction factor produces an image with dimension 1/n
-// The kakadu reduction factor produceds an image with dimension 1/(2^n)
-
-if (isset($_REQUEST['height'])) {
- $ratio = floatval($_REQUEST['origHeight']) / floatval($_REQUEST['height']);
- if ($ratio <= 2) {
- $scale = 2;
- $powReduce = 1;
- } else if ($ratio <= 4) {
- $scale = 4;
- $powReduce = 2;
- } else {
- //$powReduce = 3; //too blurry!
- $scale = 2;
- $powReduce = 1;
- }
-
-} else {
- $scale = $_REQUEST['scale'];
- if (1 >= $scale) {
- $scale = 1;
- $powReduce = 0;
- } else if (2 == $scale) {
- $powReduce = 1;
- } else if (4 == $scale) {
- $powReduce = 2;
- } else if (8 == $scale) {
- $powReduce = 3;
- } else if (16 == $scale) {
- $powReduce = 4;
- } else if (32 == $scale) {
- $powReduce = 5;
- } else {
- // $$$ Leaving this in as default though I'm not sure why it is...
- $scale = 8;
- $powReduce = 3;
+ } else {
+ $this->BRfatal('Bad image stack path');
+ }
+
+ $this->BRfatal('Bad image stack path or archive format');
+
}
-}
-
-if (!file_exists($stdoutLink))
-{
- system('ln -s /dev/stdout ' . $stdoutLink);
-}
-
-
-putenv('LD_LIBRARY_PATH=/petabox/sw/lib/kakadu');
-
-$unzipCmd = getUnzipCommand($zipPath, $file);
+
+ /*
+ * Returns the image type associated with the file extension.
+ */
+ function imageExtensionToType($extension)
+ {
-if ('jp2' == $fileExt) {
- $decompressCmd =
- " | /petabox/sw/bin/kdu_expand -no_seek -quiet -reduce $powReduce -rotate $rotate -i /dev/stdin -o " . $stdoutLink;
- if ($decompressToBmp) {
- $decompressCmd .= ' | bmptopnm ';
+ if (array_key_exists($extension, $this->EXTENSIONS)) {
+ return $this->EXTENSIONS[$extension];
+ } else {
+ $this->BRfatal('Unknown image extension');
+ }
}
-} else if ('tif' == $fileExt) {
- // We need to create a temporary file for tifftopnm since it cannot
- // work on a pipe (the file must be seekable).
- // We use the BookReaderTiff prefix to give a hint in case things don't
- // get cleaned up.
- $tempFile = tempnam("/tmp", "BookReaderTiff");
+ /*
+ * Get the image information. The returned associative array fields will
+ * vary depending on the image type. The basic keys are width, height, type
+ * and bits.
+ */
+ function getImageInfo($zipPath, $file)
+ {
+ return $this->getImageInfoFromExif($zipPath, $file); // this is fast
+
+ /*
+ $fileExt = strtolower(pathinfo($file, PATHINFO_EXTENSION));
+ $type = imageExtensionToType($fileExt);
+
+ switch ($type) {
+ case "jp2":
+ return getImageInfoFromJp2($zipPath, $file);
+
+ default:
+ return getImageInfoFromExif($zipPath, $file);
+ }
+ */
+ }
- if (1 != $scale) {
- if (onPowerNode()) {
- $pbmReduce = ' | pnmscale -reduce ' . $scale;
- } else {
- $pbmReduce = ' | pnmscale -nomix -reduce ' . $scale;
+ // Get the records of of JP2 as returned by kdu_expand
+ function getJp2Records($zipPath, $file)
+ {
+
+ $cmd = $this->getUnarchiveCommand($zipPath, $file)
+ . ' | ' . $this->kduExpand
+ . ' -no_seek -quiet -i /dev/stdin -record /dev/stdout';
+ exec($cmd, $output);
+
+ $records = Array();
+ foreach ($output as $line) {
+ $elems = explode("=", $line, 2);
+ if (1 == count($elems)) {
+ // delimiter not found
+ continue;
+ }
+ $records[$elems[0]] = $elems[1];
}
- } else {
- $pbmReduce = '';
+
+ return $records;
}
- $decompressCmd =
- ' > ' . $tempFile . ' ; tifftopnm ' . $tempFile . ' 2>/dev/null' . $pbmReduce;
-
-} else {
- BRfatal('Unknown source file extension: ' . $fileExt);
-}
+ /*
+ * Get the image width, height and depth using the EXIF information.
+ */
+ function getImageInfoFromExif($zipPath, $file)
+ {
+
+ // We look for all the possible tags of interest then act on the
+ // ones presumed present based on the file type
+ $tagsToGet = ' -ImageWidth -ImageHeight -FileType' // all formats
+ . ' -BitsPerComponent -ColorSpace' // jp2
+ . ' -BitDepth' // png
+ . ' -BitsPerSample'; // tiff
+
+ $cmd = $this->getUnarchiveCommand($zipPath, $file)
+ . ' | '. $this->exiftool . ' -S -fast' . $tagsToGet . ' -';
+ exec($cmd, $output);
+
+ $tags = Array();
+ foreach ($output as $line) {
+ $keyValue = explode(": ", $line);
+ $tags[$keyValue[0]] = $keyValue[1];
+ }
+
+ $width = intval($tags["ImageWidth"]);
+ $height = intval($tags["ImageHeight"]);
+ $type = strtolower($tags["FileType"]);
+
+ switch ($type) {
+ case "jp2":
+ $bits = intval($tags["BitsPerComponent"]);
+ break;
+ case "tiff":
+ $bits = intval($tags["BitsPerSample"]);
+ break;
+ case "jpeg":
+ $bits = 8;
+ break;
+ case "png":
+ $bits = intval($tags["BitDepth"]);
+ break;
+ default:
+ $this->BRfatal("Unsupported image type");
+ break;
+ }
-// Non-integer scaling is currently disabled on the cluster
-// if (isset($_REQUEST['height'])) {
-// $cmd .= " | pnmscale -height {$_REQUEST['height']} ";
-// }
-
-if ('jpg' == $ext) {
- $compressCmd = ' | pnmtojpeg ' . $jpegOptions;
-} else if ('png' == $ext) {
- $compressCmd = ' | pnmtopng ' . $pngOptions;
-}
-
-$cmd = $unzipCmd . $decompressCmd . $compressCmd;
-
-//print $cmd;
-
-
-header('Content-type: ' . $MIMES[$ext]);
-header('Cache-Control: max-age=15552000');
-passthru ($cmd); # cmd returns image data
-
-if (isset($tempFile)) {
- unlink($tempFile);
-}
-
-function BRFatal($string) {
- echo "alert('$string')\n";
- die(-1);
-}
-
-// Returns true if using a power node
-function onPowerNode() {
- exec("lspci | fgrep -c Realtek", $output, $return);
- if ("0" != $output[0]) {
- return true;
- } else {
- exec("egrep -q AMD /proc/cpuinfo", $output, $return);
- if ($return == 0) {
+
+ $retval = Array('width' => $width, 'height' => $height,
+ 'bits' => $bits, 'type' => $type);
+
+ return $retval;
+ }
+
+ /*
+ * Output JSON given the imageInfo associative array
+ */
+ function outputJSON($imageInfo, $callback)
+ {
+ header('Content-type: text/plain');
+ $jsonOutput = json_encode($imageInfo);
+ if ($callback) {
+ $jsonOutput = $callback . '(' . $jsonOutput . ');';
+ }
+ echo $jsonOutput;
+ }
+
+ function getDecompressCmd($imageType, $powReduce, $rotate, $scale, $stdoutLink) {
+
+ switch ($imageType) {
+ case 'jp2':
+ $decompressCmd =
+ " | " . $this->kduExpand . " -no_seek -quiet -reduce $powReduce -rotate $rotate -i /dev/stdin -o " . $stdoutLink;
+ if ($this->decompressToBmp) {
+ // We suppress output since bmptopnm always outputs on stderr
+ $decompressCmd .= ' | (bmptopnm 2>/dev/null)';
+ }
+ break;
+
+ case 'tiff':
+ // We need to create a temporary file for tifftopnm since it cannot
+ // work on a pipe (the file must be seekable).
+ // We use the BookReaderTiff prefix to give a hint in case things don't
+ // get cleaned up.
+ $tempFile = tempnam("/tmp", "BookReaderTiff");
+
+ // $$$ look at bit depth when reducing
+ $decompressCmd =
+ ' > ' . $tempFile . ' ; tifftopnm ' . $tempFile . ' 2>/dev/null' . $this->reduceCommand($scale);
+ break;
+
+ case 'jpeg':
+ $decompressCmd = ' | ( jpegtopnm 2>/dev/null ) ' . $this->reduceCommand($scale);
+ break;
+
+ case 'png':
+ $decompressCmd = ' | ( pngtopnm 2>/dev/null ) ' . $this->reduceCommand($scale);
+ break;
+
+ default:
+ $this->BRfatal('Unknown image type: ' . $imageType);
+ break;
+ }
+ return $decompressCmd;
+ }
+
+ // If the command has its initial output on stdout the headers will be emitted followed
+ // by the stdout output. If initial output is on stderr an error message will be
+ // returned.
+ //
+ // Returns:
+ // true - if command emits stdout and has zero exit code
+ // false - command has initial output on stderr or non-zero exit code
+ // &$errorMessage - error string if there was an error
+ //
+ // $$$ Tested with our command-line image processing. May be deadlocks for
+ // other cases.
+ function passthruIfSuccessful($headers, $cmd, &$errorMessage)
+ {
+ $retVal = false;
+ $errorMessage = '';
+
+ $descriptorspec = array(
+ 0 => array("pipe", "r"), // stdin is a pipe that the child will read from
+ 1 => array("pipe", "w"), // stdout is a pipe that the child will write to
+ 2 => array("pipe", "w"), // stderr is a pipe to write to
+ );
+
+ $cwd = NULL;
+ $env = NULL;
+
+ $process = proc_open($cmd, $descriptorspec, $pipes, $cwd, $env);
+
+ if (is_resource($process)) {
+ // $pipes now looks like this:
+ // 0 => writeable handle connected to child stdin
+ // 1 => readable handle connected to child stdout
+ // 2 => readable handle connected to child stderr
+
+ $stdin = $pipes[0];
+ $stdout = $pipes[1];
+ $stderr = $pipes[2];
+
+ // check whether we get input first on stdout or stderr
+ $read = array($stdout, $stderr);
+ $write = NULL;
+ $except = NULL;
+ $numChanged = stream_select($read, $write, $except, NULL); // $$$ no timeout
+ if (false === $numChanged) {
+ // select failed
+ $errorMessage = 'Select failed';
+ $retVal = false;
+ }
+ if ($read[0] == $stdout && (1 == $numChanged)) {
+ // Got output first on stdout (only)
+ // $$$ make sure we get all stdout
+ $output = fopen('php://output', 'w');
+ foreach($headers as $header) {
+ header($header);
+ }
+ stream_copy_to_stream($pipes[1], $output);
+ fclose($output); // okay since tied to special php://output
+ $retVal = true;
+ } else {
+ // Got output on stderr
+ // $$$ make sure we get all stderr
+ $errorMessage = stream_get_contents($stderr);
+ $retVal = false;
+ }
+
+ fclose($stderr);
+ fclose($stdout);
+ fclose($stdin);
+
+
+ // It is important that you close any pipes before calling
+ // proc_close in order to avoid a deadlock
+ $cmdRet = proc_close($process);
+ if (0 != $cmdRet) {
+ $retVal = false;
+ $errorMessage .= "Command failed with result code " . $cmdRet;
+ }
+ }
+ return $retVal;
+ }
+
+ function BRfatal($string) {
+ echo "alert('$string');\n";
+ die(-1);
+ }
+
+ // Returns true if using a power node
+ function onPowerNode() {
+ exec("lspci | fgrep -c Realtek", $output, $return);
+ if ("0" != $output[0]) {
return true;
+ } else {
+ exec("egrep -q AMD /proc/cpuinfo", $output, $return);
+ if ($return == 0) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ function reduceCommand($scale) {
+ if (1 != $scale) {
+ if ($this->onPowerNode()) {
+ return ' | pnmscale -reduce ' . $scale . ' 2>/dev/null ';
+ } else {
+ return ' | pnmscale -nomix -reduce ' . $scale . ' 2>/dev/null ';
+ }
+ } else {
+ return '';
+ }
+ }
+
+ function checkPrivs($filename) {
+ if (!is_readable($filename)) {
+ header('HTTP/1.1 403 Forbidden');
+ exit(0);
}
}
- return false;
}
+$bri = new BookReaderImages();
+$bri->serveRequest($_REQUEST);
?>
projects / bookreader.git / blobdiff