Add enhanced support for ASF files

git-svn-id: http://php-reader.googlecode.com/svn/trunk@108 51a70ab9-7547-0410-9469-37e369ee0574
2008-09-05 17:00:05 +00:00
parent 741de5a2ab
commit 5ab1bb40f6
29 changed files with 3370 additions and 1652 deletions
--- a/src/ASF/Object/MediaObjectIndex.php
+++ b/src/ASF/Object/MediaObjectIndex.php
@@ -0,0 +1,176 @@
+<?php
+/**
+ * PHP Reader Library
+ *
+ * Copyright (c) 2008 The PHP Reader Project Workgroup. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  - Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *  - Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *  - Neither the name of the project workgroup nor the names of its
+ *    contributors may be used to endorse or promote products derived from this
+ *    software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * @package    php-reader
+ * @subpackage ASF
+ * @copyright  Copyright (c) 2008 The PHP Reader Project Workgroup
+ * @license    http://code.google.com/p/php-reader/wiki/License New BSD License
+ * @version    $Id$
+ */
+
+/**#@+ @ignore */
+require_once("ASF/Object.php");
+/**#@-*/
+
+/**
+ * This top-level ASF object supplies media object indexing information for the
+ * streams of an ASF file. It includes stream-specific indexing information
+ * based on an adjustable index entry media object count interval. This object
+ * can be used to index all the video frames or key frames in a video stream.
+ * The index is designed to be broken into blocks to facilitate storage that is
+ * more space-efficient by using 32-bit offsets relative to a 64-bit base. That
+ * is, each index block has a full 64-bit offset in the block header that is
+ * added to the 32-bit offset found in each index entry. If a file is larger
+ * than 2^32 bytes, then multiple index blocks can be used to fully index the
+ * entire large file while still keeping index entry offsets at 32 bits.
+ * 
+ * Indices into the <i>Media Object Index Object</i> are in terms of media
+ * object numbers, with the first frame for a given stream in the ASF file
+ * corresponding to entry 0 in the <i>Media Object Index Object</i>. The
+ * corresponding <i>Offset</i> field values of the <i>Index Entry</i> are byte
+ * offsets that, when combined with the <i>Block Position</i> value of the
+ * Index Block, indicate the starting location in bytes of an ASF Data Packet
+ * relative to the start of the first ASF Data Packet in the file.
+ * 
+ * Any ASF file containing a <i>Media Object Index Object</i> shall also contain
+ * a <i>Media Object Index Parameters Object</i> in its
+ * {@link ASF_Object_Header ASF Header}.
+ *
+ * @package    php-reader
+ * @subpackage ASF
+ * @author     Sven Vollbehr <svollbehr@gmail.com>
+ * @copyright  Copyright (c) 2008 The PHP Reader Project Workgroup
+ * @license    http://code.google.com/p/php-reader/wiki/License New BSD License
+ * @version    $Rev$
+ */
+final class ASF_Object_MediaObjectIndex extends ASF_Object
+{
+  /**
+   * Indicates that the index type is Nearest Past Data Packet. The Nearest
+   * Past Data Packet indexes point to the data packet whose presentation time
+   * is closest to the index entry time.
+   */
+  const NEAREST_PAST_DATA_PACKET = 1;
+  
+  /**
+   * Indicates that the index type is Nearest Past Media. The Nearest Past
+   * Object indexes point to the closest data packet containing an entire object
+   * or first fragment of an object.
+   */
+  const NEAREST_PAST_MEDIA = 2;
+  
+  /**
+   * Indicates that the index type is Nearest Past Cleanpoint. The Nearest Past
+   * Cleanpoint indexes point to the closest data packet containing an entire
+   * object (or first fragment of an object) that has the Cleanpoint Flag set.
+   * 
+   * Nearest Past Cleanpoint is the most common type of index.
+   */
+  const NEAREST_PAST_CLEANPOINT = 3;
+  
+  /** @var integer */
+  private $_indexEntryCountInterval;
+
+  /** @var Array */
+  private $_indexSpecifiers = array();
+
+  /** @var Array */
+  private $_indexBlocks = array();
+  
+  /**
+   * Constructs the class with given parameters and reads object related data
+   * from the ASF file.
+   *
+   * @param Reader $reader  The reader object.
+   * @param Array  $options The options array.
+   */
+  public function __construct($reader, &$options = array())
+  {
+    parent::__construct($reader, $options);
+    
+    $this->_indexEntryCountInterval = $this->_reader->readUInt32LE();
+    $indexSpecifiersCount = $this->_reader->readUInt16LE();
+    $indexBlocksCount = $this->_reader->readUInt32LE();
+    for ($i = 0; $i < $indexSpecifiersCount; $i++)
+      $this->_indexSpecifiers[] = array
+        ("streamNumber" => $this->_reader->readUInt16LE(),
+         "indexType" => $this->_reader->readUInt16LE());
+    for ($i = 0; $i < $indexBlocksCount; $i++) {
+      $indexEntryCount = $this->_reader->readUInt32LE();
+      $blockPositions = array();
+      for ($i = 0; $i < $indexSpecifiersCount; $i++)
+        $blockPositions[] = $this->_reader->readInt64LE();
+      $offsets = array();
+      for ($i = 0; $i < $indexSpecifiersCount; $i++)
+        $offsets[] = $this->_reader->readUInt32LE();
+      $this->_indexBlocks[] = array
+        ("blockPositions" => $blockPositions,
+         "indexEntryOffsets" => $offsets);
+    }
+  }
+
+  /**
+   * Returns the interval between each index entry in number of media objects.
+   * 
+   * @return integer
+   */
+  public function getIndexEntryCountInterval()
+  {
+    return $this->_indexEntryCountInterval;
+  }
+  
+  /**
+   * Returns an array of index specifiers. Each entry consists of the following
+   * keys.
+   * 
+   *   o streamNumber -- Specifies the stream number that the <i>Index
+   *     Specifiers</i> refer to. Valid values are between 1 and 127.
+   * 
+   *   o indexType -- Specifies the type of index.
+   *
+   * @return Array
+   */
+  public function getIndexSpecifiers() { return $this->_indexSpecifiers; }
+  
+  /**
+   * Returns an array of index entries. Each entry consists of the following
+   * keys.
+   * 
+   *   o blockPositions -- Specifies a list of byte offsets of the beginnings of
+   *     the blocks relative to the beginning of the first Data Packet (for
+   *     example, the beginning of the Data Object + 50 bytes).
+   * 
+   *   o indexEntryOffsets -- Specifies the offset. An offset value of
+   *     0xffffffff indicates an invalid offset value.
+   *
+   * @return Array
+   */
+  public function getIndexBlocks() { return $this->_indexBlocks; }
+}