Small fixes, improve documentation

git-svn-id: http://php-reader.googlecode.com/svn/trunk@89 51a70ab9-7547-0410-9469-37e369ee0574

src/ISO14496.php

@@ -7,12 +7,12 @@
  * 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,
+ *   <li>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,
+ *   <li>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
+ *   <li>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.
  *
@@ -57,6 +57,149 @@ require_once("ISO14496/Box.php");
  * general.
  *
  * The ISO Base Media File Format is a base format for media file formats.
+ *
+ * 
+ * An overall view of the normal encapsulation structure is provided in the
+ * following table.
+ *
+ * The table shows those boxes that may occur at the top-level in the left-most
+ * column; indentation is used to show possible containment. Thus, for example,
+ * a {@link ISO14496_Box_TKHD Track Header Box} is found in a
+ * {@link ISO14496_Box_TRAK Track Box}, which is found in a
+ * {@link ISO14496_Box_MOOV Movie Box}. Not all boxes need be used in all files;
+ * the mandatory boxes are marked with bold typeface. See the description of the
+ * individual boxes for a discussion of what must be assumed if the optional
+ * boxes are not present.
+ *
+ * User data objects shall be placed only in {@link ISO14496_Box_MOOV Movie} or
+ * {@link ISO14496_Box_TRAK Track Boxes}, and objects using an extended type may
+ * be placed in a wide variety of containers, not just the top level.
+ *
+ * <ul>
+ * <li><b>ftyp</b> -- <i>{@link ISO14496_Box_FTYP File Type Box}</i>; file type and compatibility
+ * <li>pdin -- <i>{@link ISO14496_Box_PDIN Progressive Download Information Box}</i>
+ * <li><b>moov</b> -- <i>{@link ISO14496_Box_MOOV Movie Box}</i>; container for all the metadata
+ *   <ul>
+ *   <li><b>mvhd</b> -- <i>{@link ISO14496_Box_MVHD Movie Header Box}</i>; overall declarations
+ *   <li><b>trak</b> -- <i>{@link ISO14496_Box_TRAK Track Box}</i>; container for an individual track or stream
+ *     <ul>
+ *     <li><b>tkhd</b> -- <i>{@link ISO14496_Box_TKHD Track Header Box}</i>; overall information about the track
+ *     <li>tref -- <i>{@link ISO14496_Box_TREF Track Reference Box}</i>
+ *     <li>edts -- <i>{@link ISO14496_Box_EDTS Edit Box}</i>
+ *       <ul>
+ *       <li>elst -- <i>{@link ISO14496_Box_ELST Edit List Box}</i>
+ *       </ul>
+ *     <li><b>mdia</b> -- <i>{@link ISO14496_Box_MDIA Media Box}</i>
+ *       <ul>
+ *       <li><b>mdhd</b> -- <i>{@link ISO14496_Box_MDHD Media Header Box}</i>; overall information about the media
+ *       <li><b>hdlr</b> -- <i>{@link ISO14496_Box_HDLR Handler Reference Box}</i>; declares the media type
+ *       <li><b>minf</b> -- <i>{@link ISO14496_Box_MINF Media Information Box}</i>
+ *         <ul>
+ *         <li>vmhd -- <i>{@link ISO14496_Box_VMHD Video Media Header Box}</i>; overall information (video track only)
+ *         <li>smhd -- <i>{@link ISO14496_Box_SMHD Sound Media Header Box}</i>; overall information (sound track only)
+ *         <li>hmhd -- <i>{@link ISO14496_Box_HMHD Hint Media Header Box}</i>; overall information (hint track only)
+ *         <li>nmhd -- <i>{@link ISO14496_Box_NMHD Null Media Header Box}</i>; overall information (some tracks only)
+ *         <li><b>dinf</b> -- <i>{@link ISO14496_Box_DINF Data Information Box}</i>
+ *           <ul>
+ *           <li><b>dref</b> -- <i>{@link ISO14496_Box_DREF Data Reference Box}</i>
+ *           </ul>
+ *         <li><b>stbl</b> -- <i>{@link ISO14496_Box_STBL Sample Table Box}</i>
+ *           <ul>
+ *           <li><b>stsd</b> -- <i>{@link ISO14496_Box_STSD Sample Descriptions Box}</i>
+ *           <li><b>stts</b> -- <i>{@link ISO14496_Box_STTS Decoding Time To Sample Box}</i>
+ *           <li>ctts -- <i>{@link ISO14496_Box_CTTS Composition Time To Sample Box}</i>
+ *           <li><b>stsc</b> -- <i>{@link ISO14496_Box_STSC Sample To Chunk Box}</i>
+ *           <li>stsz -- <i>{@link ISO14496_Box_STSZ Sample Size Box}</i>
+ *           <li>stz2 -- <i>{@link ISO14496_Box_STZ2 Compact Sample Size Box}</i>
+ *           <li><b>stco</b> -- <i>{@link ISO14496_Box_STCO Chunk Offset Box}</i>; 32-bit
+ *           <li>co64 -- <i>{@link ISO14496_Box_CO64 Chunk Ooffset Box}</i>; 64-bit
+ *           <li>stss -- <i>{@link ISO14496_Box_STSS Sync Sample Table Box}</i>
+ *           <li>stsh -- <i>{@link ISO14496_Box_STSH Shadow Sync Sample Table Box}</i>
+ *           <li>padb -- <i>{@link ISO14496_Box_PADB Padding Bits Box}</i>
+ *           <li>stdp -- <i>{@link ISO14496_Box_STDP Sample Degradation Priority Box}</i>
+ *           <li>sdtp -- <i>{@link ISO14496_Box_SDTP Independent and Disposable Samples Box}</i>
+ *           <li>sbgp -- <i>{@link ISO14496_Box_SBGP Sample To Group Box}</i>
+ *           <li>sgpd -- <i>{@link ISO14496_Box_SGPD Sample Group Description}</i>
+ *           <li>subs -- <i>{@link ISO14496_Box_SUBS Sub-Sample Information Box}</i>
+ *           </ul>
+ *         </ul>
+ *       </ul>
+ *     </ul>
+ *   <li>mvex -- <i>{@link ISO14496_Box_MVEX Movie Extends Box}</i>
+ *     <ul>
+ *     <li>mehd -- <i>{@link ISO14496_Box_MEHD Movie Extends Header Box}</i>
+ *     <li><b>trex</b> -- <i>{@link ISO14496_Box_TREX Track Extends Box}</i>
+ *     </ul>
+ *   <li>ipmc -- <i>{@link ISO14496_Box_IPMC IPMP Control Box}</i>
+ *   </ul>
+ * <li>moof -- <i>{@link ISO14496_Box_MOOF Movie Fragment Box}</i>
+ *   <ul>
+ *   <li><b>mfhd</b> -- <i>{@link ISO14496_Box_MFHD Movie Fragment Header Box}</i>
+ *   <li>traf -- <i>{@link ISO14496_Box_TRAF Track Fragment Box}</i>
+ *     <ul>
+ *     <li><b>tfhd</b> -- <i>{@link ISO14496_Box_TFHD Track Fragment Header Box}</i>
+ *     <li>trun -- <i>{@link ISO14496_Box_TRUN Track Fragment Run}</i>
+ *     <li>sdtp -- <i>{@link ISO14496_Box_SDTP Independent and Disposable Samples}</i>
+ *     <li>sbgp -- <i>{@link ISO14496_Box_SBGP SampleToGroup Box}</i>
+ *     <li>subs -- <i>{@link ISO14496_Box_SUBS Sub-Sample Information Box}</i>
+ *     </ul>
+ *   </ul>
+ * <li>mfra -- <i>{@link ISO14496_Box_MFRA Movie Fragment Random Access Box}</i>
+ *   <ul>
+ *   <li>tfra -- <i>{@link ISO14496_Box_TFRA Track Fragment Random Access Box}</i>
+ *   <li><b>mfro</b> -- <i>{@link ISO14496_Box_MFRO Movie Fragment Random Access Offset Box}</i>
+ *   </ul>
+ * <li>mdat -- <i>{@link ISO14496_Box_MDAT Media Data Box}</i>
+ * <li>free -- <i>{@link ISO14496_Box_FREE Free Space Box}</i>
+ * <li>skip -- <i>{@link ISO14496_Box_SKIP Free Space Box}</i>
+ *   <ul>
+ *   <li>udta -- <i>{@link ISO14496_Box_UDTA User Data Box}</i>
+ *     <ul>
+ *     <li>cprt -- <i>{@link ISO14496_Box_CPRT Copyright Box}</i>
+ *     </ul>
+ *   </ul>
+ * <li>meta -- <i>{@link ISO14496_Box_META The Meta Box}</i>
+ *   <ul>
+ *   <li><b>hdlr</b> -- <i>{@link ISO14496_Box_HDLR Handler Reference Box}</i>; declares the metadata type
+ *   <li>dinf -- <i>{@link ISO14496_Box_DINF Data Information Box}</i>
+ *     <ul>
+ *     <li>dref -- <i>{@link ISO14496_Box_DREF Data Reference Box}</i>; declares source(s) of metadata items
+ *     </ul>
+ *   <li>ipmc -- <i>{@link ISO14496_Box_IPMC IPMP Control Box}</i>
+ *   <li>iloc -- <i>{@link ISO14496_Box_ILOC Item Location Box}</i>
+ *   <li>ipro -- <i>{@link ISO14496_Box_IPRO Item Protection Box}</i>
+ *     <ul>
+ *     <li>sinf -- <i>{@link ISO14496_Box_SINF Protection Scheme Information Box}</i>
+ *       <ul>
+ *       <li>frma -- <i>{@link ISO14496_Box_FRMA Original Format Box}</i>
+ *       <li>imif -- <i>{@link ISO14496_Box_IMIF IPMP Information Box}</i>
+ *       <li>schm -- <i>{@link ISO14496_Box_SCHM Scheme Type Box}</i>
+ *       <li>schi -- <i>{@link ISO14496_Box_SCHI Scheme Information Box}</i>
+ *       </ul>
+ *     </ul>
+ *   <li>iinf -- <i>{@link ISO14496_Box_IINF Item Information Box}</i>
+ *     <ul>
+ *     <li>infe -- <i>{@link ISO14496_Box_INFE Item Information Entry Box}</i>
+ *     </ul>
+ *   <li>xml -- <i>{@link ISO14496_Box_XML XML Box}</i>
+ *   <li>bxml -- <i>{@link ISO14496_Box_BXML Binary XML Box}</i>
+ *   <li>pitm -- <i>{@link ISO14496_Box_PITM Primary Item Reference Box}</i>
+ *   </ul>
+ * </ul>
+ *
+ * There are two non-standard extensions to the ISO 14496 standard that add the
+ * ability to include file meta information. Both the boxes reside under
+ * moov.udta.meta.
+ *
+ * <ul>
+ * <li><i>moov</i> -- <i>{@link ISO14496_Box_MOOV Movie Box}</i>; container for all the metadata
+ * <li><i>udta</i> -- <i>{@link ISO14496_Box_UDTA User Data Box}</i>
+ * <li><i>meta</i> -- <i>{@link ISO14496_Box_META The Meta Box}</i>
+ *   <ul>
+ *   <li>ilst -- <i>{@link ISO14496_Box_ILST The iTunes/iPod Tag Container Box}</i>
+ *   <li>id32 -- <i>{@link ISO14496_Box_ID32 The ID3v2 Box}</i>
+ *   </ul>
+ * </ul>
  * 
  * @package    php-reader
  * @subpackage ISO 14496

src/ISO14496/Box.php

@@ -242,11 +242,25 @@ class ISO14496_Box
    * @param string $name The box or field name.
    * @return mixed
    */
-  public function __get($name) {
+  public function __get($name)
+  {
     if ($this->isContainer() && isset($this->_boxes[$name]))
       return $this->_boxes[$name][0];
     if (method_exists($this, "get" . ucfirst($name)))
       return call_user_func(array($this, "get" . ucfirst($name)));
     throw new ISO14496_Exception("Unknown box/field: " . $name);
   }
+  
+  /**
+   * Magic function so that isset($obj->value) will work. This method checks
+   * whether the box is a container and contains a box that matches the
+   * identifier.
+   *
+   * @param string $name The box name.
+   * @return boolean
+   */
+  public function __isset($name)
+  {
+    return ($this->isContainer() && isset($this->_boxes[$name]));
+  }
 }

src/ISO14496/Box/BXML.php

@@ -65,7 +65,6 @@ final class ISO14496_Box_BXML extends ISO14496_Box_Full
    * the ISO Base Media file.
    *
    * @param Reader  $reader The reader object.
-   * @todo The sample flags could be parsed further
    */
   public function __construct($reader)
   {

src/ISO14496/Box/CO64.php

@@ -80,15 +80,13 @@ final class ISO14496_Box_CO64 extends ISO14496_Box_Full
     
     $entryCount = $this->_reader->readUInt32BE();
     for ($i = 1; $i < $entryCount; $i++)
-      $this->_chunkOffsetTable[$i] = array
+      $this->_chunkOffsetTable[$i] = $this->_reader->readInt64BE();
-        ("chunkOffset" => $this->_reader->readInt64BE());
   }
   
   /**
-   * Returns an array of values. Each entry is an array containing the following
+   * Returns an array of values. Each entry has the entry number as its index
-   * keys.
+   * and a 64 bit integer that gives the offset of the start of a chunk into
-   *   o chunkOffset -- a 64 bit integer that gives the offset of the start of a
+   * its containing media file as its value.
-   *     chunk into its containing media file.
    *
    * @return Array
    */

src/ISO14496/Box/ELST.php

@@ -92,7 +92,7 @@ final class ISO14496_Box_ELST extends ISO14496_Box_Full
    *     media time scale units, in composition time). If this field is set to
    *     –1, it is an empty edit. The last edit in a track shall never be an
    *     empty edit. Any difference between the duration in the
-   *     {@link ISO14496_Box_MVHD Movie Header Box}, and the track’s duration is
+   *     {@link ISO14496_Box_MVHD Movie Header Box}, and the track's duration is
    *     expressed as an implicit empty edit at the end.
    *   o mediaRate: the relative rate at which to play the media corresponding
    *     to this edit segment. If this value is 0, then the edit is specifying

src/ISO14496/Box/HDLR.php

@@ -76,7 +76,7 @@ final class ISO14496_Box_HDLR extends ISO14496_Box_Full
     $this->_reader->skip(4);
     $this->_handlerType = $this->_reader->read(4);
     $this->_reader->skip(12);
-    $this->_name = $this->_reader->read
+    $this->_name = $this->_reader->readString8
       ($this->_offset + $this->_size - $this->_reader->getOffset());
   }
   

src/ISO14496/Box/MINF.php

@@ -52,4 +52,16 @@ require_once("ISO14496/Box.php");
  */
 final class ISO14496_Box_MINF extends ISO14496_Box
 {
+  /**
+   * Constructs the class with given parameters and reads box related data from
+   * the ISO Base Media file.
+   *
+   * @param Reader $reader The reader object.
+   */
+  public function __construct($reader)
+  {
+    parent::__construct($reader);
+    $this->setContainer(true);
+    $this->constructBoxes();
+  }
 }

src/ISO14496/Box/MVHD.php

@@ -131,7 +131,7 @@ final class ISO14496_Box_MVHD extends ISO14496_Box_Full
   
   /**
    * Returns the length of the presentation in the indicated timescale. This
-   * property is derived from the presentation’s tracks: the value of this field
+   * property is derived from the presentation's tracks: the value of this field
    * corresponds to the duration of the longest track in the presentation.
    * 
    * @return integer

src/ISO14496/Box/PITM.php

@@ -65,7 +65,6 @@ final class ISO14496_Box_PITM extends ISO14496_Box_Full
    * the ISO Base Media file.
    *
    * @param Reader  $reader The reader object.
-   * @todo The sample flags could be parsed further
    */
   public function __construct($reader)
   {

src/ISO14496/Box/SBGP.php

@@ -62,7 +62,7 @@ require_once("ISO14496/Box/Full.php");
  * @license    http://code.google.com/p/php-reader/wiki/License New BSD License
  * @version    $Rev$
  */
-final class ISO14496_Box_STGP extends ISO14496_Box_Full
+final class ISO14496_Box_SBGP extends ISO14496_Box_Full
 {
   /** @var integer */
   private $_groupingType;

src/ISO14496/Box/STCO.php

@@ -79,16 +79,14 @@ final class ISO14496_Box_STCO extends ISO14496_Box_Full
     parent::__construct($reader);
     
     $entryCount = $this->_reader->readUInt32BE();
-    for ($i = 0; $i < $entryCount; $i++)
+    for ($i = 1; $i < $entryCount; $i++)
-      $this->_chunkOffsetTable[] = array
+      $this->_chunkOffsetTable[$i] = $this->_reader->readUInt32BE();
-        ("chunkOffset" => $this->_reader->readUInt32BE());
   }
   
   /**
-   * Returns an array of values. Each entry is an array containing the following
+   * Returns an array of values. Each entry has the entry number as its index
-   * keys.
+   * and a 32 bit integer that gives the offset of the start of a chunk into
-   *   o chunkOffset -- a 32 bit integer that gives the offset of the start of a
+   * its containing media file as its value.
-   *     chunk into its containing media file.
    *
    * @return Array
    */

src/ISO14496/Box/STSS.php

@@ -69,15 +69,13 @@ final class ISO14496_Box_STSS extends ISO14496_Box_Full
     
     $entryCount = $this->_reader->readUInt32BE();
     for ($i = 1; $i < $entryCount; $i++)
-      $this->_syncSampleTable[$i] = array
+      $this->_syncSampleTable[$i] = $this->_reader->readUInt32BE();
-        ("sampleNumber" => $this->_reader->readUInt32BE());
   }
   
   /**
-   * Returns an array of values. Each entry is an array containing the following
+   * Returns an array of values. Each entry has the entry number as its index
-   * keys.
+   * and an integer that gives the numbers of the samples that are random access
-   *   o sampleNumber -- gives the numbers of the samples that are random access
+   * points in the stream as its value.
-   *     points in the stream.
    *
    * @return Array
    */

src/ISO14496/Box/TKHD.php

@@ -146,7 +146,7 @@ final class ISO14496_Box_TKHD extends ISO14496_Box_Full
   /**
    * Returns the duration of this track (in the timescale indicated in the
    * {@link MVHD Movie Header Box}). The value of this field is equal to the sum
-   * of the durations of all of the track’s edits. If there is no edit list,
+   * of the durations of all of the track's edits. If there is no edit list,
    * then the duration is the sum of the sample durations, converted into the
    * timescale in the {@link MVHD Movie Header Box}. If the duration of this
    * track cannot be determined then duration is set to all 32-bit maxint.

src/ISO14496/Box/XML.php

@@ -66,7 +66,6 @@ final class ISO14496_Box_XML extends ISO14496_Box_Full
    * the ISO Base Media file.
    *
    * @param Reader  $reader The reader object.
-   * @todo The sample flags could be parsed further
    */
   public function __construct($reader)
   {

src/Transform.php

@@ -133,6 +133,62 @@ final class Transform
     return $int;
   }
   
+  /**
+   * Returns signed 32-bit integer as little-endian ordered binary data.
+   *
+   * @param integer $value The input value.
+   * @return string
+   */
+  public static function toInt32LE($value)
+  {
+    if (self::fromInt32("\x00\x00\x00\x01") == 1)
+      return strrev(self::toInt32($value));
+    else 
+      return self::toInt32($value);
+  }
+  
+  /**
+   * Returns little-endian ordered binary data as signed 32-bit integer.
+   * 
+   * @param string $value The binary data string.
+   * @return integer
+   */
+  public static function fromInt32LE($value)
+  {
+    if (self::fromInt32("\x00\x00\x00\x01") == 1)
+      return self::fromInt32(strrev($value));
+    else
+      return self::fromInt32($value);
+  }
+  
+  /**
+   * Returns signed 32-bit integer as big-endian ordered binary data.
+   *
+   * @param integer $value The input value.
+   * @return string
+   */
+  public static function toInt32BE($value)
+  {
+    if (self::fromInt32("\x00\x00\x00\x01") == 1)
+      return self::toInt32($value);
+    else 
+      return strrev(self::toInt32($value));
+  }
+  
+  /**
+   * Returns big-endian ordered binary data as signed 32-bit integer.
+   * 
+   * @param string $value The binary data string.
+   * @return integer
+   */
+  public static function fromInt32BE($value)
+  {
+    if (self::fromInt32("\x00\x00\x00\x01") == 1)
+      return self::fromInt32($value);
+    else
+      return self::fromInt32(strrev($value));
+  }
+  
   /**
    * Returns unsigned 32-bit integer as little-endian ordered binary data.
    *
@@ -202,6 +258,62 @@ final class Transform
     return $int;
   }
   
+  /**
+   * Returns signed 16-bit integer as little-endian ordered binary data.
+   *
+   * @param integer $value The input value.
+   * @return string
+   */
+  public static function toInt16LE($value)
+  {
+    if (self::fromInt16("\x00\x01") == 1)
+      return strrev(self::toInt16($value));
+    else 
+      return self::toInt16($value);
+  }
+  
+  /**
+   * Returns little-endian ordered binary data as signed 16-bit integer.
+   *
+   * @param string $value The binary data string.
+   * @return integer
+   */
+  public static function fromInt16LE($value)
+  {
+    if (self::fromInt16("\x00\x01") == 1)
+      return self::fromInt16(strrev($value));
+    else
+      return self::fromInt16($value);
+  }
+  
+  /**
+   * Returns signed 16-bit integer as big-endian ordered binary data.
+   *
+   * @param integer $value The input value.
+   * @return string
+   */
+  public static function toInt16BE($value)
+  {
+    if (self::fromInt16("\x00\x01") == 1)
+      return self::toInt16($value);
+    else 
+      return strrev(self::toInt16($value));
+  }
+  
+  /**
+   * Returns big-endian ordered binary data as signed 16-bit integer.
+   *
+   * @param string $value The binary data string.
+   * @return integer
+   */
+  public static function fromInt16BE($value)
+  {
+    if (self::fromInt16("\x00\x01") == 1)
+      return self::fromInt16($value);
+    else
+      return self::fromInt16(strrev($value));
+  }
+  
   /**
    * Returns machine endian ordered binary data as unsigned 16-bit integer.
    * 

tests/TestTransform.php

@@ -70,6 +70,23 @@ final class TestTransform extends PHPUnit_Framework_TestCase
   {
     $this->assertEquals
       (0x7fffffff, Transform::fromInt32(Transform::toInt32(0x7fffffff)));
+    $this->assertEquals(-1, Transform::fromInt32(Transform::toInt32(-1)));
+  }
+
+  function testInt32LE()
+  {
+    $this->assertEquals(1, Transform::fromInt32LE("\x01\x00\x00\x00"));
+    $this->assertEquals
+      (0x7fffffff, Transform::fromInt32LE(Transform::toInt32LE(0x7fffffff)));
+    $this->assertEquals(-1, Transform::fromInt32LE(Transform::toInt32LE(-1)));
+  }
+
+  function testInt32BE()
+  {
+    $this->assertEquals(1, Transform::fromInt32BE("\x00\x00\x00\x01"));
+    $this->assertEquals
+      (0x7fffffff, Transform::fromInt32BE(Transform::toInt32BE(0x7fffffff)));
+    $this->assertEquals(-1, Transform::fromInt32BE(Transform::toInt32BE(-1)));
   }
 
   function testUInt32LE()
@@ -92,6 +109,23 @@ final class TestTransform extends PHPUnit_Framework_TestCase
   {
     $this->assertEquals
       (0x7fff, Transform::fromInt16(Transform::toInt16(0x7fff)));
+    $this->assertEquals(-1, Transform::fromInt16(Transform::toInt16(-1)));
+  }
+
+  function testInt16LE()
+  {
+    $this->assertEquals(1, Transform::fromInt16LE("\x01\x00"));
+    $this->assertEquals
+      (0x7fff, Transform::fromInt16LE(Transform::toInt16LE(0x7fff)));
+    $this->assertEquals(-1, Transform::fromInt16LE(Transform::toInt16LE(-1)));
+  }
+
+  function testInt16BE()
+  {
+    $this->assertEquals(1, Transform::fromInt16BE("\x00\x01"));
+    $this->assertEquals
+      (0x7fff, Transform::fromInt16BE(Transform::toInt16BE(0x7fff)));
+    $this->assertEquals(-1, Transform::fromInt16BE(Transform::toInt16BE(-1)));
   }
 
   function testUInt16LE()