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<li class="navelem"><a class="el" href="../../dir_3f8eec2fc361645de4b1ec14c19fffc7.html">packager</a></li><li class="navelem"><a class="el" href="../../dir_f99dae54fe7170f791f339b952d5067a.html">media</a></li><li class="navelem"><a class="el" href="../../dir_64597db6ac7a9160e951a4226a03f10e.html">codecs</a></li> </ul>
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<div class="title">h26x_bit_reader.cc</div> </div>
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<div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">// Copyright 2014 The Chromium Authors. All rights reserved.</span></div>
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<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment">// Use of this source code is governed by a BSD-style license that can be</span></div>
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<div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment">// found in the LICENSE file.</span></div>
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<div class="line"><a name="l00004"></a><span class="lineno"> 4</span>  </div>
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<div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="preprocessor">#include "packager/base/logging.h"</span></div>
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<div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="preprocessor">#include "packager/media/codecs/h26x_bit_reader.h"</span></div>
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<div class="line"><a name="l00007"></a><span class="lineno"> 7</span>  </div>
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<div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="keyword">namespace </span><a class="code" href="../../d8/daf/namespaceshaka.html">shaka</a> {</div>
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<div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="keyword">namespace </span>media {</div>
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<div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="keyword">namespace </span>{</div>
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<div class="line"><a name="l00011"></a><span class="lineno"> 11</span>  </div>
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<div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="comment">// Check if any bits in the least significant |valid_bits| are set to 1.</span></div>
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<div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="keywordtype">bool</span> CheckAnyBitsSet(<span class="keywordtype">int</span> <span class="keywordtype">byte</span>, <span class="keywordtype">int</span> valid_bits) {</div>
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<div class="line"><a name="l00014"></a><span class="lineno"> 14</span>  <span class="keywordflow">return</span> (<span class="keywordtype">byte</span> & ((1 << valid_bits) - 1)) != 0;</div>
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<div class="line"><a name="l00015"></a><span class="lineno"> 15</span> }</div>
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<div class="line"><a name="l00016"></a><span class="lineno"> 16</span>  </div>
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<div class="line"><a name="l00017"></a><span class="lineno"> 17</span> } <span class="comment">// namespace</span></div>
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<div class="line"><a name="l00018"></a><span class="lineno"> 18</span>  </div>
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<div class="line"><a name="l00019"></a><span class="lineno"> 19</span> H26xBitReader::H26xBitReader()</div>
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<div class="line"><a name="l00020"></a><span class="lineno"> 20</span>  : data_(NULL),</div>
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<div class="line"><a name="l00021"></a><span class="lineno"> 21</span>  bytes_left_(0),</div>
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<div class="line"><a name="l00022"></a><span class="lineno"> 22</span>  curr_byte_(0),</div>
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<div class="line"><a name="l00023"></a><span class="lineno"> 23</span>  num_remaining_bits_in_curr_byte_(0),</div>
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<div class="line"><a name="l00024"></a><span class="lineno"> 24</span>  prev_two_bytes_(0),</div>
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<div class="line"><a name="l00025"></a><span class="lineno"> 25</span>  emulation_prevention_bytes_(0) {}</div>
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<div class="line"><a name="l00026"></a><span class="lineno"> 26</span>  </div>
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<div class="line"><a name="l00027"></a><span class="lineno"> 27</span> H26xBitReader::~H26xBitReader() {}</div>
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<div class="line"><a name="l00028"></a><span class="lineno"> 28</span>  </div>
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<div class="line"><a name="l00029"></a><span class="lineno"> 29</span> <span class="keywordtype">bool</span> H26xBitReader::Initialize(<span class="keyword">const</span> uint8_t* data, off_t size) {</div>
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<div class="line"><a name="l00030"></a><span class="lineno"> 30</span>  DCHECK(data);</div>
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<div class="line"><a name="l00031"></a><span class="lineno"> 31</span>  </div>
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<div class="line"><a name="l00032"></a><span class="lineno"> 32</span>  <span class="keywordflow">if</span> (size < 1)</div>
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<div class="line"><a name="l00033"></a><span class="lineno"> 33</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00034"></a><span class="lineno"> 34</span>  </div>
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<div class="line"><a name="l00035"></a><span class="lineno"> 35</span>  data_ = data;</div>
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<div class="line"><a name="l00036"></a><span class="lineno"> 36</span>  bytes_left_ = size;</div>
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<div class="line"><a name="l00037"></a><span class="lineno"> 37</span>  num_remaining_bits_in_curr_byte_ = 0;</div>
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<div class="line"><a name="l00038"></a><span class="lineno"> 38</span>  <span class="comment">// Initially set to 0xffff to accept all initial two-byte sequences.</span></div>
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<div class="line"><a name="l00039"></a><span class="lineno"> 39</span>  prev_two_bytes_ = 0xffff;</div>
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<div class="line"><a name="l00040"></a><span class="lineno"> 40</span>  emulation_prevention_bytes_ = 0;</div>
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<div class="line"><a name="l00041"></a><span class="lineno"> 41</span>  </div>
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<div class="line"><a name="l00042"></a><span class="lineno"> 42</span>  <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
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<div class="line"><a name="l00043"></a><span class="lineno"> 43</span> }</div>
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<div class="line"><a name="l00044"></a><span class="lineno"> 44</span>  </div>
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<div class="line"><a name="l00045"></a><span class="lineno"> 45</span> <span class="keywordtype">bool</span> H26xBitReader::UpdateCurrByte() {</div>
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<div class="line"><a name="l00046"></a><span class="lineno"> 46</span>  <span class="keywordflow">if</span> (bytes_left_ < 1)</div>
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<div class="line"><a name="l00047"></a><span class="lineno"> 47</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00048"></a><span class="lineno"> 48</span>  </div>
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<div class="line"><a name="l00049"></a><span class="lineno"> 49</span>  <span class="comment">// Emulation prevention three-byte detection.</span></div>
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<div class="line"><a name="l00050"></a><span class="lineno"> 50</span>  <span class="comment">// If a sequence of 0x000003 is found, skip (ignore) the last byte (0x03).</span></div>
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<div class="line"><a name="l00051"></a><span class="lineno"> 51</span>  <span class="keywordflow">if</span> (*data_ == 0x03 && (prev_two_bytes_ & 0xffff) == 0) {</div>
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<div class="line"><a name="l00052"></a><span class="lineno"> 52</span>  <span class="comment">// Detected 0x000003, skip last byte.</span></div>
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<div class="line"><a name="l00053"></a><span class="lineno"> 53</span>  ++data_;</div>
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<div class="line"><a name="l00054"></a><span class="lineno"> 54</span>  --bytes_left_;</div>
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<div class="line"><a name="l00055"></a><span class="lineno"> 55</span>  ++emulation_prevention_bytes_;</div>
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<div class="line"><a name="l00056"></a><span class="lineno"> 56</span>  <span class="comment">// Need another full three bytes before we can detect the sequence again.</span></div>
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<div class="line"><a name="l00057"></a><span class="lineno"> 57</span>  prev_two_bytes_ = 0xffff;</div>
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<div class="line"><a name="l00058"></a><span class="lineno"> 58</span>  </div>
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<div class="line"><a name="l00059"></a><span class="lineno"> 59</span>  <span class="keywordflow">if</span> (bytes_left_ < 1)</div>
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<div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00061"></a><span class="lineno"> 61</span>  }</div>
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<div class="line"><a name="l00062"></a><span class="lineno"> 62</span>  </div>
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<div class="line"><a name="l00063"></a><span class="lineno"> 63</span>  <span class="comment">// Load a new byte and advance pointers.</span></div>
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<div class="line"><a name="l00064"></a><span class="lineno"> 64</span>  curr_byte_ = *data_++ & 0xff;</div>
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<div class="line"><a name="l00065"></a><span class="lineno"> 65</span>  --bytes_left_;</div>
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<div class="line"><a name="l00066"></a><span class="lineno"> 66</span>  num_remaining_bits_in_curr_byte_ = 8;</div>
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<div class="line"><a name="l00067"></a><span class="lineno"> 67</span>  </div>
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<div class="line"><a name="l00068"></a><span class="lineno"> 68</span>  prev_two_bytes_ = (prev_two_bytes_ << 8) | curr_byte_;</div>
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<div class="line"><a name="l00069"></a><span class="lineno"> 69</span>  </div>
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<div class="line"><a name="l00070"></a><span class="lineno"> 70</span>  <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
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<div class="line"><a name="l00071"></a><span class="lineno"> 71</span> }</div>
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<div class="line"><a name="l00072"></a><span class="lineno"> 72</span>  </div>
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<div class="line"><a name="l00073"></a><span class="lineno"> 73</span> <span class="comment">// Read |num_bits| (1 to 31 inclusive) from the stream and return them</span></div>
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<div class="line"><a name="l00074"></a><span class="lineno"> 74</span> <span class="comment">// in |out|, with first bit in the stream as MSB in |out| at position</span></div>
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<div class="line"><a name="l00075"></a><span class="lineno"> 75</span> <span class="comment">// (|num_bits| - 1).</span></div>
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<div class="line"><a name="l00076"></a><span class="lineno"> 76</span> <span class="keywordtype">bool</span> H26xBitReader::ReadBits(<span class="keywordtype">int</span> num_bits, <span class="keywordtype">int</span>* out) {</div>
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<div class="line"><a name="l00077"></a><span class="lineno"> 77</span>  <span class="keywordtype">int</span> bits_left = num_bits;</div>
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<div class="line"><a name="l00078"></a><span class="lineno"> 78</span>  *out = 0;</div>
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<div class="line"><a name="l00079"></a><span class="lineno"> 79</span>  DCHECK(num_bits <= 31);</div>
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<div class="line"><a name="l00080"></a><span class="lineno"> 80</span>  </div>
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<div class="line"><a name="l00081"></a><span class="lineno"> 81</span>  <span class="keywordflow">while</span> (num_remaining_bits_in_curr_byte_ < bits_left) {</div>
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<div class="line"><a name="l00082"></a><span class="lineno"> 82</span>  <span class="comment">// Take all that's left in current byte, shift to make space for the rest.</span></div>
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<div class="line"><a name="l00083"></a><span class="lineno"> 83</span>  *out |= (curr_byte_ << (bits_left - num_remaining_bits_in_curr_byte_));</div>
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<div class="line"><a name="l00084"></a><span class="lineno"> 84</span>  bits_left -= num_remaining_bits_in_curr_byte_;</div>
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<div class="line"><a name="l00085"></a><span class="lineno"> 85</span>  </div>
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<div class="line"><a name="l00086"></a><span class="lineno"> 86</span>  <span class="keywordflow">if</span> (!UpdateCurrByte())</div>
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<div class="line"><a name="l00087"></a><span class="lineno"> 87</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00088"></a><span class="lineno"> 88</span>  }</div>
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<div class="line"><a name="l00089"></a><span class="lineno"> 89</span>  </div>
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<div class="line"><a name="l00090"></a><span class="lineno"> 90</span>  *out |= (curr_byte_ >> (num_remaining_bits_in_curr_byte_ - bits_left));</div>
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<div class="line"><a name="l00091"></a><span class="lineno"> 91</span>  *out &= ((1 << num_bits) - 1);</div>
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<div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  num_remaining_bits_in_curr_byte_ -= bits_left;</div>
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<div class="line"><a name="l00093"></a><span class="lineno"> 93</span>  </div>
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<div class="line"><a name="l00094"></a><span class="lineno"> 94</span>  <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
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<div class="line"><a name="l00095"></a><span class="lineno"> 95</span> }</div>
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<div class="line"><a name="l00096"></a><span class="lineno"> 96</span>  </div>
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<div class="line"><a name="l00097"></a><span class="lineno"> 97</span> <span class="keywordtype">bool</span> H26xBitReader::SkipBits(<span class="keywordtype">int</span> num_bits) {</div>
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<div class="line"><a name="l00098"></a><span class="lineno"> 98</span>  <span class="keywordtype">int</span> bits_left = num_bits;</div>
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<div class="line"><a name="l00099"></a><span class="lineno"> 99</span>  <span class="keywordflow">while</span> (num_remaining_bits_in_curr_byte_ < bits_left) {</div>
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<div class="line"><a name="l00100"></a><span class="lineno"> 100</span>  bits_left -= num_remaining_bits_in_curr_byte_;</div>
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<div class="line"><a name="l00101"></a><span class="lineno"> 101</span>  <span class="keywordflow">if</span> (!UpdateCurrByte())</div>
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<div class="line"><a name="l00102"></a><span class="lineno"> 102</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00103"></a><span class="lineno"> 103</span>  }</div>
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<div class="line"><a name="l00104"></a><span class="lineno"> 104</span>  </div>
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<div class="line"><a name="l00105"></a><span class="lineno"> 105</span>  num_remaining_bits_in_curr_byte_ -= bits_left;</div>
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<div class="line"><a name="l00106"></a><span class="lineno"> 106</span>  <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
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<div class="line"><a name="l00107"></a><span class="lineno"> 107</span> }</div>
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<div class="line"><a name="l00108"></a><span class="lineno"> 108</span>  </div>
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<div class="line"><a name="l00109"></a><span class="lineno"> 109</span> <span class="keywordtype">bool</span> H26xBitReader::ReadUE(<span class="keywordtype">int</span>* val) {</div>
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<div class="line"><a name="l00110"></a><span class="lineno"> 110</span>  <span class="keywordtype">int</span> num_bits = -1;</div>
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<div class="line"><a name="l00111"></a><span class="lineno"> 111</span>  <span class="keywordtype">int</span> bit;</div>
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<div class="line"><a name="l00112"></a><span class="lineno"> 112</span>  <span class="keywordtype">int</span> rest;</div>
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<div class="line"><a name="l00113"></a><span class="lineno"> 113</span>  </div>
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<div class="line"><a name="l00114"></a><span class="lineno"> 114</span>  <span class="comment">// Count the number of contiguous zero bits.</span></div>
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<div class="line"><a name="l00115"></a><span class="lineno"> 115</span>  <span class="keywordflow">do</span> {</div>
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<div class="line"><a name="l00116"></a><span class="lineno"> 116</span>  <span class="keywordflow">if</span> (!ReadBits(1, &bit))</div>
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<div class="line"><a name="l00117"></a><span class="lineno"> 117</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00118"></a><span class="lineno"> 118</span>  num_bits++;</div>
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<div class="line"><a name="l00119"></a><span class="lineno"> 119</span>  } <span class="keywordflow">while</span> (bit == 0);</div>
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<div class="line"><a name="l00120"></a><span class="lineno"> 120</span>  </div>
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<div class="line"><a name="l00121"></a><span class="lineno"> 121</span>  <span class="keywordflow">if</span> (num_bits > 31)</div>
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<div class="line"><a name="l00122"></a><span class="lineno"> 122</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00123"></a><span class="lineno"> 123</span>  </div>
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<div class="line"><a name="l00124"></a><span class="lineno"> 124</span>  <span class="comment">// Calculate exp-Golomb code value of size num_bits.</span></div>
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<div class="line"><a name="l00125"></a><span class="lineno"> 125</span>  *val = (1 << num_bits) - 1;</div>
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<div class="line"><a name="l00126"></a><span class="lineno"> 126</span>  </div>
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<div class="line"><a name="l00127"></a><span class="lineno"> 127</span>  <span class="keywordflow">if</span> (num_bits > 0) {</div>
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<div class="line"><a name="l00128"></a><span class="lineno"> 128</span>  <span class="keywordflow">if</span> (!ReadBits(num_bits, &rest))</div>
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<div class="line"><a name="l00129"></a><span class="lineno"> 129</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00130"></a><span class="lineno"> 130</span>  *val += rest;</div>
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<div class="line"><a name="l00131"></a><span class="lineno"> 131</span>  }</div>
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<div class="line"><a name="l00132"></a><span class="lineno"> 132</span>  </div>
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<div class="line"><a name="l00133"></a><span class="lineno"> 133</span>  <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
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<div class="line"><a name="l00134"></a><span class="lineno"> 134</span> }</div>
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<div class="line"><a name="l00135"></a><span class="lineno"> 135</span>  </div>
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<div class="line"><a name="l00136"></a><span class="lineno"> 136</span> <span class="keywordtype">bool</span> H26xBitReader::ReadSE(<span class="keywordtype">int</span>* val) {</div>
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<div class="line"><a name="l00137"></a><span class="lineno"> 137</span>  <span class="keywordtype">int</span> ue;</div>
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<div class="line"><a name="l00138"></a><span class="lineno"> 138</span>  </div>
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<div class="line"><a name="l00139"></a><span class="lineno"> 139</span>  <span class="comment">// See Chapter 9 in the spec.</span></div>
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<div class="line"><a name="l00140"></a><span class="lineno"> 140</span>  <span class="keywordflow">if</span> (!ReadUE(&ue))</div>
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<div class="line"><a name="l00141"></a><span class="lineno"> 141</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00142"></a><span class="lineno"> 142</span>  </div>
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<div class="line"><a name="l00143"></a><span class="lineno"> 143</span>  <span class="keywordflow">if</span> (ue % 2 == 0)</div>
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<div class="line"><a name="l00144"></a><span class="lineno"> 144</span>  *val = -(ue / 2);</div>
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<div class="line"><a name="l00145"></a><span class="lineno"> 145</span>  <span class="keywordflow">else</span></div>
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<div class="line"><a name="l00146"></a><span class="lineno"> 146</span>  *val = ue / 2 + 1;</div>
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<div class="line"><a name="l00147"></a><span class="lineno"> 147</span>  </div>
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<div class="line"><a name="l00148"></a><span class="lineno"> 148</span>  <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
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<div class="line"><a name="l00149"></a><span class="lineno"> 149</span> }</div>
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<div class="line"><a name="l00150"></a><span class="lineno"> 150</span>  </div>
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<div class="line"><a name="l00151"></a><span class="lineno"> 151</span> off_t H26xBitReader::NumBitsLeft() {</div>
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<div class="line"><a name="l00152"></a><span class="lineno"> 152</span>  <span class="keywordflow">return</span> (num_remaining_bits_in_curr_byte_ + bytes_left_ * 8);</div>
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<div class="line"><a name="l00153"></a><span class="lineno"> 153</span> }</div>
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<div class="line"><a name="l00154"></a><span class="lineno"> 154</span>  </div>
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<div class="line"><a name="l00155"></a><span class="lineno"> 155</span> <span class="keywordtype">bool</span> H26xBitReader::HasMoreRBSPData() {</div>
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<div class="line"><a name="l00156"></a><span class="lineno"> 156</span>  <span class="comment">// Make sure we have more bits, if we are at 0 bits in current byte and</span></div>
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<div class="line"><a name="l00157"></a><span class="lineno"> 157</span>  <span class="comment">// updating current byte fails, we don't have more data anyway.</span></div>
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<div class="line"><a name="l00158"></a><span class="lineno"> 158</span>  <span class="keywordflow">if</span> (num_remaining_bits_in_curr_byte_ == 0 && !UpdateCurrByte())</div>
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<div class="line"><a name="l00159"></a><span class="lineno"> 159</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00160"></a><span class="lineno"> 160</span>  </div>
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<div class="line"><a name="l00161"></a><span class="lineno"> 161</span>  <span class="comment">// If there is no more RBSP data, then the remaining bits is the stop bit</span></div>
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<div class="line"><a name="l00162"></a><span class="lineno"> 162</span>  <span class="comment">// followed by zero paddings. So if there are 1s in the remaining bits</span></div>
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<div class="line"><a name="l00163"></a><span class="lineno"> 163</span>  <span class="comment">// excluding the current bit, then the current bit is not a stop bit,</span></div>
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<div class="line"><a name="l00164"></a><span class="lineno"> 164</span>  <span class="comment">// regardless of whether it is 1 or not. Therefore there is more data.</span></div>
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<div class="line"><a name="l00165"></a><span class="lineno"> 165</span>  <span class="keywordflow">if</span> (CheckAnyBitsSet(curr_byte_, num_remaining_bits_in_curr_byte_ - 1))</div>
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<div class="line"><a name="l00166"></a><span class="lineno"> 166</span>  <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
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<div class="line"><a name="l00167"></a><span class="lineno"> 167</span>  </div>
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<div class="line"><a name="l00168"></a><span class="lineno"> 168</span>  <span class="comment">// While the spec disallows it (7.4.1: "The last byte of the NAL unit shall</span></div>
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<div class="line"><a name="l00169"></a><span class="lineno"> 169</span>  <span class="comment">// not be equal to 0x00"), some streams have trailing null bytes anyway. We</span></div>
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<div class="line"><a name="l00170"></a><span class="lineno"> 170</span>  <span class="comment">// don't handle emulation prevention sequences because HasMoreRBSPData() is</span></div>
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<div class="line"><a name="l00171"></a><span class="lineno"> 171</span>  <span class="comment">// not used when parsing slices (where cabac_zero_word elements are legal).</span></div>
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<div class="line"><a name="l00172"></a><span class="lineno"> 172</span>  <span class="keywordflow">for</span> (off_t i = 0; i < bytes_left_; i++) {</div>
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<div class="line"><a name="l00173"></a><span class="lineno"> 173</span>  <span class="keywordflow">if</span> (data_[i] != 0)</div>
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<div class="line"><a name="l00174"></a><span class="lineno"> 174</span>  <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
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<div class="line"><a name="l00175"></a><span class="lineno"> 175</span>  }</div>
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<div class="line"><a name="l00176"></a><span class="lineno"> 176</span>  </div>
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<div class="line"><a name="l00177"></a><span class="lineno"> 177</span>  bytes_left_ = 0;</div>
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<div class="line"><a name="l00178"></a><span class="lineno"> 178</span>  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
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<div class="line"><a name="l00179"></a><span class="lineno"> 179</span> }</div>
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<div class="line"><a name="l00180"></a><span class="lineno"> 180</span>  </div>
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<div class="line"><a name="l00181"></a><span class="lineno"> 181</span> <span class="keywordtype">size_t</span> H26xBitReader::NumEmulationPreventionBytesRead() {</div>
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<div class="line"><a name="l00182"></a><span class="lineno"> 182</span>  <span class="keywordflow">return</span> emulation_prevention_bytes_;</div>
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<div class="line"><a name="l00183"></a><span class="lineno"> 183</span> }</div>
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<div class="line"><a name="l00184"></a><span class="lineno"> 184</span>  </div>
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<div class="line"><a name="l00185"></a><span class="lineno"> 185</span> } <span class="comment">// namespace media</span></div>
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<div class="line"><a name="l00186"></a><span class="lineno"> 186</span> } <span class="comment">// namespace shaka</span></div>
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</div><!-- fragment --></div><!-- contents -->
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<div class="ttc" id="anamespaceshaka_html"><div class="ttname"><a href="../../d8/daf/namespaceshaka.html">shaka</a></div><div class="ttdoc">All the methods that are virtual are virtual for mocking.</div><div class="ttdef"><b>Definition:</b> <a href="../../d4/d15/gflags__hex__bytes_8cc_source.html#l00011">gflags_hex_bytes.cc:11</a></div></div>
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