Index: media/filters/vp9_raw_bits_reader.h |
diff --git a/media/filters/vp9_raw_bits_reader.h b/media/filters/vp9_raw_bits_reader.h |
new file mode 100644 |
index 0000000000000000000000000000000000000000..38f54a3cc2f0344077ab130dca9a2a1713649a51 |
--- /dev/null |
+++ b/media/filters/vp9_raw_bits_reader.h |
@@ -0,0 +1,62 @@ |
+// Copyright 2015 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#ifndef MEDIA_FILTERS_VP9_RAW_BITS_READER_ |
+#define MEDIA_FILTERS_VP9_RAW_BITS_READER_ |
+ |
+#include <stddef.h> |
+#include <stdint.h> |
+ |
+#include "base/macros.h" |
+#include "base/memory/scoped_ptr.h" |
+#include "media/base/media_export.h" |
+ |
+namespace media { |
+ |
+class BitReader; |
+ |
+// A class to read raw bits stream. See VP9 spec, "RAW-BITS DECODING" section |
+// for detail. |
+class MEDIA_EXPORT Vp9RawBitsReader { |
+ public: |
+ Vp9RawBitsReader(); |
+ ~Vp9RawBitsReader(); |
+ |
+ // |data| is the input buffer with |size| bytes. |
+ void Initialize(const uint8_t* data, size_t size); |
+ |
+ // Returns true if none of the reads since the last Initialize() call has |
+ // gone beyond the end of available data. |
+ bool IsValid() const { return valid_; } |
+ |
+ // Returns how many bytes were read since the last Initialize() call. |
+ // Partial bytes will be counted as one byte. For example, it will return 1 |
+ // if 3 bits were read. |
+ size_t GetBytesRead() const; |
+ |
+ // Reads one bit. |
+ // If the read goes beyond the end of buffer, the return value is undefined. |
+ int ReadBit(); |
+ |
+ // Reads a literal with |bits| bits. |
+ // If the read goes beyond the end of buffer, the return value is undefined. |
+ int ReadLiteral(int bits); |
+ |
+ // Reads a signed literal with |bits| bits (not including the sign bit). |
+ // If the read goes beyond the end of buffer, the return value is undefined. |
+ int ReadSignedLiteral(int bits); |
+ |
+ private: |
+ scoped_ptr<BitReader> reader_; |
+ |
+ // Indicates if none of the reads since the last Initialize() call has gone |
+ // beyond the end of available data. |
+ bool valid_; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(Vp9RawBitsReader); |
+}; |
+ |
+} // namespace media |
+ |
+#endif // MEDIA_FILTERS_VP9_RAW_BITS_READER_ |