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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /dom/media/BitReader.h
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'dom/media/BitReader.h')
-rw-r--r--dom/media/BitReader.h54
1 files changed, 54 insertions, 0 deletions
diff --git a/dom/media/BitReader.h b/dom/media/BitReader.h
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+++ b/dom/media/BitReader.h
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef BIT_READER_H_
+#define BIT_READER_H_
+
+#include "MediaData.h"
+
+namespace mozilla {
+
+class BitReader {
+ public:
+ explicit BitReader(const MediaByteBuffer* aBuffer);
+ BitReader(const MediaByteBuffer* aBuffer, size_t aBits);
+ BitReader(const uint8_t* aBuffer, size_t aBits);
+ ~BitReader();
+ uint32_t ReadBits(size_t aNum);
+ bool ReadBit() { return ReadBits(1) != 0; }
+ uint32_t ReadU32() { return ReadBits(32); }
+ uint64_t ReadU64();
+
+ // Read the UTF-8 sequence and convert it to its 64-bit UCS-4 encoded form.
+ // Return 0xfffffffffffffff if sequence was invalid.
+ uint64_t ReadUTF8();
+ // Read unsigned integer Exp-Golomb-coded.
+ uint32_t ReadUE();
+ // Read signed integer Exp-Golomb-coded.
+ int32_t ReadSE();
+ // Read unsigned integer Little Endian Base 128 coded.
+ // Limited to unsigned 64 bits.
+ CheckedUint64 ReadULEB128();
+
+ // Return the number of bits parsed so far;
+ size_t BitCount() const;
+ // Return the number of bits left.
+ size_t BitsLeft() const;
+
+ // Return RBSP bit length.
+ static uint32_t GetBitLength(const MediaByteBuffer* aNAL);
+
+ private:
+ void FillReservoir();
+ const uint8_t* mData;
+ const size_t mOriginalBitSize;
+ size_t mTotalBitsLeft;
+ size_t mSize; // Size left in bytes
+ uint32_t mReservoir; // Left-aligned bits
+ size_t mNumBitsLeft; // Number of bits left in reservoir.
+};
+
+} // namespace mozilla
+
+#endif // BIT_READER_H_