Split the bit reader functionalities from the byte stream provider.

media/base/bit_reader_h264_unittest.cc

+// Copyright (c) 2012 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.
+
+#include "media/base/bit_reader_h264.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace media {
+
+TEST(BitReaderH264Test, ReadStreamWithoutEscapeAndTrailingZeroBytes) {
+  const unsigned char rbsp[] = {0x01, 0x23, 0x45, 0x67, 0x89, 0xa0};
+  int dummy = 0;
+  BitReaderH264 reader(rbsp, sizeof(rbsp));
+
+  EXPECT_TRUE(reader.ReadBits(1, &dummy));
+  EXPECT_EQ(dummy, 0x00);
+  EXPECT_TRUE(reader.HasMoreRBSPData());
+
+  EXPECT_TRUE(reader.ReadBits(8, &dummy));
+  EXPECT_EQ(dummy, 0x02);
+  EXPECT_TRUE(reader.HasMoreRBSPData());
+
+  EXPECT_TRUE(reader.ReadBits(31, &dummy));
+  EXPECT_EQ(dummy, 0x23456789);
+  EXPECT_TRUE(reader.HasMoreRBSPData());
+
+  EXPECT_TRUE(reader.ReadBits(1, &dummy));
+  EXPECT_EQ(dummy, 1);
+  EXPECT_TRUE(reader.HasMoreRBSPData());
+
+  EXPECT_TRUE(reader.ReadBits(1, &dummy));
+  EXPECT_EQ(dummy, 0);
+  EXPECT_FALSE(reader.HasMoreRBSPData());
+}
+
+TEST(BitReaderH264Test, SingleByteStream) {
+  const unsigned char rbsp[] = {0x18};
+  int dummy = 0;
+  BitReaderH264 reader(rbsp, sizeof(rbsp));
+
+  EXPECT_TRUE(reader.HasMoreRBSPData());
+
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0x01);
+  EXPECT_FALSE(reader.HasMoreRBSPData());
+}
+
+TEST(BitReaderH264Test, StopBitOccupyFullByte) {
+  const unsigned char rbsp[] = {0xab, 0x80};
+  int dummy = 0;
+  BitReaderH264 reader(rbsp, sizeof(rbsp));
+
+  EXPECT_TRUE(reader.HasMoreRBSPData());
+
+  EXPECT_TRUE(reader.ReadBits(8, &dummy));
+  EXPECT_EQ(dummy, 0xab);
+  EXPECT_FALSE(reader.HasMoreRBSPData());
+}
+
+TEST(BitReaderH264Test, EmulationPreventionByte) {
+  const unsigned char rbsp[] = {0xac, 0x00, 0x00, 0x03, 0x01, 0x03, 0xdc};
+  int dummy = 0;
+  BitReaderH264 reader(rbsp, sizeof(rbsp));
+
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0xa);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0xc);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0x0);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0x0);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0x0);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0x0);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0x0);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0x1);
+
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0x0);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0x3);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0xd);
+  EXPECT_TRUE(reader.ReadBits(4, &dummy));
+  EXPECT_EQ(dummy, 0xc);
+}
+
+}  // namespace media