Reorganize bitstream converter classes.

media/base/h264_bitstream_converter.cc

Index: media/base/h264_bitstream_converter.cc
diff --git a/media/base/h264_bitstream_converter.cc b/media/base/h264_bitstream_converter.cc
deleted file mode 100644
index 4e154f218d4f4fc17e29c8d09a41e39f904c70fb..0000000000000000000000000000000000000000
--- a/media/base/h264_bitstream_converter.cc
+++ /dev/null
@@ -1,312 +0,0 @@
-// 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/h264_bitstream_converter.h"
-
-#include "base/logging.h"
-
-namespace media {
-
-static const uint8 kStartCodePrefix[3] = {0, 0, 1};
-
-// Helper function which determines whether NAL unit of given type marks
-// access unit boundary.
-static bool IsAccessUnitBoundaryNal(int nal_unit_type) {
-  // Check if this packet marks access unit boundary by checking the
-  // packet type.
-  if (nal_unit_type == 6 ||  // Supplemental enhancement information
-      nal_unit_type == 7 ||  // Picture parameter set
-      nal_unit_type == 8 ||  // Sequence parameter set
-      nal_unit_type == 9 ||  // Access unit delimiter
-      (nal_unit_type >= 14 && nal_unit_type <= 18)) {  // Reserved types
-    return true;
-  }
-  return false;
-}
-
-H264BitstreamConverter::H264BitstreamConverter()
-    : configuration_processed_(false),
-      first_nal_unit_in_access_unit_(true),
-      nal_unit_length_field_width_(0) {
-}
-
-H264BitstreamConverter::~H264BitstreamConverter() {}
-
-uint32 H264BitstreamConverter::ParseConfigurationAndCalculateSize(
-    const uint8* configuration_record,
-    uint32 configuration_record_size) {
-  // FFmpeg's AVCodecContext's extradata field contains the Decoder Specific
-  // Information from MP4 headers that contain the H.264 SPS and PPS members.
-  // ISO 14496-15 Chapter 5.2.4 AVCDecoderConfigurationRecord.
-  // AVCConfigurationRecord must be at least 7 bytes long.
-  if (configuration_record == NULL || configuration_record_size < 7) {
-    return 0;  // Error: invalid input
-  }
-  const uint8* decoder_configuration = configuration_record;
-  uint32 parameter_set_size_bytes = 0;
-
-  // We can skip the four first bytes as they're only profile information
-  decoder_configuration += 4;
-  // Fifth byte's two LSBs contain the interleaving field's size minus one
-  uint8 size_of_len_field = (*decoder_configuration & 0x3) + 1;
-  if (size_of_len_field != 1 && size_of_len_field != 2 &&
-      size_of_len_field != 4) {
-    return 0;  // Error: invalid input, NAL unit field len is not correct
-  }
-  decoder_configuration++;
-  // Sixth byte's five LSBs contain the number of SPSs
-  uint8 sps_count = *decoder_configuration & 0x1F;
-  decoder_configuration++;
-  // Then we have N * SPS's with two byte length field and actual SPS
-  while (sps_count-- > 0) {
-    if ((decoder_configuration - configuration_record) + 2 >
-         static_cast<int32>(configuration_record_size)) {
-      return 0;  // Error: ran out of data
-    }
-    uint16 sps_len = decoder_configuration[0] << 8 | decoder_configuration[1];
-    decoder_configuration += 2;
-    // write the SPS to output, always with zero byte + start code prefix
-    parameter_set_size_bytes += 1 + sizeof(kStartCodePrefix);
-    decoder_configuration += sps_len;
-    parameter_set_size_bytes += sps_len;
-  }
-  // Then we have the numner of pps in one byte
-  uint8 pps_count = *decoder_configuration;
-  decoder_configuration++;
-  // And finally, we have N * PPS with two byte length field and actual PPS
-  while (pps_count-- > 0) {
-    if ((decoder_configuration - configuration_record) + 2 >
-         static_cast<int32>(configuration_record_size)) {
-      return 0;  // Error: ran out of data
-    }
-    uint16 pps_len = decoder_configuration[0] << 8 | decoder_configuration[1];
-    decoder_configuration += 2;
-    // write the SPS to output, always with zero byte + start code prefix
-    parameter_set_size_bytes += 1 + sizeof(kStartCodePrefix);
-    decoder_configuration += pps_len;
-    parameter_set_size_bytes += pps_len;
-  }
-  // We're done processing the AVCDecoderConfigurationRecord,
-  // store the needed information for parsing actual payload
-  nal_unit_length_field_width_ = size_of_len_field;
-  configuration_processed_ = true;
-  return parameter_set_size_bytes;
-}
-
-uint32 H264BitstreamConverter::CalculateNeededOutputBufferSize(
-    const uint8* input,
-    uint32 input_size) const {
-  uint32 output_size = 0;
-  uint32 data_left = input_size;
-  bool first_nal_in_this_access_unit = first_nal_unit_in_access_unit_;
-
-  if (input == NULL || input_size == 0) {
-    return 0;  // Error: invalid input data
-  }
-  if (!configuration_processed_) {
-    return 0;  // Error: configuration not handled, we don't know nal unit width
-  }
-  CHECK(nal_unit_length_field_width_ == 1 ||
-        nal_unit_length_field_width_ == 2 ||
-        nal_unit_length_field_width_ == 4);
-
-  // Then add the needed size for the actual packet
-  while (data_left > 0) {
-    // Read the next NAL unit length from the input buffer
-    uint8 size_of_len_field;
-    uint32 nal_unit_length;
-    for (nal_unit_length = 0, size_of_len_field = nal_unit_length_field_width_;
-         size_of_len_field > 0;
-         input++, size_of_len_field--, data_left--) {
-      nal_unit_length <<= 8;
-      nal_unit_length |= *input;
-    }
-
-    if (nal_unit_length == 0) {
-      break;  // Signifies that no more data left in the buffer
-    } else if (nal_unit_length > data_left) {
-      return 0;  // Error: Not enough data for correct conversion
-    }
-    data_left -= nal_unit_length;
-
-    // five least significant bits of first NAL unit byte signify nal_unit_type
-    int nal_unit_type = *input & 0x1F;
-    if (first_nal_in_this_access_unit ||
-        IsAccessUnitBoundaryNal(nal_unit_type)) {
-      output_size += 1;  // Extra zero_byte for these nal units
-      first_nal_in_this_access_unit = false;
-    }
-    // Start code prefix
-    output_size += sizeof(kStartCodePrefix);
-    // Actual NAL unit size
-    output_size += nal_unit_length;
-    input += nal_unit_length;
-    // No need for trailing zero bits
-  }
-  return output_size;
-}
-
-bool H264BitstreamConverter::ConvertAVCDecoderConfigurationRecordToByteStream(
-    const uint8* input,
-    uint32 input_size,
-    uint8* output,
-    uint32* output_size) {
-  uint8* outscan = output;
-  // FFmpeg's AVCodecContext's extradata field contains the Decoder Specific
-  // Information from MP4 headers that contain the H.264 SPS and PPS members.
-  // ISO 14496-15 Chapter 5.2.4 AVCDecoderConfigurationRecord.
-  const uint8* decoder_configuration = input;
-  uint32 decoderconfiguration_size = input_size;
-  uint32 out_size = 0;
-
-  if (decoder_configuration == NULL || decoderconfiguration_size == 0) {
-    return 0;  // Error: input invalid
-  }
-
-  // We can skip the four first bytes as they're only profile information.
-  decoder_configuration += 4;
-  // Fifth byte's two LSBs contain the interleaving field's size minus one
-  uint8 size_of_len_field = (*decoder_configuration & 0x3) + 1;
-  if (size_of_len_field != 1 && size_of_len_field != 2 &&
-      size_of_len_field != 4) {
-    return 0;  // Error: invalid input, NAL unit field len is not correct
-  }
-  decoder_configuration++;
-  // Sixth byte's five LSBs contain the number of SPSs
-  uint8 sps_count = *decoder_configuration & 0x1F;
-  decoder_configuration++;
-  // Then we have N * SPS's with two byte length field and actual SPS
-  while (sps_count-- > 0) {
-    uint16 sps_len = decoder_configuration[0] << 8 |
-                     decoder_configuration[1];
-    decoder_configuration += 2;
-    if (out_size + 1 + sizeof(kStartCodePrefix) + sps_len >
-        *output_size) {
-      *output_size = 0;
-      return 0;  // too small output buffer;
-    }
-    // write the SPS to output, always with zero byte + start code prefix
-    *outscan = 0;  // zero byte
-    outscan += 1;
-    memcpy(outscan, kStartCodePrefix, sizeof(kStartCodePrefix));
-    outscan += sizeof(kStartCodePrefix);
-    memcpy(outscan, decoder_configuration, sps_len);
-    decoder_configuration += sps_len;
-    outscan += sps_len;
-    out_size += 1 + sizeof(kStartCodePrefix) + sps_len;
-  }
-  // Then we have the numner of pps in one byte
-  uint8 pps_count = *decoder_configuration;
-  decoder_configuration++;
-  // And finally, we have N * PPS with two byte length field and actual PPS
-  while (pps_count-- > 0) {
-    uint16 pps_len = decoder_configuration[0] << 8 | decoder_configuration[1];
-    decoder_configuration += 2;
-    if (out_size + 1 + sizeof(kStartCodePrefix) + pps_len >
-        *output_size) {
-      *output_size = 0;
-      return 0;  // too small output buffer;
-    }
-    // write the SPS to output, always with zero byte + start code prefix
-    *outscan = 0;  // zero byte
-    outscan += 1;
-    memcpy(outscan, kStartCodePrefix, sizeof(kStartCodePrefix));
-    outscan += sizeof(kStartCodePrefix);
-    memcpy(outscan, decoder_configuration, pps_len);
-    decoder_configuration += pps_len;
-    outscan += pps_len;
-    out_size += 1 + sizeof(kStartCodePrefix) + pps_len;
-  }
-  // We're done processing the AVCDecoderConfigurationRecord, store the needed
-  // information
-  nal_unit_length_field_width_ = size_of_len_field;
-  configuration_processed_ = true;
-  *output_size = out_size;
-  return true;
-}
-
-bool H264BitstreamConverter::ConvertNalUnitStreamToByteStream(
-    const uint8* input, uint32 input_size,
-    uint8* output, uint32* output_size) {
-  const uint8* inscan = input;  // We read the input from here progressively
-  uint8* outscan = output;  // We write the output to here progressively
-  uint32 data_left = input_size;
-
-  if (inscan == NULL || input_size == 0 ||
-      outscan == NULL || *output_size == 0) {
-    *output_size = 0;
-    return false;  // Error: invalid input
-  }
-
-  // NAL unit width should be known at this point
-  CHECK(nal_unit_length_field_width_ == 1 ||
-        nal_unit_length_field_width_ == 2 ||
-        nal_unit_length_field_width_ == 4);
-
-  // Do the actual conversion for the actual input packet
-  while (data_left > 0) {
-    uint8 i;
-    uint32 nal_unit_length;
-
-    // Read the next NAL unit length from the input buffer by scanning
-    // the input stream with the specific length field width
-    for (nal_unit_length = 0, i = nal_unit_length_field_width_;
-         i > 0 && data_left > 0;
-         inscan++, i--, data_left--) {
-      nal_unit_length <<= 8;
-      nal_unit_length |= *inscan;
-    }
-
-    if (nal_unit_length == 0) {
-      break;  // Successful conversion, end of buffer
-    } else if (nal_unit_length > data_left) {
-      *output_size = 0;
-      return false;  // Error: not enough data for correct conversion
-    }
-
-    uint32 start_code_len;
-    first_nal_unit_in_access_unit_ ?
-        start_code_len = sizeof(kStartCodePrefix) + 1 :
-        start_code_len = sizeof(kStartCodePrefix);
-    if (static_cast<uint32>(outscan - output) +
-        start_code_len + nal_unit_length > *output_size) {
-      *output_size = 0;
-      return false;  // Error: too small output buffer
-    }
-
-    // Five least significant bits of first NAL unit byte signify
-    // nal_unit_type.
-    int nal_unit_type = *inscan & 0x1F;
-
-    // Check if this packet marks access unit boundary by checking the
-    // packet type.
-    if (IsAccessUnitBoundaryNal(nal_unit_type)) {
-      first_nal_unit_in_access_unit_ = true;
-    }
-
-    // Write extra zero-byte before start code prefix if this packet
-    // signals next access unit.
-    if (first_nal_unit_in_access_unit_) {
-      *outscan = 0;
-      outscan++;
-      first_nal_unit_in_access_unit_ = false;
-    }
-
-    // No need to write leading zero bits.
-    // Write start-code prefix.
-    memcpy(outscan, kStartCodePrefix, sizeof(kStartCodePrefix));
-    outscan += sizeof(kStartCodePrefix);
-    // Then write the actual NAL unit from the input buffer.
-    memcpy(outscan, inscan, nal_unit_length);
-    inscan += nal_unit_length;
-    data_left -= nal_unit_length;
-    outscan += nal_unit_length;
-    // No need for trailing zero bits.
-  }
-  // Successful conversion, output the freshly allocated bitstream buffer.
-  *output_size = static_cast<uint32>(outscan - output);
-  return true;
-}
-
-}  // namespace media