| public ReadBitsToByte ( byte count = 8 ) : byte | ||
| count | byte | |
| return | byte | |
public bool Init(Stream pBuffer, int length)
{
Clear();
var oldPosition = pBuffer.Position;
if (length < 2)
{
Logger.FATAL("Invalid length:{0}", length);
return false;
}
var bitReader = new BitReader(pBuffer);
_audioObjectType = bitReader.ReadBitsToByte(5);
if ((_audioObjectType != 1)
&& (_audioObjectType != 2)
&& (_audioObjectType != 3)
&& (_audioObjectType != 4)
&& (_audioObjectType != 6)
&& (_audioObjectType != 17)
&& (_audioObjectType != 19)
&& (_audioObjectType != 20)
&& (_audioObjectType != 23)
&& (_audioObjectType != 39))
{
Logger.FATAL("Invalid _audioObjectType: {0}", _audioObjectType);
return false;
}
//3. Read the sample rate index
_sampleRateIndex = bitReader.ReadBitsToByte(4);
if ((_sampleRateIndex == 13)
|| (_sampleRateIndex == 14))
{
Logger.FATAL("Invalid sample rate: {0}", _sampleRateIndex);
return false;
}
if (_sampleRateIndex == 15)
{
if (length < 5)
{
Logger.FATAL("Invalid length:{0}", length);
return false;
}
_sampleRate = (uint)bitReader.ReadBitsToInt(24);
}
else
{
var rates = new uint[]{
96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050, 16000,
12000, 11025, 8000, 7350
};
_sampleRate = rates[_sampleRateIndex];
}
//4. read the channel configuration index
_channelConfigurationIndex = bitReader.ReadBitsToByte(4);
if ((_channelConfigurationIndex == 0)
|| (_channelConfigurationIndex >= 8))
{
Logger.FATAL("Invalid _channelConfigurationIndex: {0}", _channelConfigurationIndex);
return false;
}
pBuffer.Position = oldPosition;
_pAAC = new byte[length];
pBuffer.Read(_pAAC, 0, length);
_aacLength = (uint) length;
return true;
}
private bool ReadSPSVUI(BitReader spsReader, Variant v)
{
//E.1.1 VUI parameters syntax
//14496-10.pdf 267/280
v["aspect_ratio_info_present_flag"] = spsReader.ReadBool();
if (v["aspect_ratio_info_present_flag"])
{
v["aspect_ratio_idc"] = spsReader.ReadBitsToByte();
if ((byte)v["aspect_ratio_idc"] == 255)
{
v["sar_width"] = (ushort)spsReader.ReadBitsToShort();
v["sar_height"] = (ushort)spsReader.ReadBitsToShort();
}
}
v["overscan_info_present_flag"] = spsReader.ReadBool();
if (v["overscan_info_present_flag"])
v["overscan_appropriate_flag"] = spsReader.ReadBool();
v["video_signal_type_present_flag"] = spsReader.ReadBool();
if (v["video_signal_type_present_flag"])
{
v["video_format"] = spsReader.ReadBitsToByte(3);
v["video_full_range_flag"] = spsReader.ReadBool();
v["colour_description_present_flag"] = spsReader.ReadBool();
if (v["colour_description_present_flag"])
{
v["colour_primaries"] = spsReader.ReadBitsToByte();
v["transfer_characteristics"] = spsReader.ReadBitsToByte();
v["matrix_coefficients"] = spsReader.ReadBitsToByte();
}
}
v["chromloc_info_present_flag"] = spsReader.ReadBool();
if (v["chromloc_info_present_flag"])
{
v["chromsample_loc_type_top_field"] = spsReader.ReadExpGolomb("chromsample_loc_type_top_field");
v["chromsample_loc_type_bottom_field"] = spsReader.ReadExpGolomb("chromsample_loc_type_bottom_field");
}
v["timing_info_present_flag"] = spsReader.ReadBool();
if (v["timing_info_present_flag"])
{
v["num_units_in_tick"] = spsReader.ReadBitsToInt();
v["time_scale"] = spsReader.ReadBitsToInt();
v["fixed_frame_rate_flag"] = spsReader.ReadBool();
}
v["nal_hrd_parameters_present_flag"] = spsReader.ReadBool();
if (v["nal_hrd_parameters_present_flag"])
{
if (!ReadSPSVUIHRD(spsReader, v["nal_hrd"] = Variant.Get()))
{
Logger.FATAL("Unable to read VUIHRD");
return false;
}
}
v["vcl_hrd_parameters_present_flag"] = spsReader.ReadBool();
if (v["vcl_hrd_parameters_present_flag"])
{
if (!ReadSPSVUIHRD(spsReader, v["vcl_hrd"] = Variant.Get()))
{
Logger.FATAL("Unable to read VUIHRD");
return false;
}
}
if (v["nal_hrd_parameters_present_flag"]
|| v["vcl_hrd_parameters_present_flag"])
v["low_delay_hrd_flag"] = spsReader.ReadBool();
v["pic_struct_present_flag"] = spsReader.ReadBool();
v["bitstream_restriction_flag"] = spsReader.ReadBool();
if (v["bitstream_restriction_flag"])
{
v["motion_vectors_over_pic_boundaries_flag"] = spsReader.ReadBool();
v["max_bytes_per_pic_denom"] = spsReader.ReadExpGolomb("max_bytes_per_pic_denom");
v["max_bits_per_mb_denom"] = spsReader.ReadExpGolomb("max_bits_per_mb_denom");
v["log2_max_mv_length_horizontal"] = spsReader.ReadExpGolomb("log2_max_mv_length_horizontal");
v["log2_max_mv_length_vertical"] = spsReader.ReadExpGolomb("log2_max_mv_length_vertical");
v["num_reorder_frames"] = spsReader.ReadExpGolomb("num_reorder_frames");
v["max_dec_frame_buffering"] = spsReader.ReadExpGolomb("max_dec_frame_buffering");
}
return true;
}
private bool ReadSPSVUIHRD(BitReader spsReader, Variant v)
{
//E.1.2 HRD parameters syntax
//14496-10.pdf 268/280
v["cpb_cnt_minus1"] = spsReader.ReadExpGolomb("cpb_cnt_minus1");
v["bit_rate_scale"] = spsReader.ReadBitsToByte(4);
v["cpb_size_scale"] = spsReader.ReadBitsToByte(4);
v["bit_rate_value_minus1"] = Variant.Get();
v["cpb_size_value_minus1"] = Variant.Get();
v["cbr_flag"] = Variant.Get();
for (ulong i = 0; i <= v["cpb_cnt_minus1"]; i++)
{
var val = spsReader.ReadExpGolomb("bit_rate_value_minus1");
v["bit_rate_value_minus1"].Add(val);
val = spsReader.ReadExpGolomb("cpb_size_value_minus1");
v["cpb_size_value_minus1"].Add(val);
if (spsReader.AvailableBits < 1)
{
Logger.FATAL("not enough data");
return false;
}
v["cbr_flag"].Add(spsReader.ReadBool());
}
v["initial_cpb_removal_delay_length_minus1"] = spsReader.ReadBitsToByte(5);
v["cpb_removal_delay_length_minus1"] = spsReader.ReadBitsToByte(5);
v["dpb_output_delay_length_minus1"] = spsReader.ReadBitsToByte(5);
v["time_offset_length"] = spsReader.ReadBitsToByte(5);
return true;
}
private bool ReadSPS(BitReader spsReader, Variant spsInfo)
{
//7.3.2.1 Sequence parameter set RBSP syntax
//14496-10.pdf 43/280
spsInfo["profile_idc"] = spsReader.ReadBitsToByte();
spsInfo["constraint_set0_flag"] = spsReader.ReadBool();
spsInfo["constraint_set1_flag"] = spsReader.ReadBool();
spsInfo["constraint_set2_flag"] = spsReader.ReadBool();
spsInfo["reserved_zero_5bits"] = spsReader.ReadBitsToByte(5);
spsInfo["level_idc"] = spsReader.ReadBitsToByte();
spsInfo["seq_parameter_set_id"] = spsReader.ReadExpGolomb("seq_parameter_set_id");
if (spsInfo["profile_idc"] >= 100)
{
spsInfo["chromformat_idc"] = spsReader.ReadExpGolomb("chromformat_idc");
if (spsInfo["chromformat_idc"] == 3) spsInfo["residual_colour_transform_flag"] = spsReader.ReadBool();
spsInfo["bit_depth_lumminus8"] = spsReader.ReadExpGolomb("bit_depth_lumminus8");
spsInfo["bit_depth_chromminus8"] = spsReader.ReadExpGolomb("bit_depth_chromminus8");
spsInfo["qpprime_y_zero_transform_bypass_flag"] = spsReader.ReadBool();
spsInfo["seq_scaling_matrix_present_flag"] = spsReader.ReadBool();
if (spsInfo["seq_scaling_matrix_present_flag"])
{
for (byte i = 0; i < 8; i++)
{
if (spsReader.AvailableBits < 1)
{
Logger.FATAL("unable to read seq_scaling_list_present_flag not enought bits ");
return false;
}
if (spsReader.ReadBool())
{
if (i < 6)
{
if (scaling_list(spsReader, 16)) continue;
Logger.FATAL("scaling_list failed");
return false;
}
if (scaling_list(spsReader, 64)) continue;
Logger.FATAL("scaling_list failed");
return false;
}
}
}
}
spsInfo["log2_max_frame_num_minus4"] = spsReader.ReadExpGolomb("log2_max_frame_num_minus4");
spsInfo["pic_order_cnt_type"] = spsReader.ReadExpGolomb("pic_order_cnt_type");
if ((ulong)spsInfo["pic_order_cnt_type"] == 0)
{
spsInfo["log2_max_pic_order_cnt_lsb_minus4"] = spsReader.ReadExpGolomb("log2_max_pic_order_cnt_lsb_minus4");
}
else if ((ulong)spsInfo["pic_order_cnt_type"] == 1)
{
spsInfo["deltpic_order_always_zero_flag"] = spsReader.ReadBool();
spsInfo["offset_for_non_ref_pic"] = (long)spsReader.ReadExpGolomb("offset_for_non_ref_pic");
spsInfo["offset_for_top_to_bottom_field"] = (long)spsReader.ReadExpGolomb("offset_for_top_to_bottom_field");
spsInfo["num_ref_frames_in_pic_order_cnt_cycle"] = spsReader.ReadExpGolomb("num_ref_frames_in_pic_order_cnt_cycle");
for (ulong i = 0; i < (ulong)spsInfo["num_ref_frames_in_pic_order_cnt_cycle"]; i++)
{
var val = spsReader.ReadExpGolomb("offset_for_ref_frame value");
spsInfo["offset_for_ref_frame"].Add((long)val);
}
}
spsInfo["num_ref_frames"] = spsReader.ReadExpGolomb("num_ref_frames");
spsInfo["gaps_in_frame_num_value_allowed_flag"] = spsReader.ReadBool();
spsInfo["pic_width_in_mbs_minus1"] = spsReader.ReadExpGolomb("pic_width_in_mbs_minus1");
spsInfo["pic_height_in_map_units_minus1"] = spsReader.ReadExpGolomb("pic_height_in_map_units_minus1");
spsInfo["frame_mbs_only_flag"] = spsReader.ReadBool();
if (!spsInfo["frame_mbs_only_flag"])
spsInfo["mb_adaptive_frame_field_flag"] = spsReader.ReadBool();
spsInfo["direct_8x8_inference_flag"] = spsReader.ReadBool();
spsInfo["frame_cropping_flag"] = spsReader.ReadBool();
if (spsInfo["frame_cropping_flag"])
{
spsInfo["frame_crop_left_offset"] = spsReader.ReadExpGolomb("frame_crop_left_offset");
spsInfo["frame_crop_right_offset"] = spsReader.ReadExpGolomb("frame_crop_right_offset");
spsInfo["frame_crop_top_offset"] = spsReader.ReadExpGolomb("frame_crop_top_offset");
spsInfo["frame_crop_bottom_offset"] = spsReader.ReadExpGolomb("frame_crop_bottom_offset");
}
spsInfo["vui_parameters_present_flag"] = spsReader.ReadBool();
if (!spsInfo["vui_parameters_present_flag"]) return true;
if (ReadSPSVUI(spsReader, spsInfo["vui_parameters"]= Variant.Get())) return true;
Logger.FATAL("Unable to read VUI");
return false;
}
