2 Copyright (C) 2012-2020 Carl Hetherington <cth@carlh.net>
4 This file is part of libdcp.
6 libdcp is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 libdcp is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with libdcp. If not, see <http://www.gnu.org/licenses/>.
19 In addition, as a special exception, the copyright holders give
20 permission to link the code of portions of this program with the
21 OpenSSL library under certain conditions as described in each
22 individual source file, and distribute linked combinations
25 You must obey the GNU General Public License in all respects
26 for all of the code used other than OpenSSL. If you modify
27 file(s) with this exception, you may extend this exception to your
28 version of the file(s), but you are not obligated to do so. If you
29 do not wish to do so, delete this exception statement from your
30 version. If you delete this exception statement from all source
31 files in the program, then also delete it here.
34 #include "bitstream.h"
35 #include "sound_asset_writer.h"
36 #include "sound_asset.h"
37 #include "exceptions.h"
38 #include "dcp_assert.h"
39 #include "compose.hpp"
40 #include "crypto_context.h"
41 #include <asdcp/AS_DCP.h>
42 #include <asdcp/Metadata.h>
43 #include <boost/foreach.hpp>
54 struct SoundAssetWriter::ASDCPState
56 ASDCP::PCM::MXFWriter mxf_writer;
57 ASDCP::PCM::FrameBuffer frame_buffer;
58 ASDCP::WriterInfo writer_info;
59 ASDCP::PCM::AudioDescriptor desc;
62 SoundAssetWriter::SoundAssetWriter (SoundAsset* asset, boost::filesystem::path file, vector<Channel> active_channels, bool sync)
63 : AssetWriter (asset, file)
64 , _state (new SoundAssetWriter::ASDCPState)
66 , _frame_buffer_offset (0)
69 , _active_channels (active_channels)
71 DCP_ASSERT (!_sync || _asset->channels() >= 14);
72 DCP_ASSERT (!_sync || _asset->standard() == SMPTE);
74 /* Derived from ASDCP::Wav::SimpleWaveHeader::FillADesc */
75 _state->desc.EditRate = ASDCP::Rational (_asset->edit_rate().numerator, _asset->edit_rate().denominator);
76 _state->desc.AudioSamplingRate = ASDCP::Rational (_asset->sampling_rate(), 1);
77 _state->desc.Locked = 0;
78 _state->desc.ChannelCount = _asset->channels ();
79 _state->desc.QuantizationBits = 24;
80 _state->desc.BlockAlign = 3 * _asset->channels();
81 _state->desc.AvgBps = _asset->sampling_rate() * _state->desc.BlockAlign;
82 _state->desc.LinkedTrackID = 0;
83 if (asset->standard() == INTEROP) {
84 _state->desc.ChannelFormat = ASDCP::PCM::CF_NONE;
86 /* Just use WTF ("wild track format") for SMPTE for now; searches suggest that this
87 uses the same assignment as Interop.
89 _state->desc.ChannelFormat = ASDCP::PCM::CF_CFG_4;
92 /* I'm fairly sure this is not necessary, as ContainerDuration is written
93 in ASDCP's WriteMXFFooter, but it stops a valgrind warning.
95 _state->desc.ContainerDuration = 0;
97 _state->frame_buffer.Capacity (ASDCP::PCM::CalcFrameBufferSize (_state->desc));
98 _state->frame_buffer.Size (ASDCP::PCM::CalcFrameBufferSize (_state->desc));
99 memset (_state->frame_buffer.Data(), 0, _state->frame_buffer.Capacity());
101 _asset->fill_writer_info (&_state->writer_info, _asset->id());
104 _fsk.set_data (create_sync_packets());
110 SoundAssetWriter::start ()
112 Kumu::Result_t r = _state->mxf_writer.OpenWrite (_file.string().c_str(), _state->writer_info, _state->desc);
113 if (ASDCP_FAILURE (r)) {
114 boost::throw_exception (FileError ("could not open audio MXF for writing", _file.string(), r));
117 if (_asset->standard() == dcp::SMPTE && !_active_channels.empty()) {
119 ASDCP::MXF::WaveAudioDescriptor* essence_descriptor = 0;
120 _state->mxf_writer.OP1aHeader().GetMDObjectByType(
121 asdcp_smpte_dict->ul(ASDCP::MDD_WaveAudioDescriptor), reinterpret_cast<ASDCP::MXF::InterchangeObject**>(&essence_descriptor)
123 DCP_ASSERT (essence_descriptor);
124 essence_descriptor->ChannelAssignment = asdcp_smpte_dict->ul(ASDCP::MDD_DCAudioChannelCfg_MCA);
126 ASDCP::MXF::SoundfieldGroupLabelSubDescriptor* soundfield = new ASDCP::MXF::SoundfieldGroupLabelSubDescriptor(asdcp_smpte_dict);
127 GenRandomValue (soundfield->MCALinkID);
128 soundfield->RFC5646SpokenLanguage = _asset->language();
130 const MCASoundField field = _asset->channels() > 10 ? SEVEN_POINT_ONE : FIVE_POINT_ONE;
132 if (field == SEVEN_POINT_ONE) {
133 soundfield->MCATagSymbol = "sg71";
134 soundfield->MCATagName = "7.1DS";
135 soundfield->MCALabelDictionaryID = asdcp_smpte_dict->ul(ASDCP::MDD_DCAudioSoundfield_71);
137 soundfield->MCATagSymbol = "sg51";
138 soundfield->MCATagName = "5.1";
139 soundfield->MCALabelDictionaryID = asdcp_smpte_dict->ul(ASDCP::MDD_DCAudioSoundfield_51);
142 _state->mxf_writer.OP1aHeader().AddChildObject(soundfield);
143 essence_descriptor->SubDescriptors.push_back(soundfield->InstanceUID);
145 BOOST_FOREACH (Channel i, _active_channels) {
146 ASDCP::MXF::AudioChannelLabelSubDescriptor* channel = new ASDCP::MXF::AudioChannelLabelSubDescriptor(asdcp_smpte_dict);
147 GenRandomValue (channel->MCALinkID);
148 channel->SoundfieldGroupLinkID = soundfield->MCALinkID;
149 channel->MCAChannelID = static_cast<int>(i) + 1;
150 channel->MCATagSymbol = "ch" + channel_to_mca_id(i, field);
151 channel->MCATagName = channel_to_mca_name(i, field);
152 channel->RFC5646SpokenLanguage = _asset->language();
153 channel->MCALabelDictionaryID = channel_to_mca_universal_label(i, field, asdcp_smpte_dict);
154 _state->mxf_writer.OP1aHeader().AddChildObject(channel);
155 essence_descriptor->SubDescriptors.push_back(channel->InstanceUID);
159 _asset->set_file (_file);
164 /** @param data Pointer an array of float pointers, one for each channel.
165 * @param frames Number of frames i.e. number of floats that are given for each channel.
168 SoundAssetWriter::write (float const * const * data, int frames)
170 DCP_ASSERT (!_finalized);
171 DCP_ASSERT (frames > 0);
173 static float const clip = 1.0f - (1.0f / pow (2, 23));
179 int const ch = _asset->channels ();
181 for (int i = 0; i < frames; ++i) {
183 byte_t* out = _state->frame_buffer.Data() + _frame_buffer_offset;
185 /* Write one sample per channel */
186 for (int j = 0; j < ch; ++j) {
188 if (j == 13 && _sync) {
191 /* Convert sample to 24-bit int, clipping if necessary. */
192 float x = data[j][i];
195 } else if (x < -clip) {
201 *out++ = (s & 0xff00) >> 8;
202 *out++ = (s & 0xff0000) >> 16;
204 _frame_buffer_offset += 3 * ch;
206 DCP_ASSERT (_frame_buffer_offset <= int (_state->frame_buffer.Capacity()));
208 /* Finish the MXF frame if required */
209 if (_frame_buffer_offset == int (_state->frame_buffer.Capacity())) {
210 write_current_frame ();
211 _frame_buffer_offset = 0;
212 memset (_state->frame_buffer.Data(), 0, _state->frame_buffer.Capacity());
218 SoundAssetWriter::write_current_frame ()
220 ASDCP::Result_t const r = _state->mxf_writer.WriteFrame (_state->frame_buffer, _crypto_context->context(), _crypto_context->hmac());
221 if (ASDCP_FAILURE (r)) {
222 boost::throw_exception (MiscError (String::compose ("could not write audio MXF frame (%1)", int (r))));
228 /* We need a new set of sync packets for this frame */
229 _fsk.set_data (create_sync_packets());
234 SoundAssetWriter::finalize ()
236 if (_frame_buffer_offset > 0) {
237 write_current_frame ();
241 ASDCP::Result_t const r = _state->mxf_writer.Finalize();
242 if (ASDCP_FAILURE(r)) {
243 boost::throw_exception (MiscError (String::compose ("could not finalise audio MXF (%1)", int(r))));
247 _asset->_intrinsic_duration = _frames_written;
248 return AssetWriter::finalize ();
252 /** Calculate and return the sync packets required for this edit unit (aka "frame") */
254 SoundAssetWriter::create_sync_packets ()
256 /* Parts of this code assumes 48kHz */
257 DCP_ASSERT (_asset->sampling_rate() == 48000);
259 /* Encoding of edit rate */
260 int edit_rate_code = 0;
261 /* How many 0 bits are used to pad the end of the packet */
262 int remaining_bits = 0;
263 /* How many packets in this edit unit (i.e. "frame") */
265 Fraction const edit_rate = _asset->edit_rate ();
266 if (edit_rate == Fraction(24, 1)) {
270 } else if (edit_rate == Fraction(25, 1)) {
274 } else if (edit_rate == Fraction(30, 1)) {
278 } else if (edit_rate == Fraction(48, 1)) {
282 } else if (edit_rate == Fraction(50, 1)) {
286 } else if (edit_rate == Fraction(60, 1)) {
290 } else if (edit_rate == Fraction(96, 1)) {
294 } else if (edit_rate == Fraction(100, 1)) {
298 } else if (edit_rate == Fraction(120, 1)) {
307 DCP_ASSERT (id.DecodeHex(_asset->id().c_str()));
309 for (int i = 0; i < packets; ++i) {
310 bs.write_from_byte (0x4d);
311 bs.write_from_byte (0x56);
312 bs.start_crc (0x1021);
313 bs.write_from_byte (edit_rate_code, 4);
314 bs.write_from_byte (0, 2);
315 bs.write_from_byte (_sync_packet, 2);
316 bs.write_from_byte (id.Value()[i * 4 + 0]);
317 bs.write_from_byte (id.Value()[i * 4 + 1]);
318 bs.write_from_byte (id.Value()[i * 4 + 2]);
319 bs.write_from_byte (id.Value()[i * 4 + 3]);
320 bs.write_from_word (_frames_written, 24);
322 bs.write_from_byte (0, 4);
323 bs.write_from_word (0, remaining_bits);
326 if (_sync_packet == 4) {