src/decoders/opusfile.cpp

   1
   2 #include "opusfile.hpp"
   3
   4 #include <stdexcept>
   5 #include <iostream>
   6 #include <limits>
   7
   8 #include "buffer.h"
   9
  10 #include "opusfile.h"
  11
  12 namespace alure
  13 {
  14
  15 static int read(void *user_data, unsigned char *ptr, int size)
  16 {
  17     std::istream *stream = static_cast<std::istream*>(user_data);
  18     stream->clear();
  19
  20     if(size < 0 || !stream->read(reinterpret_cast<char*>(ptr), size))
  21         return -1;
  22     return stream->gcount();
  23 }
  24
  25 static int seek(void *user_data, opus_int64 offset, int whence)
  26 {
  27     std::istream *stream = static_cast<std::istream*>(user_data);
  28     stream->clear();
  29
  30     if(whence == SEEK_CUR)
  31         stream->seekg(offset, std::ios_base::cur);
  32     else if(whence == SEEK_SET)
  33         stream->seekg(offset, std::ios_base::beg);
  34     else if(whence == SEEK_END)
  35         stream->seekg(offset, std::ios_base::end);
  36     else
  37         return -1;
  38
  39     return stream->good() ? 0 : -1;
  40 }
  41
  42 static opus_int64 tell(void *user_data)
  43 {
  44     std::istream *stream = static_cast<std::istream*>(user_data);
  45     stream->clear();
  46     return stream->tellg();
  47 }
  48
  49
  50 template<typename T> struct OggTypeInfo { };
  51 template<>
  52 struct OggTypeInfo<ogg_int16_t>
  53 {
  54     template<typename ...Args>
  55     static int read(Args&& ...args)
  56     { return op_read(std::forward<Args>(args)...); }
  57 };
  58 template<>
  59 struct OggTypeInfo<float>
  60 {
  61     template<typename ...Args>
  62     static int read(Args&& ...args)
  63     { return op_read_float(std::forward<Args>(args)...); }
  64 };
  65
  66 class OpusFileDecoder final : public Decoder {
  67     UniquePtr<std::istream> mFile;
  68
  69     OggOpusFile *mOggFile;
  70     int mOggBitstream;
  71
  72     ChannelConfig mChannelConfig;
  73     SampleType mSampleType;
  74
  75     template<typename T>
  76     ALuint do_read(T *ptr, ALuint count) noexcept
  77     {
  78         ALuint total = 0;
  79         T *samples = ptr;
  80         int num_chans = FramesToBytes(1, mChannelConfig, SampleType::UInt8);
  81         while(total < count)
  82         {
  83             if(num_chans != op_head(mOggFile, -1)->channel_count)
  84                 break;
  85             int len = (count-total) * num_chans;
  86
  87             long got = OggTypeInfo<T>::read(mOggFile, samples, len, &mOggBitstream);
  88             if(got <= 0) break;
  89
  90             samples += got*num_chans;
  91             total += got;
  92         }
  93
  94         // 1, 2, and 4 channel files decode into the same channel order as
  95         // OpenAL, however 6 (5.1), 7 (6.1), and 8 (7.1) channel files need to be
  96         // re-ordered.
  97         if(mChannelConfig == ChannelConfig::X51)
  98         {
  99             samples = ptr;
 100             for(ALuint i = 0;i < total;++i)
 101             {
 102                 // OpenAL : FL, FR, FC, LFE, RL, RR
 103                 // Opus   : FL, FC, FR,  RL, RR, LFE
 104                 std::swap(samples[i*6 + 1], samples[i*6 + 2]);
 105                 std::swap(samples[i*6 + 3], samples[i*6 + 5]);
 106                 std::swap(samples[i*6 + 4], samples[i*6 + 5]);
 107             }
 108         }
 109         else if(mChannelConfig == ChannelConfig::X61)
 110         {
 111             samples = ptr;
 112             for(ALuint i = 0;i < total;++i)
 113             {
 114                 // OpenAL : FL, FR, FC, LFE, RC, SL, SR
 115                 // Opus   : FL, FC, FR,  SL, SR, RC, LFE
 116                 std::swap(samples[i*7 + 1], samples[i*7 + 2]);
 117                 std::swap(samples[i*7 + 3], samples[i*7 + 6]);
 118                 std::swap(samples[i*7 + 4], samples[i*7 + 5]);
 119                 std::swap(samples[i*7 + 5], samples[i*7 + 6]);
 120             }
 121         }
 122         else if(mChannelConfig == ChannelConfig::X71)
 123         {
 124             samples = ptr;
 125             for(ALuint i = 0;i < total;++i)
 126             {
 127                 // OpenAL : FL, FR, FC, LFE, RL, RR, SL, SR
 128                 // Opus   : FL, FC, FR,  SL, SR, RL, RR, LFE
 129                 std::swap(samples[i*8 + 1], samples[i*8 + 2]);
 130                 std::swap(samples[i*8 + 3], samples[i*8 + 7]);
 131                 std::swap(samples[i*8 + 4], samples[i*8 + 5]);
 132                 std::swap(samples[i*8 + 5], samples[i*8 + 6]);
 133                 std::swap(samples[i*8 + 6], samples[i*8 + 7]);
 134             }
 135         }
 136
 137         return total;
 138     }
 139
 140 public:
 141     OpusFileDecoder(UniquePtr<std::istream> file, OggOpusFile *oggfile, ChannelConfig sconfig, SampleType stype) noexcept
 142       : mFile(std::move(file)), mOggFile(oggfile), mOggBitstream(0), mChannelConfig(sconfig), mSampleType(stype)
 143     { }
 144     ~OpusFileDecoder() override;
 145
 146     ALuint getFrequency() const noexcept override;
 147     ChannelConfig getChannelConfig() const noexcept override;
 148     SampleType getSampleType() const noexcept override;
 149
 150     uint64_t getLength() const noexcept override;
 151     bool seek(uint64_t pos) noexcept override;
 152
 153     std::pair<uint64_t,uint64_t> getLoopPoints() const noexcept override;
 154
 155     ALuint read(ALvoid *ptr, ALuint count) noexcept override;
 156 };
 157
 158 OpusFileDecoder::~OpusFileDecoder()
 159 {
 160     op_free(mOggFile);
 161 }
 162
 163
 164 ALuint OpusFileDecoder::getFrequency() const noexcept
 165 {
 166     // libopusfile always decodes to 48khz.
 167     return 48000;
 168 }
 169
 170 ChannelConfig OpusFileDecoder::getChannelConfig() const noexcept
 171 {
 172     return mChannelConfig;
 173 }
 174
 175 SampleType OpusFileDecoder::getSampleType() const noexcept
 176 {
 177     return mSampleType;
 178 }
 179
 180
 181 uint64_t OpusFileDecoder::getLength() const noexcept
 182 {
 183     ogg_int64_t len = op_pcm_total(mOggFile, -1);
 184     return std::max<ogg_int64_t>(len, 0);
 185 }
 186
 187 bool OpusFileDecoder::seek(uint64_t pos) noexcept
 188 {
 189     return op_pcm_seek(mOggFile, pos) == 0;
 190 }
 191
 192 std::pair<uint64_t,uint64_t> OpusFileDecoder::getLoopPoints() const noexcept
 193 {
 194     return std::make_pair(0, std::numeric_limits<uint64_t>::max());
 195 }
 196
 197 ALuint OpusFileDecoder::read(ALvoid *ptr, ALuint count) noexcept
 198 {
 199     if(mSampleType == SampleType::Float32)
 200         return do_read<float>(reinterpret_cast<float*>(ptr), count);
 201     return do_read<ogg_int16_t>(reinterpret_cast<ogg_int16_t*>(ptr), count);
 202 }
 203
 204
 205 SharedPtr<Decoder> OpusFileDecoderFactory::createDecoder(UniquePtr<std::istream> &file) noexcept
 206 {
 207     static const OpusFileCallbacks streamIO = {
 208         read, seek, tell, nullptr
 209     };
 210
 211     OggOpusFile *oggfile = op_open_callbacks(file.get(), &streamIO, nullptr, 0, nullptr);
 212     if(!oggfile) return nullptr;
 213
 214     std::pair<uint64_t,uint64_t> loop_points = { 0, std::numeric_limits<uint64_t>::max() };
 215     if(const OpusTags *tags = op_tags(oggfile, -1))
 216     {
 217         for(int i = 0;i < tags->comments;i++)
 218         {
 219             auto seppos = StringView(
 220                 tags->user_comments[i], tags->comment_lengths[i]
 221             ).find_first_of('=');
 222             if(seppos == StringView::npos) continue;
 223
 224             StringView key(tags->user_comments[i], seppos);
 225             StringView val(tags->user_comments[i]+seppos+1, tags->comment_lengths[i]-(seppos+1));
 226
 227             // RPG Maker seems to recognize LOOPSTART and LOOPLENGTH for loop
 228             // points in a Vorbis comment. ZDoom recognizes LOOP_START and
 229             // LOOP_END. We can recognize both.
 230             if(key == "LOOP_START" || key == "LOOPSTART")
 231             {
 232                 auto pt = parse_timeval(val, 48000.0);
 233                 if(pt.index() == 1) loop_points.first = std::get<1>(pt);
 234                 continue;
 235             }
 236
 237             if(key == "LOOP_END")
 238             {
 239                 auto pt = parse_timeval(val, 48000.0);
 240                 if(pt.index() == 1) loop_points.second = std::get<1>(pt);
 241                 continue;
 242             }
 243
 244             if(key == "LOOPLENGTH")
 245             {
 246                 auto pt = parse_timeval(val, 48000.0);
 247                 if(pt.index() == 1)
 248                     loop_points.second = loop_points.first + std::get<1>(pt);
 249                 continue;
 250             }
 251         }
 252     }
 253
 254     int num_chans = op_head(oggfile, -1)->channel_count;
 255     ChannelConfig channels = ChannelConfig::Mono;
 256     if(num_chans == 1)
 257         channels = ChannelConfig::Mono;
 258     else if(num_chans == 2)
 259         channels = ChannelConfig::Stereo;
 260     else if(num_chans == 4)
 261         channels = ChannelConfig::Quad;
 262     else if(num_chans == 6)
 263         channels = ChannelConfig::X51;
 264     else if(num_chans == 7)
 265         channels = ChannelConfig::X61;
 266     else if(num_chans == 8)
 267         channels = ChannelConfig::X71;
 268     else
 269     {
 270         op_free(oggfile);
 271         return nullptr;
 272     }
 273
 274     if(Context::GetCurrent().isSupported(channels, SampleType::Float32))
 275         return MakeShared<OpusFileDecoder>(std::move(file), oggfile, channels, SampleType::Float32);
 276     return MakeShared<OpusFileDecoder>(std::move(file), oggfile, channels, SampleType::Int16);
 277 }
 278
 279 }