ogg decoder

src/audio/audio.cpp

@@ -7,6 +7,7 @@
 #include "NoAudio.h"
 
 #include "../coders/wav.h"
+#include "../coders/ogg.h"
 
 namespace audio {
     static speakerid_t nextId = 1;
@@ -30,7 +31,9 @@ PCM* audio::loadPCM(const fs::path& file, bool headerOnly) {
     std::string ext = file.extension().u8string();
     if (ext == ".wav" || ext == ".WAV") {
         return wav::load_pcm(file, headerOnly);
-    } // TODO: OGG support
+    } else if (ext == ".ogg" || ext == ".OGG") {
+        return ogg::load_pcm(file, headerOnly);
+    }
     throw std::runtime_error("unsupported audio format");
 }
 

src/coders/ogg.cpp

@@ -0,0 +1,56 @@
+#include "ogg.h"
+
+#include <iostream>
+#include <vorbis/codec.h>
+#include <vorbis/vorbisfile.h>
+
+#include "../audio/audio.h"
+#include "../typedefs.h"
+
+static inline const char* vorbis_error_message(int code) {
+    switch (code) {
+        case 0: return "no error";
+        case OV_EREAD: return "a read from media returned an error";
+        case OV_ENOTVORBIS: return "bitstream does not contain any Vorbis data";
+        case OV_EVERSION: return "vorbis version mismatch";
+        case OV_EBADHEADER: return "invalid Vorbis bitstream header";
+        case OV_EFAULT: return "internal logic fault";
+        default:
+            return "unknown";
+    }
+}
+
+audio::PCM* ogg::load_pcm(const std::filesystem::path& file, bool headerOnly) {
+    OggVorbis_File vf;
+    int code;
+    if ((code = ov_fopen(file.u8string().c_str(), &vf))) {
+        throw std::runtime_error(vorbis_error_message(code));
+    }
+    
+    std::vector<char> data;
+
+    vorbis_info* info = ov_info(&vf, -1);
+    uint channels = info->channels;
+    uint sampleRate = info->rate;
+
+    if (!headerOnly) {
+        const int bufferSize = 4096;
+        int section = 0;
+        char buffer[bufferSize];
+
+        bool eof = false;
+        while (!eof) {
+            long ret = ov_read(&vf, buffer, bufferSize, 0, 2, true, &section);
+            if (ret == 0) {
+                eof = true;
+            } else if (ret < 0) {
+                std::cerr << "ogg::load_pcm: " << vorbis_error_message(ret) << std::endl;
+            } else {
+                data.insert(data.end(), std::begin(buffer), std::end(buffer));
+            }
+        }
+    }
+    
+    ov_clear(&vf);
+    return new audio::PCM(data, channels, 16, sampleRate);
+}

src/coders/ogg.h

@@ -0,0 +1,14 @@
+#ifndef CODERS_OGG_H_
+#define CODERS_OGG_H_
+
+#include <filesystem>
+
+namespace audio {
+    struct PCM;
+}
+
+namespace ogg {
+    extern audio::PCM* load_pcm(const std::filesystem::path& file, bool headerOnly);
+}
+
+#endif // CODERS_OGG_H_