first decoding, temp

CMakeLists.txt

@@ -6,6 +6,7 @@ function(em_file name)
             ${CMAKE_SOURCE_DIR}/${name}.cpp
             -o ${CMAKE_BINARY_DIR}/${name}.js 
             -s WASM=0
+            -g4
             )
 endfunction(em_file)
 

index.html

@@ -21,14 +21,28 @@
             var src = new Uint8Array(buffer);
             var ptr = Module._malloc(buffer.byteLength);
             var arr = new Uint8Array(Module.HEAPU8.buffer, ptr, buffer.byteLength);
+            var ctx = new AudioContext();
+            var time = 0;
             arr.set(src, 0);
             
-            var stream = new Module.MadStream();
-            var frame = new Module.MadFrame();
+            var decoder = new Module.Decoder();
+            decoder.addFragment(ptr, buffer.byteLength);
             
-            stream.setBuffer(ptr, buffer.byteLength);
-            frame.decode(stream);
-            debugger;
+            while (decoder.hasMore()) {
+                var audio = decoder.decode(1);
+                if (audio === undefined) {
+                    if (decoder.hasMore() === false) {
+                        break;
+                    }
+                }
+                var source = ctx.createBufferSource();
+                source.buffer = audio;
+                source.connect(ctx.destination);
+                source.start(time);
+                time += audio.duration;
+            }
+            
+            decoder.delete();
         }
         reader.readAsArrayBuffer(file);
         

wrapper.cpp

@@ -1,4 +1,5 @@
 #include "wrapper.h"
+#include <string> 
 
 MadHeader * mad_header_create()
 {
@@ -16,13 +17,13 @@ MadFrame * mad_frame_create()
 
 emscripten::val MadFrame::getOverlap() const
 {
-    unsigned char* ptr = (unsigned char(*))overlap;
+    unsigned char* ptr = (unsigned char(*))*overlap;
     return emscripten::val(typed_memory_view(sizeof *overlap, ptr));
 }
 
 emscripten::val MadFrame::getSbsample() const
 {
-    unsigned char* ptr = (unsigned char(*))&sbsample;
+    unsigned char* ptr = (unsigned char(*))sbsample;
     return emscripten::val(typed_memory_view(sizeof sbsample, ptr));
 }
 
@@ -47,3 +48,150 @@ int MadFrame::decode(mad_stream* stream)
     return mad_frame_decode(this, stream);
 }
 
+emscripten::val MadPCM::samples() const
+{
+    mad_fixed_t* ptr = (mad_fixed_t(*))mad_pcm::samples;
+    return emscripten::val(typed_memory_view(sizeof mad_pcm::samples, ptr));
+}
+
+MadPCM* mad_pcm_create() {
+    MadPCM* pcm = new MadPCM();
+    return pcm;
+}
+
+MadSynth* mad_synth_create() {
+    MadSynth* synth = new MadSynth();
+    mad_synth_init(synth);
+    return synth;
+}
+
+void MadSynth::frame(const mad_frame* frame)
+{
+    mad_synth_frame(this, frame);
+}
+
+Decoder::Decoder():
+    sampleRate(0),
+    channels(0),
+    cachedLength(0),
+    currentBuffer(0),
+    currentBufferLength(0),
+    synth(),
+    stream(),
+    frame(),
+    context(0)
+{
+    mad_frame_init(&frame);
+    mad_stream_init(&stream);
+    mad_synth_init(&synth);
+    
+    emscripten::val AudioContext = emscripten::val::global("AudioContext");
+    if (!AudioContext.as<bool>()) {
+        printf("No global AudioContext, trying webkitAudioContext\n");
+        AudioContext = emscripten::val::global("webkitAudioContext");
+    }
+
+    printf("Got an AudioContext\n");
+    context = AudioContext.new_();
+}
+
+Decoder::~Decoder()
+{
+    context.call<void>("close");
+    
+    mad_synth_finish(&synth);
+    mad_stream_finish(&stream);
+    mad_frame_finish(&frame);
+    
+    if (currentBuffer != 0) {
+        free(currentBuffer);
+    }
+}
+
+void Decoder::addFragment(intptr_t bufferPtr, unsigned long length)
+{
+    if (currentBuffer != 0) {
+        printf("Adding more then 1 fragment is not supported yet");
+        throw 1;
+    }
+    currentBuffer = (unsigned char(*))bufferPtr;
+    currentBufferLength = length;
+    
+    mad_stream_buffer(&stream, currentBuffer, currentBufferLength);
+    framesLeft();
+}
+
+emscripten::val Decoder::decode(int count)
+{
+    emscripten::val ret = emscripten::val::undefined();
+    int result = -1;
+    
+    int available = framesLeft(count);
+    if (available > 0) {
+        ret = context.call<val>("createBuffer", channels, synth.pcm.length, sampleRate);
+    }
+    
+    if (result == 0) {
+        mad_synth_frame(&synth, &frame);
+        ret = context.call<val>("createBuffer", synth.pcm.channels, synth.pcm.length, synth.pcm.samplerate);
+        for (int i = 0; i < synth.pcm.channels; ++i) {
+            emscripten::val chan = ret.call<val>("getChannelData", i);
+            mad_fixed_t* sChan = synth.pcm.samples[i];
+            for (int j = 0; j < synth.pcm.length; ++j) {
+                float value = mad_f_todouble(sChan[j]);
+                chan.set(std::to_string(j), val(value));
+            }
+        }
+        
+        return ret;
+    }
+    
+    return ret;
+}
+
+bool Decoder::hasMore() const
+{
+    if (currentBuffer == 0) {
+        return false;
+    }
+    
+    return stream.error != MAD_ERROR_BUFLEN;
+}
+
+uint64_t Decoder::framesLeft(uint64_t max)
+{
+    if (currentBuffer == 0) {
+        return 0;
+    }
+    
+    if (!stream.sync) {
+        int result = mad_stream_sync(&stream);
+        if (result != 0) {
+            return 0;
+        }
+    }
+    
+    if (cachedLength == 0) {
+        mad_stream probe;
+        mad_header ph;
+        mad_stream_init(&probe);
+        mad_header_init(&ph);
+        mad_stream_skip(&probe, stream.skiplen);
+        while (probe.error != MAD_ERROR_BUFLEN || cachedLength < max) {
+            if (mad_header_decode(&ph, &probe) == 0) {
+                if (sampleRate == 0) {
+                    sampleRate = ph.samplerate;
+                    channels = MAD_NCHANNELS(&ph);
+                } else {
+                    if (sampleRate != ph.samplerate || channels != MAD_NCHANNELS(&ph)) {
+                        break;
+                    }
+                }
+                ++cachedLength;
+            }
+        }
+    } 
+    
+    return std::min(cachedLength, max);
+}
+

wrapper.h

@@ -47,9 +47,6 @@ MadHeader* mad_header_create();
 
 class MadFrame : public mad_frame {
 public:
-    const MadHeader& getHeader() const {return static_cast<const MadHeader&>(header);}
-    void setHeader(const MadHeader& head) {header = head;}
-    
     int getOptions() const {return options;}
     void setOptions(int lay) {options = lay;}
     
@@ -57,6 +54,7 @@ public:
     val getOverlap() const;
     
     int decode(mad_stream* stream);
+    const MadHeader* header() const {return static_cast<const MadHeader*>(&(mad_frame::header));}
 };
 MadFrame* mad_frame_create();
 
@@ -93,6 +91,56 @@ public:
 };
 MadStream* mad_stream_create();
 
+class MadPCM : public mad_pcm {
+public:
+    unsigned int getSamplerate() const {return samplerate;}
+    void setSamplerate(unsigned int value) {samplerate = value;}
+    
+    unsigned short getChannels() const {return channels;}
+    void setChannels(unsigned short value) {channels = value;}
+    
+    unsigned short getLength() const {return length;}
+    void setLength(unsigned short value) {length = value;}
+    
+    val samples() const;
+};
+
+MadPCM* mad_pcm_create();
+
+class MadSynth : public mad_synth {
+public:
+    unsigned int getPhase() const {return phase;}
+    void setPhase(unsigned int value) {phase = value;}
+    
+    const MadPCM* pcm() const {return static_cast<const MadPCM*>(&(mad_synth::pcm));}
+    void frame(mad_frame const * frame);
+};
+
+MadSynth* mad_synth_create();
+
+class Decoder {
+public:
+    Decoder();
+    ~Decoder();
+    
+    void addFragment(intptr_t bufferPtr, unsigned long length);
+    val decode(int count);
+    bool hasMore() const;
+    uint64_t framesLeft(uint64_t max = UINT64_MAX);
+    
+private:
+    uint32_t sampleRate;
+    uint8_t channels;
+    uint64_t cachedLength;
+    unsigned char* currentBuffer;
+    unsigned long currentBufferLength;
+    
+    mad_synth synth;
+    mad_stream stream;
+    mad_frame frame;
+    val context;
+};
+
 EMSCRIPTEN_BINDINGS(jsmad) {
     enum_<mad_layer>("mad_layer")
         .value("MAD_LAYER_I", MAD_LAYER_I)
@@ -159,8 +207,8 @@ EMSCRIPTEN_BINDINGS(jsmad) {
     class_<mad_frame>("mad_frame");
     class_<MadFrame, base<mad_frame>>("MadFrame")
         .constructor(&mad_frame_create, allow_raw_pointers())
-        .property("header", &MadFrame::getHeader, &MadFrame::setHeader)
         .property("options", &MadFrame::getOptions, &MadFrame::setOptions)
+        .function("header", &MadFrame::header, allow_raw_pointers())
         .function("sbsample", &MadFrame::getSbsample)
         .function("overlap", &MadFrame::getOverlap)
         .function("decode", &MadFrame::decode, allow_raw_pointers());
@@ -188,6 +236,30 @@ EMSCRIPTEN_BINDINGS(jsmad) {
     function("mad_stream_init", &mad_stream_init, allow_raw_pointers());
     function("mad_stream_finish", &mad_stream_finish, allow_raw_pointers());
     function("mad_stream_buffer", &mad_stream_buffer, allow_raw_pointers());
+    
+    class_<mad_pcm>("mad_pcm");
+    class_<MadPCM, base<mad_pcm>>("MadPCM")
+        .constructor(&mad_pcm_create, allow_raw_pointers())
+        .property("samplerate", &MadPCM::getSamplerate, &MadPCM::setSamplerate)
+        .property("channels", &MadPCM::getChannels, &MadPCM::setChannels)
+        .property("length", &MadPCM::getLength, &MadPCM::setLength)
+        .function("samples", &MadPCM::samples, allow_raw_pointers());
+        
+    function("mad_synth_init", &mad_synth_init, allow_raw_pointers());
+    function("mad_synth_frame", &mad_synth_frame, allow_raw_pointers());
+        
+    class_<mad_synth>("mad_synth");
+    class_<MadSynth, base<mad_synth>>("MadSynth")
+        .constructor(&mad_synth_create, allow_raw_pointers())
+        .property("phase", &MadSynth::getPhase, &MadSynth::setPhase)
+        .function("pcm", &MadSynth::pcm, allow_raw_pointers())
+        .function("frame", &MadSynth::frame, allow_raw_pointers());
+        
+    class_<Decoder>("Decoder")
+        .constructor<>()
+        .function("addFragment", &Decoder::addFragment)
+        .function("hasMore", &Decoder::hasMore)
+        .function("decode", &Decoder::decode);
 }
 
 #endif // WRAPPER_H