Added chip channel allocation mode option

This option allows to select one of three different chip channel allocation modes.

README.md

@@ -170,6 +170,7 @@ To remove MIDI Sequencer, define `OPNMIDI_DISABLE_MIDI_SEQUENCER` macro and remo
  * Added an ability to set number of loops
  * Added an ability to disable/enable playing of selected MIDI channels
  * Fixed memory damages and crashes while playing XMI files
+ * Added the chip channels allocation mode option
 
 ## 1.5.0.1 2020-10-11
  * Fixed an incorrect timer processing when using a real-time interface

include/opnmidi.h

@@ -123,7 +123,26 @@ enum OPNMIDI_VolumeModels
     /*! Logarithmic volume scale, used in Apogee Sound System. */
     OPNMIDI_VolumeModel_APOGEE,
     /*! Aproximated and shorted volume map table. Similar to general, but has less granularity. */
-    OPNMIDI_VolumeModel_9X
+    OPNMIDI_VolumeModel_9X,
+    /*! Count of available volume model modes */
+    OPNMIDI_VolumeModel_Count
+};
+
+/*!
+ * \brief Algorithms of channel allocation for new notes
+ */
+enum OPNMIDI_ChannelAlloc
+{
+    /*! Automatical choise of the method according to the volume model and internal preferrences */
+    OPNMIDI_ChanAlloc_AUTO = -1,
+    /*! Take only channels that has expired sounding delay */
+    OPNMIDI_ChanAlloc_OffDelay,
+    /*! Take any first released channel with the same instrument */
+    OPNMIDI_ChanAlloc_SameInst,
+    /*! Take any first released channel */
+    OPNMIDI_ChanAlloc_AnyReleased,
+    /*! Count of available channel allocation modes */
+    OPNMIDI_ChanAlloc_Count
 };
 
 /**
@@ -477,6 +496,20 @@ extern OPNMIDI_DECLSPEC void opn2_setVolumeRangeModel(struct OPN2_MIDIPlayer *de
  */
 extern OPNMIDI_DECLSPEC int opn2_getVolumeRangeModel(struct OPN2_MIDIPlayer *device);
 
+/**
+ * @brief Set the channel allocation mode
+ * @param device Instance of the library
+ * @param chanalloc Channel allocation mode (#ADLMIDI_ChannelAlloc)
+ */
+extern OPNMIDI_DECLSPEC void opn2_setChannelAllocMode(struct OPN2_MIDIPlayer *device, int chanalloc);
+
+/**
+ * @brief Get the current channel allocation mode
+ * @param device Instance of the library
+ * @return Channel allocation mode (#ADLMIDI_ChannelAlloc)
+ */
+extern OPNMIDI_DECLSPEC int opn2_getChannelAllocMode(struct OPN2_MIDIPlayer *device);
+
 /**
  * @brief Load WOPN bank file from File System
  *

src/opnmidi.cpp

@@ -459,7 +459,7 @@ OPNMIDI_EXPORT void opn2_setLogarithmicVolumes(struct OPN2_MIDIPlayer *device, i
     }
 }
 
-OPNMIDI_EXPORT void opn2_setVolumeRangeModel(OPN2_MIDIPlayer *device, int volumeModel)
+OPNMIDI_EXPORT void opn2_setVolumeRangeModel(struct OPN2_MIDIPlayer *device, int volumeModel)
 {
     if(!device)
         return;
@@ -476,6 +476,27 @@ OPNMIDI_EXPORT void opn2_setVolumeRangeModel(OPN2_MIDIPlayer *device, int volume
     }
 }
 
+OPNMIDI_EXPORT void opn2_setChannelAllocMode(struct OPN2_MIDIPlayer *device, int chanalloc)
+{
+    if(!device)
+        return;
+    MidiPlayer *play = GET_MIDI_PLAYER(device);
+    assert(play);
+    Synth &synth = *play->m_synth;
+    if(chanalloc < -1 || chanalloc >= OPNMIDI_ChanAlloc_Count)
+        chanalloc = OPNMIDI_ChanAlloc_AUTO;
+    synth.m_channelAlloc = static_cast<OPNMIDI_ChannelAlloc>(chanalloc);
+}
+
+OPNMIDI_EXPORT int opn2_getChannelAllocMode(struct OPN2_MIDIPlayer *device)
+{
+    if(!device)
+        return -1;
+    MidiPlayer *play = GET_MIDI_PLAYER(device);
+    assert(play);
+    return static_cast<int>(play->m_synth->m_channelAlloc);
+}
+
 OPNMIDI_EXPORT int opn2_getVolumeRangeModel(struct OPN2_MIDIPlayer *device)
 {
     if(!device)

src/opnmidi_midiplay.cpp

@@ -1274,14 +1274,39 @@ int64_t OPNMIDIplay::calculateChipChannelGoodness(size_t c, const MIDIchannel::N
     const OpnChannel &chan = m_chipChannels[c];
     int64_t koff_ms = chan.koff_time_until_neglible_us / 1000;
     int64_t s = -koff_ms;
+    OPNMIDI_ChannelAlloc allocType = synth.m_channelAlloc;
+
+    if(allocType == OPNMIDI_ChanAlloc_AUTO)
+    {
+        if(synth.m_musicMode == Synth::MODE_CMF)
+            allocType = OPNMIDI_ChanAlloc_SameInst;
+        else
+            allocType = OPNMIDI_ChanAlloc_OffDelay;
+    }
 
     // Rate channel with a releasing note
     if(s < 0 && chan.users.empty())
     {
+        bool isSame = (chan.recent_ins == ins);
         s -= 40000;
+
         // If it's same instrument, better chance to get it when no free channels
-        if(chan.recent_ins == ins)
-            s = (synth.m_musicMode == Synth::MODE_CMF) ? 0 : -koff_ms;
+        switch(allocType)
+        {
+        case OPNMIDI_ChanAlloc_SameInst:
+            if(isSame)
+                s = 0; // Re-use releasing channel with the same instrument
+            break;
+        case OPNMIDI_ChanAlloc_AnyReleased:
+            s = 0; // Re-use any releasing channel
+            break;
+        default:
+        case OPNMIDI_ChanAlloc_OffDelay:
+            if(isSame)
+                s =  -koff_ms; // Wait until releasing sound will complete
+            break;
+        }
+
         return s;
     }
 

src/opnmidi_opn2.cpp

@@ -218,6 +218,7 @@ OPN2::OPN2() :
     m_masterVolume(MasterVolumeDefault),
     m_musicMode(MODE_MIDI),
     m_volumeScale(VOLUME_Generic),
+    m_channelAlloc(OPNMIDI_ChanAlloc_AUTO),
     m_lfoEnable(false),
     m_lfoFrequency(0),
     m_chipFamily(OPNChip_OPN2)
@@ -541,6 +542,7 @@ void OPN2::setVolumeScaleModel(OPNMIDI_VolumeModels volumeModel)
 {
     switch(volumeModel)
     {
+    default:
     case OPNMIDI_VolumeModel_AUTO://Do nothing until restart playing
         break;
 

src/opnmidi_opn2.hpp

@@ -130,6 +130,9 @@ class OPN2
         VOLUME_9X
     } m_volumeScale;
 
+    //! Channel allocation algorithm
+    OPNMIDI_ChannelAlloc m_channelAlloc;
+
     //! Reserved
     bool m_lfoEnable;
     uint8_t m_lfoFrequency;

utils/midi2vgm/midi2vgm.cpp

@@ -68,6 +68,40 @@ extern "C"
     extern OPNMIDI_DECLSPEC void opn2_set_vgm_out_path(const char *path);
 }
 
+const char* volume_model_to_str(int vm)
+{
+    switch(vm)
+    {
+    default:
+    case OPNMIDI_VolumeModel_Generic:
+        return "Generic";
+    case OPNMIDI_VolumeModel_NativeOPN2:
+        return "Native OPN2";
+    case OPNMIDI_VolumeModel_DMX:
+        return "DMX";
+    case OPNMIDI_VolumeModel_APOGEE:
+        return "Apogee Sound System";
+    case OPNMIDI_VolumeModel_9X:
+        return "9X";
+    }
+}
+
+const char* chanalloc_to_str(int vm)
+{
+    switch(vm)
+    {
+    default:
+    case OPNMIDI_ChanAlloc_AUTO:
+        return "<auto>";
+    case OPNMIDI_ChanAlloc_OffDelay:
+        return "Off Delay";
+    case OPNMIDI_ChanAlloc_SameInst:
+        return "Same instrument";
+    case OPNMIDI_ChanAlloc_AnyReleased:
+        return "Any released";
+    }
+}
+
 static void printError(const char *err)
 {
     std::fprintf(stderr, "\nERROR: %s\n\n", err);
@@ -199,6 +233,10 @@ int main(int argc, char **argv)
             "    3 DMX\n"
             "    4 Apogee Sound System\n"
             "    5 9x\n"
+            " -ca <num> Chooses one of chip channel allocation modes: \n"
+            "    0 Sounding delay"
+            "    1 Released channel with the same instrument"
+            "    2 Any released channel"
             " -na               Disables the automatical arpeggio\n"
             " -z                Make a compressed VGZ file\n"
             " -frb              Enables full-ranged CC74 XG Brightness controller\n"
@@ -236,6 +274,7 @@ int main(int argc, char **argv)
     int loopEnabled = 0;
     int volumeModel = OPNMIDI_VolumeModel_AUTO;
     int autoArpeggioEnabled = 0;
+    int chanAlloc = OPNMIDI_ChanAlloc_AUTO;
     size_t soloTrack = ~static_cast<size_t>(0);
     int chipsCount = 1;// Single-chip by default
     std::vector<int> muteChannels;
@@ -267,6 +306,15 @@ int main(int argc, char **argv)
             }
             volumeModel = static_cast<int>(std::strtol(argv[++arg], NULL, 10));
         }
+        else if(!std::strcmp("-ca", argv[arg]))
+        {
+            if(arg + 1 >= argc)
+            {
+                printError("The option -carequires an argument!\n");
+                return 1;
+            }
+            chanAlloc = static_cast<int>(std::strtol(argv[++arg], NULL, 10));
+        }
         else if(!std::strcmp("--chips", argv[arg]))
         {
             if(arg + 1 >= argc)
@@ -350,6 +398,7 @@ int main(int argc, char **argv)
     opn2_setSoftPanEnabled(myDevice, 0);
     opn2_setLoopEnabled(myDevice, loopEnabled);
     opn2_setAutoArpeggio(myDevice, autoArpeggioEnabled);
+    opn2_setChannelAllocMode(myDevice, chanAlloc);
 
 #ifdef DEBUG_TRACE_ALL_EVENTS
     //Hook all MIDI events are ticking while generating an output buffer
@@ -397,6 +446,8 @@ int main(int argc, char **argv)
 
     std::fprintf(stdout, " - Number of chips %d\n", opn2_getNumChipsObtained(myDevice));
     std::fprintf(stdout, " - Track count: %lu\n", (unsigned long)opn2_trackCount(myDevice));
+    std::fprintf(stdout, " - Volume model: %s\n", volume_model_to_str(opn2_getVolumeRangeModel(myDevice)));
+    std::fprintf(stdout, " - Channel allocation mode: %s\n", chanalloc_to_str(opn2_getChannelAllocMode(myDevice)));
 
     if(soloTrack != ~(size_t)0)
     {

utils/midiplay/opnplay.cpp

@@ -122,6 +122,22 @@ const char* volume_model_to_str(int vm)
     }
 }
 
+const char* chanalloc_to_str(int vm)
+{
+    switch(vm)
+    {
+    default:
+    case OPNMIDI_ChanAlloc_AUTO:
+        return "<auto>";
+    case OPNMIDI_ChanAlloc_OffDelay:
+        return "Off Delay";
+    case OPNMIDI_ChanAlloc_SameInst:
+        return "Same instrument";
+    case OPNMIDI_ChanAlloc_AnyReleased:
+        return "Any released";
+    }
+}
+
 static void printError(const char *err)
 {
     std::fprintf(stderr, "\nERROR: %s\n\n", err);
@@ -254,6 +270,10 @@ int main(int argc, char **argv)
             "    3 DMX\n"
             "    4 Apogee Sound System\n"
             "    5 9x\n"
+            " -ca <num> Chooses one of chip channel allocation modes: \n"
+            "    0 Sounding delay"
+            "    1 Released channel with the same instrument"
+            "    2 Any released channel"
             " -frb              Enables full-ranged CC74 XG Brightness controller\n"
             " -mc <nums>        Mute selected MIDI channels"
             "                     where <num> - space separated numbers list (0-based!):"
@@ -307,6 +327,7 @@ int main(int argc, char **argv)
     bool fullRangedBrightness = false;
     int loopEnabled = 1;
     int autoArpeggioEnabled = 0;
+    int chanAlloc = OPNMIDI_ChanAlloc_AUTO;
     bool fullPanEnabled = false;
     int emulator = OPNMIDI_EMU_MAME;
     int volumeModel = OPNMIDI_VolumeModel_AUTO;
@@ -357,6 +378,15 @@ int main(int argc, char **argv)
             }
             volumeModel = static_cast<int>(std::strtol(argv[++arg], NULL, 10));
         }
+        else if(!std::strcmp("-ca", argv[arg]))
+        {
+            if(arg + 1 >= argc)
+            {
+                printError("The option -carequires an argument!\n");
+                return 1;
+            }
+            chanAlloc = static_cast<int>(std::strtol(argv[++arg], NULL, 10));
+        }
         else if(!std::strcmp("--chips", argv[arg]))
         {
             if(arg + 1 >= argc)
@@ -457,6 +487,7 @@ int main(int argc, char **argv)
     opn2_setLoopEnabled(myDevice, recordWave ? 0 : loopEnabled);
     opn2_setVolumeRangeModel(myDevice, OPNMIDI_VolumeModel_Generic);
     opn2_setAutoArpeggio(myDevice, autoArpeggioEnabled);
+    opn2_setChannelAllocMode(myDevice, chanAlloc);
 #ifdef DEBUG_TRACE_ALL_EVENTS
     //Hook all MIDI events are ticking while generating an output buffer
     if(!recordWave)
@@ -503,6 +534,7 @@ int main(int argc, char **argv)
     std::fprintf(stdout, " - Number of chips %d\n", opn2_getNumChipsObtained(myDevice));
     std::fprintf(stdout, " - Track count: %lu\n", static_cast<unsigned long>(opn2_trackCount(myDevice)));
     std::fprintf(stdout, " - Volume model: %s\n", volume_model_to_str(opn2_getVolumeRangeModel(myDevice)));
+    std::fprintf(stdout, " - Channel allocation mode: %s\n", chanalloc_to_str(opn2_getChannelAllocMode(myDevice)));
 
     if(soloTrack != ~static_cast<size_t>(0u))
     {

utils/vlc_codec/libopnmidi.c

@@ -78,6 +78,10 @@
 #define VOLUME_MODEL_LONGTEXT N_( \
     "Declares volume scaling model which will affect volume levels.")
 
+#define CHANNEL_ALLOCATION_TEXT N_("Channel allocation mode")
+#define CHANNEL_ALLOCATION_LONGTEXT N_( \
+    "Declares the method of chip channel allocation for new notes.")
+
 #define FULL_RANGE_CC74_TEXT N_("Full-range of brightness")
 #define FULL_RANGE_CC74_LONGTEXT N_( \
     "Scale range of CC-74 \"Brightness\" with full 0~127 range. By default is only 0~64 affects the sounding.")
@@ -98,6 +102,16 @@ static const char * const volume_models_descriptions[] =
     NULL
 };
 
+static const int channel_alloc_values[] = { -1, 0, 1, 2 };
+static const char * const channel_alloc_descriptions[] =
+{
+    N_("Auto (defined by bank)"),
+    N_("By sounding delays"),
+    N_("Released channel of same instrument"),
+    N_("Any released channel"),
+    NULL
+};
+
 #define EMULATOR_TYPE_TEXT N_("OPN2 Emulation core")
 #define EMULATOR_TYPE_LINGTEXT N_( \
     "OPN2 Emulator that will be used to generate final sound.")
@@ -150,6 +164,9 @@ vlc_module_begin ()
     add_integer (CONFIG_PREFIX "volume-model", 0, VOLUME_MODEL_TEXT, VOLUME_MODEL_LONGTEXT, false )
         change_integer_list( volume_models_values, volume_models_descriptions )
 
+    add_integer (CONFIG_PREFIX "channel-allocation", -1, CHANNEL_ALLOCATION_TEXT, CHANNEL_ALLOCATION_LONGTEXT, false )
+        change_integer_list( channel_alloc_values, channel_alloc_descriptions )
+
     add_integer (CONFIG_PREFIX "emulator-type", 0, EMULATOR_TYPE_TEXT, EMULATOR_TYPE_LINGTEXT, false)
         change_integer_list( emulator_type_values, emulator_type_descriptions )
 
@@ -216,6 +233,8 @@ static int Open (vlc_object_t *p_this)
 
     opn2_setVolumeRangeModel(p_sys->synth, var_InheritInteger(p_this, CONFIG_PREFIX "volume-model"));
 
+    opn2_setChannelAllocMode(p_sys->synth, var_InheritInteger(p_this, CONFIG_PREFIX "channel-allocation"));
+
     opn2_setSoftPanEnabled(p_sys->synth, var_InheritBool(p_this, CONFIG_PREFIX "full-panning"));
 
     opn2_setFullRangeBrightness(p_sys->synth, var_InheritBool(p_this, CONFIG_PREFIX "full-range-brightness"));