microphone recording working with FMOD!!!

2026-01-14 18:02:41 +02:00
parent 96839e0e82
commit cb4d4036e7
12 changed files with 410 additions and 140 deletions
--- a/Assets/_PROJECT/Scripts/ModeGeneration/FMODMicLoopback.cs
+++ b/Assets/_PROJECT/Scripts/ModeGeneration/FMODMicLoopback.cs
@@ -0,0 +1,122 @@
+
+using FMOD;
+using FMODUnity;
+using System.Runtime.InteropServices;
+using UnityEngine;
+
+public class FMODMicLoopback : MonoBehaviour
+{
+    private uint LATENCY_MS = 50;
+    private uint DRIFT_MS = 1;
+
+    private uint samplesRecorded, samplesPlayed = 0;
+    private int nativeRate, nativeChannels = 0;
+    private uint recSoundLength = 0;
+    uint lastPlayPos = 0;
+    uint lastRecordPos = 0;
+    private uint driftThreshold = 0;
+    private uint desiredLatency = 0;
+    private uint adjustLatency = 0;
+    private int actualLatency = 0;
+    uint minRecordDelta = 0xFFFFFFFF;
+
+    private FMOD.CREATESOUNDEXINFO exInfo = new FMOD.CREATESOUNDEXINFO();
+
+    private FMOD.Sound recSound;
+    private FMOD.Channel channel;
+
+    // Start is called before the first frame update
+    void Start()
+    {
+        /*
+            Determine latency in samples.
+        */
+        FMODUnity.RuntimeManager.CoreSystem.getRecordDriverInfo(0, out _, 0, out _, out nativeRate, out _, out nativeChannels, out _);
+
+        driftThreshold = (uint)(nativeRate * DRIFT_MS) / 1000;
+        desiredLatency = (uint)(nativeRate * LATENCY_MS) / 1000;
+        adjustLatency = desiredLatency;
+        actualLatency = (int)desiredLatency;
+
+        /*
+            Create user sound to record into, then start recording.
+        */
+        exInfo.cbsize = Marshal.SizeOf(typeof(FMOD.CREATESOUNDEXINFO));
+        exInfo.numchannels = nativeChannels;
+        exInfo.format = FMOD.SOUND_FORMAT.PCM16;
+        exInfo.defaultfrequency = nativeRate;
+        exInfo.length = (uint)(nativeRate * sizeof(short) * nativeChannels);
+
+        FMODUnity.RuntimeManager.CoreSystem.createSound("", FMOD.MODE.LOOP_NORMAL | FMOD.MODE.OPENUSER, ref exInfo, out recSound);
+
+        FMODUnity.RuntimeManager.CoreSystem.recordStart(0, recSound, true);
+
+        recSound.getLength(out recSoundLength, FMOD.TIMEUNIT.PCM);
+    }
+
+    // Update is called once per frame
+    void Update()
+    {
+        /*
+            Determine how much has been recorded since we last checked
+        */
+        uint recordPos = 0;
+        FMODUnity.RuntimeManager.CoreSystem.getRecordPosition(0, out recordPos);
+
+        uint recordDelta = (recordPos >= lastRecordPos) ? (recordPos - lastRecordPos) : (recordPos + recSoundLength - lastRecordPos);
+        lastRecordPos = recordPos;
+        samplesRecorded += recordDelta;
+
+        if (recordDelta != 0 && (recordDelta < minRecordDelta))
+        {
+            minRecordDelta = recordDelta; // Smallest driver granularity seen so far
+            adjustLatency = (recordDelta <= desiredLatency) ? desiredLatency : recordDelta; // Adjust our latency if driver granularity is high
+        }
+
+        /*
+            Delay playback until our desired latency is reached.
+        */
+        if (!channel.hasHandle() && samplesRecorded >= adjustLatency)
+        {
+            FMODUnity.RuntimeManager.CoreSystem.getMasterChannelGroup(out FMOD.ChannelGroup mCG);
+            FMODUnity.RuntimeManager.CoreSystem.playSound(recSound, mCG, false, out channel);
+        }
+
+        /*
+            Determine how much has been played since we last checked.
+        */
+        if (channel.hasHandle())
+        {
+            uint playPos = 0;
+            channel.getPosition(out playPos, FMOD.TIMEUNIT.PCM);
+
+            uint playDelta = (playPos >= lastPlayPos) ? (playPos - lastPlayPos) : (playPos + recSoundLength - lastPlayPos);
+            lastPlayPos = playPos;
+            samplesPlayed += playDelta;
+
+            // Compensate for any drift.
+            int latency = (int)(samplesRecorded - samplesPlayed);
+            actualLatency = (int)((0.97f * actualLatency) + (0.03f * latency));
+
+            int playbackRate = nativeRate;
+            if (actualLatency < (int)(adjustLatency - driftThreshold))
+            {
+                // Playback position is catching up to the record position, slow playback down by 2%
+                playbackRate = nativeRate - (nativeRate / 50);
+            }
+
+            else if (actualLatency > (int)(adjustLatency + driftThreshold))
+            {
+                // Playback is falling behind the record position, speed playback up by 2%
+                playbackRate = nativeRate + (nativeRate / 50);
+            }
+
+            channel.setFrequency((float)playbackRate);
+        }
+    }
+
+    private void OnDestroy()
+    {
+        recSound.release();
+    }
+}