Add automatic phase correction with cross-correlation detection and manual override

- Implement cross-correlation-based phase inversion detection
- Add --force-invert-phase flag for manual override and testing
- Add --no-phase-correction flag to disable automatic detection
- Update README with comprehensive documentation
- Improve phase detection sensitivity and add detailed logging
- Ensure consistent IR polarity for easier mixing of multiple IRs

main.go

@@ -83,6 +83,14 @@ func main() {
 				Name:  "plot-ir",
 				Usage: "Plot the generated regular IR waveform to ir_plot.png",
 			},
+			&cli.BoolFlag{
+				Name:  "no-phase-correction",
+				Usage: "Disable automatic phase correction (use if you know the phase is correct)",
+			},
+			&cli.BoolFlag{
+				Name:  "force-invert-phase",
+				Usage: "Force inversion of the recorded sweep (for testing/manual override)",
+			},
 		},
 		Action: func(c *cli.Context) error {
 			// Read sweep WAV file
@@ -118,8 +126,19 @@ func main() {
 				recordedFiltered = convolve.CascadeHighcut(recordedFiltered, recSampleRate, highcutHz, cutSlope)
 			}
 
+			// Force phase inversion if requested
+			if c.Bool("force-invert-phase") {
+				log.Printf("Forcing phase inversion of recorded sweep (manual override)")
+				recordedFiltered = convolve.InvertPhase(recordedFiltered)
+			}
+
 			log.Println("Performing deconvolution...")
-			ir := convolve.Deconvolve(sweepData.PCMData, recordedFiltered)
+			var ir []float64
+			if c.Bool("no-phase-correction") {
+				ir = convolve.Deconvolve(sweepData.PCMData, recordedFiltered)
+			} else {
+				ir = convolve.DeconvolveWithPhaseCorrection(sweepData.PCMData, recordedFiltered)
+			}
 			log.Printf("Deconvolution result: %d samples", len(ir))
 
 			log.Println("Trimming silence...")
@@ -204,7 +223,12 @@ func main() {
 			if c.Bool("mpt") {
 				log.Println("Generating minimum phase transform...")
 				// Use the original 96kHz IR for MPT generation
-				originalIR := convolve.Deconvolve(sweepData.PCMData, recordedData.PCMData)
+				var originalIR []float64
+				if c.Bool("no-phase-correction") {
+					originalIR = convolve.Deconvolve(sweepData.PCMData, recordedData.PCMData)
+				} else {
+					originalIR = convolve.DeconvolveWithPhaseCorrection(sweepData.PCMData, recordedData.PCMData)
+				}
 				originalIR = convolve.TrimSilence(originalIR, 1e-5)
 				mptIR := convolve.MinimumPhaseTransform(originalIR)
 				mptIR = convolve.Normalize(mptIR, c.Float64("normalize"))