From b47b6d7e3ec216c8915e9452505d5566111ce966 Mon Sep 17 00:00:00 2001
From: Jan Svabenik <jan@svabi.ch>
Date: Thu, 19 Mar 2026 12:25:09 +0100
Subject: [PATCH] Add batch extraction API to gpudemod

---
 cmd/sdrd/helpers.go              | 19 +++++++++++++------
 internal/demod/gpudemod/batch.go | 21 +++++++++++++++++++++
 2 files changed, 34 insertions(+), 6 deletions(-)
 create mode 100644 internal/demod/gpudemod/batch.go

diff --git a/cmd/sdrd/helpers.go b/cmd/sdrd/helpers.go
index 8f9fdcc..54926a4 100644
--- a/cmd/sdrd/helpers.go
+++ b/cmd/sdrd/helpers.go
@@ -83,14 +83,21 @@ func extractSignalIQBatch(iq []complex64, sampleRate int, centerHz float64, sign
 		}
 	}
 
-	for i, sig := range signals {
-		offset := sig.CenterHz - centerHz
-		if eng != nil {
-			if gpuOut, _, err := eng.ShiftFilterDecimate(iq, offset, sig.BWHz, decimTarget); err == nil && len(gpuOut) > 0 {
-				out[i] = gpuOut
-				continue
+	if eng != nil {
+		jobs := make([]gpudemod.ExtractJob, len(signals))
+		for i, sig := range signals {
+			jobs[i] = gpudemod.ExtractJob{OffsetHz: sig.CenterHz - centerHz, BW: sig.BWHz, OutRate: decimTarget}
+		}
+		if gpuOuts, _, err := eng.ShiftFilterDecimateBatch(iq, jobs); err == nil && len(gpuOuts) == len(signals) {
+			for i := range gpuOuts {
+				out[i] = gpuOuts[i]
 			}
+			return out
 		}
+	}
+
+	for i, sig := range signals {
+		offset := sig.CenterHz - centerHz
 		shifted := dsp.FreqShift(iq, sampleRate, offset)
 		cutoff := sig.BWHz / 2
 		if cutoff < 200 {
diff --git a/internal/demod/gpudemod/batch.go b/internal/demod/gpudemod/batch.go
new file mode 100644
index 0000000..1630fb3
--- /dev/null
+++ b/internal/demod/gpudemod/batch.go
@@ -0,0 +1,21 @@
+package gpudemod
+
+type ExtractJob struct {
+	OffsetHz float64
+	BW       float64
+	OutRate  int
+}
+
+func (e *Engine) ShiftFilterDecimateBatch(iq []complex64, jobs []ExtractJob) ([][]complex64, []int, error) {
+	outs := make([][]complex64, len(jobs))
+	rates := make([]int, len(jobs))
+	for i, job := range jobs {
+		out, rate, err := e.ShiftFilterDecimate(iq, job.OffsetHz, job.BW, job.OutRate)
+		if err != nil {
+			return nil, nil, err
+		}
+		outs[i] = out
+		rates[i] = rate
+	}
+	return outs, rates, nil
+}