Improve odometry with rotation estimation, daemon stability, and RTSP fixes

- Add rotation estimation via log-polar phase correlation (EstimateRotation,
  rotateGray) — de-rotate before translation to avoid aliasing
- Track cumulative field rotation in Tracker, reject low-confidence frames
- Extract RTSP grabber into internal/rtspgrab module
- Daemon: pause odometry during slew (motion blur), auto-resume after settle
  delay, add /pause and /resume HTTP endpoints, switch shooting mode before
  opening camera, use ReqOpenCamera with rtsp_encode_type=1
- WebSocket heartbeat (ping/pong every 10s) to prevent idle disconnects
- FFmpeg low-latency flags (-fflags nobuffer, -probesize, -analyzeduration)
- Add SendRaw API for custom payloads, increase daemon HTTP timeout to 60s

💘 Generated with Crush

Assisted-by: Crush:/models/Qwen3.6-27B-uncensored-heretic-v2-Native-MTP-Preserved-Q4_K_M.gguf

dwarfctl/internal/odometry/odometry.go

@@ -19,20 +19,19 @@ import (
 	"os"
 )
 
-// Result holds the rotation estimated between two frames.
+// Result holds the motion estimated between two frames.
 type Result struct {
-	// PanPx / TiltPx are the image-plane shift (in resized pixels) of the scene
-	// from frame 1 to frame 2. Positive PanPx = scene moved right; positive
-	// TiltPx = scene moved down. To point back at the original target, slew the
-	// motors in the opposite direction.
+	// PanPx / TiltPx are the image-plane translation (in resized pixels).
 	PanPx  float64
 	TiltPx float64
 	// PanDeg / TiltDeg convert the pixel shift to degrees using the supplied FoV.
 	PanDeg  float64
 	TiltDeg float64
-	// Confidence in [0,1]: the normalized phase-correlation peak height. Higher
-	// is better; below ~0.05 the frames are likely too flat or the motion too
-	// large to be trusted.
+	// RotDeg is the estimated field rotation (degrees). Positive = scene rotated
+	// counter-clockwise. Dominant when the telescope points near zenith on an
+	// alt-az mount (azimuth rotation → field rotation, not translation).
+	RotDeg float64
+	// Confidence in [0,1].
 	Confidence float64
 	// Size is the FFT grid dimension actually used.
 	Size int
@@ -78,13 +77,31 @@ func Estimate(img1, img2 image.Image, fovXDeg, fovYDeg float64, size int) (Resul
 	g1 := toGrayDownscaled(img1, size, size)
 	g2 := toGrayDownscaled(img2, size, size)
 
-	dx, dy, conf := phaseCorrelation(g1, g2, size, size)
+	// Pass 1: estimate rotation (log-polar phase correlation).
+	rotDeg, confRot := EstimateRotation(g1, g2, size, size)
+
+	// Pass 2: de-rotate g2, then estimate translation on de-rotated images.
+	// This removes the rotation-induced aliasing that corrupts translation.
+	var dx, dy, confTrans float64
+	if absf(rotDeg) > 0.3 {
+		g2Derot := rotateGray(g2, size, rotDeg)
+		dx, dy, confTrans = phaseCorrelation(g1, g2Derot, size, size)
+	} else {
+		dx, dy, confTrans = phaseCorrelation(g1, g2, size, size)
+	}
+
+	// Use the higher-confidence metric as the overall confidence.
+	conf := confTrans
+	if confRot > conf {
+		conf = confRot
+	}
 
 	r := Result{
 		PanPx:      dx,
 		TiltPx:     dy,
 		PanDeg:     dx * fovXDeg / float64(size),
 		TiltDeg:    dy * fovYDeg / float64(size),
+		RotDeg:     rotDeg,
 		Confidence: conf,
 		Size:       size,
 	}