lal_transferfunction: don't compute transfer functions until all input channels are nonzero.

gstlal-calibration/gst/lal/gstlal_transferfunction.c

@@ -122,6 +122,7 @@ enum property {
 	ARG_LOW_PASS,
 	ARG_TRANSFER_FUNCTIONS,
 	ARG_FIR_FILTERS,
+	ARG_INPUT_MAY_BE_ZERO,
 	ARG_FAKE
 };
 
@@ -423,6 +424,10 @@ static gboolean find_transfer_functions_ ## DTYPE(GSTLALTransferFunction *elemen
 	stride = element->fft_length - element->fft_overlap; \
 	num_tfs = element->channels - 1; \
 	DTYPE *real_fft = (DTYPE *) element->workspace.w ## S_OR_D ## pf.fft; \
+ \
+	/* Check a few inputs to see if we have valid data yet */ \
+	for(i = 0; i < 2 * element->channels; i++) \
+		success &= isnormal(src[i]) || (element->input_may_be_zero && src[i] == 0.0); \
  \
 	/* Determine how many fft's we will calculate from combined leftover and new input data */ \
 	num_ffts = minimum64((element->workspace.w ## S_OR_D ## pf.num_leftover + stride - 1) / stride, element->num_ffts - element->workspace.w ## S_OR_D ## pf.num_ffts_in_avg); \
@@ -1441,6 +1446,10 @@ static void set_property(GObject *object, enum property id, const GValue *value,
 		gstlal_doubles_from_g_value_array(g_value_get_boxed(value), element->fir_filters, &m);
 		break;
 
+	case ARG_INPUT_MAY_BE_ZERO:
+		element->input_may_be_zero = g_value_get_boolean(value);
+		break;
+
 	default:
 		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, id, pspec);
 		break;
@@ -1535,6 +1544,10 @@ static void get_property(GObject *object, enum property id, GValue *value, GPara
 		}
 		break;
 
+	case ARG_INPUT_MAY_BE_ZERO:
+		g_value_set_boolean(value, element->input_may_be_zero);
+		break;
+
 	default:
 		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, id, pspec);
 		break;
@@ -1752,6 +1765,15 @@ static void gstlal_transferfunction_class_init(GSTLALTransferFunctionClass *klas
 		),
 		G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | GST_PARAM_CONTROLLABLE
 	);
+	properties[ARG_INPUT_MAY_BE_ZERO] = g_param_spec_boolean(
+		"input-may-be-zero",
+		"Input may be zero",
+		"Set to True if transfer functions should be computed even if an input\n\t\t\t"
+		"channel contains zeros. Default is False, to prevent errors when an\n\t\t\t"
+		"input channel has no data yet at start of stream, etc.",
+		FALSE,
+		G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | G_PARAM_CONSTRUCT
+	);
 
 
 	g_object_class_install_property(
@@ -1824,6 +1846,11 @@ static void gstlal_transferfunction_class_init(GSTLALTransferFunctionClass *klas
 		ARG_FIR_FILTERS,
 		properties[ARG_FIR_FILTERS]
 	);
+	g_object_class_install_property(
+		gobject_class,
+		ARG_INPUT_MAY_BE_ZERO,
+		properties[ARG_INPUT_MAY_BE_ZERO]
+	);
 }
 
 

gstlal-calibration/gst/lal/gstlal_transferfunction.h

@@ -143,6 +143,7 @@ struct _GSTLALTransferFunction {
 	int low_pass;
 	complex double *transfer_functions;
 	double *fir_filters;
+	gboolean input_may_be_zero;
 };
 
 

gstlal-calibration/tests/lal_transferfunction_test.py

@@ -126,7 +126,8 @@ def lal_transferfunction_02(pipeline, name):
 	witness1 = calibration_parts.mkadder(pipeline, calibration_parts.list_srcs(pipeline, calibration_parts.highpass(pipeline, hoft, rate, fcut = 400), calibration_parts.lowpass(pipeline, noise, rate, fcut = 400)))
 	witness2 = calibration_parts.mkadder(pipeline, calibration_parts.list_srcs(pipeline, calibration_parts.lowpass(pipeline, hoft, rate, fcut = 600), calibration_parts.highpass(pipeline, noise, rate, fcut = 600)))
 
-	clean_data = calibration_parts.clean_data(pipeline, hoft, rate, calibration_parts.list_srcs(pipeline, witness1, witness2), rate, 4 * rate, 3 * rate + 1, 128, rate * test_duration, int(0.5 * rate), 5.0, filename = "highpass_lowpass_tfs.txt")
+	hoft = calibration_parts.highpass(pipeline, hoft, rate)
+	clean_data = calibration_parts.clean_data(pipeline, hoft, rate, calibration_parts.list_srcs(pipeline, witness1, witness2), rate, 4 * rate, 2 * rate, 128, rate * test_duration, int(0.5 * rate), 10.0, filename = "highpass_lowpass_tfs.txt")
 	pipeparts.mknxydumpsink(pipeline, clean_data, "%s_out.txt" % name)
 
 	return pipeline