--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ae-dec-dhf/gen-test-frames.c	Tue May 14 08:13:01 2024 +0000
@@ -0,0 +1,59 @@
+/*
+ * This program generates some test EFR frames that are meant to be fed
+ * to the uplink input of the alien GSM network under study, seeking to
+ * test if the AMR-EFR hybrid decoder's handling of DHF matches our model.
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <gsm_efr.h>
+#include <tw_amr.h>
+
+static FILE *outf;
+
+static void
+emit_mr122_dhf()
+{
+	uint8_t frame[EFR_RTP_FRAME_LEN];
+
+	EFR_params2frame(amr_dhf_mr122, frame);
+	fwrite(frame, 1, EFR_RTP_FRAME_LEN, outf);
+}
+
+static void
+emit_mixed_dhf()
+{
+	int16_t params[EFR_NUM_PARAMS];
+	uint8_t frame[EFR_RTP_FRAME_LEN];
+
+	memcpy(params, amr_dhf_gsmefr, sizeof(int16_t) * 18);
+	memcpy(params + 18, amr_dhf_mr122 + 18, sizeof(int16_t) * 39);
+	EFR_params2frame(params, frame);
+	fwrite(frame, 1, EFR_RTP_FRAME_LEN, outf);
+}
+
+main(argc, argv)
+	char **argv;
+{
+	if (argc != 2) {
+		fprintf(stderr, "usage: %s gsmx-out-file\n", argv[0]);
+		exit(1);
+	}
+	outf = fopen(argv[1], "w");
+	if (!outf) {
+		perror(argv[1]);
+		exit(1);
+	}
+	emit_mr122_dhf();
+	emit_mr122_dhf();
+	emit_mixed_dhf();
+	fwrite(EFR_decoder_homing_frame, 1, EFR_RTP_FRAME_LEN, outf);
+	emit_mixed_dhf();
+	emit_mixed_dhf();
+	emit_mr122_dhf();
+	fclose(outf);
+	exit(0);
+}