--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/frtest/decode-r.c	Wed Dec 14 23:11:20 2022 +0000
@@ -0,0 +1,75 @@
+/*
+ * gsmfr-decode-r is like gsmfr-decode, but writes the decoded PCM
+ * output in our "robe" format instead of WAV.
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <gsm.h>
+#include "../libgsmfrp/gsm_fr_preproc.h"
+#include "../libtest/binreader.h"
+#include "../libtest/robewrite.h"
+
+main(argc, argv)
+	char **argv;
+{
+	FILE *binf, *outf;
+	gsm dec_state;
+	struct gsmfr_preproc_state *pp_state;
+	uint8_t frame[BINFILE_MAX_FRAME];
+	int16_t pcm[160];
+	int rc, bfi, taf;
+
+	if (argc != 3) {
+		fprintf(stderr, "usage: %s input.gsm output.robe\n", argv[0]);
+		exit(1);
+	}
+	binf = fopen(argv[1], "r");
+	if (!binf) {
+		perror(argv[1]);
+		exit(1);
+	}
+	outf = fopen(argv[2], "w");
+	if (!outf) {
+		perror(argv[2]);
+		exit(1);
+	}
+	dec_state = gsm_create();
+	if (!dec_state) {
+		fprintf(stderr, "gsm_create() failed!\n");
+		exit(1);
+	}
+	pp_state = gsmfr_preproc_create();
+	if (!pp_state) {
+		fprintf(stderr, "gsmfr_preproc_create() failed!\n");
+		exit(1);
+	}
+	for (;;) {
+		rc = binfile_read_frame(binf, frame);
+		if (rc < 0) {
+			fprintf(stderr, "error: garbage in %s\n", argv[1]);
+			exit(1);
+		}
+		if (!rc)
+			break;
+		if (frame[0] == 0xBF) {
+			bfi = 1;
+			taf = frame[1] & 1;
+		} else if ((frame[0] & 0xF0) == 0xD0)
+			bfi = 0;
+		else {
+			fprintf(stderr, "error: %s is not in FR codec format\n",
+				argv[1]);
+			exit(1);
+		}
+		if (bfi)
+			gsmfr_preproc_bfi(pp_state, taf, frame);
+		else
+			gsmfr_preproc_good_frame(pp_state, frame);
+		gsm_decode(dec_state, frame, pcm);
+		write_pcm_to_robe(outf, pcm);
+	}
+	fclose(outf);
+	exit(0);
+}