--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/efrtest/decode.c	Sat Nov 26 22:07:55 2022 +0000
@@ -0,0 +1,69 @@
+/*
+ * This file is the main module for gsmefr-decode utility.
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include "../libgsmefr/gsm_efr.h"
+#include "../libtest/binreader.h"
+#include "../libtest/wavwriter.h"
+#include "../libtest/pcmwrite.h"
+
+main(argc, argv)
+	char **argv;
+{
+	FILE *binf;
+	void *wav;
+	struct EFR_decoder_state *state;
+	uint8_t frame[BINFILE_MAX_FRAME];
+	int16_t pcm[160];
+	int rc, bfi, taf;
+
+	if (argc != 3) {
+		fprintf(stderr, "usage: %s input.gsmx output.wav\n", argv[0]);
+		exit(1);
+	}
+	binf = fopen(argv[1], "r");
+	if (!binf) {
+		perror(argv[1]);
+		exit(1);
+	}
+	wav = wav_write_open(argv[2], 8000, 16, 1);
+	if (!wav) {
+		perror(argv[2]);
+		exit(1);
+	}
+	state = EFR_decoder_create();
+	if (!state) {
+		perror("EFR_decoder_create()");
+		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) == 0xC0)
+			bfi = 0;
+		else {
+			fprintf(stderr,
+				"error: %s is not in EFR codec format\n",
+				argv[1]);
+			exit(1);
+		}
+		if (bfi)
+			EFR_decode_bfi_nodata(state, taf, pcm);
+		else
+			EFR_decode_frame(state, frame, 0, 0, pcm);
+		write_pcm_to_wav(wav, pcm);
+	}
+	wav_write_close(wav);
+	exit(0);
+}