--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/miscutil/amrts-pcm8-compact.c	Mon May 13 21:06:58 2024 +0000
@@ -0,0 +1,55 @@
+/*
+ * The set of AMR test sequences shipped by 3GPP as TS 26.074 includes
+ * not only linear PCM (13-bit left-justified) and AMR-encoded files,
+ * but also 8-bit PCM sequences in both A-law and mu-law.  However,
+ * those PCM8 sequences are shipped in a stupid and inconvenient format:
+ * each 8-bit PCM sample is expanded to a 16-bit word, written in LE
+ * byte order.  This utility converts a PCM8 test sequence file
+ * from this weird format into sane PCM8 format with one byte per sample.
+ * For this conversion, it does not matter whether the PCM8 test sequence
+ * in question is A-law or mu-law.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+main(argc, argv)
+	char **argv;
+{
+	FILE *inf, *outf;
+	int cdat, cpad;
+
+	if (argc != 3) {
+		fprintf(stderr, "usage: %s in-file out-file\n", argv[0]);
+		exit(1);
+	}
+	inf = fopen(argv[1], "r");
+	if (!inf) {
+		perror(argv[1]);
+		exit(1);
+	}
+	outf = fopen(argv[2], "w");
+	if (!outf) {
+		perror(argv[2]);
+		exit(1);
+	}
+	for (;;) {
+		cdat = getc(inf);
+		if (cdat < 0)
+			break;
+		cpad = getc(inf);
+		if (cpad < 0) {
+			fprintf(stderr, "error: %s has odd length\n", argv[1]);
+			exit(1);
+		}
+		if (cpad != 0) {
+			fprintf(stderr,
+				"error: presumed padding byte in %s is not 0\n",
+				argv[1]);
+			exit(1);
+		}
+		putc(cdat, outf);
+	}
+	fclose(outf);
+	exit(0);
+}