1 files changed, 196 insertions, 0 deletions
diff --git a/modules/g722/g722.c b/modules/g722/g722.c
new file mode 100644
index 0000000..5e07e3a
--- /dev/null
+++ b/modules/g722/g722.c
@@ -0,0 +1,196 @@
+/**
+ * @file g722.c  G.722 audio codec
+ *
+ * Copyright (C) 2010 Creytiv.com
+ */
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <re.h>
+#include <baresip.h>
+#define SPANDSP_EXPOSE_INTERNAL_STRUCTURES 1
+#include <spandsp.h>
+
+
+#define DEBUG_MODULE "g722"
+#define DEBUG_LEVEL 5
+#include <re_dbg.h>
+
+
+/*
+  http://www.soft-switch.org/spandsp-modules.html
+ */
+
+/* From RFC 3551:
+
+ 4.5.2 G722
+
+   G722 is specified in ITU-T Recommendation G.722, "7 kHz audio-coding
+   within 64 kbit/s".  The G.722 encoder produces a stream of octets,
+   each of which SHALL be octet-aligned in an RTP packet.  The first bit
+   transmitted in the G.722 octet, which is the most significant bit of
+   the higher sub-band sample, SHALL correspond to the most significant
+   bit of the octet in the RTP packet.
+
+   Even though the actual sampling rate for G.722 audio is 16,000 Hz,
+   the RTP clock rate for the G722 payload format is 8,000 Hz because
+   that value was erroneously assigned in RFC 1890 and must remain
+   unchanged for backward compatibility.  The octet rate or sample-pair
+   rate is 8,000 Hz.
+ */
+
+enum {
+	G722_SAMPLE_RATE = 16000,
+	G722_BITRATE_48k = 48000,
+	G722_BITRATE_56k = 56000,
+	G722_BITRATE_64k = 64000
+};
+
+
+struct auenc_state {
+	g722_encode_state_t enc;
+};
+
+struct audec_state {
+	g722_decode_state_t dec;
+};
+
+
+static int encode_update(struct auenc_state **aesp,
+			 const struct aucodec *ac,
+			 struct auenc_param *prm, const char *fmtp)
+{
+	struct auenc_state *st;
+	int err = 0;
+	(void)prm;
+	(void)fmtp;
+
+	if (!aesp || !ac)
+		return EINVAL;
+
+	if (*aesp)
+		return 0;
+
+	st = mem_alloc(sizeof(*st), NULL);
+	if (!st)
+		return ENOMEM;
+
+	if (!g722_encode_init(&st->enc, G722_BITRATE_64k, 0)) {
+		DEBUG_WARNING("g722_encode_init failed\n");
+		err = EPROTO;
+		goto out;
+	}
+
+ out:
+	if (err)
+		mem_deref(st);
+	else
+		*aesp = st;
+
+	return err;
+}
+
+
+static int decode_update(struct audec_state **adsp,
+			 const struct aucodec *ac, const char *fmtp)
+{
+	struct audec_state *st;
+	int err = 0;
+	(void)fmtp;
+
+	if (!adsp || !ac)
+		return EINVAL;
+
+	if (*adsp)
+		return 0;
+
+	st = mem_alloc(sizeof(*st), NULL);
+	if (!st)
+		return ENOMEM;
+
+	if (!g722_decode_init(&st->dec, G722_BITRATE_64k, 0)) {
+		DEBUG_WARNING("g722_decode_init failed\n");
+		err = EPROTO;
+		goto out;
+	}
+
+ out:
+	if (err)
+		mem_deref(st);
+	else
+		*adsp = st;
+
+	return err;
+}
+
+
+static int encode(struct auenc_state *st, uint8_t *buf, size_t *len,
+		  const int16_t *sampv, size_t sampc)
+{
+	int n;
+
+	n = g722_encode(&st->enc, buf, sampv, (int)sampc);
+	if (n <= 0) {
+		DEBUG_WARNING("g722_encode: len=%d\n", n);
+		return EPROTO;
+	}
+	else if (n > (int)*len) {
+		DEBUG_WARNING("encode: wrote %d > %d buf\n", n, *len);
+		return EOVERFLOW;
+	}
+
+	*len = n;
+
+	return 0;
+}
+
+
+static int decode(struct audec_state *st, int16_t *sampv, size_t *sampc,
+		  const uint8_t *buf, size_t len)
+{
+	int n;
+
+	if (!st || !sampv || !buf)
+		return EINVAL;
+
+	n = g722_decode(&st->dec, sampv, buf, (int)len);
+	if (n < 0) {
+		DEBUG_WARNING("g722_decode: n=%d\n", n);
+		return EPROTO;
+	}
+
+	*sampc = n;
+
+	return 0;
+}
+
+
+static struct aucodec g722 = {
+	LE_INIT, "9", "G722", 8000, 1, NULL,
+	encode_update, encode,
+	decode_update, decode, NULL,
+	NULL, NULL
+};
+
+
+static int module_init(void)
+{
+	aucodec_register(&g722);
+	return 0;
+}
+
+
+static int module_close(void)
+{
+	aucodec_unregister(&g722);
+	return 0;
+}
+
+
+/** Module exports */
+EXPORT_SYM const struct mod_export DECL_EXPORTS(g722) = {
+	"g722",
+	"codec",
+	module_init,
+	module_close
+};