gstreamer/gst/rtp/gstrtpg726depay.c
2012-11-04 00:07:18 +00:00

384 lines
12 KiB
C

/* GStreamer
* Copyright (C) 1999 Erik Walthinsen <omega@cse.ogi.edu>
* Copyright (C) 2005 Edgard Lima <edgard.lima@indt.org.br>
* Copyright (C) 2005 Zeeshan Ali <zeenix@gmail.com>
* Copyright (C) 2008 Axis Communications <dev-gstreamer@axis.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <gst/rtp/gstrtpbuffer.h>
#include "gstrtpg726depay.h"
GST_DEBUG_CATEGORY_STATIC (rtpg726depay_debug);
#define GST_CAT_DEFAULT (rtpg726depay_debug)
#define DEFAULT_BIT_RATE 32000
#define SAMPLE_RATE 8000
#define LAYOUT_G726 "g726"
/* RtpG726Depay signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
#define DEFAULT_FORCE_AAL2 TRUE
enum
{
PROP_0,
PROP_FORCE_AAL2,
PROP_LAST
};
static GstStaticPadTemplate gst_rtp_g726_depay_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-rtp, "
"media = (string) \"audio\", "
"payload = (int) " GST_RTP_PAYLOAD_DYNAMIC_STRING ", "
"encoding-name = (string) { \"G726\", \"G726-16\", \"G726-24\", \"G726-32\", \"G726-40\", "
"\"AAL2-G726-16\", \"AAL2-G726-24\", \"AAL2-G726-32\", \"AAL2-G726-40\" }, "
"clock-rate = (int) 8000;")
);
static GstStaticPadTemplate gst_rtp_g726_depay_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-adpcm, "
"channels = (int) 1, "
"rate = (int) 8000, "
"bitrate = (int) { 16000, 24000, 32000, 40000 }, "
"layout = (string) \"g726\"")
);
static void gst_rtp_g726_depay_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_rtp_g726_depay_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static GstBuffer *gst_rtp_g726_depay_process (GstRTPBaseDepayload * depayload,
GstBuffer * buf);
static gboolean gst_rtp_g726_depay_setcaps (GstRTPBaseDepayload * depayload,
GstCaps * caps);
#define gst_rtp_g726_depay_parent_class parent_class
G_DEFINE_TYPE (GstRtpG726Depay, gst_rtp_g726_depay,
GST_TYPE_RTP_BASE_DEPAYLOAD);
static void
gst_rtp_g726_depay_class_init (GstRtpG726DepayClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
GstRTPBaseDepayloadClass *gstrtpbasedepayload_class;
GST_DEBUG_CATEGORY_INIT (rtpg726depay_debug, "rtpg726depay", 0,
"G.726 RTP Depayloader");
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
gstrtpbasedepayload_class = (GstRTPBaseDepayloadClass *) klass;
gobject_class->set_property = gst_rtp_g726_depay_set_property;
gobject_class->get_property = gst_rtp_g726_depay_get_property;
g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_FORCE_AAL2,
g_param_spec_boolean ("force-aal2", "Force AAL2",
"Force AAL2 decoding for compatibility with bad payloaders",
DEFAULT_FORCE_AAL2, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&gst_rtp_g726_depay_src_template));
gst_element_class_add_pad_template (gstelement_class,
gst_static_pad_template_get (&gst_rtp_g726_depay_sink_template));
gst_element_class_set_static_metadata (gstelement_class,
"RTP G.726 depayloader", "Codec/Depayloader/Network/RTP",
"Extracts G.726 audio from RTP packets",
"Axis Communications <dev-gstreamer@axis.com>");
gstrtpbasedepayload_class->process = gst_rtp_g726_depay_process;
gstrtpbasedepayload_class->set_caps = gst_rtp_g726_depay_setcaps;
}
static void
gst_rtp_g726_depay_init (GstRtpG726Depay * rtpG726depay)
{
GstRTPBaseDepayload *depayload;
depayload = GST_RTP_BASE_DEPAYLOAD (rtpG726depay);
gst_pad_use_fixed_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (depayload));
rtpG726depay->force_aal2 = DEFAULT_FORCE_AAL2;
}
static gboolean
gst_rtp_g726_depay_setcaps (GstRTPBaseDepayload * depayload, GstCaps * caps)
{
GstCaps *srccaps;
GstStructure *structure;
gboolean ret;
gint clock_rate;
const gchar *encoding_name;
GstRtpG726Depay *depay;
depay = GST_RTP_G726_DEPAY (depayload);
structure = gst_caps_get_structure (caps, 0);
if (!gst_structure_get_int (structure, "clock-rate", &clock_rate))
clock_rate = 8000; /* default */
depayload->clock_rate = clock_rate;
depay->aal2 = FALSE;
encoding_name = gst_structure_get_string (structure, "encoding-name");
if (encoding_name == NULL || g_ascii_strcasecmp (encoding_name, "G726") == 0) {
depay->bitrate = DEFAULT_BIT_RATE;
} else {
if (g_str_has_prefix (encoding_name, "AAL2-")) {
depay->aal2 = TRUE;
encoding_name += 5;
}
if (g_ascii_strcasecmp (encoding_name, "G726-16") == 0) {
depay->bitrate = 16000;
} else if (g_ascii_strcasecmp (encoding_name, "G726-24") == 0) {
depay->bitrate = 24000;
} else if (g_ascii_strcasecmp (encoding_name, "G726-32") == 0) {
depay->bitrate = 32000;
} else if (g_ascii_strcasecmp (encoding_name, "G726-40") == 0) {
depay->bitrate = 40000;
} else
goto unknown_encoding;
}
GST_DEBUG ("RTP G.726 depayloader, bitrate set to %d\n", depay->bitrate);
srccaps = gst_caps_new_simple ("audio/x-adpcm",
"channels", G_TYPE_INT, 1,
"rate", G_TYPE_INT, clock_rate,
"bitrate", G_TYPE_INT, depay->bitrate,
"layout", G_TYPE_STRING, LAYOUT_G726, NULL);
ret = gst_pad_set_caps (GST_RTP_BASE_DEPAYLOAD_SRCPAD (depayload), srccaps);
gst_caps_unref (srccaps);
return ret;
/* ERRORS */
unknown_encoding:
{
GST_WARNING ("Could not determine bitrate from encoding-name (%s)",
encoding_name);
return FALSE;
}
}
static GstBuffer *
gst_rtp_g726_depay_process (GstRTPBaseDepayload * depayload, GstBuffer * buf)
{
GstRtpG726Depay *depay;
GstBuffer *outbuf = NULL;
gboolean marker;
GstRTPBuffer rtp = { NULL };
depay = GST_RTP_G726_DEPAY (depayload);
gst_rtp_buffer_map (buf, GST_MAP_READWRITE, &rtp);
marker = gst_rtp_buffer_get_marker (&rtp);
GST_DEBUG ("process : got %" G_GSIZE_FORMAT " bytes, mark %d ts %u seqn %d",
gst_buffer_get_size (buf), marker,
gst_rtp_buffer_get_timestamp (&rtp), gst_rtp_buffer_get_seq (&rtp));
if (depay->aal2 || depay->force_aal2) {
/* AAL2, we can just copy the bytes */
outbuf = gst_rtp_buffer_get_payload_buffer (&rtp);
if (!outbuf)
goto bad_len;
} else {
guint8 *in, *out, tmp;
guint len;
GstMapInfo map;
in = gst_rtp_buffer_get_payload (&rtp);
len = gst_rtp_buffer_get_payload_len (&rtp);
outbuf = gst_rtp_buffer_get_payload_buffer (&rtp);
if (!outbuf)
goto bad_len;
outbuf = gst_buffer_make_writable (outbuf);
gst_buffer_map (outbuf, &map, GST_MAP_WRITE);
out = map.data;
/* we need to reshuffle the bytes, input is always of the form
* A B C D ... with the number of bits depending on the bitrate. */
switch (depay->bitrate) {
case 16000:
{
/* 0
* 0 1 2 3 4 5 6 7
* +-+-+-+-+-+-+-+-+-
* |D D|C C|B B|A A| ...
* |0 1|0 1|0 1|0 1|
* +-+-+-+-+-+-+-+-+-
*/
while (len > 0) {
tmp = *in++;
*out++ = ((tmp & 0xc0) >> 6) |
((tmp & 0x30) >> 2) | ((tmp & 0x0c) << 2) | ((tmp & 0x03) << 6);
len--;
}
break;
}
case 24000:
{
/* 0 1 2
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
* |C C|B B B|A A A|F|E E E|D D D|C|H H H|G G G|F F| ...
* |1 2|0 1 2|0 1 2|2|0 1 2|0 1 2|0|0 1 2|0 1 2|0 1|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
*/
while (len > 2) {
tmp = *in++;
*out++ = ((tmp & 0xe0) >> 5) |
((tmp & 0x1c) << 1) | ((tmp & 0x03) << 6);
tmp = *in++;
*out++ = ((tmp & 0x80) >> 7) |
((tmp & 0x70) >> 3) | ((tmp & 0x0e) << 4) | ((tmp & 0x01) << 7);
tmp = *in++;
*out++ = ((tmp & 0xc0) >> 6) |
((tmp & 0x38) >> 1) | ((tmp & 0x07) << 5);
len -= 3;
}
break;
}
case 32000:
{
/* 0 1
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
* |B B B B|A A A A|D D D D|C C C C| ...
* |0 1 2 3|0 1 2 3|0 1 2 3|0 1 2 3|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
*/
while (len > 0) {
tmp = *in++;
*out++ = ((tmp & 0xf0) >> 4) | ((tmp & 0x0f) << 4);
len--;
}
break;
}
case 40000:
{
/* 0 1 2 3 4
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
* |B B B|A A A A A|D|C C C C C|B B|E E E E|D D D D|G G|F F F F F|E|H H H H H|G G G|
* |2 3 4|0 1 2 3 4|4|0 1 2 3 4|0 1|1 2 3 4|0 1 2 3|3 4|0 1 2 3 4|0|0 1 2 3 4|0 1 2|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
*/
while (len > 4) {
tmp = *in++;
*out++ = ((tmp & 0xf8) >> 3) | ((tmp & 0x07) << 5);
tmp = *in++;
*out++ = ((tmp & 0xc0) >> 6) |
((tmp & 0x3e) << 1) | ((tmp & 0x01) << 7);
tmp = *in++;
*out++ = ((tmp & 0xf0) >> 4) | ((tmp & 0x0f) << 4);
tmp = *in++;
*out++ = ((tmp & 0x80) >> 7) |
((tmp & 0x7c) >> 1) | ((tmp & 0x03) << 6);
tmp = *in++;
*out++ = ((tmp & 0xe0) >> 5) | ((tmp & 0x1f) << 3);
len -= 5;
}
break;
}
}
gst_buffer_unmap (outbuf, &map);
}
if (marker) {
/* mark start of talkspurt with discont */
GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DISCONT);
}
return outbuf;
bad_len:
return NULL;
}
static void
gst_rtp_g726_depay_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstRtpG726Depay *rtpg726depay;
rtpg726depay = GST_RTP_G726_DEPAY (object);
switch (prop_id) {
case PROP_FORCE_AAL2:
rtpg726depay->force_aal2 = g_value_get_boolean (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_rtp_g726_depay_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstRtpG726Depay *rtpg726depay;
rtpg726depay = GST_RTP_G726_DEPAY (object);
switch (prop_id) {
case PROP_FORCE_AAL2:
g_value_set_boolean (value, rtpg726depay->force_aal2);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
gboolean
gst_rtp_g726_depay_plugin_init (GstPlugin * plugin)
{
return gst_element_register (plugin, "rtpg726depay",
GST_RANK_SECONDARY, GST_TYPE_RTP_G726_DEPAY);
}