gstreamer/gst/law/mulaw-encode.c

289 lines
7.8 KiB
C

/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-mulawenc
*
* This element encode mulaw audio. Mulaw coding is also known as G.711.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include "mulaw-encode.h"
#include "mulaw-conversion.h"
extern GstStaticPadTemplate mulaw_enc_src_factory;
extern GstStaticPadTemplate mulaw_enc_sink_factory;
/* Stereo signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
enum
{
ARG_0
};
static void gst_mulawenc_class_init (GstMuLawEncClass * klass);
static void gst_mulawenc_base_init (GstMuLawEncClass * klass);
static void gst_mulawenc_init (GstMuLawEnc * mulawenc);
static GstFlowReturn gst_mulawenc_chain (GstPad * pad, GstBuffer * buffer);
static GstElementClass *parent_class = NULL;
/*static guint gst_stereo_signals[LAST_SIGNAL] = { 0 }; */
static GstCaps *
mulawenc_getcaps (GstPad * pad)
{
GstMuLawEnc *mulawenc;
GstPad *otherpad;
GstCaps *base_caps, *othercaps;
mulawenc = GST_MULAWENC (GST_PAD_PARENT (pad));
base_caps = gst_caps_copy (gst_pad_get_pad_template_caps (pad));
if (pad == mulawenc->srcpad) {
otherpad = mulawenc->sinkpad;
} else {
otherpad = mulawenc->srcpad;
}
othercaps = gst_pad_peer_get_caps (otherpad);
if (othercaps) {
GstStructure *structure;
const GValue *orate, *ochans;
const GValue *rate, *chans;
GValue irate = { 0 };
GValue ichans = { 0 };
if (gst_caps_is_empty (othercaps) || gst_caps_is_any (othercaps))
goto done;
structure = gst_caps_get_structure (othercaps, 0);
orate = gst_structure_get_value (structure, "rate");
ochans = gst_structure_get_value (structure, "channels");
structure = gst_caps_get_structure (base_caps, 0);
rate = gst_structure_get_value (structure, "rate");
chans = gst_structure_get_value (structure, "channels");
if (orate) {
gst_value_intersect (&irate, orate, rate);
gst_structure_set_value (structure, "rate", &irate);
}
if (ochans) {
gst_value_intersect (&ichans, ochans, chans);
gst_structure_set_value (structure, "channels", &ichans);
}
done:
gst_caps_unref (othercaps);
}
return base_caps;
}
static gboolean
mulawenc_setcaps (GstPad * pad, GstCaps * caps)
{
GstMuLawEnc *mulawenc;
GstPad *otherpad;
GstStructure *structure;
GstCaps *base_caps;
mulawenc = GST_MULAWENC (gst_pad_get_parent (pad));
structure = gst_caps_get_structure (caps, 0);
gst_structure_get_int (structure, "channels", &mulawenc->channels);
gst_structure_get_int (structure, "rate", &mulawenc->rate);
if (pad == mulawenc->sinkpad) {
otherpad = mulawenc->srcpad;
} else {
otherpad = mulawenc->sinkpad;
}
base_caps = gst_caps_copy (gst_pad_get_pad_template_caps (otherpad));
structure = gst_caps_get_structure (base_caps, 0);
gst_structure_set (structure, "rate", G_TYPE_INT, mulawenc->rate, NULL);
gst_structure_set (structure, "channels", G_TYPE_INT, mulawenc->channels,
NULL);
gst_pad_set_caps (otherpad, base_caps);
gst_object_unref (mulawenc);
gst_caps_unref (base_caps);
return TRUE;
}
GType
gst_mulawenc_get_type (void)
{
static GType mulawenc_type = 0;
if (!mulawenc_type) {
static const GTypeInfo mulawenc_info = {
sizeof (GstMuLawEncClass),
(GBaseInitFunc) gst_mulawenc_base_init,
NULL,
(GClassInitFunc) gst_mulawenc_class_init,
NULL,
NULL,
sizeof (GstMuLawEnc),
0,
(GInstanceInitFunc) gst_mulawenc_init,
};
mulawenc_type =
g_type_register_static (GST_TYPE_ELEMENT, "GstMuLawEnc", &mulawenc_info,
0);
}
return mulawenc_type;
}
static void
gst_mulawenc_base_init (GstMuLawEncClass * klass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
const GstElementDetails mulawenc_details =
GST_ELEMENT_DETAILS ("Mu Law audio encoder",
"Codec/Encoder/Audio",
"Convert 16bit PCM to 8bit mu law",
"Zaheer Abbas Merali <zaheerabbas at merali dot org>");
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&mulaw_enc_src_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&mulaw_enc_sink_factory));
gst_element_class_set_details (element_class, &mulawenc_details);
}
static void
gst_mulawenc_class_init (GstMuLawEncClass * klass)
{
parent_class = g_type_class_peek_parent (klass);
}
static void
gst_mulawenc_init (GstMuLawEnc * mulawenc)
{
mulawenc->sinkpad =
gst_pad_new_from_static_template (&mulaw_enc_sink_factory, "sink");
gst_pad_set_setcaps_function (mulawenc->sinkpad, mulawenc_setcaps);
gst_pad_set_getcaps_function (mulawenc->sinkpad, mulawenc_getcaps);
gst_pad_set_chain_function (mulawenc->sinkpad, gst_mulawenc_chain);
gst_element_add_pad (GST_ELEMENT (mulawenc), mulawenc->sinkpad);
mulawenc->srcpad =
gst_pad_new_from_static_template (&mulaw_enc_src_factory, "src");
gst_pad_set_setcaps_function (mulawenc->srcpad, mulawenc_setcaps);
gst_pad_set_getcaps_function (mulawenc->srcpad, mulawenc_getcaps);
gst_pad_use_fixed_caps (mulawenc->srcpad);
gst_element_add_pad (GST_ELEMENT (mulawenc), mulawenc->srcpad);
/* init rest */
mulawenc->channels = 0;
mulawenc->rate = 0;
}
static GstFlowReturn
gst_mulawenc_chain (GstPad * pad, GstBuffer * buffer)
{
GstMuLawEnc *mulawenc;
gint16 *linear_data;
guint linear_size;
guint8 *mulaw_data;
guint mulaw_size;
GstBuffer *outbuf;
GstFlowReturn ret;
GstClockTime timestamp, duration;
mulawenc = GST_MULAWENC (gst_pad_get_parent (pad));
if (!mulawenc->rate || !mulawenc->channels)
goto not_negotiated;
linear_data = (gint16 *) GST_BUFFER_DATA (buffer);
linear_size = GST_BUFFER_SIZE (buffer);
mulaw_size = linear_size / 2;
timestamp = GST_BUFFER_TIMESTAMP (buffer);
duration = GST_BUFFER_DURATION (buffer);
ret = gst_pad_alloc_buffer_and_set_caps (mulawenc->srcpad,
GST_BUFFER_OFFSET_NONE, mulaw_size, GST_PAD_CAPS (mulawenc->srcpad),
&outbuf);
if (ret != GST_FLOW_OK)
goto alloc_failed;
if (duration == -1) {
duration = gst_util_uint64_scale_int (mulaw_size,
GST_SECOND, mulawenc->rate * mulawenc->channels);
}
if (GST_BUFFER_SIZE (outbuf) < mulaw_size) {
/* pad-alloc can suggest a smaller size */
gst_buffer_unref (outbuf);
outbuf = gst_buffer_new_and_alloc (mulaw_size);
}
mulaw_data = (guint8 *) GST_BUFFER_DATA (outbuf);
/* copy discont flag */
if (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DISCONT))
GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DISCONT);
GST_BUFFER_TIMESTAMP (outbuf) = timestamp;
GST_BUFFER_DURATION (outbuf) = duration;
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (mulawenc->srcpad));
mulaw_encode (linear_data, mulaw_data, mulaw_size);
gst_buffer_unref (buffer);
ret = gst_pad_push (mulawenc->srcpad, outbuf);
done:
gst_object_unref (mulawenc);
return ret;
not_negotiated:
{
GST_DEBUG_OBJECT (mulawenc, "no format negotiated");
ret = GST_FLOW_NOT_NEGOTIATED;
gst_buffer_unref (buffer);
goto done;
}
alloc_failed:
{
GST_DEBUG_OBJECT (mulawenc, "pad alloc failed");
gst_buffer_unref (buffer);
goto done;
}
}