gstreamer/gst/law/mulaw-decode.c
Stefan Kost a99d3f8769 Update and add documentation for plugins with no deps (gst).
Link to properties. Correct titles for examples. Document a few trivial cases. Keep lists in section file and docs/plugins/Makefile.am alphabetically ordered.
2009-01-28 12:32:59 +02:00

245 lines
6.7 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-mulawdec
*
* This element decodes mulaw audio. Mulaw coding is also known as G.711.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include "mulaw-decode.h"
#include "mulaw-conversion.h"
extern GstStaticPadTemplate mulaw_dec_src_factory;
extern GstStaticPadTemplate mulaw_dec_sink_factory;
/* Stereo signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
enum
{
ARG_0
};
static void gst_mulawdec_class_init (GstMuLawDecClass * klass);
static void gst_mulawdec_base_init (GstMuLawDecClass * klass);
static void gst_mulawdec_init (GstMuLawDec * mulawdec);
static GstStateChangeReturn
gst_mulawdec_change_state (GstElement * element, GstStateChange transition);
static GstFlowReturn gst_mulawdec_chain (GstPad * pad, GstBuffer * buffer);
static GstElementClass *parent_class = NULL;
static gboolean
mulawdec_sink_setcaps (GstPad * pad, GstCaps * caps)
{
GstMuLawDec *mulawdec;
GstStructure *structure;
int rate, channels;
gboolean ret;
GstCaps *outcaps;
mulawdec = GST_MULAWDEC (GST_PAD_PARENT (pad));
structure = gst_caps_get_structure (caps, 0);
ret = gst_structure_get_int (structure, "rate", &rate);
ret = ret && gst_structure_get_int (structure, "channels", &channels);
if (!ret)
return FALSE;
outcaps = gst_caps_new_simple ("audio/x-raw-int",
"width", G_TYPE_INT, 16,
"depth", G_TYPE_INT, 16,
"endianness", G_TYPE_INT, G_BYTE_ORDER,
"signed", G_TYPE_BOOLEAN, TRUE,
"rate", G_TYPE_INT, rate, "channels", G_TYPE_INT, channels, NULL);
ret = gst_pad_set_caps (mulawdec->srcpad, outcaps);
gst_caps_unref (outcaps);
if (ret) {
GST_DEBUG_OBJECT (mulawdec, "rate=%d, channels=%d", rate, channels);
mulawdec->rate = rate;
mulawdec->channels = channels;
}
return ret;
}
GType
gst_mulawdec_get_type (void)
{
static GType mulawdec_type = 0;
if (!mulawdec_type) {
static const GTypeInfo mulawdec_info = {
sizeof (GstMuLawDecClass),
(GBaseInitFunc) gst_mulawdec_base_init,
NULL,
(GClassInitFunc) gst_mulawdec_class_init,
NULL,
NULL,
sizeof (GstMuLawDec),
0,
(GInstanceInitFunc) gst_mulawdec_init,
};
mulawdec_type =
g_type_register_static (GST_TYPE_ELEMENT, "GstMuLawDec", &mulawdec_info,
0);
}
return mulawdec_type;
}
static void
gst_mulawdec_base_init (GstMuLawDecClass * klass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
const GstElementDetails mulawdec_details =
GST_ELEMENT_DETAILS ("Mu Law audio decoder",
"Codec/Decoder/Audio",
"Convert 8bit mu law to 16bit PCM",
"Zaheer Abbas Merali <zaheerabbas at merali dot org>");
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&mulaw_dec_src_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&mulaw_dec_sink_factory));
gst_element_class_set_details (element_class, &mulawdec_details);
}
static void
gst_mulawdec_class_init (GstMuLawDecClass * klass)
{
GstElementClass *element_class = (GstElementClass *) klass;
parent_class = g_type_class_peek_parent (klass);
element_class->change_state = GST_DEBUG_FUNCPTR (gst_mulawdec_change_state);
}
static void
gst_mulawdec_init (GstMuLawDec * mulawdec)
{
mulawdec->sinkpad =
gst_pad_new_from_static_template (&mulaw_dec_sink_factory, "sink");
gst_pad_set_setcaps_function (mulawdec->sinkpad, mulawdec_sink_setcaps);
gst_pad_set_chain_function (mulawdec->sinkpad, gst_mulawdec_chain);
gst_element_add_pad (GST_ELEMENT (mulawdec), mulawdec->sinkpad);
mulawdec->srcpad =
gst_pad_new_from_static_template (&mulaw_dec_src_factory, "src");
gst_pad_use_fixed_caps (mulawdec->srcpad);
gst_element_add_pad (GST_ELEMENT (mulawdec), mulawdec->srcpad);
}
static GstFlowReturn
gst_mulawdec_chain (GstPad * pad, GstBuffer * buffer)
{
GstMuLawDec *mulawdec;
gint16 *linear_data;
guint8 *mulaw_data;
guint mulaw_size;
GstBuffer *outbuf;
GstFlowReturn ret;
mulawdec = GST_MULAWDEC (GST_PAD_PARENT (pad));
if (G_UNLIKELY (mulawdec->rate == 0))
goto not_negotiated;
mulaw_data = (guint8 *) GST_BUFFER_DATA (buffer);
mulaw_size = GST_BUFFER_SIZE (buffer);
ret =
gst_pad_alloc_buffer_and_set_caps (mulawdec->srcpad,
GST_BUFFER_OFFSET_NONE, mulaw_size * 2, GST_PAD_CAPS (mulawdec->srcpad),
&outbuf);
if (ret != GST_FLOW_OK)
goto alloc_failed;
linear_data = (gint16 *) 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) = GST_BUFFER_TIMESTAMP (buffer);
if (GST_BUFFER_DURATION (outbuf) == GST_CLOCK_TIME_NONE)
GST_BUFFER_DURATION (outbuf) = gst_util_uint64_scale_int (GST_SECOND,
mulaw_size * 2, 2 * mulawdec->rate * mulawdec->channels);
else
GST_BUFFER_DURATION (outbuf) = GST_BUFFER_DURATION (buffer);
gst_buffer_set_caps (outbuf, GST_PAD_CAPS (mulawdec->srcpad));
mulaw_decode (mulaw_data, linear_data, mulaw_size);
gst_buffer_unref (buffer);
ret = gst_pad_push (mulawdec->srcpad, outbuf);
return ret;
/* ERRORS */
not_negotiated:
{
GST_ERROR_OBJECT (mulawdec, "no format negotiated");
gst_buffer_unref (buffer);
return GST_FLOW_NOT_NEGOTIATED;
}
alloc_failed:
{
GST_ERROR_OBJECT (mulawdec, "pad alloc failed");
gst_buffer_unref (buffer);
return ret;
}
}
static GstStateChangeReturn
gst_mulawdec_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret;
GstMuLawDec *dec = GST_MULAWDEC (element);
switch (transition) {
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
if (ret != GST_STATE_CHANGE_SUCCESS)
return ret;
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
dec->rate = 0;
dec->channels = 0;
break;
default:
break;
}
return ret;
}