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/* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, 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;
static gboolean gst_mulawdec_set_format (GstAudioDecoder * dec, GstCaps * caps);
static GstFlowReturn gst_mulawdec_handle_frame (GstAudioDecoder * dec,
GstBuffer * buffer);
/* Stereo signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
enum
{
PROP_0
};
#define gst_mulawdec_parent_class parent_class
G_DEFINE_TYPE (GstMuLawDec, gst_mulawdec, GST_TYPE_AUDIO_DECODER);
static gboolean
gst_mulawdec_set_format (GstAudioDecoder * dec, GstCaps * caps)
{
GstMuLawDec *mulawdec = GST_MULAWDEC (dec);
GstStructure *structure;
int rate, channels;
GstAudioInfo info;
structure = gst_caps_get_structure (caps, 0);
if (!structure) {
GST_ERROR ("failed to get structure from caps");
goto error_failed_get_structure;
}
if (!gst_structure_get_int (structure, "rate", &rate)) {
GST_ERROR ("failed to find field rate in input caps");
goto error_failed_find_rate;
}
if (!gst_structure_get_int (structure, "channels", &channels)) {
GST_ERROR ("failed to find field channels in input caps");
goto error_failed_find_channel;
}
gst_audio_info_init (&info);
gst_audio_info_set_format (&info, GST_AUDIO_FORMAT_S16, rate, channels, NULL);
GST_DEBUG_OBJECT (mulawdec, "rate=%d, channels=%d", rate, channels);
return gst_audio_decoder_set_output_format (dec, &info);
error_failed_find_channel:
error_failed_find_rate:
error_failed_get_structure:
return FALSE;
}
static GstFlowReturn
gst_mulawdec_handle_frame (GstAudioDecoder * dec, GstBuffer * buffer)
{
GstMapInfo inmap, outmap;
gint16 *linear_data;
guint8 *mulaw_data;
gsize mulaw_size, linear_size;
GstBuffer *outbuf;
if (!buffer) {
return GST_FLOW_OK;
}
if (!gst_buffer_map (buffer, &inmap, GST_MAP_READ)) {
GST_ERROR ("failed to map input buffer");
goto error_failed_map_input_buffer;
}
mulaw_data = inmap.data;
mulaw_size = inmap.size;
linear_size = mulaw_size * 2;
outbuf = gst_audio_decoder_allocate_output_buffer (dec, linear_size);
if (!gst_buffer_map (outbuf, &outmap, GST_MAP_WRITE)) {
GST_ERROR ("failed to map input buffer");
goto error_failed_map_output_buffer;
}
linear_data = (gint16 *) outmap.data;
mulaw_decode (mulaw_data, linear_data, mulaw_size);
gst_buffer_unmap (outbuf, &outmap);
gst_buffer_unmap (buffer, &inmap);
return gst_audio_decoder_finish_frame (dec, outbuf, -1);
error_failed_map_output_buffer:
gst_buffer_unref (outbuf);
gst_buffer_unmap (buffer, &inmap);
error_failed_map_input_buffer:
return GST_FLOW_ERROR;
}
static gboolean
gst_mulawdec_start (GstAudioDecoder * dec)
{
gst_audio_decoder_set_estimate_rate (dec, TRUE);
return TRUE;
}
static void
gst_mulawdec_class_init (GstMuLawDecClass * klass)
{
GstElementClass *element_class = (GstElementClass *) klass;
GstAudioDecoderClass *audiodec_class = GST_AUDIO_DECODER_CLASS (klass);
gst_element_class_add_static_pad_template (element_class,
&mulaw_dec_src_factory);
gst_element_class_add_static_pad_template (element_class,
&mulaw_dec_sink_factory);
audiodec_class->start = GST_DEBUG_FUNCPTR (gst_mulawdec_start);
audiodec_class->set_format = GST_DEBUG_FUNCPTR (gst_mulawdec_set_format);
audiodec_class->handle_frame = GST_DEBUG_FUNCPTR (gst_mulawdec_handle_frame);
gst_element_class_set_static_metadata (element_class, "Mu Law audio decoder",
"Codec/Decoder/Audio",
"Convert 8bit mu law to 16bit PCM",
"Zaheer Abbas Merali <zaheerabbas at merali dot org>");
}
static void
gst_mulawdec_init (GstMuLawDec * mulawdec)
{
gst_audio_decoder_set_needs_format (GST_AUDIO_DECODER (mulawdec), TRUE);
gst_audio_decoder_set_use_default_pad_acceptcaps (GST_AUDIO_DECODER_CAST
(mulawdec), TRUE);
GST_PAD_SET_ACCEPT_TEMPLATE (GST_AUDIO_DECODER_SINK_PAD (mulawdec));
}
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