gstreamer/gst/siren/gstsirendec.c

256 lines
7.1 KiB
C

/*
* Siren Decoder Gst Element
*
* @author: Youness Alaoui <kakaroto@kakaroto.homelinux.net>
*
* 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-sirendec
*
* This decodes audio buffers from the Siren 16 codec (a 16khz extension of
* G.722.1) that is meant to be compatible with the Microsoft Windows Live
* Messenger(tm) implementation.
*
* Ref: http://www.polycom.com/company/about_us/technology/siren_g7221/index.html
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstsirendec.h"
#include <string.h>
GST_DEBUG_CATEGORY (sirendec_debug);
#define GST_CAT_DEFAULT (sirendec_debug)
#define FRAME_DURATION (20 * GST_MSECOND)
static GstStaticPadTemplate sinktemplate = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-siren, " "dct-length = (int) 320"));
static GstStaticPadTemplate srctemplate = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-raw, format = (string) \"S16LE\", "
"rate = (int) 16000, " "channels = (int) 1"));
static gboolean gst_siren_dec_start (GstAudioDecoder * dec);
static gboolean gst_siren_dec_stop (GstAudioDecoder * dec);
static gboolean gst_siren_dec_set_format (GstAudioDecoder * dec,
GstCaps * caps);
static gboolean gst_siren_dec_parse (GstAudioDecoder * dec,
GstAdapter * adapter, gint * offset, gint * length);
static GstFlowReturn gst_siren_dec_handle_frame (GstAudioDecoder * dec,
GstBuffer * buffer);
G_DEFINE_TYPE (GstSirenDec, gst_siren_dec, GST_TYPE_AUDIO_DECODER);
static void
gst_siren_dec_class_init (GstSirenDecClass * klass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
GstAudioDecoderClass *base_class = GST_AUDIO_DECODER_CLASS (klass);
GST_DEBUG_CATEGORY_INIT (sirendec_debug, "sirendec", 0, "sirendec");
gst_element_class_add_static_pad_template (element_class, &srctemplate);
gst_element_class_add_static_pad_template (element_class, &sinktemplate);
gst_element_class_set_static_metadata (element_class, "Siren Decoder element",
"Codec/Decoder/Audio ",
"Decode streams encoded with the Siren7 codec into 16bit PCM",
"Youness Alaoui <kakaroto@kakaroto.homelinux.net>");
base_class->start = GST_DEBUG_FUNCPTR (gst_siren_dec_start);
base_class->stop = GST_DEBUG_FUNCPTR (gst_siren_dec_stop);
base_class->set_format = GST_DEBUG_FUNCPTR (gst_siren_dec_set_format);
base_class->parse = GST_DEBUG_FUNCPTR (gst_siren_dec_parse);
base_class->handle_frame = GST_DEBUG_FUNCPTR (gst_siren_dec_handle_frame);
GST_DEBUG ("Class Init done");
}
static void
gst_siren_dec_init (GstSirenDec * dec)
{
gst_audio_decoder_set_needs_format (GST_AUDIO_DECODER (dec), TRUE);
gst_audio_decoder_set_use_default_pad_acceptcaps (GST_AUDIO_DECODER_CAST
(dec), TRUE);
GST_PAD_SET_ACCEPT_TEMPLATE (GST_AUDIO_DECODER_SINK_PAD (dec));
}
static gboolean
gst_siren_dec_start (GstAudioDecoder * dec)
{
GstSirenDec *sdec = GST_SIREN_DEC (dec);
GST_DEBUG_OBJECT (dec, "start");
sdec->decoder = Siren7_NewDecoder (16000);
/* no flushing please */
gst_audio_decoder_set_drainable (dec, FALSE);
return TRUE;
}
static gboolean
gst_siren_dec_stop (GstAudioDecoder * dec)
{
GstSirenDec *sdec = GST_SIREN_DEC (dec);
GST_DEBUG_OBJECT (dec, "stop");
Siren7_CloseDecoder (sdec->decoder);
return TRUE;
}
static gboolean
gst_siren_dec_set_format (GstAudioDecoder * bdec, GstCaps * caps)
{
GstAudioInfo info;
gst_audio_info_init (&info);
gst_audio_info_set_format (&info, GST_AUDIO_FORMAT_S16LE, 16000, 1, NULL);
return gst_audio_decoder_set_output_format (bdec, &info);
}
static GstFlowReturn
gst_siren_dec_parse (GstAudioDecoder * dec, GstAdapter * adapter,
gint * offset, gint * length)
{
gint size;
GstFlowReturn ret;
size = gst_adapter_available (adapter);
g_return_val_if_fail (size > 0, GST_FLOW_ERROR);
/* accept any multiple of frames */
if (size > 40) {
ret = GST_FLOW_OK;
*offset = 0;
*length = size - (size % 40);
} else {
ret = GST_FLOW_EOS;
}
return ret;
}
static GstFlowReturn
gst_siren_dec_handle_frame (GstAudioDecoder * bdec, GstBuffer * buf)
{
GstSirenDec *dec;
GstFlowReturn ret = GST_FLOW_OK;
GstBuffer *out_buf;
guint8 *in_data, *out_data;
guint i, size, num_frames;
gint out_size;
#ifndef GST_DISABLE_GST_DEBUG
gint in_size;
#endif
gint decode_ret;
GstMapInfo inmap, outmap;
dec = GST_SIREN_DEC (bdec);
size = gst_buffer_get_size (buf);
GST_LOG_OBJECT (dec, "Received buffer of size %u", size);
g_return_val_if_fail (size % 40 == 0, GST_FLOW_ERROR);
g_return_val_if_fail (size > 0, GST_FLOW_ERROR);
/* process 40 input bytes into 640 output bytes */
num_frames = size / 40;
/* this is the input/output size */
#ifndef GST_DISABLE_GST_DEBUG
in_size = num_frames * 40;
#endif
out_size = num_frames * 640;
GST_LOG_OBJECT (dec, "we have %u frames, %u in, %u out", num_frames, in_size,
out_size);
out_buf = gst_audio_decoder_allocate_output_buffer (bdec, out_size);
if (out_buf == NULL)
goto alloc_failed;
/* get the input data for all the frames */
gst_buffer_map (buf, &inmap, GST_MAP_READ);
gst_buffer_map (out_buf, &outmap, GST_MAP_WRITE);
in_data = inmap.data;
out_data = outmap.data;
for (i = 0; i < num_frames; i++) {
GST_LOG_OBJECT (dec, "Decoding frame %u/%u", i, num_frames);
/* decode 40 input bytes to 640 output bytes */
decode_ret = Siren7_DecodeFrame (dec->decoder, in_data, out_data);
if (decode_ret != 0)
goto decode_error;
/* move to next frame */
out_data += 640;
in_data += 40;
}
gst_buffer_unmap (buf, &inmap);
gst_buffer_unmap (out_buf, &outmap);
GST_LOG_OBJECT (dec, "Finished decoding");
/* might really be multiple frames,
* but was treated as one for all purposes here */
ret = gst_audio_decoder_finish_frame (bdec, out_buf, 1);
done:
return ret;
/* ERRORS */
alloc_failed:
{
GST_DEBUG_OBJECT (dec, "failed to pad_alloc buffer: %d (%s)", ret,
gst_flow_get_name (ret));
goto done;
}
decode_error:
{
GST_AUDIO_DECODER_ERROR (bdec, 1, STREAM, DECODE, (NULL),
("Error decoding frame: %d", decode_ret), ret);
if (ret == GST_FLOW_OK)
gst_audio_decoder_finish_frame (bdec, NULL, 1);
gst_buffer_unref (out_buf);
goto done;
}
}
gboolean
gst_siren_dec_plugin_init (GstPlugin * plugin)
{
return gst_element_register (plugin, "sirendec",
GST_RANK_MARGINAL, GST_TYPE_SIREN_DEC);
}