gstreamer/ext/sbc/gstsbcenc.c

362 lines
11 KiB
C

/* GStreamer SBC audio encoder
* Copyright (C) 2004-2010 Marcel Holtmann <marcel@holtmann.org>
* Copyright (C) 2013 Tim-Philipp Müller <tim centricular net>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser 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-sbenc
*
* This element encodes raw integer PCM audio into a Bluetooth SBC audio.
*
* Encoding paramets such as blocks, subbands, bitpool, channel-mode, and
* allocation-mode can be set by adding a capsfilter element with appropriate
* filtercaps after the sbcenc encoder element.
*
* <refsect2>
* <title>Example pipelines</title>
* |[
* gst-launch-1.0 -v audiotestsrc ! sbcenc ! rtpsbcpay ! udpsink
* ]| Encode a sine wave into SBC, RTP payload it and send over the network using UDP
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <string.h>
#include "gstsbcenc.h"
GST_DEBUG_CATEGORY_STATIC (sbc_enc_debug);
#define GST_CAT_DEFAULT sbc_enc_debug
G_DEFINE_TYPE (GstSbcEnc, gst_sbc_enc, GST_TYPE_AUDIO_ENCODER);
static GstStaticPadTemplate sbc_enc_sink_factory =
GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-raw, format=" GST_AUDIO_NE (S16) ", "
"rate = (int) { 16000, 32000, 44100, 48000 }, "
"channels = (int) [ 1, 2 ]"));
static GstStaticPadTemplate sbc_enc_src_factory =
GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
GST_STATIC_CAPS ("audio/x-sbc, "
"rate = (int) { 16000, 32000, 44100, 48000 }, "
"channels = (int) [ 1, 2 ], "
"channel-mode = (string) { mono, dual, stereo, joint }, "
"blocks = (int) { 4, 8, 12, 16 }, "
"subbands = (int) { 4, 8 }, "
"allocation-method = (string) { snr, loudness }, "
"bitpool = (int) [ 2, 64 ]"));
static gboolean gst_sbc_enc_start (GstAudioEncoder * enc);
static gboolean gst_sbc_enc_stop (GstAudioEncoder * enc);
static gboolean gst_sbc_enc_set_format (GstAudioEncoder * enc,
GstAudioInfo * info);
static GstFlowReturn gst_sbc_enc_handle_frame (GstAudioEncoder * enc,
GstBuffer * buffer);
static gboolean
gst_sbc_enc_set_format (GstAudioEncoder * audio_enc, GstAudioInfo * info)
{
const gchar *allocation_method, *channel_mode;
GstSbcEnc *enc = GST_SBC_ENC (audio_enc);
GstStructure *s;
GstCaps *caps, *filter_caps;
GstCaps *output_caps;
guint sampleframes_per_frame;
enc->rate = GST_AUDIO_INFO_RATE (info);
enc->channels = GST_AUDIO_INFO_CHANNELS (info);
/* negotiate output format based on downstream caps restrictions */
caps = gst_pad_get_allowed_caps (GST_AUDIO_ENCODER_SRC_PAD (enc));
if (caps == GST_CAPS_NONE || gst_caps_is_empty (caps)) {
gst_caps_unref (caps);
return FALSE;
}
if (caps == NULL)
caps = gst_static_pad_template_get_caps (&sbc_enc_src_factory);
/* fixate output caps */
filter_caps = gst_caps_new_simple ("audio/x-sbc", "rate", G_TYPE_INT,
enc->rate, "channels", G_TYPE_INT, enc->channels, NULL);
output_caps = gst_caps_intersect (caps, filter_caps);
gst_caps_unref (filter_caps);
if (output_caps == NULL || gst_caps_is_empty (output_caps)) {
GST_WARNING_OBJECT (enc, "Couldn't negotiate output caps with input rate "
"%d and input channels %d and allowed output caps %" GST_PTR_FORMAT,
enc->rate, enc->channels, caps);
if (output_caps)
gst_caps_unref (output_caps);
gst_caps_unref (caps);
return FALSE;
}
gst_caps_unref (caps);
caps = NULL;
GST_DEBUG_OBJECT (enc, "fixating caps %" GST_PTR_FORMAT, output_caps);
output_caps = gst_caps_truncate (output_caps);
s = gst_caps_get_structure (output_caps, 0);
if (enc->channels == 1) {
if (!gst_structure_fixate_field_string (s, "channel-mode", "mono")) {
GST_DEBUG_OBJECT (enc, "Failed to fixate channel-mode to mono");
gst_caps_unref (output_caps);
return FALSE;
}
} else {
if (!gst_structure_fixate_field_string (s, "channel-mode", "joint") &&
!gst_structure_fixate_field_string (s, "channel-mode", "stereo") &&
!gst_structure_fixate_field_string (s, "channel-mode", "dual")) {
GST_DEBUG_OBJECT (enc, "Failed to fixate channel-mode for 2 channels");
gst_caps_unref (output_caps);
return FALSE;
}
}
gst_structure_fixate_field_nearest_int (s, "bitpool", 64);
gst_structure_fixate_field_nearest_int (s, "blocks", 16);
gst_structure_fixate_field_nearest_int (s, "subbands", 8);
gst_structure_fixate_field_string (s, "allocation-method", "loudness");
s = NULL;
/* in case there's anything else left to fixate */
output_caps = gst_caps_fixate (output_caps);
gst_caps_set_simple (output_caps, "parsed", G_TYPE_BOOLEAN, TRUE, NULL);
GST_INFO_OBJECT (enc, "output caps %" GST_PTR_FORMAT, output_caps);
/* let's see what we fixated to */
s = gst_caps_get_structure (output_caps, 0);
gst_structure_get_int (s, "blocks", &enc->blocks);
gst_structure_get_int (s, "subbands", &enc->subbands);
gst_structure_get_int (s, "bitpool", &enc->bitpool);
allocation_method = gst_structure_get_string (s, "allocation-method");
channel_mode = gst_structure_get_string (s, "channel-mode");
/* we want to be handed all available samples in handle_frame, but always
* enough to encode a frame */
sampleframes_per_frame = enc->blocks * enc->subbands;
gst_audio_encoder_set_frame_samples_min (audio_enc, sampleframes_per_frame);
gst_audio_encoder_set_frame_samples_max (audio_enc, sampleframes_per_frame);
gst_audio_encoder_set_frame_max (audio_enc, 0);
/* FIXME: what to do with left-over samples at the end? can we encode them? */
gst_audio_encoder_set_hard_min (audio_enc, TRUE);
/* and configure encoder based on the output caps we negotiated */
if (enc->rate == 16000)
enc->sbc.frequency = SBC_FREQ_16000;
else if (enc->rate == 32000)
enc->sbc.frequency = SBC_FREQ_32000;
else if (enc->rate == 44100)
enc->sbc.frequency = SBC_FREQ_44100;
else if (enc->rate == 48000)
enc->sbc.frequency = SBC_FREQ_48000;
else
return FALSE;
if (enc->blocks == 4)
enc->sbc.blocks = SBC_BLK_4;
else if (enc->blocks == 8)
enc->sbc.blocks = SBC_BLK_8;
else if (enc->blocks == 12)
enc->sbc.blocks = SBC_BLK_12;
else if (enc->blocks == 16)
enc->sbc.blocks = SBC_BLK_16;
else
return FALSE;
enc->sbc.subbands = (enc->subbands == 4) ? SBC_SB_4 : SBC_SB_8;
enc->sbc.bitpool = enc->bitpool;
if (channel_mode == NULL || allocation_method == NULL)
return FALSE;
if (strcmp (channel_mode, "joint") == 0)
enc->sbc.mode = SBC_MODE_JOINT_STEREO;
else if (strcmp (channel_mode, "stereo") == 0)
enc->sbc.mode = SBC_MODE_STEREO;
else if (strcmp (channel_mode, "dual") == 0)
enc->sbc.mode = SBC_MODE_DUAL_CHANNEL;
else if (strcmp (channel_mode, "mono") == 0)
enc->sbc.mode = SBC_MODE_MONO;
else if (strcmp (channel_mode, "auto") == 0)
enc->sbc.mode = SBC_MODE_JOINT_STEREO;
else
return FALSE;
if (strcmp (allocation_method, "loudness") == 0)
enc->sbc.allocation = SBC_AM_LOUDNESS;
else if (strcmp (allocation_method, "snr") == 0)
enc->sbc.allocation = SBC_AM_SNR;
else
return FALSE;
if (!gst_audio_encoder_set_output_format (audio_enc, output_caps))
return FALSE;
return gst_audio_encoder_negotiate (audio_enc);
}
static GstFlowReturn
gst_sbc_enc_handle_frame (GstAudioEncoder * audio_enc, GstBuffer * buffer)
{
GstSbcEnc *enc = GST_SBC_ENC (audio_enc);
GstMapInfo in_map, out_map;
GstBuffer *outbuf = NULL;
guint samples_per_frame, frames, i = 0;
/* no fancy draining */
if (buffer == NULL)
return GST_FLOW_OK;
if (G_UNLIKELY (enc->channels == 0 || enc->blocks == 0 || enc->subbands == 0))
return GST_FLOW_NOT_NEGOTIATED;
samples_per_frame = enc->channels * enc->blocks * enc->subbands;
if (!gst_buffer_map (buffer, &in_map, GST_MAP_READ))
goto map_failed;
frames = in_map.size / (samples_per_frame * sizeof (gint16));
GST_LOG_OBJECT (enc,
"encoding %" G_GSIZE_FORMAT " samples into %u SBC frames",
in_map.size / (enc->channels * sizeof (gint16)), frames);
if (frames > 0) {
gsize frame_len;
frame_len = sbc_get_frame_length (&enc->sbc);
outbuf = gst_audio_encoder_allocate_output_buffer (audio_enc,
frames * frame_len);
if (outbuf == NULL)
goto no_buffer;
gst_buffer_map (outbuf, &out_map, GST_MAP_WRITE);
for (i = 0; i < frames; ++i) {
gssize ret, written = 0;
ret = sbc_encode (&enc->sbc, in_map.data + (i * samples_per_frame * 2),
samples_per_frame * 2, out_map.data + (i * frame_len), frame_len,
&written);
if (ret < 0 || written != frame_len) {
GST_WARNING_OBJECT (enc, "encoding error, ret = %" G_GSSIZE_FORMAT ", "
"written = %" G_GSSIZE_FORMAT, ret, written);
break;
}
}
gst_buffer_unmap (outbuf, &out_map);
if (i > 0)
gst_buffer_set_size (outbuf, i * frame_len);
else
gst_buffer_replace (&outbuf, NULL);
}
done:
gst_buffer_unmap (buffer, &in_map);
return gst_audio_encoder_finish_frame (audio_enc, outbuf,
i * (samples_per_frame / enc->channels));
/* ERRORS */
no_buffer:
{
GST_ERROR_OBJECT (enc, "could not allocate output buffer");
goto done;
}
map_failed:
{
GST_ERROR_OBJECT (enc, "could not map input buffer");
goto done;
}
}
static gboolean
gst_sbc_enc_start (GstAudioEncoder * audio_enc)
{
GstSbcEnc *enc = GST_SBC_ENC (audio_enc);
GST_INFO_OBJECT (enc, "Setup subband codec");
sbc_init (&enc->sbc, 0);
return TRUE;
}
static gboolean
gst_sbc_enc_stop (GstAudioEncoder * audio_enc)
{
GstSbcEnc *enc = GST_SBC_ENC (audio_enc);
GST_INFO_OBJECT (enc, "Finish subband codec");
sbc_finish (&enc->sbc);
enc->subbands = 0;
enc->blocks = 0;
enc->rate = 0;
enc->channels = 0;
enc->bitpool = 0;
return TRUE;
}
static void
gst_sbc_enc_class_init (GstSbcEncClass * klass)
{
GstAudioEncoderClass *encoder_class = GST_AUDIO_ENCODER_CLASS (klass);
GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
encoder_class->start = GST_DEBUG_FUNCPTR (gst_sbc_enc_start);
encoder_class->stop = GST_DEBUG_FUNCPTR (gst_sbc_enc_stop);
encoder_class->set_format = GST_DEBUG_FUNCPTR (gst_sbc_enc_set_format);
encoder_class->handle_frame = GST_DEBUG_FUNCPTR (gst_sbc_enc_handle_frame);
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sbc_enc_sink_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sbc_enc_src_factory));
gst_element_class_set_static_metadata (element_class,
"Bluetooth SBC audio encoder", "Codec/Encoder/Audio",
"Encode an SBC audio stream", "Marcel Holtmann <marcel@holtmann.org>");
GST_DEBUG_CATEGORY_INIT (sbc_enc_debug, "sbcenc", 0, "SBC encoding element");
}
static void
gst_sbc_enc_init (GstSbcEnc * self)
{
self->subbands = 0;
self->blocks = 0;
self->rate = 0;
self->channels = 0;
self->bitpool = 0;
}