text: /* Spa A2DP SBC codec
   *
   * Copyright © 2020 Wim Taymans
   *
   * Permission is hereby granted, free of charge, to any person obtaining a
   * copy of this software and associated documentation files (the "Software"),
   * to deal in the Software without restriction, including without limitation
   * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   * and/or sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice (including the next
   * paragraph) shall be included in all copies or substantial portions of the
   * Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
   * DEALINGS IN THE SOFTWARE.
   */
  
  #include <unistd.h>
  #include <stddef.h>
  #include <errno.h>
  #include <arpa/inet.h>
  
  #include <spa/param/audio/format.h>
  
  #include <sbc/sbc.h>
  
  #include "defs.h"
  #include "rtp.h"
  #include "a2dp-codecs.h"
  
  #define MAX_FRAME_COUNT 16
  
  struct impl {
  	sbc_t sbc;
  
  	struct rtp_header *header;
  	struct rtp_payload *payload;
  
  	size_t mtu;
  	int codesize;
  	int max_frames;
  
  	int min_bitpool;
  	int max_bitpool;
  };
  
  static int codec_fill_caps(const struct a2dp_codec *codec, uint32_t flags,
  		uint8_t caps[A2DP_MAX_CAPS_SIZE])
  {
  	const a2dp_sbc_t a2dp_sbc = {
  		.frequency =
  			SBC_SAMPLING_FREQ_16000 |
  			SBC_SAMPLING_FREQ_32000 |
  			SBC_SAMPLING_FREQ_44100 |
  			SBC_SAMPLING_FREQ_48000,
  		.channel_mode =
  			SBC_CHANNEL_MODE_MONO |
  			SBC_CHANNEL_MODE_DUAL_CHANNEL |
  			SBC_CHANNEL_MODE_STEREO |
  			SBC_CHANNEL_MODE_JOINT_STEREO,
  		.block_length =
  			SBC_BLOCK_LENGTH_4 |
  			SBC_BLOCK_LENGTH_8 |
  			SBC_BLOCK_LENGTH_12 |
  			SBC_BLOCK_LENGTH_16,
  		.subbands =
  			SBC_SUBBANDS_4 |
  			SBC_SUBBANDS_8,
  		.allocation_method =
  			SBC_ALLOCATION_SNR |
  			SBC_ALLOCATION_LOUDNESS,
  		.min_bitpool = SBC_MIN_BITPOOL,
  		.max_bitpool = SBC_MAX_BITPOOL,
  	};
  	memcpy(caps, &a2dp_sbc, sizeof(a2dp_sbc));
  	return sizeof(a2dp_sbc);
  }
  
  static uint8_t default_bitpool(uint8_t freq, uint8_t mode, bool xq)
  {
  	/* A2DP spec v1.2 states that all SNK implementation shall handle bitrates
  	 * of up to 512 kbps (~ bitpool = 86 stereo, or 2x43 dual channel at 44.1KHz
  	 * or ~ bitpool = 78 stereo, or 2x39 dual channel at 48KHz). */
  	switch (freq) {
  	case SBC_SAMPLING_FREQ_16000:
          case SBC_SAMPLING_FREQ_32000:
  		return 64;
  
  	case SBC_SAMPLING_FREQ_44100:
  		switch (mode) {
  		case SBC_CHANNEL_MODE_MONO:
  		case SBC_CHANNEL_MODE_DUAL_CHANNEL:
  			return xq ? 43 : 32;
  
  		case SBC_CHANNEL_MODE_STEREO:
  		case SBC_CHANNEL_MODE_JOINT_STEREO:
  			return xq ? 86 : 64;
  		}
  		return xq ? 86 : 64;
  	case SBC_SAMPLING_FREQ_48000:
  		switch (mode) {
  		case SBC_CHANNEL_MODE_MONO:
  		case SBC_CHANNEL_MODE_DUAL_CHANNEL:
  			return xq ? 39 : 29;
  
  		case SBC_CHANNEL_MODE_STEREO:
  		case SBC_CHANNEL_MODE_JOINT_STEREO:
  			return xq ? 78 : 58;
  		}
  		return xq ? 78 : 58;
  	}
  	return xq ? 86 : 64;
  }
  
  static int codec_select_config(const struct a2dp_codec *codec, uint32_t flags,
  		const void *caps, size_t caps_size,
  		const struct spa_dict *settings, uint8_t config[A2DP_MAX_CAPS_SIZE])
  {
  	a2dp_sbc_t conf;
  	int bitpool;
  	bool xq = false;
  
  	if (caps_size < sizeof(conf))
  		return -EINVAL;
  
  	xq = (strcmp(codec->name, "sbc_xq") == 0);
  
  	memcpy(&conf, caps, sizeof(conf));
  
  	if (xq) {
  		if (conf.frequency & SBC_SAMPLING_FREQ_44100)
  			conf.frequency = SBC_SAMPLING_FREQ_44100;
  		else if (conf.frequency & SBC_SAMPLING_FREQ_48000)
  			conf.frequency = SBC_SAMPLING_FREQ_48000;
  		else
  			return -ENOTSUP;
  	}
  	else if (conf.frequency & SBC_SAMPLING_FREQ_48000)
  		conf.frequency = SBC_SAMPLING_FREQ_48000;
  	else if (conf.frequency & SBC_SAMPLING_FREQ_44100)
  		conf.frequency = SBC_SAMPLING_FREQ_44100;
  	else if (conf.frequency & SBC_SAMPLING_FREQ_32000)
  		conf.frequency = SBC_SAMPLING_FREQ_32000;
  	else if (conf.frequency & SBC_SAMPLING_FREQ_16000)
  		conf.frequency = SBC_SAMPLING_FREQ_16000;
  	else
  		return -ENOTSUP;
  
  	if (xq) {
  		if (conf.channel_mode & SBC_CHANNEL_MODE_DUAL_CHANNEL)
  			conf.channel_mode = SBC_CHANNEL_MODE_DUAL_CHANNEL;
  		else if (conf.channel_mode & SBC_CHANNEL_MODE_JOINT_STEREO)
  			conf.channel_mode = SBC_CHANNEL_MODE_JOINT_STEREO;
  		else if (conf.channel_mode & SBC_CHANNEL_MODE_STEREO)
  			conf.channel_mode = SBC_CHANNEL_MODE_STEREO;
  		else
  			return -ENOTSUP;
  	}
  	else if (conf.channel_mode & SBC_CHANNEL_MODE_JOINT_STEREO)
  		conf.channel_mode = SBC_CHANNEL_MODE_JOINT_STEREO;
  	else if (conf.channel_mode & SBC_CHANNEL_MODE_STEREO)
  		conf.channel_mode = SBC_CHANNEL_MODE_STEREO;
  	else if (conf.channel_mode & SBC_CHANNEL_MODE_DUAL_CHANNEL)
  		conf.channel_mode = SBC_CHANNEL_MODE_DUAL_CHANNEL;
  	else if (conf.channel_mode & SBC_CHANNEL_MODE_MONO)
  		conf.channel_mode = SBC_CHANNEL_MODE_MONO;
  	else
  		return -ENOTSUP;
  
  	if (conf.block_length & SBC_BLOCK_LENGTH_16)
  		conf.block_length = SBC_BLOCK_LENGTH_16;
  	else if (conf.block_length & SBC_BLOCK_LENGTH_12)
  		conf.block_length = SBC_BLOCK_LENGTH_12;
  	else if (conf.block_length & SBC_BLOCK_LENGTH_8)
  		conf.block_length = SBC_BLOCK_LENGTH_8;
  	else if (conf.block_length & SBC_BLOCK_LENGTH_4)
  		conf.block_length = SBC_BLOCK_LENGTH_4;
  	else
  		return -ENOTSUP;
  
  	if (conf.subbands & SBC_SUBBANDS_8)
  		conf.subbands = SBC_SUBBANDS_8;
  	else if (conf.subbands & SBC_SUBBANDS_4)
  		conf.subbands = SBC_SUBBANDS_4;
  	else
  		return -ENOTSUP;
  
  	if (conf.allocation_method & SBC_ALLOCATION_LOUDNESS)
  		conf.allocation_method = SBC_ALLOCATION_LOUDNESS;
  	else if (conf.allocation_method & SBC_ALLOCATION_SNR)
  		conf.allocation_method = SBC_ALLOCATION_SNR;
  	else
  		return -ENOTSUP;
  
  	bitpool = default_bitpool(conf.frequency, conf.channel_mode, xq);
  
  	conf.min_bitpool = SPA_MAX(SBC_MIN_BITPOOL, conf.min_bitpool);
  	conf.max_bitpool = SPA_MIN(bitpool, conf.max_bitpool);
  	memcpy(config, &conf, sizeof(conf));
  
  	return sizeof(conf);
  }
  
  static int codec_caps_preference_cmp(const struct a2dp_codec *codec, const void *caps1, size_t caps1_size,
  		const void *caps2, size_t caps2_size)
  {
  	a2dp_sbc_t conf1, conf2;
  	a2dp_sbc_t *conf;
  	int res1, res2;
  	int a, b;
  	bool xq = (strcmp(codec->name, "sbc_xq") == 0);
  
  	/* Order selected configurations by preference */
  	res1 = codec->select_config(codec, 0, caps1, caps1_size, NULL, (uint8_t *)&conf1);
  	res2 = codec->select_config(codec, 0, caps2, caps2_size, NULL, (uint8_t *)&conf2);
  
  #define PREFER_EXPR(expr)			\
  		do {				\
  			conf = &conf1; 		\
  			a = (expr);		\
  			conf = &conf2;		\
  			b = (expr);		\
  			if (a != b)		\
  				return b - a;	\
  		} while (0)
  
  #define PREFER_BOOL(expr)	PREFER_EXPR((expr) ? 1 : 0)
  
  	/* Prefer valid */
  	a = (res1 > 0 && (size_t)res1 == sizeof(a2dp_sbc_t)) ? 1 : 0;
  	b = (res2 > 0 && (size_t)res2 == sizeof(a2dp_sbc_t)) ? 1 : 0;
  	if (!a || !b)
  		return b - a;
  
  	PREFER_BOOL(conf->frequency & (SBC_SAMPLING_FREQ_48000 | SBC_SAMPLING_FREQ_44100));
  
  	if (xq)
  		PREFER_BOOL(conf->channel_mode & SBC_CHANNEL_MODE_DUAL_CHANNEL);
  	else
  		PREFER_BOOL(conf->channel_mode & SBC_CHANNEL_MODE_JOINT_STEREO);
  
  	PREFER_EXPR(conf->max_bitpool);
  
  	return 0;
  
  #undef PREFER_EXPR
  #undef PREFER_BOOL
  }
  
  static int codec_validate_config(const struct a2dp_codec *codec, uint32_t flags,
  			const void *caps, size_t caps_size,
  			struct spa_audio_info *info)
  {
  	const a2dp_sbc_t *conf;
  
  	if (caps == NULL || caps_size < sizeof(*conf))
  		return -EINVAL;
  
  	conf = caps;
  
  	spa_zero(*info);
  	info->media_type = SPA_MEDIA_TYPE_audio;
  	info->media_subtype = SPA_MEDIA_SUBTYPE_raw;
  	info->info.raw.format = SPA_AUDIO_FORMAT_S16;
  
  	switch (conf->frequency) {
  	case SBC_SAMPLING_FREQ_16000:
  		info->info.raw.rate = 16000;
  		break;
  	case SBC_SAMPLING_FREQ_32000:
  		info->info.raw.rate = 32000;
  		break;
  	case SBC_SAMPLING_FREQ_44100:
  		info->info.raw.rate = 44100;
  		break;
  	case SBC_SAMPLING_FREQ_48000:
  		info->info.raw.rate = 48000;
  		break;
  	default:
  		return -EINVAL;
          }
  
  	switch (conf->channel_mode) {
  	case SBC_CHANNEL_MODE_MONO:
  		info->info.raw.channels = 1;
  		info->info.raw.position[0] = SPA_AUDIO_CHANNEL_MONO;
                  break;
  	case SBC_CHANNEL_MODE_DUAL_CHANNEL:
  	case SBC_CHANNEL_MODE_STEREO:
  	case SBC_CHANNEL_MODE_JOINT_STEREO:
  		info->info.raw.channels = 2;
  		info->info.raw.position[0] = SPA_AUDIO_CHANNEL_FL;
  		info->info.raw.position[1] = SPA_AUDIO_CHANNEL_FR;
                  break;
  	default:
  		return -EINVAL;
          }
  
  	switch (conf->subbands) {
  	case SBC_SUBBANDS_4:
  	case SBC_SUBBANDS_8:
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	switch (conf->block_length) {
  	case SBC_BLOCK_LENGTH_4:
  	case SBC_BLOCK_LENGTH_8:
  	case SBC_BLOCK_LENGTH_12:
  	case SBC_BLOCK_LENGTH_16:
  		break;
  	default:
  		return -EINVAL;
  	}
  	return 0;
  }
  
  static int codec_set_bitpool(struct impl *this, int bitpool)
  {
  	size_t rtp_size = sizeof(struct rtp_header) + sizeof(struct rtp_payload);
  
  	this->sbc.bitpool = SPA_CLAMP(bitpool, this->min_bitpool, this->max_bitpool);
  	this->codesize = sbc_get_codesize(&this->sbc);
  	this->max_frames = (this->mtu - rtp_size) / sbc_get_frame_length(&this->sbc);
  	if (this->max_frames > 15)
  		this->max_frames = 15;
  	return this->sbc.bitpool;
  }
  
  static int codec_enum_config(const struct a2dp_codec *codec,
  		const void *caps, size_t caps_size, uint32_t id, uint32_t idx,
  		struct spa_pod_builder *b, struct spa_pod **param)
  {
  	a2dp_sbc_t conf;
          struct spa_pod_frame f[2];
  	struct spa_pod_choice *choice;
  	uint32_t i = 0;
  	uint32_t position[SPA_AUDIO_MAX_CHANNELS];
  
  	if (caps_size < sizeof(conf))
  		return -EINVAL;
  
  	memcpy(&conf, caps, sizeof(conf));
  
  	if (idx > 0)
  		return 0;
  
  	spa_pod_builder_push_object(b, &f[0], SPA_TYPE_OBJECT_Format, id);
  	spa_pod_builder_add(b,
  			SPA_FORMAT_mediaType,      SPA_POD_Id(SPA_MEDIA_TYPE_audio),
  			SPA_FORMAT_mediaSubtype,   SPA_POD_Id(SPA_MEDIA_SUBTYPE_raw),
  			SPA_FORMAT_AUDIO_format,   SPA_POD_Id(SPA_AUDIO_FORMAT_S16),
  			0);
  	spa_pod_builder_prop(b, SPA_FORMAT_AUDIO_rate, 0);
  
  	spa_pod_builder_push_choice(b, &f[1], SPA_CHOICE_None, 0);
  	choice = (struct spa_pod_choice*)spa_pod_builder_frame(b, &f[1]);
  	i = 0;
  	if (conf.frequency & SBC_SAMPLING_FREQ_48000) {
  		if (i++ == 0)
  			spa_pod_builder_int(b, 48000);
  		spa_pod_builder_int(b, 48000);
  	}
  	if (conf.frequency & SBC_SAMPLING_FREQ_44100) {
  		if (i++ == 0)
  			spa_pod_builder_int(b, 44100);
  		spa_pod_builder_int(b, 44100);
  	}
  	if (conf.frequency & SBC_SAMPLING_FREQ_32000) {
  		if (i++ == 0)
  			spa_pod_builder_int(b, 32000);
  		spa_pod_builder_int(b, 32000);
  	}
  	if (conf.frequency & SBC_SAMPLING_FREQ_16000) {
  		if (i++ == 0)
  			spa_pod_builder_int(b, 16000);
  		spa_pod_builder_int(b, 16000);
  	}
  	if (i > 1)
  		choice->body.type = SPA_CHOICE_Enum;
  	spa_pod_builder_pop(b, &f[1]);
  
  	if (conf.channel_mode & SBC_CHANNEL_MODE_MONO &&
  	    conf.channel_mode & (SBC_CHANNEL_MODE_JOINT_STEREO |
  		    SBC_CHANNEL_MODE_STEREO | SBC_CHANNEL_MODE_DUAL_CHANNEL)) {
  		spa_pod_builder_add(b,
  				SPA_FORMAT_AUDIO_channels, SPA_POD_CHOICE_RANGE_Int(2, 1, 2),
  				0);
  	} else if (conf.channel_mode & SBC_CHANNEL_MODE_MONO) {
  		position[0] = SPA_AUDIO_CHANNEL_MONO;
  		spa_pod_builder_add(b,
  				SPA_FORMAT_AUDIO_channels, SPA_POD_Int(1),
  				SPA_FORMAT_AUDIO_position, SPA_POD_Array(sizeof(uint32_t),
  					SPA_TYPE_Id, 1, position),
  				0);
  	} else {
  		position[0] = SPA_AUDIO_CHANNEL_FL;
  		position[1] = SPA_AUDIO_CHANNEL_FR;
  		spa_pod_builder_add(b,
  				SPA_FORMAT_AUDIO_channels, SPA_POD_Int(2),
  				SPA_FORMAT_AUDIO_position, SPA_POD_Array(sizeof(uint32_t),
  					SPA_TYPE_Id, 2, position),
  				0);
  	}
  	*param = spa_pod_builder_pop(b, &f[0]);
  	return *param == NULL ? -EIO : 1;
  }
  
  static int codec_reduce_bitpool(void *data)
  {
  	struct impl *this = data;
  	return codec_set_bitpool(this, this->sbc.bitpool - 2);
  }
  
  static int codec_increase_bitpool(void *data)
  {
  	struct impl *this = data;
  	return codec_set_bitpool(this, this->sbc.bitpool + 1);
  }
  
  static int codec_get_block_size(void *data)
  {
  	struct impl *this = data;
  	return this->codesize;
  }
  
  static void *codec_init(const struct a2dp_codec *codec, uint32_t flags,
  		void *config, size_t config_len, const struct spa_audio_info *info,
  		void *props, size_t mtu)
  {
  	struct impl *this;
  	a2dp_sbc_t *conf = config;
  	int res;
  
  	this = calloc(1, sizeof(struct impl));
  	if (this == NULL) {
  		res = -errno;
  		goto error;
  	}
  
  	sbc_init(&this->sbc, 0);
  	this->sbc.endian = SBC_LE;
  	this->mtu = mtu;
  
  	if (info->media_type != SPA_MEDIA_TYPE_audio ||
  	    info->media_subtype != SPA_MEDIA_SUBTYPE_raw ||
  	    info->info.raw.format != SPA_AUDIO_FORMAT_S16) {
  		res = -EINVAL;
  		goto error;
  	}
  
  	switch (conf->frequency) {
  	case SBC_SAMPLING_FREQ_16000:
  		this->sbc.frequency = SBC_FREQ_16000;
  		break;
  	case SBC_SAMPLING_FREQ_32000:
  		this->sbc.frequency = SBC_FREQ_32000;
  		break;
  	case SBC_SAMPLING_FREQ_44100:
  		this->sbc.frequency = SBC_FREQ_44100;
  		break;
  	case SBC_SAMPLING_FREQ_48000:
  		this->sbc.frequency = SBC_FREQ_48000;
  		break;
  	default:
  		res = -EINVAL;
                  goto error;
          }
  
  	switch (conf->channel_mode) {
  	case SBC_CHANNEL_MODE_MONO:
  		this->sbc.mode = SBC_MODE_MONO;
                  break;
  	case SBC_CHANNEL_MODE_DUAL_CHANNEL:
  		this->sbc.mode = SBC_MODE_DUAL_CHANNEL;
  		break;
  	case SBC_CHANNEL_MODE_STEREO:
  		this->sbc.mode = SBC_MODE_STEREO;
  		break;
  	case SBC_CHANNEL_MODE_JOINT_STEREO:
  		this->sbc.mode = SBC_MODE_JOINT_STEREO;
                  break;
  	default:
  		res = -EINVAL;
                  goto error;
          }
  
  	switch (conf->subbands) {
  	case SBC_SUBBANDS_4:
  		this->sbc.subbands = SBC_SB_4;
  		break;
  	case SBC_SUBBANDS_8:
  		this->sbc.subbands = SBC_SB_8;
  		break;
  	default:
  		res = -EINVAL;
  		goto error;
  	}
  
  	if (conf->allocation_method & SBC_ALLOCATION_LOUDNESS)
  		this->sbc.allocation = SBC_AM_LOUDNESS;
  	else
  		this->sbc.allocation = SBC_AM_SNR;
  
  	switch (conf->block_length) {
  	case SBC_BLOCK_LENGTH_4:
  		this->sbc.blocks = SBC_BLK_4;
  		break;
  	case SBC_BLOCK_LENGTH_8:
  		this->sbc.blocks = SBC_BLK_8;
  		break;
  	case SBC_BLOCK_LENGTH_12:
  		this->sbc.blocks = SBC_BLK_12;
  		break;
  	case SBC_BLOCK_LENGTH_16:
  		this->sbc.blocks = SBC_BLK_16;
  		break;
  	default:
  		res = -EINVAL;
  		goto error;
  	}
  
  	this->min_bitpool = SPA_MAX(conf->min_bitpool, 12);
  	this->max_bitpool = conf->max_bitpool;
  
  	codec_set_bitpool(this, conf->max_bitpool);
  
  	return this;
  error:
  	errno = -res;
  	return NULL;
  }
  
  static void codec_deinit(void *data)
  {
  	struct impl *this = data;
  	sbc_finish(&this->sbc);
  	free(this);
  }
  
  static int codec_abr_process (void *data, size_t unsent)
  {
  	return -ENOTSUP;
  }
  
  static int codec_start_encode (void *data,
  		void *dst, size_t dst_size, uint16_t seqnum, uint32_t timestamp)
  {
  	struct impl *this = data;
  
  	this->header = (struct rtp_header *)dst;
  	this->payload = SPA_MEMBER(dst, sizeof(struct rtp_header), struct rtp_payload);
  	memset(this->header, 0, sizeof(struct rtp_header)+sizeof(struct rtp_payload));
  
  	this->payload->frame_count = 0;
  	this->header->v = 2;
  	this->header->pt = 1;
  	this->header->sequence_number = htons(seqnum);
  	this->header->timestamp = htonl(timestamp);
  	this->header->ssrc = htonl(1);
  	return sizeof(struct rtp_header) + sizeof(struct rtp_payload);
  }
  
  static int codec_encode(void *data,
  		const void *src, size_t src_size,
  		void *dst, size_t dst_size,
  		size_t *dst_out, int *need_flush)
  {
  	struct impl *this = data;
  	int res;
  
  	res = sbc_encode(&this->sbc, src, src_size,
  			dst, dst_size, (ssize_t*)dst_out);
  	if (SPA_UNLIKELY(res < 0))
  		return -EINVAL;
  	spa_assert(res == this->codesize);
  
  	this->payload->frame_count += res / this->codesize;
  	*need_flush = this->payload->frame_count >= this->max_frames;
  	return res;
  }
  
  static int codec_start_decode (void *data,
  		const void *src, size_t src_size, uint16_t *seqnum, uint32_t *timestamp)
  {
  	const struct rtp_header *header = src;
  	size_t header_size = sizeof(struct rtp_header) + sizeof(struct rtp_payload);
  
  	spa_return_val_if_fail (src_size > header_size, -EINVAL);
  
  	if (seqnum)
  		*seqnum = ntohs(header->sequence_number);
  	if (timestamp)
  		*timestamp = ntohl(header->timestamp);
  	return header_size;
  }
  
  static int codec_decode(void *data,
  		const void *src, size_t src_size,
  		void *dst, size_t dst_size,
  		size_t *dst_out)
  {
  	struct impl *this = data;
  	int res;
  
  	res = sbc_decode(&this->sbc, src, src_size,
  			dst, dst_size, dst_out);
  
  	return res;
  }
  
  const struct a2dp_codec a2dp_codec_sbc = {
  	.id = SPA_BLUETOOTH_AUDIO_CODEC_SBC,
  	.codec_id = A2DP_CODEC_SBC,
  	.name = "sbc",
  	.description = "SBC",
  	.fill_caps = codec_fill_caps,
  	.select_config = codec_select_config,
  	.enum_config = codec_enum_config,
  	.validate_config = codec_validate_config,
  	.caps_preference_cmp = codec_caps_preference_cmp,
  	.init = codec_init,
  	.deinit = codec_deinit,
  	.get_block_size = codec_get_block_size,
  	.abr_process = codec_abr_process,
  	.start_encode = codec_start_encode,
  	.encode = codec_encode,
  	.start_decode = codec_start_decode,
  	.decode = codec_decode,
  	.reduce_bitpool = codec_reduce_bitpool,
  	.increase_bitpool = codec_increase_bitpool,
  };
  
  const struct a2dp_codec a2dp_codec_sbc_xq = {
  	.id = SPA_BLUETOOTH_AUDIO_CODEC_SBC_XQ,
  	.codec_id = A2DP_CODEC_SBC,
  	.name = "sbc_xq",
  	.description = "SBC-XQ",
  	.fill_caps = codec_fill_caps,
  	.select_config = codec_select_config,
  	.enum_config = codec_enum_config,
  	.validate_config = codec_validate_config,
  	.caps_preference_cmp = codec_caps_preference_cmp,
  	.init = codec_init,
  	.deinit = codec_deinit,
  	.get_block_size = codec_get_block_size,
  	.abr_process = codec_abr_process,
  	.start_encode = codec_start_encode,
  	.encode = codec_encode,
  	.start_decode = codec_start_decode,
  	.decode = codec_decode,
  	.reduce_bitpool = codec_reduce_bitpool,
  	.increase_bitpool = codec_increase_bitpool,
  	.feature_flag = "sbc-xq",
  };
  