bt/stack/include/a2dp_sbc.h

/******************************************************************************
 *
 *  Copyright (C) 2000-2012 Broadcom Corporation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at:
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  Interface to low complexity subband codec (SBC)
 *
 ******************************************************************************/
#ifndef A2DP_SBC_H
#define A2DP_SBC_H

#include "a2dp_api.h"
#include "avdt_api.h"

#ifdef __cplusplus
extern "C" {
#endif

/*****************************************************************************
**  Constants
*****************************************************************************/
/* the length of the SBC Media Payload header. */
#define A2DP_SBC_MPL_HDR_LEN 1

/* the LOSC of SBC media codec capabilitiy */
#define A2DP_SBC_INFO_LEN 6

/* for Codec Specific Information Element */
#define A2DP_SBC_IE_SAMP_FREQ_MSK 0xF0 /* b7-b4 sampling frequency */
#define A2DP_SBC_IE_SAMP_FREQ_16 0x80  /* b7:16  kHz */
#define A2DP_SBC_IE_SAMP_FREQ_32 0x40  /* b6:32  kHz */
#define A2DP_SBC_IE_SAMP_FREQ_44 0x20  /* b5:44.1kHz */
#define A2DP_SBC_IE_SAMP_FREQ_48 0x10  /* b4:48  kHz */

#define A2DP_SBC_IE_CH_MD_MSK 0x0F    /* b3-b0 channel mode */
#define A2DP_SBC_IE_CH_MD_MONO 0x08   /* b3: mono */
#define A2DP_SBC_IE_CH_MD_DUAL 0x04   /* b2: dual */
#define A2DP_SBC_IE_CH_MD_STEREO 0x02 /* b1: stereo */
#define A2DP_SBC_IE_CH_MD_JOINT 0x01  /* b0: joint stereo */

#define A2DP_SBC_IE_BLOCKS_MSK 0xF0 /* b7-b4 number of blocks */
#define A2DP_SBC_IE_BLOCKS_4 0x80   /* 4 blocks */
#define A2DP_SBC_IE_BLOCKS_8 0x40   /* 8 blocks */
#define A2DP_SBC_IE_BLOCKS_12 0x20  /* 12blocks */
#define A2DP_SBC_IE_BLOCKS_16 0x10  /* 16blocks */

#define A2DP_SBC_IE_SUBBAND_MSK 0x0C /* b3-b2 number of subbands */
#define A2DP_SBC_IE_SUBBAND_4 0x08   /* b3: 4 */
#define A2DP_SBC_IE_SUBBAND_8 0x04   /* b2: 8 */

#define A2DP_SBC_IE_ALLOC_MD_MSK 0x03 /* b1-b0 allocation mode */
#define A2DP_SBC_IE_ALLOC_MD_S 0x02   /* b1: SNR */
#define A2DP_SBC_IE_ALLOC_MD_L 0x01   /* b0: loundess */

#define A2DP_SBC_IE_MIN_BITPOOL 2
#define A2DP_SBC_IE_MAX_BITPOOL 250

/* for media payload header */
#define A2DP_SBC_HDR_F_MSK 0x80
#define A2DP_SBC_HDR_S_MSK 0x40
#define A2DP_SBC_HDR_L_MSK 0x20
#define A2DP_SBC_HDR_NUM_MSK 0x0F

/*****************************************************************************
**  Type Definitions
*****************************************************************************/

/*****************************************************************************
**  External Function Declarations
*****************************************************************************/

// Gets the A2DP SBC Source codec name.
const char* A2DP_CodecSepIndexStrSbc(void);

// Gets the A2DP SBC Sink codec name.
const char* A2DP_CodecSepIndexStrSbcSink(void);

// Initializes A2DP SBC Source codec information into |tAVDT_CFG| configuration
// entry pointed by |p_cfg|.
bool A2DP_InitCodecConfigSbc(tAVDT_CFG* p_cfg);

// Initializes A2DP SBC Sink codec information into |tAVDT_CFG| configuration
// entry pointed by |p_cfg|.
bool A2DP_InitCodecConfigSbcSink(tAVDT_CFG* p_cfg);

// Checks whether the codec capabilities contain a valid A2DP SBC Source codec.
// NOTE: only codecs that are implemented are considered valid.
// Returns true if |p_codec_info| contains information about a valid SBC codec,
// otherwise false.
bool A2DP_IsSourceCodecValidSbc(const uint8_t* p_codec_info);

// Checks whether the codec capabilities contain a valid A2DP SBC Sink codec.
// NOTE: only codecs that are implemented are considered valid.
// Returns true if |p_codec_info| contains information about a valid SBC codec,
// otherwise false.
bool A2DP_IsSinkCodecValidSbc(const uint8_t* p_codec_info);

// Checks whether the codec capabilities contain a valid peer A2DP SBC Source
// codec.
// NOTE: only codecs that are implemented are considered valid.
// Returns true if |p_codec_info| contains information about a valid SBC codec,
// otherwise false.
bool A2DP_IsPeerSourceCodecValidSbc(const uint8_t* p_codec_info);

// Checks whether the codec capabilities contain a valid peer A2DP SBC Sink
// codec.
// NOTE: only codecs that are implemented are considered valid.
// Returns true if |p_codec_info| contains information about a valid SBC codec,
// otherwise false.
bool A2DP_IsPeerSinkCodecValidSbc(const uint8_t* p_codec_info);

// Checks whether A2DP SBC Source codec is supported.
// |p_codec_info| contains information about the codec capabilities.
// Returns true if the A2DP SBC Source codec is supported, otherwise false.
bool A2DP_IsSourceCodecSupportedSbc(const uint8_t* p_codec_info);

// Checks whether A2DP SBC Sink codec is supported.
// |p_codec_info| contains information about the codec capabilities.
// Returns true if the A2DP SBC Sink codec is supported, otherwise false.
bool A2DP_IsSinkCodecSupportedSbc(const uint8_t* p_codec_info);

// Checks whether an A2DP SBC Source codec for a peer Source device is
// supported.
// |p_codec_info| contains information about the codec capabilities of the
// peer device.
// Returns true if the A2DP SBC Source codec for a peer Source device is
// supported, otherwise false.
bool A2DP_IsPeerSourceCodecSupportedSbc(const uint8_t* p_codec_info);

// Initialize state with the default A2DP SBC codec.
// The initialized state with the codec capabilities is stored in
// |p_codec_info|.
void A2DP_InitDefaultCodecSbc(uint8_t* p_codec_info);

// Sets A2DB SBC Source codec state based on the feeding information from
// |p_feeding_params|.
// The state with the codec capabilities is stored in |p_codec_info|.
// Returns true on success, otherwise false.
bool A2DP_SetSourceCodecSbc(const tA2DP_FEEDING_PARAMS* p_feeding_params,
                            uint8_t* p_codec_info);

// Builds A2DP preferred SBC Sink capability from SBC Source capability.
// |p_src_cap| is the Source capability to use.
// |p_pref_cfg| is the result Sink capability to store.
// Returns |A2DP_SUCCESS| on success, otherwise the corresponding A2DP error
// status code.
tA2DP_STATUS A2DP_BuildSrc2SinkConfigSbc(const uint8_t* p_src_cap,
                                         uint8_t* p_pref_cfg);

// Builds A2DP SBC Sink codec config from SBC Source codec config and SBC Sink
// codec capability.
// |p_src_config| is the A2DP SBC Source codec config to use.
// |p_sink_cap| is the A2DP SBC Sink codec capability to use.
// The result is stored in |p_result_sink_config|.
// Returns |A2DP_SUCCESS| on success, otherwise the corresponding A2DP error
// status code.
tA2DP_STATUS A2DP_BuildSinkConfigSbc(const uint8_t* p_src_config,
                                     const uint8_t* p_sink_cap,
                                     uint8_t* p_result_sink_config);

// Gets the A2DP SBC codec name for a given |p_codec_info|.
const char* A2DP_CodecNameSbc(const uint8_t* p_codec_info);

// Checks whether two A2DP SBC codecs |p_codec_info_a| and |p_codec_info_b|
// have the same type.
// Returns true if the two codecs have the same type, otherwise false.
bool A2DP_CodecTypeEqualsSbc(const uint8_t* p_codec_info_a,
                             const uint8_t* p_codec_info_b);

// Checks whether two A2DP SBC codecs |p_codec_info_a| and |p_codec_info_b|
// are exactly the same.
// Returns true if the two codecs are exactly the same, otherwise false.
// If the codec type is not SBC, the return value is false.
bool A2DP_CodecEqualsSbc(const uint8_t* p_codec_info_a,
                         const uint8_t* p_codec_info_b);

// Checks whether two A2DP SBC codecs |p_codec_info_a| and |p_codec_info_b|
// are different, and A2DP requires reconfiguration.
// Returns true if the two codecs are different and A2DP requires
// reconfiguration, otherwise false.
// If the codec type is not SBC, the return value is true.
bool A2DP_CodecRequiresReconfigSbc(const uint8_t* p_codec_info_a,
                                   const uint8_t* p_codec_info_b);

// Checks if an A2DP SBC codec config |p_codec_config| matches an A2DP SBC
// codec capabilities |p_codec_caps|.
// Returns true if the codec config is supported, otherwise false.
bool A2DP_CodecConfigMatchesCapabilitiesSbc(const uint8_t* p_codec_config,
                                            const uint8_t* p_codec_caps);

// Gets the track sampling frequency value for the A2DP SBC codec.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the track sampling frequency on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetTrackFrequencySbc(const uint8_t* p_codec_info);

// Gets the channel count for the A2DP SBC codec.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the channel count on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetTrackChannelCountSbc(const uint8_t* p_codec_info);

// Gets the number of subbands for the A2DP SBC codec.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the number of subbands on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetNumberOfSubbandsSbc(const uint8_t* p_codec_info);

// Gets the number of blocks for the A2DP SBC codec.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the number of blocks on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetNumberOfBlocksSbc(const uint8_t* p_codec_info);

// Gets the allocation method code for the A2DP SBC codec.
// The actual value is codec-specific.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the allocation method code on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetAllocationMethodCodeSbc(const uint8_t* p_codec_info);

// Gets the channel mode code for the A2DP SBC codec.
// The actual value is codec-specific.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the channel mode code on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetChannelModeCodeSbc(const uint8_t* p_codec_info);

// Gets the sampling frequency code for the A2DP SBC codec.
// The actual value is codec-specific.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the sampling frequency code on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetSamplingFrequencyCodeSbc(const uint8_t* p_codec_info);

// Gets the minimum bitpool for the A2DP SBC codec.
// The actual value is codec-specific.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the minimum bitpool on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetMinBitpoolSbc(const uint8_t* p_codec_info);

// Gets the maximum bitpool for the A2DP SBC codec.
// The actual value is codec-specific.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the maximum bitpool on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetMaxBitpoolSbc(const uint8_t* p_codec_info);

// Gets the channel type for the A2DP SBC Sink codec:
// 1 for mono, or 3 for dual/stereo/joint.
// |p_codec_info| is a pointer to the SBC codec_info to decode.
// Returns the channel type on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetSinkTrackChannelTypeSbc(const uint8_t* p_codec_info);

// Computes the number of frames to process in a time window for the A2DP
// SBC sink codec. |time_interval_ms| is the time interval (in milliseconds).
// |p_codec_info| is a pointer to the codec_info to decode.
// Returns the number of frames to process on success, or -1 if |p_codec_info|
// contains invalid codec information.
int A2DP_GetSinkFramesCountToProcessSbc(uint64_t time_interval_ms,
                                        const uint8_t* p_codec_info);

// Gets the A2DP SBC audio data timestamp from an audio packet.
// |p_codec_info| contains the codec information.
// |p_data| contains the audio data.
// The timestamp is stored in |p_timestamp|.
// Returns true on success, otherwise false.
bool A2DP_GetPacketTimestampSbc(const uint8_t* p_codec_info,
                                const uint8_t* p_data, uint32_t* p_timestamp);

// Builds A2DP SBC codec header for audio data.
// |p_codec_info| contains the codec information.
// |p_buf| contains the audio data.
// |frames_per_packet| is the number of frames in this packet.
// Returns true on success, otherwise false.
bool A2DP_BuildCodecHeaderSbc(const uint8_t* p_codec_info, BT_HDR* p_buf,
                              uint16_t frames_per_packet);

// Decodes and displays SBC codec info (for debugging).
// |p_codec_info| is a pointer to the SBC codec_info to decode and display.
void A2DP_DumpCodecInfoSbc(const uint8_t* p_codec_info);

// Gets the A2DP SBC encoder interface that can be used to encode and prepare
// A2DP packets for transmission - see |tA2DP_ENCODER_INTERFACE|.
// |p_codec_info| contains the codec information.
// Returns the A2DP SBC encoder interface if the |p_codec_info| is valid and
// supported, otherwise NULL.
const tA2DP_ENCODER_INTERFACE* A2DP_GetEncoderInterfaceSbc(
    const uint8_t* p_codec_info);

// Adjusts the A2DP SBC codec, based on local support and Bluetooth
// specification.
// |p_codec_info| contains the codec information to adjust.
// Returns true if |p_codec_info| is valid and supported, otherwise false.
bool A2DP_AdjustCodecSbc(uint8_t* p_codec_info);

#ifdef __cplusplus
}
#endif

#endif /* A2DP_SBC_H */