Audio Core Changelog

v0.6.0 - 2022-05-27

Added

  • The Audio Core now supports 20, 24 and 32-bit audio samples.

  • New processing stage that allows packing of 20 or 24-bit audio samples from 32-bit words.

  • New sinus generator endpoint that can produce pre-recorded sin waves at a frequency of 1 kHz, 2 kHz and 3 kHz for testing purposes.

  • New audio mixing module used for mixing up to 3 audio streams into a single one.

  • audio_protocol_cfg_t now has a sac_mixer_option_t in order to select if the pipeline is producing an audio stream to be mixed or if the pipeline is doing the mixing.

  • New API call sac_mixer_module_init() used to initialize the audio mixer module (if used).

  • New API call sac_endpoint_link() used to make 2 endpoints share their audio queue (for use with the audio mixing feature).

  • New API call sac_pipeline_add_extra_producer() used to add more than one audio producer in a pipeline (for use with the audio mixing feature).

  • New SAC_ERR_NULL_PTR error that happens when a pointer is NULL while it should have been initialized.

  • New SAC_ERR_MIXER_INIT_FAILURE error that happens when the mixer is not able to initialize properly due to an erroneous configuration.

  • New audio fallback module.

  • New API call sac_fallback_module_init() used to initialize the audio fallback module (if used).

  • New producer_packets_corrupted_count stat.

  • New CRC4 field in audio header used to validate the content of the audio header.

  • New gate function pointer field in the Audio Processing Interface (sac_processing_interface_t).

Changed

  • Prefix of the SPARK Audio Core (SAC) API changed from audio_ to sac_.

  • audio_protocol.c/h has been renamed to audio_cdc_module.c/h and moved to the module folder.

  • audio_protocol_cfg_t has been renamed to sac_pipeline_cfg_t.

  • Audio core now supports payload size up to 65535 bytes in its pipelines.

  • Audio payload is now aligned with 32-bit words.

  • Audio volume processing stage now has the prefix audio_ on all public functions.

  • The audio processing stage process function now returns a uint16_t payload size.

  • The bit depth field of the endpoint config structure now has a typedef enum to list all supported bit depths.

  • The payload size field of the endpoint config structure now has a uint16_t value.

  • sac_pipeline_process() now mixes audio packets when the audio mixing feature is enabled.

v0.5.0 - 2022-03-03

Added

  • Audio buffer load check inside audio_pipeline_consume().

  • A new field in audio_protocol_cfg_t has been added to turn on or off the user data feature. The audio packet trailing byte will not be appended if it is turned off.

Fixed

  • CDC not properly handling multiple consumers.

v0.4.0 - 2022-02-04

Added

  • New API call audio_processing_stage_init() that initializes a processing stage and returns a reference to it.

  • New API call audio_pipeline_setup() used to do the final setup of the pipeline before it is operational.

  • New API call audio_core_get_allocated_bytes() used to know the number of bytes used in the memory pool.

  • New AUDIO_ERR_PIPELINE_CFG_INVALID error that happens when incompatible pipeline configurations are set.

Changed

  • audio_pipeline_init() now dynamically allocated the pipeline and returns a reference to it.

  • audio_endpoint_init() now dynamically allocated the endpoint and returns a reference to it.

  • Producer endpoint audio_payload_size field needs not to account for audio packet size inflation during subsequent audio processing like in the case of upsampling or decompression. The value must always be set to the exact amount of bytes the produced audio packet is.

  • The block_size field of the src_cmsis_cfg_t type of the Sampling Rate Converter processing stage has been replace by a payload_size field and a bit_depth field.

  • A const qualifier has been added to the name field of the audio_processing_t type.

  • The max_process_count field of the audio_protocol_cfg_t has been removed. Processing stages are allocated dynamically using the chunk of RAM allocated by the application.

  • Error pointer parameter has been added to audio_endpoint_init() and removed from audio_pipeline_add_processing().

  • audio_pipeline_stop() no longer de-initializes processing stages.

Removed

  • WPS audio endpoint. Audio applications must supply their own. A working implementation is provided with the SDK.

v0.3.0 - 2021-12-13

Added

  • Support for multiple audio consumers on a single audio pipeline.

  • Constant for ADPCM overhead and producer queue size.

Changed

  • Pipeline configuration variable name from queue_avg_size to cdc_queue_avg_size.

Removed

  • Generic I2S audio endpoint. Audio applications can create their own specific audio endpoints if needed instead.

Fixed

  • Coding style.

v0.2.0 - 2021-11-09

Changed

  • Sampling rate converter processing stage filter coefficients when interpolating.

v0.1.0 - 2021-09-30

Initial release.