audio.h File Reference

🔊 Audio Capture and Playback Interface for ascii-chat More...

Go to the source code of this file.

Data Structures
struct	audio_context_t
	Audio context for full-duplex capture and playback. More...
struct	audio_device_info_t
	Audio device information structure. More...
struct	audio_batch_info_t
	Parsed audio batch packet header information. More...

Macros
#define	AUDIO_SAMPLE_RATE   48000
	Audio sample rate (48kHz professional quality, Opus-compatible)
#define	AUDIO_FRAMES_PER_BUFFER   480
	Audio frames per buffer (480 = 10ms at 48kHz, matches WebRTC AEC3 frame size)
#define	AUDIO_CHANNELS   1
	Number of audio channels (1 = mono)
#define	AUDIO_BUFFER_SIZE   (AUDIO_FRAMES_PER_BUFFER * AUDIO_CHANNELS)
	Total audio buffer size (frames × channels)
#define	AUDIO_DEVICE_NAME_MAX   256
	Maximum length of audio device name.

Functions
asciichat_error_t	audio_init (audio_context_t *ctx)
	Initialize audio context and PortAudio.
void	audio_destroy (audio_context_t *ctx)
	Destroy audio context and clean up resources.
void	audio_terminate_portaudio_final (void)
	Terminate PortAudio and free all device resources.
void	audio_set_pipeline (audio_context_t *ctx, void *pipeline)
	Set audio pipeline for echo cancellation.
asciichat_error_t	audio_start_duplex (audio_context_t *ctx)
	Start full-duplex audio (simultaneous capture and playback)
asciichat_error_t	audio_stop_duplex (audio_context_t *ctx)
	Stop full-duplex audio.
asciichat_error_t	audio_read_samples (audio_context_t *ctx, float *buffer, int num_samples)
	Read captured audio samples from capture buffer.
asciichat_error_t	audio_write_samples (audio_context_t *ctx, const float *buffer, int num_samples)
	Write audio samples to playback buffer.
asciichat_error_t	audio_set_realtime_priority (void)
	Request real-time priority for current thread.
asciichat_error_t	audio_list_input_devices (audio_device_info_t **out_devices, unsigned int *out_count)
	List available audio input devices (microphones)
asciichat_error_t	audio_list_output_devices (audio_device_info_t **out_devices, unsigned int *out_count)
	List available audio output devices (speakers)
void	audio_free_device_list (audio_device_info_t *devices)
	Free device list allocated by audio_list_input_devices/audio_list_output_devices.
asciichat_error_t	audio_dequantize_samples (const uint8_t *samples_ptr, uint32_t total_samples, float *out_samples)
	Dequantize network audio samples from int32 to float.
audio_ring_buffer_t *	audio_ring_buffer_create (void)
	Create a new audio ring buffer (for playback with jitter buffering)
audio_ring_buffer_t *	audio_ring_buffer_create_for_capture (void)
	Create a new audio ring buffer for capture (without jitter buffering)
void	audio_ring_buffer_destroy (audio_ring_buffer_t *rb)
	Destroy an audio ring buffer.
void	audio_ring_buffer_register_atomics (audio_ring_buffer_t *rb, const char *context_name)
	Register audio ring buffer atomic fields for debug tracking.
void	audio_ring_buffer_unregister_atomics (audio_ring_buffer_t *rb)
	Unregister audio ring buffer atomic fields.
void	audio_ring_buffer_clear (audio_ring_buffer_t *rb)
	Clear all audio samples from ring buffer.
void	audio_ring_buffer_discard_pending (audio_ring_buffer_t *rb)
asciichat_error_t	audio_ring_buffer_write (audio_ring_buffer_t *rb, const float *data, int samples)
	Write audio samples to ring buffer.
size_t	audio_ring_buffer_read (audio_ring_buffer_t *rb, float *data, size_t samples)
	Read audio samples from ring buffer.
size_t	audio_ring_buffer_peek (audio_ring_buffer_t *rb, float *data, size_t samples)
	Peek at available samples without consuming them (for AEC3 render signal)
size_t	audio_ring_buffer_available_read (audio_ring_buffer_t *rb)
	Get number of samples available for reading.
size_t	audio_ring_buffer_available_write (audio_ring_buffer_t *rb)
	Get number of sample slots available for writing.
void	resample_linear (const float *src, size_t src_samples, float *dst, size_t dst_samples, double src_rate, double dst_rate)
	Resample audio using linear interpolation.
asciichat_error_t	audio_parse_batch_header (const void *data, size_t len, audio_batch_info_t *out_batch)
	Parse an audio batch packet header from raw packet data.
asciichat_error_t	audio_validate_batch_params (const audio_batch_info_t *batch)
	Validate audio batch parameters for sanity.
bool	audio_is_supported_sample_rate (uint32_t sample_rate)
	Check if a sample rate is a standard/supported rate.
void	audio_flush_playback_buffers (audio_context_t *ctx)
	Flush all audio buffers to synchronize with seek operations.
bool	audio_should_enable_microphone (audio_capture_source_t source, bool has_media_audio)
	Determine if microphone should be enabled based on audio source setting and media state.

Detailed Description

🔊 Audio Capture and Playback Interface for ascii-chat

Definition in file include/ascii-chat/audio/audio.h.

Macro Definition Documentation

AUDIO_DEVICE_NAME_MAX

#define AUDIO_DEVICE_NAME_MAX   256

Maximum length of audio device name.

Definition at line 390 of file include/ascii-chat/audio/audio.h.

Function Documentation

audio_ring_buffer_discard_pending()

void audio_ring_buffer_discard_pending

(

audio_ring_buffer_t *

rb

)

Definition at line 1087 of file lib/audio/audio.c.

                                                                {
  if (rb) {
    // Capture the current producer position before the caller writes its new
    // samples. The consumer can drop everything through this point while
    // preserving samples appended afterward.
    unsigned int write_idx = atomic_load_u64(&rb->write_index);
    atomic_store_u64(&rb->discard_to_index, write_idx);
    atomic_store_bool(&rb->discard_pending, true);
  }
}

References atomic_load_u64(), atomic_store_bool(), atomic_store_u64(), audio_ring_buffer::discard_pending, audio_ring_buffer::discard_to_index, and audio_ring_buffer::write_index.

Referenced by audio_ring_buffer_write().