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/* Simple Plugin API */
/* SPDX-FileCopyrightText: Copyright © 2023 Wim Taymans */
/* SPDX-License-Identifier: MIT */
#ifndef SPA_PARAM_LATENY_H
#define SPA_PARAM_LATENY_H
#ifdef __cplusplus
extern "C" {
#endif
/**
* \addtogroup spa_param
* \{
*/
#include <spa/param/param.h>
/**
* Properties for SPA_TYPE_OBJECT_ParamLatency
*
* The latency indicates:
*
* - for playback: time delay between start of a graph cycle, and the rendering of
* the first sample of that cycle in audio output.
*
* - for capture: time delay between start of a graph cycle, and the first sample
* of that cycle having occurred in audio input.
*
* For physical output/input, the latency is intended to correspond to the
* rendering/capture of physical audio, including hardware internal rendering delay.
*
* The latency values are adjusted by \ref SPA_PROP_latencyOffsetNsec or
* SPA_PARAM_ProcessLatency, if present. (e.g. for ALSA this is used to adjust for
* the internal hardware latency).
*/
enum spa_param_latency {
SPA_PARAM_LATENCY_START,
SPA_PARAM_LATENCY_direction, /**< direction, input/output (Id enum spa_direction) */
SPA_PARAM_LATENCY_minQuantum, /**< min latency relative to quantum (Float) */
SPA_PARAM_LATENCY_maxQuantum, /**< max latency relative to quantum (Float) */
SPA_PARAM_LATENCY_minRate, /**< min latency (Int) relative to graph rate */
SPA_PARAM_LATENCY_maxRate, /**< max latency (Int) relative to graph rate */
SPA_PARAM_LATENCY_minNs, /**< min latency (Long) in nanoseconds */
SPA_PARAM_LATENCY_maxNs, /**< max latency (Long) in nanoseconds */
};
/** helper structure for managing latency objects */
struct spa_latency_info {
enum spa_direction direction;
float min_quantum;
float max_quantum;
int32_t min_rate;
int32_t max_rate;
int64_t min_ns;
int64_t max_ns;
};
#define SPA_LATENCY_INFO(dir,...) ((struct spa_latency_info) { .direction = (dir), ## __VA_ARGS__ })
/**
* Properties for SPA_TYPE_OBJECT_ParamProcessLatency
*
* The processing latency indicates logical time delay between a sample in an input port,
* and a corresponding sample in an output port, relative to the graph time.
*/
enum spa_param_process_latency {
SPA_PARAM_PROCESS_LATENCY_START,
SPA_PARAM_PROCESS_LATENCY_quantum, /**< latency relative to quantum (Float) */
SPA_PARAM_PROCESS_LATENCY_rate, /**< latency (Int) relative to graph rate */
SPA_PARAM_PROCESS_LATENCY_ns, /**< latency (Long) in nanoseconds */
};
/** Helper structure for managing process latency objects */
struct spa_process_latency_info {
float quantum;
int32_t rate;
int64_t ns;
};
#define SPA_PROCESS_LATENCY_INFO_INIT(...) ((struct spa_process_latency_info) { __VA_ARGS__ })
/**
* \}
*/
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* SPA_PARAM_LATENY_H */