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/*
* This file is part of MPlayer.
*
* MPlayer is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* MPlayer is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with MPlayer; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MP_AO_INTERNAL_H_
#define MP_AO_INTERNAL_H_
#include <stdbool.h>
#include "audio/chmap.h"
#include "audio/chmap_sel.h"
/* global data used by ao.c and ao drivers */
struct ao {
int samplerate;
struct mp_chmap channels;
int format; // one of AF_FORMAT_...
int bps; // bytes per second (per plane)
int sstride; // size of a sample on each plane
// (format_size*num_channels/num_planes)
int num_planes;
bool probing; // if true, don't fail loudly on init
bool untimed; // don't assume realtime playback
bool no_persistent_volume; // the AO does the equivalent of af_volume
bool per_application_mixer; // like above, but volume persists (per app)
int device_buffer; // device buffer in samples (guessed by
// common init code if not set by driver)
const struct ao_driver *api; // entrypoints to the wrapper (push.c/pull.c)
const struct ao_driver *driver;
void *priv;
struct encode_lavc_context *encode_lavc_ctx;
struct input_ctx *input_ctx;
struct mp_log *log; // Using e.g. "[ao/coreaudio]" as prefix
int buffer;
void *api_priv;
};
extern const struct ao_driver ao_api_push;
extern const struct ao_driver ao_api_pull;
/* Note:
*
* In general, there are two types of audio drivers:
* a) push based (the user queues data that should be played)
* b) pull callback based (the audio API calls a callback to get audio)
*
* The ao.c code can handle both. It basically implements two audio paths
* and provides a uniform API for them. If ao_driver->play is NULL, it assumes
* that the driver uses a callback based audio API, otherwise push based.
*
* Requirements:
* a) Most functions (except ->control) must be provided. ->play is called to
* queue audio. ao.c creates a thread to regularly refill audio device
* buffers with ->play, but all driver functions are always called under
* an exclusive lock.
* Mandatory:
* init
* uninit
* reset
* get_space
* play
* get_delay
* pause
* resume
* b) ->play must be NULL. The driver can start the audio API in init(). The
* audio API in turn will start a thread and call a callback provided by the
* driver. That callback calls ao_read_data() to get audio data. Most
* functions are optional and will be emulated if missing (e.g. pausing
* is emulated as silence). ->get_delay and ->get_space are never called.
* Mandatory:
* init
* uninit
*/
struct ao_driver {
// If true, use with encoding only.
bool encode;
// Name used for --ao.
const char *name;
// Description shown with --ao=help.
const char *description;
// Init the device using ao->format/ao->channels/ao->samplerate. If the
// device doesn't accept these parameters, you can attempt to negotiate
// fallback parameters, and set the ao format fields accordingly.
int (*init)(struct ao *ao);
// Optional. See ao_control() etc. in ao.c
int (*control)(struct ao *ao, enum aocontrol cmd, void *arg);
void (*uninit)(struct ao *ao);
void (*reset)(struct ao*ao);
int (*get_space)(struct ao *ao);
int (*play)(struct ao *ao, void **data, int samples, int flags);
float (*get_delay)(struct ao *ao);
void (*pause)(struct ao *ao);
void (*resume)(struct ao *ao);
void (*drain)(struct ao *ao);
// For option parsing (see vo.h)
int priv_size;
const void *priv_defaults;
const struct m_option *options;
};
// These functions can be called by AOs.
int ao_play_silence(struct ao *ao, int samples);
void ao_wait_drain(struct ao *ao);
int ao_read_data(struct ao *ao, void **data, int samples, int64_t out_time_us);
bool ao_chmap_sel_adjust(struct ao *ao, const struct mp_chmap_sel *s,
struct mp_chmap *map);
bool ao_chmap_sel_get_def(struct ao *ao, const struct mp_chmap_sel *s,
struct mp_chmap *map, int num);
#endif
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