PipeWire  0.3.52
audio-src.c

Audio source using pw_stream.

/* PipeWire
*
* Copyright © 2018 Wim Taymans
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
/*
[title]
Audio source using \ref pw_stream "pw_stream".
[title]
*/
#include <stdio.h>
#include <errno.h>
#include <math.h>
#include <signal.h>
#define M_PI_M2 ( M_PI + M_PI )
#define DEFAULT_RATE 44100
#define DEFAULT_CHANNELS 2
#define DEFAULT_VOLUME 0.7
struct data {
struct pw_main_loop *loop;
struct pw_stream *stream;
double accumulator;
};
static void fill_f32(struct data *d, void *dest, int n_frames)
{
float *dst = dest, val;
int i, c;
for (i = 0; i < n_frames; i++) {
d->accumulator += M_PI_M2 * 440 / DEFAULT_RATE;
if (d->accumulator >= M_PI_M2)
d->accumulator -= M_PI_M2;
val = sin(d->accumulator) * DEFAULT_VOLUME;
for (c = 0; c < DEFAULT_CHANNELS; c++)
*dst++ = val;
}
}
/* our data processing function is in general:
*
* struct pw_buffer *b;
* b = pw_stream_dequeue_buffer(stream);
*
* .. generate stuff in the buffer ...
*
* pw_stream_queue_buffer(stream, b);
*/
static void on_process(void *userdata)
{
struct data *data = userdata;
struct pw_buffer *b;
struct spa_buffer *buf;
int n_frames, stride;
uint8_t *p;
if ((b = pw_stream_dequeue_buffer(data->stream)) == NULL) {
pw_log_warn("out of buffers: %m");
return;
}
buf = b->buffer;
if ((p = buf->datas[0].data) == NULL)
return;
stride = sizeof(float) * DEFAULT_CHANNELS;
n_frames = SPA_MIN(b->requested, buf->datas[0].maxsize / stride);
fill_f32(data, p, n_frames);
buf->datas[0].chunk->offset = 0;
buf->datas[0].chunk->stride = stride;
buf->datas[0].chunk->size = n_frames * stride;
pw_stream_queue_buffer(data->stream, b);
}
static const struct pw_stream_events stream_events = {
.process = on_process,
};
static void do_quit(void *userdata, int signal_number)
{
struct data *data = userdata;
pw_main_loop_quit(data->loop);
}
int main(int argc, char *argv[])
{
struct data data = { 0, };
const struct spa_pod *params[1];
uint8_t buffer[1024];
struct spa_pod_builder b = SPA_POD_BUILDER_INIT(buffer, sizeof(buffer));
pw_init(&argc, &argv);
/* make a main loop. If you already have another main loop, you can add
* the fd of this pipewire mainloop to it. */
data.loop = pw_main_loop_new(NULL);
pw_loop_add_signal(pw_main_loop_get_loop(data.loop), SIGTERM, do_quit, &data);
/* Create a simple stream, the simple stream manages the core and remote
* objects for you if you don't need to deal with them.
*
* If you plan to autoconnect your stream, you need to provide at least
* media, category and role properties.
*
* Pass your events and a user_data pointer as the last arguments. This
* will inform you about the stream state. The most important event
* you need to listen to is the process event where you need to produce
* the data.
*/
"audio-src",
PW_KEY_MEDIA_CATEGORY, "Playback",
NULL),
&stream_events,
&data);
/* Make one parameter with the supported formats. The SPA_PARAM_EnumFormat
* id means that this is a format enumeration (of 1 value). */
.channels = DEFAULT_CHANNELS,
.rate = DEFAULT_RATE ));
/* Now connect this stream. We ask that our process function is
* called in a realtime thread. */
argc > 1 ? (uint32_t)atoi(argv[1]) : PW_ID_ANY,
params, 1);
/* and wait while we let things run */
return 0;
}
#define PW_ID_ANY
Definition: core.h:83
#define PW_KEY_MEDIA_TYPE
Media.
Definition: keys.h:429
#define PW_KEY_MEDIA_ROLE
Role: Movie, Music, Camera, Screen, Communication, Game, Notification, DSP, Production,...
Definition: keys.h:435
#define PW_KEY_MEDIA_CATEGORY
Media Category: Playback, Capture, Duplex, Monitor, Manager.
Definition: keys.h:432
#define pw_log_warn(...)
Definition: log.h:163
#define pw_loop_add_signal(l,...)
Definition: loop.h:83
struct pw_main_loop * pw_main_loop_new(const struct spa_dict *props)
Create a new main loop.
Definition: main-loop.c:80
int pw_main_loop_quit(struct pw_main_loop *loop)
Quit a main loop.
Definition: main-loop.c:125
void pw_main_loop_destroy(struct pw_main_loop *loop)
Destroy a loop.
Definition: main-loop.c:90
int pw_main_loop_run(struct pw_main_loop *loop)
Run a main loop.
Definition: main-loop.c:139
struct pw_loop * pw_main_loop_get_loop(struct pw_main_loop *loop)
Get the loop implementation.
Definition: main-loop.c:113
void pw_init(int *argc, char **argv[])
Initialize PipeWire.
Definition: pipewire.c:580
void pw_deinit(void)
Deinitialize PipeWire.
Definition: pipewire.c:683
#define PW_DIRECTION_OUTPUT
Definition: port.h:67
struct pw_properties * pw_properties_new(const char *key,...) 1
Make a new properties object.
Definition: properties.c:102
int pw_stream_connect(struct pw_stream *stream, enum pw_direction direction, uint32_t target_id, enum pw_stream_flags flags, const struct spa_pod **params, uint32_t n_params)
Connect a stream for input or output on port_path.
Definition: stream.c:1773
struct pw_stream * pw_stream_new_simple(struct pw_loop *loop, const char *name, struct pw_properties *props, const struct pw_stream_events *events, void *data)
Definition: stream.c:1520
struct pw_buffer * pw_stream_dequeue_buffer(struct pw_stream *stream)
Get a buffer that can be filled for playback streams or consumed for capture streams.
Definition: stream.c:2226
int pw_stream_queue_buffer(struct pw_stream *stream, struct pw_buffer *buffer)
Submit a buffer for playback or recycle a buffer for capture.
Definition: stream.c:2253
#define PW_VERSION_STREAM_EVENTS
Definition: stream.h:337
void pw_stream_destroy(struct pw_stream *stream)
Destroy a stream.
Definition: stream.c:1582
@ PW_STREAM_FLAG_MAP_BUFFERS
mmap the buffers except DmaBuf
Definition: stream.h:385
@ PW_STREAM_FLAG_AUTOCONNECT
try to automatically connect this stream
Definition: stream.h:380
@ PW_STREAM_FLAG_RT_PROCESS
call process from the realtime thread.
Definition: stream.h:387
static struct spa_pod * spa_format_audio_raw_build(struct spa_pod_builder *builder, uint32_t id, struct spa_audio_info_raw *info)
Definition: format-utils.h:108
#define SPA_AUDIO_INFO_RAW_INIT(...)
Definition: raw.h:307
@ SPA_PARAM_EnumFormat
available formats as SPA_TYPE_OBJECT_Format
Definition: param.h:53
@ SPA_AUDIO_FORMAT_F32
Definition: raw.h:126
#define SPA_POD_BUILDER_INIT(buffer, size)
Definition: builder.h:82
#define SPA_MIN(a, b)
Definition: defs.h:146
pipewire/pipewire.h
a buffer structure obtained from pw_stream_dequeue_buffer().
Definition: stream.h:210
uint64_t requested
For playback streams, this field contains the suggested amount of data to provide.
Definition: stream.h:217
struct spa_buffer * buffer
the spa buffer
Definition: stream.h:211
A main loop object.
Events for a stream.
Definition: stream.h:335
A Buffer.
Definition: buffer.h:109
struct spa_data * datas
array of data members
Definition: buffer.h:113
int32_t stride
stride of valid data
Definition: buffer.h:68
uint32_t size
size of valid data.
Definition: buffer.h:66
uint32_t offset
offset of valid data.
Definition: buffer.h:63
struct spa_chunk * chunk
valid chunk of memory
Definition: buffer.h:105
void * data
optional data pointer
Definition: buffer.h:104
uint32_t maxsize
max size of data
Definition: buffer.h:103
Definition: builder.h:73
void * data
Definition: builder.h:74
Definition: pod.h:63