1/*
2 Copyright (C) 1997-2021 Sam Lantinga <slouken@libsdl.org>
3
4 This software is provided 'as-is', without any express or implied
5 warranty. In no event will the authors be held liable for any damages
6 arising from the use of this software.
7
8 Permission is granted to anyone to use this software for any purpose,
9 including commercial applications, and to alter it and redistribute it
10 freely.
11*/
12#include "SDL.h"
13
14#include <stdlib.h>
15
16#ifdef __EMSCRIPTEN__
17#include <emscripten/emscripten.h>
18#endif
19
20static SDL_Window *window = NULL;
21static SDL_Renderer *renderer = NULL;
22static SDL_AudioSpec spec;
23static SDL_AudioDeviceID devid_in = 0;
24static SDL_AudioDeviceID devid_out = 0;
25
26static void
27loop()
28{
29 SDL_bool please_quit = SDL_FALSE;
30 SDL_Event e;
31
32 while (SDL_PollEvent(&e)) {
33 if (e.type == SDL_QUIT) {
34 please_quit = SDL_TRUE;
35 } else if (e.type == SDL_KEYDOWN) {
36 if (e.key.keysym.sym == SDLK_ESCAPE) {
37 please_quit = SDL_TRUE;
38 }
39 } else if (e.type == SDL_MOUSEBUTTONDOWN) {
40 if (e.button.button == 1) {
41 SDL_PauseAudioDevice(devid_out, SDL_TRUE);
42 SDL_PauseAudioDevice(devid_in, SDL_FALSE);
43 }
44 } else if (e.type == SDL_MOUSEBUTTONUP) {
45 if (e.button.button == 1) {
46 SDL_PauseAudioDevice(devid_in, SDL_TRUE);
47 SDL_PauseAudioDevice(devid_out, SDL_FALSE);
48 }
49 }
50 }
51
52 if (SDL_GetAudioDeviceStatus(devid_in) == SDL_AUDIO_PLAYING) {
53 SDL_SetRenderDrawColor(renderer, 0, 255, 0, 255);
54 } else {
55 SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);
56 }
57 SDL_RenderClear(renderer);
58 SDL_RenderPresent(renderer);
59
60 if (please_quit) {
61 /* stop playing back, quit. */
62 SDL_Log("Shutting down.\n");
63 SDL_PauseAudioDevice(devid_in, 1);
64 SDL_CloseAudioDevice(devid_in);
65 SDL_PauseAudioDevice(devid_out, 1);
66 SDL_CloseAudioDevice(devid_out);
67 SDL_DestroyRenderer(renderer);
68 SDL_DestroyWindow(window);
69 SDL_Quit();
70 #ifdef __EMSCRIPTEN__
71 emscripten_cancel_main_loop();
72 #endif
73 exit(0);
74 }
75
76 /* Note that it would be easier to just have a one-line function that
77 calls SDL_QueueAudio() as a capture device callback, but we're
78 trying to test the API, so we use SDL_DequeueAudio() here. */
79 while (SDL_TRUE) {
80 Uint8 buf[1024];
81 const Uint32 br = SDL_DequeueAudio(devid_in, buf, sizeof (buf));
82 SDL_QueueAudio(devid_out, buf, br);
83 if (br < sizeof (buf)) {
84 break;
85 }
86 }
87}
88
89int
90main(int argc, char **argv)
91{
92 /* (argv[1] == NULL means "open default device.") */
93 const char *devname = argv[1];
94 SDL_AudioSpec wanted;
95 int devcount;
96 int i;
97
98 /* Enable standard application logging */
99 SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
100
101 /* Load the SDL library */
102 if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO) < 0) {
103 SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
104 return (1);
105 }
106
107 window = SDL_CreateWindow("testaudiocapture", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 320, 240, 0);
108 renderer = SDL_CreateRenderer(window, -1, 0);
109 SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
110 SDL_RenderClear(renderer);
111 SDL_RenderPresent(renderer);
112
113 SDL_Log("Using audio driver: %s\n", SDL_GetCurrentAudioDriver());
114
115 devcount = SDL_GetNumAudioDevices(SDL_TRUE);
116 for (i = 0; i < devcount; i++) {
117 SDL_Log(" Capture device #%d: '%s'\n", i, SDL_GetAudioDeviceName(i, SDL_TRUE));
118 }
119
120 SDL_zero(wanted);
121 wanted.freq = 44100;
122 wanted.format = AUDIO_F32SYS;
123 wanted.channels = 1;
124 wanted.samples = 4096;
125 wanted.callback = NULL;
126
127 SDL_zero(spec);
128
129 /* DirectSound can fail in some instances if you open the same hardware
130 for both capture and output and didn't open the output end first,
131 according to the docs, so if you're doing something like this, always
132 open your capture devices second in case you land in those bizarre
133 circumstances. */
134
135 SDL_Log("Opening default playback device...\n");
136 devid_out = SDL_OpenAudioDevice(NULL, SDL_FALSE, &wanted, &spec, SDL_AUDIO_ALLOW_ANY_CHANGE);
137 if (!devid_out) {
138 SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open an audio device for playback: %s!\n", SDL_GetError());
139 SDL_Quit();
140 exit(1);
141 }
142
143 SDL_Log("Opening capture device %s%s%s...\n",
144 devname ? "'" : "",
145 devname ? devname : "[[default]]",
146 devname ? "'" : "");
147
148 devid_in = SDL_OpenAudioDevice(argv[1], SDL_TRUE, &spec, &spec, 0);
149 if (!devid_in) {
150 SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open an audio device for capture: %s!\n", SDL_GetError());
151 SDL_Quit();
152 exit(1);
153 }
154
155 SDL_Log("Ready! Hold down mouse or finger to record!\n");
156
157#ifdef __EMSCRIPTEN__
158 emscripten_set_main_loop(loop, 0, 1);
159#else
160 while (1) { loop(); SDL_Delay(16); }
161#endif
162
163 return 0;
164}
165
166