SDL  2.0
testresample.c
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1 /*
2  Copyright (C) 1997-2018 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 
13 #include "SDL.h"
14 
15 int
16 main(int argc, char **argv)
17 {
18  SDL_AudioSpec spec;
19  SDL_AudioCVT cvt;
20  Uint32 len = 0;
21  Uint8 *data = NULL;
22  int cvtfreq = 0;
23  int cvtchans = 0;
24  int bitsize = 0;
25  int blockalign = 0;
26  int avgbytes = 0;
27  SDL_RWops *io = NULL;
28 
29  /* Enable standard application logging */
30  SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
31 
32  if (argc != 5) {
33  SDL_Log("USAGE: %s in.wav out.wav newfreq newchans\n", argv[0]);
34  return 1;
35  }
36 
37  cvtfreq = SDL_atoi(argv[3]);
38  cvtchans = SDL_atoi(argv[4]);
39 
40  if (SDL_Init(SDL_INIT_AUDIO) == -1) {
41  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "SDL_Init() failed: %s\n", SDL_GetError());
42  return 2;
43  }
44 
45  if (SDL_LoadWAV(argv[1], &spec, &data, &len) == NULL) {
46  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "failed to load %s: %s\n", argv[1], SDL_GetError());
47  SDL_Quit();
48  return 3;
49  }
50 
51  if (SDL_BuildAudioCVT(&cvt, spec.format, spec.channels, spec.freq,
52  spec.format, cvtchans, cvtfreq) == -1) {
53  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "failed to build CVT: %s\n", SDL_GetError());
54  SDL_FreeWAV(data);
55  SDL_Quit();
56  return 4;
57  }
58 
59  cvt.len = len;
60  cvt.buf = (Uint8 *) SDL_malloc(len * cvt.len_mult);
61  if (cvt.buf == NULL) {
62  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Out of memory.\n");
63  SDL_FreeWAV(data);
64  SDL_Quit();
65  return 5;
66  }
67  SDL_memcpy(cvt.buf, data, len);
68 
69  if (SDL_ConvertAudio(&cvt) == -1) {
70  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Conversion failed: %s\n", SDL_GetError());
71  SDL_free(cvt.buf);
72  SDL_FreeWAV(data);
73  SDL_Quit();
74  return 6;
75  }
76 
77  /* write out a WAV header... */
78  io = SDL_RWFromFile(argv[2], "wb");
79  if (io == NULL) {
80  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "fopen('%s') failed: %s\n", argv[2], SDL_GetError());
81  SDL_free(cvt.buf);
82  SDL_FreeWAV(data);
83  SDL_Quit();
84  return 7;
85  }
86 
87  bitsize = SDL_AUDIO_BITSIZE(spec.format);
88  blockalign = (bitsize / 8) * cvtchans;
89  avgbytes = cvtfreq * blockalign;
90 
91  SDL_WriteLE32(io, 0x46464952); /* RIFF */
92  SDL_WriteLE32(io, cvt.len_cvt + 36);
93  SDL_WriteLE32(io, 0x45564157); /* WAVE */
94  SDL_WriteLE32(io, 0x20746D66); /* fmt */
95  SDL_WriteLE32(io, 16); /* chunk size */
96  SDL_WriteLE16(io, SDL_AUDIO_ISFLOAT(spec.format) ? 3 : 1); /* uncompressed */
97  SDL_WriteLE16(io, cvtchans); /* channels */
98  SDL_WriteLE32(io, cvtfreq); /* sample rate */
99  SDL_WriteLE32(io, avgbytes); /* average bytes per second */
100  SDL_WriteLE16(io, blockalign); /* block align */
101  SDL_WriteLE16(io, bitsize); /* significant bits per sample */
102  SDL_WriteLE32(io, 0x61746164); /* data */
103  SDL_WriteLE32(io, cvt.len_cvt); /* size */
104  SDL_RWwrite(io, cvt.buf, cvt.len_cvt, 1);
105 
106  if (SDL_RWclose(io) == -1) {
107  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "fclose('%s') failed: %s\n", argv[2], SDL_GetError());
108  SDL_free(cvt.buf);
109  SDL_FreeWAV(data);
110  SDL_Quit();
111  return 8;
112  } /* if */
113 
114  SDL_free(cvt.buf);
115  SDL_FreeWAV(data);
116  SDL_Quit();
117  return 0;
118 } /* main */
119 
120 /* end of testresample.c ... */