1 /* Copyright (c) 2013 Jean-Marc Valin */
2 /*
3 Redistribution and use in source and binary forms, with or without
4 modification, are permitted provided that the following conditions
5 are met:
6
7 - Redistributions of source code must retain the above copyright
8 notice, this list of conditions and the following disclaimer.
9
10 - Redistributions in binary form must reproduce the above copyright
11 notice, this list of conditions and the following disclaimer in the
12 documentation and/or other materials provided with the distribution.
13
14 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
15 ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
16 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
17 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
18 OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
22 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
23 NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
24 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 /* This is meant to be a simple example of encoding and decoding audio
28 using Opus. It should make it easy to understand how the Opus API
29 works. For more information, see the full API documentation at:
30 https://www.opus-codec.org/docs/ */
31
32 #include <stdlib.h>
33 #include <errno.h>
34 #include <string.h>
35 #include <opus.h>
36 #include <stdio.h>
37
38 /*The frame size is hardcoded for this sample code but it doesn't have to be*/
39 #define FRAME_SIZE 960
40 #define SAMPLE_RATE 48000
41 #define CHANNELS 2
42 #define APPLICATION OPUS_APPLICATION_AUDIO
43 #define BITRATE 64000
44
45 #define MAX_FRAME_SIZE 6*960
46 #define MAX_PACKET_SIZE (3*1276)
47
main(int argc,char ** argv)48 int main(int argc, char **argv)
49 {
50 char *inFile;
51 FILE *fin;
52 char *outFile;
53 FILE *fout;
54 opus_int16 in[FRAME_SIZE*CHANNELS];
55 opus_int16 out[MAX_FRAME_SIZE*CHANNELS];
56 unsigned char cbits[MAX_PACKET_SIZE];
57 int nbBytes;
58 /*Holds the state of the encoder and decoder */
59 OpusEncoder *encoder;
60 OpusDecoder *decoder;
61 int err;
62
63 if (argc != 3)
64 {
65 fprintf(stderr, "usage: trivial_example input.pcm output.pcm\n");
66 fprintf(stderr, "input and output are 16-bit little-endian raw files\n");
67 return EXIT_FAILURE;
68 }
69
70 /*Create a new encoder state */
71 encoder = opus_encoder_create(SAMPLE_RATE, CHANNELS, APPLICATION, &err);
72 if (err<0)
73 {
74 fprintf(stderr, "failed to create an encoder: %s\n", opus_strerror(err));
75 return EXIT_FAILURE;
76 }
77 /* Set the desired bit-rate. You can also set other parameters if needed.
78 The Opus library is designed to have good defaults, so only set
79 parameters you know you need. Doing otherwise is likely to result
80 in worse quality, but better. */
81 err = opus_encoder_ctl(encoder, OPUS_SET_BITRATE(BITRATE));
82 if (err<0)
83 {
84 fprintf(stderr, "failed to set bitrate: %s\n", opus_strerror(err));
85 return EXIT_FAILURE;
86 }
87 inFile = argv[1];
88 fin = fopen(inFile, "rb");
89 if (fin==NULL)
90 {
91 fprintf(stderr, "failed to open input file: %s\n", strerror(errno));
92 return EXIT_FAILURE;
93 }
94
95
96 /* Create a new decoder state. */
97 decoder = opus_decoder_create(SAMPLE_RATE, CHANNELS, &err);
98 if (err<0)
99 {
100 fprintf(stderr, "failed to create decoder: %s\n", opus_strerror(err));
101 return EXIT_FAILURE;
102 }
103 outFile = argv[2];
104 fout = fopen(outFile, "wb");
105 if (fout==NULL)
106 {
107 fprintf(stderr, "failed to open output file: %s\n", strerror(errno));
108 return EXIT_FAILURE;
109 }
110
111 while (1)
112 {
113 int i;
114 unsigned char pcm_bytes[MAX_FRAME_SIZE*CHANNELS*2];
115 int frame_size;
116 size_t samples;
117
118 /* Read a 16 bits/sample audio frame. */
119 samples = fread(pcm_bytes, sizeof(short)*CHANNELS, FRAME_SIZE, fin);
120
121 /* For simplicity, only read whole frames. In a real application,
122 * we'd pad the final partial frame with zeroes, record the exact
123 * duration, and trim the decoded audio to match.
124 */
125 if (samples != FRAME_SIZE)
126 {
127 break;
128 }
129
130 /* Convert from little-endian ordering. */
131 for (i=0;i<CHANNELS*FRAME_SIZE;i++)
132 {
133 in[i]=pcm_bytes[2*i+1]<<8|pcm_bytes[2*i];
134 }
135
136 /* Encode the frame. */
137 nbBytes = opus_encode(encoder, in, FRAME_SIZE, cbits, MAX_PACKET_SIZE);
138 if (nbBytes<0)
139 {
140 fprintf(stderr, "encode failed: %s\n", opus_strerror(nbBytes));
141 return EXIT_FAILURE;
142 }
143
144
145 /* Decode the data. In this example, frame_size will be constant because
146 the encoder is using a constant frame size. However, that may not
147 be the case for all encoders, so the decoder must always check
148 the frame size returned. */
149 frame_size = opus_decode(decoder, cbits, nbBytes, out, MAX_FRAME_SIZE, 0);
150 if (frame_size<0)
151 {
152 fprintf(stderr, "decoder failed: %s\n", opus_strerror(frame_size));
153 return EXIT_FAILURE;
154 }
155
156 /* Convert to little-endian ordering. */
157 for(i=0;i<CHANNELS*frame_size;i++)
158 {
159 pcm_bytes[2*i]=out[i]&0xFF;
160 pcm_bytes[2*i+1]=(out[i]>>8)&0xFF;
161 }
162 /* Write the decoded audio to file. */
163 fwrite(pcm_bytes, sizeof(short), frame_size*CHANNELS, fout);
164 }
165 /*Destroy the encoder state*/
166 opus_encoder_destroy(encoder);
167 opus_decoder_destroy(decoder);
168 fclose(fin);
169 fclose(fout);
170 return EXIT_SUCCESS;
171 }
172