Wave Header erzeugen

1private byte[] getWaveHeader(int sampleRate, int bitrate, int channels, int totalAudioLength)
2 {
3 byte[] header = new byte[44];
4
5 int totalDataLen = header.length - 8 + totalAudioLength;
6 int byterate = ((sampleRate * bitrate) / 8);
7
8
9 header[0] = 'R'; // RIFF/WAVE header
10 header[1] = 'I';
11 header[2] = 'F';
12 header[3] = 'F';
13 header[4] = (byte) (totalDataLen & 0xff);
14 header[5] = (byte) ((totalDataLen >> 8) & 0xff);
15 header[6] = (byte) ((totalDataLen >> 16) & 0xff);
16 header[7] = (byte) ((totalDataLen >> 24) & 0xff);
17 header[8] = 'W';
18 header[9] = 'A';
19 header[10] = 'V';
20 header[11] = 'E';
21 header[12] = 'f'; // 'fmt ' chunk
22 header[13] = 'm';
23 header[14] = 't';
24 header[15] = ' ';
25 header[16] = 16; // 4 bytes: size of 'fmt ' chunk
26 header[17] = 0;
27 header[18] = 0;
28 header[19] = 0;
29 header[20] = 1; // format = 1
30 header[21] = 0;
31 header[22] = (byte) channels;
32 header[23] = 0;
33 header[24] = (byte) (sampleRate & 0xff);
34 header[25] = (byte) ((sampleRate >> 8) & 0xff);
35 header[26] = (byte) ((sampleRate >> 16) & 0xff);
36 header[27] = (byte) ((sampleRate >> 24) & 0xff);
37 header[28] = (byte) (byterate & 0xff);
38 header[29] = (byte) ((byterate >> 8) & 0xff);
39 header[30] = (byte) ((byterate >> 16) & 0xff);
40 header[31] = (byte) ((byterate >> 24) & 0xff);
41 header[32] = (byte) (bitrate / 8); // block align
42 header[33] = 0;
43 header[34] = (byte) bitrate; // bits per sample
44 header[35] = 0;
45 header[36] = 'd';
46 header[37] = 'a';
47 header[38] = 't';
48 header[39] = 'a';
49 header[40] = (byte) (totalAudioLength & 0xff);
50 header[41] = (byte) ((totalAudioLength >> 8) & 0xff);
51 header[42] = (byte) ((totalAudioLength >> 16) & 0xff);
52 header[43] = (byte) ((totalAudioLength >> 24) & 0xff);
53
54 return header;
55 }