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Analysis of header of WAV audio file

The numbers 1 through 100 below followed by a colon ( : )
mark bytes 1 through 100 in a WAVE audio file,
with extension .wav .
The decimal value of the character is first given,
followed by its ASCII value, or “Extended ASCII”
for values 128-255.

I’ve followed the explanations from topherlee dot com
at the Web page:

< http://www.topherlee.com/software/pcm-tut-wavformat.html >

in the table following the line:

” The header of a WAV (RIFF) file is 44 bytes long and has the following format: ”
For large integer values, the base used is 256,
so that sample rate:

68
172
0
0

reads as:
68 + 172*256 = 44100 (sampling rate)

and as another example, in positions 41-44,
the “File size (data)” section, or:

0
122
103
25

reads as:
0 + 122*256 + 103*256*256 + 25*256*256*256 = 426,211,840.

David Bernier

January 3 2017

Analysis of header of wave audio file:

1: 82 = R
2: 73 = I
3: 70 = F
4: 70 = F
Marks the file as a riff file.

5: 36 = $
6: 122 = z
7: 103 = g
8: 25 = EM
Size of the overall file, in bytes = 426,211,876 bytes.
( 426,211,884 bytes according to “ls”, extra 8 bytes .)
9: 87 = W
10: 65 = A
11: 86 = V
12: 69 = E
File Type Header = “WAVE”
13: 102 = f
14: 109 = m
15: 116 = t
16: 32 = Space
Format chunk marker
17: 16 = DLE
18: 0 = NULL
19: 0 = NULL
20: 0 = NULL
Length of format data = 16 bits/sample
For each channel.

21: 1 = SOH
22: 0 = NULL
Type of format = 1 , for PCM

23: 2 = STX
24: 0 = NULL
Number of Channels = 2

25: 68 = D
26: 172 = Extended ASCII
27: 0 = NULL
28: 0 = NULL
Sample Rate = 44100

29: 16 = DLE
30: 177 = Extended ASCII
31: 2 = STX
32: 0 = NULL
(Sample Rate * BitsPerSample * Channels)/ 8 = 176,400 bytes/second
33: 4 = EOT
34: 0 = NULL
(BitsPerSample * Channels) / 8 = 4.

35: 16 = DLE
36: 0 = NULL
Bits per sample = 16.
37: 100 = d
38: 97 = a
39: 116 = t
40: 97 = a
“data” chunk header.

41: 0 = NULL
42: 122 = z
43: 103 = g
44: 25 = EM
File size = 426,211,840 bytes of DATA .
+ 44 bytes of Header = 426,211,884 bytes in TOTAL. Check Ok.
HEADER DONE.

DATA BELOW: chunked in bytes of 8 bits.

45: 220 = Extended ASCII
46: 0 = NULL
47: 208 = Extended ASCII
48: 0 = NULL

49: 241 = Extended ASCII
50: 1 = SOH
51: 252 = Extended ASCII
52: 1 = SOH

53: 244 = Extended ASCII
54: 0 = NULL
55: 235 = Extended ASCII
56: 0 = NULL

57: 62 = >
58: 0 = NULL
59: 97 = a
60: 0 = NULL

61: 177 = Extended ASCII
62: 252 = Extended ASCII
63: 181 = Extended ASCII
64: 252 = Extended ASCII

65: 74 = J
66: 248 = Extended ASCII
67: 131 = Extended ASCII
68: 248 = Extended ASCII

69: 32 = Space
70: 246 = Extended ASCII
71: 1 = SOH
72: 246 = Extended ASCII

73: 23
74: 243
75: 50
76: 243

77: 193
78: 240
79: 214
80: 240

81: 152
82: 238
83: 133
84: 238

85: 255
86: 235
87: 58
88: 236

89: 202
90: 235
91: 165
92: 235

93: 202
94: 235
95: 236
96: 235

97: 53
98: 235
99: 38
100: 235

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Written by meditationatae

January 4, 2017 at 5:08 am

Posted in History

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