|
1
|
|
|
/* |
|
2
|
|
|
* to-bytes: convert bytes to numbers and strings. |
|
3
|
|
|
* Copyright (c) 2017 Rafael da Silva Rocha. |
|
4
|
|
|
* https://github.com/rochars/byte-data |
|
5
|
|
|
*/ |
|
6
|
|
|
|
|
7
|
|
|
const intBits = require("int-bits"); |
|
|
|
|
|
|
8
|
|
|
const pad = require("../src/byte-padding.js"); |
|
9
|
|
|
const endianness = require("endianness"); |
|
10
|
|
|
const writer = require("../src/write-bytes.js"); |
|
11
|
|
|
const bitDepths = require("../src/bit-depth.js"); |
|
12
|
|
|
|
|
13
|
|
|
/** |
|
14
|
|
|
* Turn numbers and strings to bytes. |
|
15
|
|
|
* @param {!Array<number>|string} numbers float64 numbers. |
|
16
|
|
|
* @param {number} bitDepth The desired bitDepth for the data. |
|
17
|
|
|
* @param {Object} params The params. defaults to: |
|
18
|
|
|
* - "float", defaults to false, true for floats. |
|
19
|
|
|
* float is available for 16, 32 and 64 bit depths. |
|
20
|
|
|
* - "base", defaults to 10, can be 2, 10 or 16 |
|
21
|
|
|
* - "char", defaults to false, true for strings |
|
22
|
|
|
* - "be", defaults to false, true for big endian |
|
23
|
|
|
* @return {!Array<number>} the bytes. |
|
24
|
|
|
*/ |
|
25
|
|
|
function toBytes(numbers, bitDepth, params={}) { |
|
26
|
|
|
let base = 10; |
|
27
|
|
|
if ("base" in params) { |
|
28
|
|
|
base = params.base; |
|
29
|
|
|
} |
|
30
|
|
|
let isBigEndian = params.be; |
|
31
|
|
|
let isChar = params.char; |
|
32
|
|
|
let isFloat = params.float; |
|
33
|
|
|
let bytes = writeBytes(numbers, isChar, isFloat, isBigEndian, bitDepth); |
|
34
|
|
|
outputToBase(bytes, bitDepth, base); |
|
35
|
|
|
return bytes; |
|
36
|
|
|
} |
|
37
|
|
|
|
|
38
|
|
|
/** |
|
39
|
|
|
* Turn the output to the correct base. |
|
40
|
|
|
* @param {!Array<number>} bytes The bytes. |
|
41
|
|
|
* @param {number} bitDepth The bitDepth of the data. |
|
42
|
|
|
* @param {number} base The base. |
|
43
|
|
|
*/ |
|
44
|
|
|
function outputToBase(bytes, bitDepth, base) { |
|
45
|
|
|
if (bitDepth == 4) { |
|
46
|
|
|
bytesToBase(bytes, base, pad.paddingNibble); |
|
47
|
|
|
} else if (bitDepth == 2) { |
|
48
|
|
|
bytesToBase(bytes, base, pad.paddingCrumb); |
|
49
|
|
|
} else if(bitDepth == 1) { |
|
50
|
|
|
bytesToBase(bytes, base, function(){}); |
|
51
|
|
|
}else { |
|
52
|
|
|
bytesToBase(bytes, base); |
|
53
|
|
|
} |
|
54
|
|
|
} |
|
55
|
|
|
|
|
56
|
|
|
/** |
|
57
|
|
|
* Write values as bytes. |
|
58
|
|
|
* @param {!Array<number>|string} numbers The values. |
|
59
|
|
|
* @param {boolean} isChar True if it is a string. |
|
60
|
|
|
* @param {boolean} isFloat True if it is a IEEE floating point number. |
|
61
|
|
|
* @param {boolean} isBigEndian True if the bytes should be big enadian. |
|
62
|
|
|
* @param {number} bitDepth The bitDepth of the data. |
|
63
|
|
|
* @return {!Array<number>} the bytes. |
|
64
|
|
|
*/ |
|
65
|
|
|
function writeBytes(numbers, isChar, isFloat, isBigEndian, bitDepth) { |
|
66
|
|
|
let bitWriter; |
|
67
|
|
|
if (isChar) { |
|
68
|
|
|
bitWriter = writer.writeString; |
|
69
|
|
|
} else { |
|
70
|
|
|
bitWriter = writer['write' + bitDepth + 'Bit' + (isFloat ? "Float" : "")]; |
|
71
|
|
|
} |
|
72
|
|
|
let i = 0; |
|
73
|
|
|
let j = 0; |
|
74
|
|
|
let len = numbers.length; |
|
75
|
|
|
let bytes = []; |
|
76
|
|
|
while (i < len) { |
|
77
|
|
|
j = bitWriter(bytes, numbers, i, j); |
|
78
|
|
|
i++; |
|
79
|
|
|
} |
|
80
|
|
|
if (isBigEndian) { |
|
81
|
|
|
endianness.endianness(bytes, bitDepths.bitDepthOffsets[bitDepth]); |
|
82
|
|
|
} |
|
83
|
|
|
return bytes; |
|
84
|
|
|
} |
|
85
|
|
|
|
|
86
|
|
|
/** |
|
87
|
|
|
* Turn bytes to base. |
|
88
|
|
|
* @param {!Array<string>|!Array<number>} bytes The bytes. |
|
89
|
|
|
* @param {number} base The base. |
|
90
|
|
|
* @param {Function} padFunction The function to use for padding. |
|
91
|
|
|
*/ |
|
92
|
|
|
function bytesToBase(bytes, base, padFunction=pad.padding) { |
|
93
|
|
|
if (base != 10) { |
|
94
|
|
|
let i = 0; |
|
95
|
|
|
let len = bytes.length; |
|
96
|
|
|
while (i < len) { |
|
97
|
|
|
bytes[i] = bytes[i].toString(base); |
|
98
|
|
|
padFunction(bytes, base, i); |
|
99
|
|
|
i++; |
|
100
|
|
|
} |
|
101
|
|
|
} |
|
102
|
|
|
} |
|
103
|
|
|
|
|
104
|
|
|
module.exports.toBytes = toBytes; |
|
105
|
|
|
|
rochars /
byte-data
Loading history...