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/* |
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* to-bytes: bytes to numbers and strings. |
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* Copyright (c) 2017 Rafael da Silva Rocha. |
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* https://github.com/rochars/byte-data |
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*/ |
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const helpers = require("../src/helpers.js"); |
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/** |
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* Turn numbers and strings to bytes. |
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* @param {!Array<number>|number|string} values The data. |
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* @param {Object} type One of the available types. |
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* @return {!Array<number>|!Array<string>|Uint8Array} the data as a byte buffer. |
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*/ |
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function toBytes(values, type) { |
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let bytes = writeBytes(values, type); |
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helpers.makeBigEndian(bytes, type); |
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helpers.outputToBase(bytes, type.bits, type.base); |
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helpers.fixFloat16Endianness(bytes, type); |
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return bytes; |
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} |
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/** |
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* Write values as bytes. |
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* @param {!Array<number>|number|string} values The data. |
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* @param {Object} type One of the available types. |
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* @return {!Array<number>} the bytes. |
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*/ |
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function writeBytes(values, type) { |
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let i = 0; |
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let j = 0; |
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let len = values.length; |
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let bytes = []; |
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while (i < len) { |
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j = type.writer(bytes, checkOverflow(values[i], type), j); |
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i++; |
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} |
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return bytes; |
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} |
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/** |
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* Limit the value according to the bit depth in case of |
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* overflow or underflow. |
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* @param {!Array<number>|number|string} value The data. |
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* @param {Object} type The maximum value. |
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*/ |
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function checkOverflow(value, type) { |
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if (!type.float) { |
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if (value > type.max) { |
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value = type.max; |
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} else if(value < type.min) { |
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value = type.min; |
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} |
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} |
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return value; |
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} |
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module.exports.toBytes = toBytes; |
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