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const DIGIT_CHARACTERS = [
'0',
'1',
'2',
'3',
'4',
'5',
'6',
'7',
'8',
'9',
'A',
'B',
'C',
'D',
'E',
'F',
'G',
'H',
'I',
'J',
'K',
'L',
'M',
'N',
'O',
'P',
'Q',
'R',
'S',
'T',
'U',
'V',
'W',
'X',
'Y',
'Z',
'a',
'b',
'c',
'd',
'e',
'f',
'g',
'h',
'i',
'j',
'k',
'l',
'm',
'n',
'o',
'p',
'q',
'r',
's',
't',
'u',
'v',
'w',
'x',
'y',
'z',
'#',
'$',
'%',
'*',
'+',
',',
'-',
'.',
':',
';',
'=',
'?',
'@',
'[',
']',
'^',
'_',
'{',
'|',
'}',
'~',
];
export const decode83 = (str) => {
let value = 0;
let c, digit;
for (let i = 0; i < str.length; i++) {
c = str[i];
digit = DIGIT_CHARACTERS.indexOf(c);
value = value * 83 + digit;
}
return value;
};
export const intToRGB = int => ({
r: Math.max(0, (int >> 16)),
g: Math.max(0, (int >> 8) & 255),
b: Math.max(0, (int & 255)),
});
export const getAverageFromBlurhash = blurhash => {
if (!blurhash) {
return null;
}
return intToRGB(decode83(blurhash.slice(2, 6)));
};
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