bin-utils.js
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/**
* @file bin-utils.js
*/
/**
* convert a TimeRange to text
*
* @param {TimeRange} range the timerange to use for conversion
* @param {Number} i the iterator on the range to convert
*/
const textRange = function(range, i) {
return range.start(i) + '-' + range.end(i);
};
/**
* format a number as hex string
*
* @param {Number} e The number
* @param {Number} i the iterator
*/
const formatHexString = function(e, i) {
let value = e.toString(16);
return '00'.substring(0, 2 - value.length) + value + (i % 2 ? ' ' : '');
};
const formatAsciiString = function(e) {
if (e >= 0x20 && e < 0x7e) {
return String.fromCharCode(e);
}
return '.';
};
/**
* Creates an object for sending to a web worker modifying properties that are TypedArrays
* into a new object with seperated properties for the buffer, byteOffset, and byteLength.
*
* @param {Object} message
* Object of properties and values to send to the web worker
* @return {Object}
* Modified message with TypedArray values expanded
* @function createTransferableMessage
*/
const createTransferableMessage = function(message) {
const transferable = {};
Object.keys(message).forEach((key) => {
const value = message[key];
if (ArrayBuffer.isView(value)) {
transferable[key] = {
bytes: value.buffer,
byteOffset: value.byteOffset,
byteLength: value.byteLength
};
} else {
transferable[key] = value;
}
});
return transferable;
};
/**
* Returns a unique string identifier for a media initialization
* segment.
*/
const initSegmentId = function(initSegment) {
let byterange = initSegment.byterange || {
length: Infinity,
offset: 0
};
return [
byterange.length, byterange.offset, initSegment.resolvedUri
].join(',');
};
/**
* utils to help dump binary data to the console
*/
const utils = {
hexDump(data) {
let bytes = Array.prototype.slice.call(data);
let step = 16;
let result = '';
let hex;
let ascii;
for (let j = 0; j < bytes.length / step; j++) {
hex = bytes.slice(j * step, j * step + step).map(formatHexString).join('');
ascii = bytes.slice(j * step, j * step + step).map(formatAsciiString).join('');
result += hex + ' ' + ascii + '\n';
}
return result;
},
tagDump(tag) {
return utils.hexDump(tag.bytes);
},
textRanges(ranges) {
let result = '';
let i;
for (i = 0; i < ranges.length; i++) {
result += textRange(ranges, i) + ' ';
}
return result;
},
createTransferableMessage,
initSegmentId
};
export default utils;