thedesk/app/node_modules/pngjs/lib/parser-sync.js

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2018-02-19 04:41:25 +11:00
'use strict';
var hasSyncZlib = true;
var zlib = require('zlib');
var inflateSync = require('./sync-inflate');
if (!zlib.deflateSync) {
hasSyncZlib = false;
}
var SyncReader = require('./sync-reader');
var FilterSync = require('./filter-parse-sync');
var Parser = require('./parser');
var bitmapper = require('./bitmapper');
var formatNormaliser = require('./format-normaliser');
module.exports = function(buffer, options) {
if (!hasSyncZlib) {
throw new Error('To use the sync capability of this library in old node versions, please pin pngjs to v2.3.0');
}
var err;
function handleError(_err_) {
err = _err_;
}
var metaData;
function handleMetaData(_metaData_) {
metaData = _metaData_;
}
function handleTransColor(transColor) {
metaData.transColor = transColor;
}
function handlePalette(palette) {
metaData.palette = palette;
}
var gamma;
function handleGamma(_gamma_) {
gamma = _gamma_;
}
var inflateDataList = [];
function handleInflateData(inflatedData) {
inflateDataList.push(inflatedData);
}
var reader = new SyncReader(buffer);
var parser = new Parser(options, {
read: reader.read.bind(reader),
error: handleError,
metadata: handleMetaData,
gamma: handleGamma,
palette: handlePalette,
transColor: handleTransColor,
inflateData: handleInflateData
});
parser.start();
reader.process();
if (err) {
throw err;
}
//join together the inflate datas
var inflateData = Buffer.concat(inflateDataList);
inflateDataList.length = 0;
var inflatedData;
if (metaData.interlace) {
inflatedData = zlib.inflateSync(inflateData);
} else {
var rowSize = ((metaData.width * metaData.bpp * metaData.depth + 7) >> 3) + 1;
var imageSize = rowSize * metaData.height;
inflatedData = inflateSync(inflateData, { chunkSize: imageSize, maxLength: imageSize });
}
inflateData = null;
if (!inflatedData || !inflatedData.length) {
throw new Error('bad png - invalid inflate data response');
}
var unfilteredData = FilterSync.process(inflatedData, metaData);
inflateData = null;
var bitmapData = bitmapper.dataToBitMap(unfilteredData, metaData);
unfilteredData = null;
var normalisedBitmapData = formatNormaliser(bitmapData, metaData);
metaData.data = normalisedBitmapData;
metaData.gamma = gamma || 0;
return metaData;
};