80 lines
1.7 KiB
JavaScript
80 lines
1.7 KiB
JavaScript
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var exif = require('./exif');
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var date = require('./date');
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var degreeTags = [{
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section: exif.GPSIFD,
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type: 0x0002,
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name: 'GPSLatitude',
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refType: 0x0001,
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refName: 'GPSLatitudeRef',
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posVal: 'N'
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},
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{
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section: exif.GPSIFD,
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type: 0x0004,
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name: 'GPSLongitude',
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refType: 0x0003,
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refName: 'GPSLongitudeRef',
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posVal: 'E'
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}];
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var dateTags = [{
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section: exif.SubIFD,
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type: 0x0132,
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name: 'ModifyDate'
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},
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{
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section: exif.SubIFD,
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type: 0x9003,
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name: 'DateTimeOriginal'
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},
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{
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section: exif.SubIFD,
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type: 0x9004,
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name: 'CreateDate'
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},
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{
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section: exif.SubIFD,
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type: 0x0132,
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name : 'ModifyDate',
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}];
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module.exports = {
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castDegreeValues: function(getTagValue, setTagValue) {
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degreeTags.forEach(function(t) {
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var degreeVal = getTagValue(t);
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if(degreeVal) {
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var degreeRef = getTagValue({section: t.section, type: t.refType, name: t.refName});
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var degreeNumRef = degreeRef === t.posVal ? 1 : -1;
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var degree = (degreeVal[0] + (degreeVal[1] / 60) + (degreeVal[2] / 3600)) * degreeNumRef;
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setTagValue(t, degree);
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}
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});
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},
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castDateValues: function(getTagValue, setTagValue) {
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dateTags.forEach(function(t) {
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var dateStrVal = getTagValue(t);
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if(dateStrVal) {
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//some easy checks to determine two common date formats
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var timestamp = date.parseExifDate(dateStrVal);
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if(typeof timestamp !== 'undefined') {
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setTagValue(t, timestamp);
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}
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}
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});
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},
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simplifyValue: function(values, format) {
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if(Array.isArray(values)) {
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values = values.map(function(value) {
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if(format === 10 || format === 5) {
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return value[0] / value[1];
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}
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return value;
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});
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if(values.length === 1) {
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values = values[0];
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}
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}
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return values;
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}
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};
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