From ad09cba2a6afc55b945fad63217033834e4850d3 Mon Sep 17 00:00:00 2001
From: samfoster <sam.foster@advancednavigation.com>
Date: Fri, 6 Sep 2024 11:01:09 +0800
Subject: [PATCH 1/2] fix indexing for reading rational or srational arrays
---
src/geotiff.js | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/src/geotiff.js b/src/geotiff.js
index 17349a41..20a6549a 100644
--- a/src/geotiff.js
+++ b/src/geotiff.js
@@ -158,11 +158,11 @@ function getValues(dataSlice, fieldType, count, offset) {
);
}
} else { // RATIONAL or SRATIONAL
- for (let i = 0; i < count; i += 2) {
- values[i] = readMethod.call(
+ for (let i = 0; i < count; i++) {
+ values[i * 2] = readMethod.call(
dataSlice, offset + (i * fieldTypeLength),
);
- values[i + 1] = readMethod.call(
+ values[i * 2 + 1] = readMethod.call(
dataSlice, offset + ((i * fieldTypeLength) + 4),
);
}
From da3cdaf59c88f4c0d1912eb75b004cbd6ebe9474 Mon Sep 17 00:00:00 2001
From: Samuel Foster <sam6321@live.com.au>
Date: Sun, 8 Sep 2024 16:15:09 +0800
Subject: [PATCH 2/2] added test for rational arrays
---
test/geotiff.spec.js | 26 +++++++++++++++++++++++++-
1 file changed, 25 insertions(+), 1 deletion(-)
diff --git a/test/geotiff.spec.js b/test/geotiff.spec.js
index bc2e23d1..1ded9f20 100644
--- a/test/geotiff.spec.js
+++ b/test/geotiff.spec.js
@@ -7,7 +7,7 @@ import finalhandler from 'finalhandler';
import AbortController from 'node-abort-controller';
import { dirname } from 'path';
-import { GeoTIFF, fromArrayBuffer, writeArrayBuffer, fromUrls, Pool } from '../dist-module/geotiff.js';
+import { GeoTIFF, fromArrayBuffer, writeArrayBuffer, fromUrls, Pool, globals } from '../dist-module/geotiff.js';
import { makeFetchSource } from '../dist-module/source/remote.js';
import { makeFileSource } from '../dist-module/source/file.js';
import { BlockedSource } from '../dist-module/source/blockedsource.js';
@@ -280,6 +280,30 @@ describe('GeoTIFF', () => {
const image = await tiff.getImage();
await image.readRasters();
});
+
+ it('should parse arrays of rationals correctly', async () => {
+ // For the purposes of this test, we need to parse an array of rationals.
+ // These two fields from EXIF GPSInfo are both arrays of 3 rationals that are suitable for this.
+ globals.fieldTagNames[0x8825] = "GPSInfo";
+ globals.fieldTagNames[0x0002] = "GPSLatitude";
+ globals.fieldTagNames[0x0004] = "GPSLongitude";
+
+ // Contains EXIF data from a JPG image which contains a
+ // GPSInfo IFD that contains the requried GPSLatitude and GPSLongitude fields.
+ const exifTiff = new Uint32Array([
+ 2771273,8,16777229,65540,262144000,16842752,65540,196608000,17760256,524290,11141120,17825792,1114114,11665408,17956864,65539,393216,18481152,65541,12845056,18546688,65541,13369344,19398656,65539,131072,19988480,917506,13893632,20054016,1310722,14811136,34799616,65539,65536,2271805440,65540,16121856,2284126208,65540,49283072,58064896,1634926592,1853191021,1632043111,2037932396,858936096,1953256736,24946,72,1,72,1,942750035,1398298690,1180189494,808583235,809120818,909130297,976760864,842676274,1966137,361114,1,612,361117,1,620,231458,1,2,231463,1,125,495616,4,808596016,167939,20,628,167940,20,648,167952,7,668,167953,7,676,692737,1,684,365058,1,692,692739,1,700,692740,1,708,365061,1,716,233991,1,2,233993,1,0,365066,1,724,168592,4,3552308,168593,4,3552308,168594,4,3552308,499712,4,808464688,237569,1,65535,303106,1,4000,303107,1,3000,238594,1,0,238595,1,0,369668,1,732,238597,1,13,238598,1,0,173088,12,740,0,1,50,220,100,875704370,976826426,807417392,942815800,3748410,875704370,976826426,807417392,942815800,3748410,976760875,12336,976760875,12336,1,50,227,100,260,100,0,100,227,100,220,100,100,100,1479684427,809848915,5069105,65542,131074,5439488,131072,196613,54394880,196608,131074,4521984,262144,196613,55967744,327680,65539,0,393216,65541,57540608,0,2031616,65536,3342336,65536,2523332608,1111491281,7536655,65536,3211264,65536,1907294208,1111490841,15,65536,0
+ ]);
+
+ const tiff = await fromArrayBuffer(exifTiff.buffer);
+ const ifd0 = await tiff.requestIFD(0);
+ expect(ifd0.fileDirectory.GPSInfo).to.equal(752);
+ const gpsIfd = await tiff.parseFileDirectoryAt(ifd0.fileDirectory.GPSInfo);
+ // These fields have 6 components that should be parsed to contain values
+ expect(gpsIfd.fileDirectory.GPSLatitude.length).to.equal(6);
+ expect(gpsIfd.fileDirectory.GPSLongitude.length).to.equal(6);
+ expect(gpsIfd.fileDirectory.GPSLatitude).to.eql(new Uint32Array([31, 1, 51, 1, 47289959, 1000000]));
+ expect(gpsIfd.fileDirectory.GPSLongitude).to.eql(new Uint32Array([115, 1, 49, 1, 18444719, 1000000]));
+ });
});
describe('n-bit uint tests', () => {