Don't use fraction for exposure times > 0.25, round to one dec

#270
mattiasw · Feb 4, 2024 · 2779d3c · 2779d3c
1 parent 9e21369
commit 2779d3c
Show file tree

Hide file tree

Showing 4 changed files with 15 additions and 4 deletions.
diff --git a/dist/exif-reader.js b/dist/exif-reader.js
diff --git a/dist/exif-reader.js.map b/dist/exif-reader.js.map
diff --git a/src/tag-names-common.js b/src/tag-names-common.js
@@ -82,8 +82,12 @@ export default {
         return 'Unknown';
     },
     ExposureTime(value) {
-        if (value[0] >= value[1]) {
-            return `${Math.round(value[0] / value[1])}`;
+        if (value[0] / value[1] > 0.25) {
+            const decimal = value[0] / value[1];
+            if (Number.isInteger(decimal)) {
+                return '' + decimal;
+            }
+            return decimal.toFixed(1);
         }
         if (value[0] !== 0) {
             return `1/${Math.round(value[1] / value[0])}`;

diff --git a/test/unit/tag-names-exif-ifd-spec.js b/test/unit/tag-names-exif-ifd-spec.js
@@ -14,6 +14,13 @@ describe('tag-names-exif-ifd', () => {
         expect(TagNamesExifIfd[0x829a].description([6, 1])).to.equal('6');
         expect(TagNamesExifIfd[0x829a].description([1, 1])).to.equal('1');
         expect(TagNamesExifIfd[0x829a].description([0, 1000])).to.equal('0/1000');
+        expect(TagNamesExifIfd[0x829a].description([8, 10])).to.equal('0.8');
+        expect(TagNamesExifIfd[0x829a].description([1, 4])).to.equal('1/4');
+        expect(TagNamesExifIfd[0x829a].description([1, 3])).to.equal('0.3');
+        expect(TagNamesExifIfd[0x829a].description([100, 399])).to.equal('0.3');
+        expect(TagNamesExifIfd[0x829a].description([13, 10])).to.equal('1.3');
+        expect(TagNamesExifIfd[0x829a].description([15, 10])).to.equal('1.5');
+        expect(TagNamesExifIfd[0x829a].description([4, 3]).substring(0, 6)).to.equal('1.3');
     });
 
     it('should have tag FNumber', () => {