Make EXIF parsing more compatible

__tests__/exif.test.ts

@@ -1,6 +1,25 @@
-import { formatExposureCompensation, formatExposureTime } from '@/utility/exif';
+import {
+  convertApertureValueToFNumber,
+  formatExposureCompensation,
+  formatExposureTime,
+} from '@/utility/exif';
 
 describe('EXIF', () => {
+  describe('converts', () => {
+    it('aperture value to f-number', () => {
+      expect(convertApertureValueToFNumber('0')).toBe('1');
+      expect(convertApertureValueToFNumber('1')).toBe('1.4');
+      expect(convertApertureValueToFNumber('2')).toBe('2');
+      expect(convertApertureValueToFNumber('3')).toBe('2.8');
+      expect(convertApertureValueToFNumber('4')).toBe('4');
+      expect(convertApertureValueToFNumber('5')).toBe('5.6');
+      expect(convertApertureValueToFNumber('6')).toBe('8');
+      expect(convertApertureValueToFNumber('7')).toBe('11');
+      expect(convertApertureValueToFNumber('8')).toBe('16');
+      expect(convertApertureValueToFNumber('9')).toBe('22');
+      expect(convertApertureValueToFNumber('10')).toBe('32');
+    });
+  });
   describe('formats', () => {
     it('exposure time', () => {
       expect(formatExposureTime(0)).toBe(undefined);

src/photo/form/index.ts

@@ -6,7 +6,11 @@ import {
   generateLocalNaivePostgresString,
   generateLocalPostgresString,
 } from '@/utility/date';
-import { getAspectRatioFromExif, getOffsetFromExif } from '@/utility/exif';
+import {
+  convertApertureValueToFNumber,
+  getAspectRatioFromExif,
+  getOffsetFromExif,
+} from '@/utility/exif';
 import { roundToNumber } from '@/utility/number';
 import { convertStringToArray } from '@/utility/string';
 import { generateNanoid } from '@/utility/nanoid';
@@ -199,8 +203,11 @@ export const convertExifToFormData = (
   focalLengthIn35MmFormat: data.tags?.FocalLengthIn35mmFormat?.toString(),
   lensMake: data.tags?.LensMake,
   lensModel: data.tags?.LensModel,
-  fNumber: data.tags?.FNumber?.toString(),
+  fNumber: (
-  iso: data.tags?.ISO?.toString(),
+    data.tags?.FNumber?.toString() ||
+    convertApertureValueToFNumber(data.tags?.ApertureValue)
+  ),
+  iso: data.tags?.ISO?.toString() || data.tags?.ISOSpeed?.toString(),
   exposureTime: data.tags?.ExposureTime?.toString(),
   exposureCompensation: data.tags?.ExposureCompensation?.toString(),
   latitude:

src/utility/exif.ts

@@ -31,6 +31,36 @@ export const getAspectRatioFromExif = (data: ExifData): number => {
   }
 };
 
+export const convertApertureValueToFNumber = (
+  apertureValue?: string
+): string | undefined => {
+  if (apertureValue) {
+    const aperture = parseInt(apertureValue);
+    if (aperture <= 10) {
+      switch (aperture) {
+      case 0: return '1';
+      case 1: return '1.4';
+      case 2: return '2';
+      case 3: return '2.8';
+      case 4: return '4';
+      case 5: return '5.6';
+      case 6: return '8';
+      case 7: return '11';
+      case 8: return '16';
+      case 9: return '22';
+      case 10: return '32';
+      }
+    } else {
+      const value = Math.round(Math.pow(2, aperture / 2.0) * 10) / 10;
+      return Number.isInteger(value)
+        ? value.toFixed(0)
+        : value.toFixed(1);
+    }
+  } else {
+    return undefined;
+  }
+};
+
 export const formatAperture = (aperture?: number) =>
   aperture
     ? `ƒ/${roundToString(aperture)}`