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include only the necessary values in logs

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Vadim 2025-01-19 21:41:51 +01:00
parent fd97fc7fef
commit 4db83e5c02
1 changed files with 14 additions and 9 deletions
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23
lib/utils/ev_from_bytes.dart
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@ -4,24 +4,29 @@ import 'package:exif/exif.dart';
import 'package:flutter/foundation.dart';
import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';
const String _isoExifKey = 'EXIF ISOSpeedRatings';
const String _apertureExifKey = 'EXIF FNumber';
const String _shutterSpeedExifKey = 'EXIF ExposureTime';
Future<double> evFromImage(Uint8List bytes) async {
final tags = await readExifFromBytes(bytes);
final iso = double.tryParse("${tags["EXIF ISOSpeedRatings"]}");
final apertureValueRatio = (tags["EXIF FNumber"]?.values as IfdRatios?)?.ratios.first;
final speedValueRatio = (tags["EXIF ExposureTime"]?.values as IfdRatios?)?.ratios.first;
final iso = double.tryParse("${tags[_isoExifKey]}");
final apertureValueRatio = (tags[_apertureExifKey]?.values as IfdRatios?)?.ratios.first;
final speedValueRatio = (tags[_shutterSpeedExifKey]?.values as IfdRatios?)?.ratios.first;
if (iso == null || apertureValueRatio == null || speedValueRatio == null) {
throw ArgumentError(
'Error parsing EXIF: ${tags.keys.join(', ')}',
'Error parsing EXIF',
[
if (iso == null) 'EXIF ISOSpeedRatings',
if (apertureValueRatio == null) 'EXIF FNumber',
if (speedValueRatio == null) 'EXIF ExposureTime',
if (iso == null) '$_isoExifKey: "${tags[_isoExifKey]?.printable}"',
if (apertureValueRatio == null) '$_apertureExifKey: $apertureValueRatio',
if (speedValueRatio == null) '$_shutterSpeedExifKey: $speedValueRatio',
].join(', '),
);
}
final aperture = apertureValueRatio.numerator / apertureValueRatio.denominator;
final speed = speedValueRatio.numerator / speedValueRatio.denominator;
final aperture = apertureValueRatio.toDouble();
final speed = speedValueRatio.toDouble();
return log2(math.pow(aperture, 2)) - log2(speed) - log2(iso / 100);
}