/// <summary>Parses <see cref="ExifSubIfdDirectory" /> metadata and saves it to the <see cref="Photo" />.</summary>
/// <param name="directory">Directory containing the F-number, ISO, shutter speed, datetime original and focal length metadata.</param>
/// <param name="photo">Photo object used for storing metadata.</param>
public static void Parse(this ExifSubIfdDirectory directory, Photo photo)
{
if (directory is null || photo is null)
{
return;
}
if (directory.TryGetSingle(ExifDirectoryBase.TagFNumber, out var fNum))
{
photo.FNumber = fNum;
}
if (directory.TryGetInt16(ExifDirectoryBase.TagIsoEquivalent, out var iso))
{
photo.Iso = iso;
}
if (directory.TryGetSingle(ExifDirectoryBase.TagShutterSpeed, out var apexValue))
{
photo.ShutterSpeed = MetadataConverter.ComputeShutterSpeed(apexValue);
}
if (directory.TryGetDateTime(ExifDirectoryBase.TagDateTimeOriginal, out var dateTimeOriginal))
{
photo.DateTimeOriginal = dateTimeOriginal;
}
if (directory.TryGetSingle(ExifDirectoryBase.TagFocalLength, out var focalLength))
{
photo.FocalLength = focalLength;
}
}
public void ComputeShutterSpeed_GreaterThanOneValue()
{
var expected = "1/4 sec"; // exp(2 * log(2)) = 4
var actual = MetadataConverter.ComputeShutterSpeed(2);
Assert.Equal(expected, actual);
}
public void ComputeShutterSpeed_LessOrEqualToOneValue()
{
// Align the data formatting for testing
Thread.CurrentThread.CurrentCulture = CultureInfo.GetCultureInfo("en-US");
var expected = "0.5 sec"; // round((1 / exp(1 * log(2))) * 10) / 10 = 0.5
var actual = MetadataConverter.ComputeShutterSpeed(1);
Assert.Equal(expected, actual);
}