/// <summary> Compares a current and previous version of an image and returns a diff image if they differ </summary>
/// <param name="self">The current version of the image </param>
/// <param name="imgFile"> The file where the previous version of the image is stored in </param>
/// <param name="maxAllowedDiff"> A good value to start testing with would be e.g. 0.0005 </param>
/// <returns> null if the images do not differ, a diff image otherwise </returns>
public static FileEntry Compare(this MagickImage self, FileEntry imgFile, ErrorMetric errorMetric, double maxAllowedDiff)
{
using (MagickImage oldImg = new MagickImage()) {
oldImg.LoadFromFileEntry(imgFile);
double diffValue = self.CompareV2(oldImg, errorMetric, out MagickImage imgWithDifferences);
var diffDetected = diffValue > maxAllowedDiff;
// Log.d($"Visual difference of current scene VS image '{imgFile.Name}' is: {diffValue} vs {maxAllowedDiff} (max allowed diff)");
FileEntry diffFile = imgFile.Parent.GetChild(imgFile.NameWithoutExtension + ".diff" + imgFile.ExtensionWithDot);
imgWithDifferences.SaveToFileEntry(diffFile);
imgWithDifferences.Dispose();
return(diffDetected ? diffFile : null);
}
}