private static IEnumerable<string> TryDeduceMatchingCandidateSnapshot(
ImageWrapper transformedOriginalSnapshot,
IEnumerable<string> candidateSnapshots,
Func<ImageWrapper, Maybe<ImageWrapper>> candidateTranform
)
{
var candidateResultList = new ConcurrentBag<Tuple<string, int>>();
using (var originaImageAsLockbit = new LockBitImage(transformedOriginalSnapshot.Image))
{
Parallel.ForEach(candidateSnapshots, candidateSnapshot =>
{
var candidateComparisonResult = from loadedCandidateSnapshot in TryLoadImage(candidateSnapshot)
from transformedCandidate in candidateTranform.Invoke(loadedCandidateSnapshot)
let candidateLockbitImage = new LockBitImage(transformedCandidate.Image)
let similarityIndex = SimilarityCalculator.CalculateSimilarityIndex(
originaImageAsLockbit,
candidateLockbitImage
)
select CommonFunctions.ExecThenDispose(
() => Tuple.Create<string, int>(candidateSnapshot, similarityIndex),
loadedCandidateSnapshot,
transformedCandidate,
candidateLockbitImage
);
candidateComparisonResult.Apply(i => candidateResultList.Add(i));
});
}
return from candidateTuple in candidateResultList
where candidateTuple.Item2 >= 69
select candidateTuple.Item1;
}
/// <summary>
/// Calculate the similarity between two images
/// </summary>
/// <remarks>
/// Images that are not the same size will always return a result of 0, as they cannot
/// be the same.
/// </remarks>
/// <param name="original">The original image to compare against</param>
/// <param name="candidate">The candidate image to compare with the original</param>
/// <returns>An integer, from 0-100 indicating how similar the two images are</returns>
public static int CalculateSimilarityIndex(LockBitImage original, LockBitImage candidate)
{
// Images that are not the same size are immediately discounted
if (original.Width != candidate.Width || original.Height != candidate.Height)
{
return 0;
}
return (int)(SSIMCalculator.Compute(original, candidate) * 100);
}
public GaussianBlurTransformation(Image sourceImage, int radius)
{
_disposed = false;
_sourceImage = new LockBitImage(sourceImage);
_radius = radius;
}
