public async Task <ImageInfo> Analyse(Stream imageStream)
{
// ReSharper disable once UseAwaitUsing
if (imageStream.Length == 0)
{
throw new Exception("Image stream is 0");
}
byte[] shaHash;
using (var sha256Hasher = SHA256.Create())
{
shaHash = await sha256Hasher.ComputeHashAsync(imageStream);
}
imageStream.Position = 0;
var(image, format) = await SixLabors.ImageSharp.Image.LoadWithFormatAsync <Rgba32>(imageStream);
using (image)
{
var width = image.Width;
var height = image.Height;
var mimeType = format.DefaultMimeType;
var averageHasher = new AverageHash();
var averageHash = averageHasher.Hash(image);
var perceptualHasher = new PerceptualHash();
var perceptualHash = perceptualHasher.Hash(image);
var differenceHasher = new DifferenceHash();
var differenceHash = differenceHasher.Hash(image);
return(new ImageInfo(shaHash, averageHash, differenceHash, perceptualHash, width, height, mimeType));
}
}
public void CreateAndDispose()
{
using (var model = AverageHash.Create())
{
GC.KeepAlive(model);
}
}
public ImageHashFacade(IFileSystem fileSystem)
{
this.fileSystem = fileSystem ?? throw new ArgumentNullException(nameof(fileSystem));
averageHash = new AverageHash();
differenceHash = new DifferenceHash();
perceptualHash = new PerceptualHash();
}
public void CompareSameImage()
{
using (var model = AverageHash.Create())
using (var img1 = Image("lenna.png", ImreadModes.Grayscale))
{
double hash = model.Compare(img1, img1);
Assert.Equal(0, hash, 6);
}
}
public void CompareDifferentImage()
{
using (var model = AverageHash.Create())
using (var img1 = Image("lenna.png", ImreadModes.Grayscale))
using (var img2 = Image("building.jpg", ImreadModes.Grayscale))
{
var size = new Size(256, 256);
using (var scaledImg1 = img1.Resize(size))
using (var scaledImg2 = img2.Resize(size))
{
double hash = model.Compare(scaledImg1, scaledImg2);
Assert.Equal(264411, hash, 6);
}
}
}
public void CalculateImageHashDemo()
{
#region CalculateImageHash
var hashAlgorithm = new AverageHash();
// or one of the other available algorithms:
// var hashAlgorithm = new DifferenceHash();
// var hashAlgorithm = new PerceptualHash();
string filename = "your filename";
using var stream = File.OpenRead(filename);
ulong imageHash = hashAlgorithm.Hash(stream);
#endregion
}
public void CalculateSimilarityDemo()
{
var hashAlgorithm = new AverageHash();
var imageStream1 = new MemoryStream();
var imageStream2 = new MemoryStream();
#region CalculateSimilarity
// calculate the two image hashes
ulong hash1 = hashAlgorithm.Hash(imageStream1);
ulong hash2 = hashAlgorithm.Hash(imageStream2);
double percentageImageSimilarity = CompareHash.Similarity(hash1, hash2);
#endregion
}
public async Task HashAsync()
{
List <Media> medias = await _dbContext.Medias.AsQueryable()
.Where(x =>
x.State == MediaState.Active &&
x.MediaType == MediaType.Image &&
x.ImageHash == null)
.ToListAsync();
var todo = medias.Count;
var hasher = new AverageHash();
foreach (Media media in medias)
{
Console.WriteLine($"{todo} - {media.Id}");
try
{
var fileName = _mediaService.GetFilename(media, MediaFileType.Original);
if (File.Exists(fileName))
{
var hash = hasher.Hash(File.OpenRead(fileName));
UpdateDefinition <Media> update = Builders <Media> .Update.Set(x => x.ImageHash, hash.ToString());
await _dbContext.Medias.UpdateOneAsync(x => x.Id == media.Id, update);
}
else
{
File.WriteAllText($@"C:\MagicMedia\Broken\{media.Id}.txt", $"NOT_FOUND:{fileName}");
}
}
catch (Exception ex)
{
File.WriteAllText($@"C:\MagicMedia\Broken\{media.Id}.txt", $"ERROR:{ex.Message}");
}
todo--;
}
}
private void btnAverageHash_Click(object sender, EventArgs e)
{
try
{
AverageHash aHash1 = new AverageHash(bmpSlika1);
AverageHash aHash2 = new AverageHash(bmpSlika2);
lblHashPrveSlike.Text = "Hash prve slike: " + aHash1.GetHash();
lblHashDrugeSlike.Text = "Hash druge slike:" + aHash2.GetHash();
int brojIstihBitova = AverageHash.IzracunavanjeSlicnihBitova(aHash1.GetHash(), aHash2.GetHash());
lblIstiBitovi.Text = "Isti bitovi:" + " " + brojIstihBitova.ToString();
int brojRazlicitihBitova = AverageHash.IzracunavanjeRazlicitihBitova(aHash1.GetHash(), aHash2.GetHash());
lblRazliciti1.Text = brojRazlicitihBitova.ToString();
double prosjek = AverageHash.IzracunajPostotakSlicnosti(brojIstihBitova, brojRazlicitihBitova, aHash1.GetHash().Length);
lblRazliciti2.Text = prosjek.ToString() + "%";
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Niste uploadali sliku!", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
public void Compute()
{
using (var model = AverageHash.Create())
using (var img = Image("lenna.png"))
using (var hash = new Mat <byte>())
{
model.Compute(img, hash);
Assert.Equal(1, hash.Rows);
Assert.Equal(8, hash.Cols);
Assert.Equal(MatType.CV_8UC1, hash.Type());
var hashArray = hash.ToArray();
Assert.Equal(101, hashArray[0]);
Assert.Equal(121, hashArray[1]);
Assert.Equal(185, hashArray[2]);
Assert.Equal(149, hashArray[3]);
Assert.Equal(205, hashArray[4]);
Assert.Equal(209, hashArray[5]);
Assert.Equal(213, hashArray[6]);
Assert.Equal(112, hashArray[7]);
}
}
public AverageHashTest()
{
sut = new AverageHash();
}
