Problem with comparing two images using imagemagick in C# - c#

I am using ImageMagick tool in C# to identity two images are simiral or not.
var img1 = new ImageMagick.MagickImage("D:\\test\\img1.jpg");
var img2 = new ImageMagick.MagickImage("D:\\test\\img2.jpg");
var img3 = new ImageMagick.MagickImage("D:\\test\\img3.jpg");
// Return 1 Means Similar Image
if (img2.Compare(img1) == 1)
{
// Here I want to delete Duplicate Image
}
if (img3.Compare(img1) == 1)
{
// Here I don't want to delete because both image different
}
Here are images in sequence.
Please help me with this where I am wrong.
OR
Suggest any other best and quick solution to compare images visually in c#.

Related

How do I open a bitmap without C# changing the PixelFormat? [duplicate]

This question already has answers here:
C# - Loading an indexed color image file correctly
(2 answers)
Closed 3 months ago.
I have a bitmap image, myImage.png say. The png has been saved with pixel format Format8bppIndexed, which is something I specifically chose to do. But when I open it in C# using new Bitmap("myImage.png"), I find that it is provided to me as a bitmap in format Format32bppRgb. This isn't what I want, which is why I didn't save it in that format.
I've written code specifically to do turtle-graphics manipulation of a 256-colour indexed raster image; I don't want to rewrite that code to do it with a 32bpp image; I don't see why I should have to. How do I force C# to open my image and just give it to me as it comes, without converting it to a different pixel format? I need an overload of the Bitmap constructor that tells it, "don't try to be helpful, I know what I'm doing". But I can't see one.
If I load an image that's in Format1bppIndexed, C# doesn't do this - I get the binary PNG just as it is, not converted at all.
Under .NET Framework 4.8 and .NET 6.0 for Windows, all four alternatives work for me.
Resulting format is Format8bppIndexed
var imagePath = "image1.png";
using (var bm1 = new Bitmap(imagePath))
{
Console.WriteLine(bm1.PixelFormat.ToString());
}
using (Stream stream = new FileStream(imagePath, FileMode.Open))
{
var bm2 = new Bitmap(stream);
Console.WriteLine(bm2.PixelFormat.ToString());
}
using (Stream stream = new FileStream(imagePath, FileMode.Open))
{
var bm3 = new Bitmap(stream, useIcm: true);
Console.WriteLine(bm3.PixelFormat.ToString());
}
using (var bm4 = new Bitmap(imagePath, useIcm: true))
{
Console.WriteLine(bm4.PixelFormat.ToString());
}
The question and answer linked by Axel substantially answers the question. Here are some details of how I solved my problem.
The problem occurs when you try to open an 8bpp (256-colour indexed) PNG that has palette entries that specify transparency (alpha values less than 255). It does not matter whether the palette entry is actually used for any pixels in the image; the fact that the palette entry exists is enough to cause the problem. When an 8bpp bitmap is created using the System.Drawing library, it is given a default palette, and this default palette may contain colours with transparency, so it may cause this problem if you do not overwrite those palette entries.
There is no easy fix for the issue if you already have the PNG file or if you need to support transparency. In my case I do not actually need transparency in the images I am working with. It was easy enough for me to change the code that creates the PNG files so that it overwrites all the palette entries with dummy entries that are opaque (alpha values of 255).
public static void SetPalette(Bitmap bmp, int numEntriesExcludingBackground)
{
// Ref. https://stackoverflow.com/a/51111141
var palette = bmp.Palette;
int index = 1;
foreach (var entry in GeneratePaletteEntries(numEntriesExcludingBackground))
{
palette.Entries[index] = entry;
++index;
}
for (; index < palette.Entries.Length; ++index) // *
{ // *
palette.Entries[index] = GenerateDummyPaletteEntry(index); // *
} // *
bmp.Palette = palette;
}
(the "//*" decorates lines that were added to address this problem)

fo-Dicom - How do I extract image frames from the DicomFile

I need to extract all image frames from a DICOM SC using fo-DICOM. I have a test app that extracts and displays the images, which works fine. However, I need to save the individual images to a database, and am running into problems.
I have the following code so far:
public void SetImages(DicomFile dicom, ThumbResults results)
{
var images = new DicomImage(dicom.Dataset);
for(var count = 0; count < images.NumberOfFrames; count++)
{
var image = images.RenderImage(count).As<Bitmap>();
using(var stream = new MemoryStream())
{
image.Save(stream, ImageFormat.Jpeg);
results.Images.Add(Convert.ToBase64String(stream.ToArray()));
}
}
}
I get a DicomImagingException, "Cannot cast to 'Bitmap'" on images.RenderImage. It works in my test code, when I call PictureBox.Image = _image.RenderImage(count).As<Bitmap>(); so I figure RenderImage must be specifically for rendering (as the name implies).
How should I go about extracting individual frames to a string that will be saved to the database?
In case someone else runs into this problem, the issue was the original code was in .NET Framework, but the new code was in .NET Core. In Core, the ImageManager does not use the WindowsImageManager by default, so you need to set it manually.
ImageManager.SetImplementation(WinFormsImageManager.Instance);

c# Novacode.Picture to System.Drawing.Image

I'm reading in a .docx file using the Novacode API, and am unable to create or display any images within the file to a WinForm app due to not being able to convert from a Novacode Picture (pic) or Image to a system image. I've noticed that there's very little info inside the pic itself, with no way to get any pixel data that I can see. So I have been unable to utilize any of the usual conversion ideas.
I've also looked up how Word saves images inside the files as well as Novacode source for any hints and I've come up with nothing.
My question then is is there a way to convert a Novacode Picture to a system one, or should I use something different to gather the image data like OpenXML? If so, would Novacode and OpenXML conflict in any way?
There's also this answer that might be another place to start.
Any help is much appreciated.
Okay. This is what I ended up doing. Thanks to gattsbr for the advice. This only works if you can grab all the images in order, and have descending names for all the images.
using System.IO.Compression; // Had to add an assembly for this
using Novacode;
// Have to specify to remove ambiguous error from Novacode
Dictionary<string, System.Drawing.Image> images = new Dictionary<string, System.Drawing.Image>();
void LoadTree()
{
// In case of previous exception
if(File.Exists("Images.zip")) { File.Delete("Images.zip"); }
// Allow the file to be open while parsing
using(FileStream stream = File.Open("Images.docx", FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
{
using(DocX doc = DocX.Load(stream))
{
// Work rest of document
// Still parse here to get the names of the images
// Might have to drag and drop images into the file, rather than insert through Word
foreach(Picture pic in doc.Pictures)
{
string name = pic.Description;
if(null == name) { continue; }
name = name.Substring(name.LastIndexOf("\\") + 1);
name = name.Substring(0, name.Length - 4);
images[name] = null;
}
// Save while still open
doc.SaveAs("Images.zip");
}
}
// Use temp zip directory to extract images
using(ZipArchive zip = ZipFile.OpenRead("Images.zip"))
{
// Gather all image names, in order
// They're retrieved from the bottom up, so reverse
string[] keys = images.Keys.OrderByDescending(o => o).Reverse().ToArray();
for(int i = 1; ; i++)
{
// Also had to add an assembly for ZipArchiveEntry
ZipArchiveEntry entry = zip.GetEntry(String.Format("word/media/image{0}.png", i));
if(null == entry) { break; }
Stream stream = entry.Open();
images[keys[i - 1]] = new Bitmap(stream);
}
}
// Remove temp directory
File.Delete("Images.zip");
}

LEADTOOLS adding QRBarcode to an existing image

My current code writes a qr code but it over writes my file with just the qr code. I am not sure how to adjust the size of the qr code to be placed in one corner of the document rather than taking up the whole page. Also not sure if the RasterImage.Create means that it creates a new file with just the qr and discard my original file?
Code: - Convert PDF to Bmp to add QR then saving back to PDF
public void PDFFileExample()
{
RasterCodecs codecs1 = new RasterCodecs();
codecs1.Options.Pdf.InitialPath = #"C:\LEADTOOLS 18\Bin\Dotnet4\Win32";
codecs1.Dispose();
RasterCodecs codecs2 = new RasterCodecs();
codecs2.ThrowExceptionsOnInvalidImages = true;
System.Diagnostics.Debug.Assert(codecs2.Options.Pdf.InitialPath == #"C:\LEADTOOLS 18\Bin\Dotnet4\Win32");
string pdfFile = #"C:\QRCodeTesting\bottomRight.pdf";
string destFileName1 = #"C:\QRCodeTesting\bottomRightOutputTemp.pdf";
string destFileName2 = #"C:\QRCodeTesting\bottomRightOutput.bmp";
RasterCodecs codecs = new RasterCodecs();
if (codecs.Options.Pdf.IsEngineInstalled)
{
// Resulting image pixel depth.
codecs.Options.Pdf.Load.DisplayDepth = 24;
codecs.Options.Pdf.Load.GraphicsAlpha = 4;
codecs.Options.Pdf.Load.Password = "";
// Type of font anti-aliasing to use.
codecs.Options.Pdf.Load.TextAlpha = 1;
codecs.Options.Pdf.Load.UseLibFonts = true;
// Horizontal,vertical display resolution in dots per inch.
codecs.Options.RasterizeDocument.Load.XResolution = 150;
codecs.Options.RasterizeDocument.Load.YResolution = 150;
using (RasterImage image = codecs.Load(pdfFile, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1))
{
// Set the PDF version to be v1.4
codecs.Options.Pdf.Save.Version = CodecsRasterPdfVersion.V14;
try
{
// Save the image back as PDF
codecs.Save(image, destFileName1, RasterImageFormat.RasPdf, 24);
}
catch (RasterException ex)
{
if (ex.Code == RasterExceptionCode.FileFormat)
MessageBox.Show(string.Format("Image in file {0} is loaded", destFileName1));
else
{
MessageBox.Show(string.Format("Could not load the file {0}.{1}{2}", destFileName1, Environment.NewLine, ex.Message));
}
}
}
// And load it back before saving it as BMP
using (RasterImage image = codecs.Load(destFileName1))
{
codecs.Save(image, destFileName2, RasterImageFormat.Bmp, image.BitsPerPixel);
writeQRTag(destFileName2);
}
}
else
{
MessageBox.Show("PDF Engine is not found!");
}
// Clean up
codecs.Dispose();
}
QRCode writing Method
private void writeQRTag(string imageFileName)
{
BarcodeEngine engine = new BarcodeEngine();
// Create the image to write the barcodes to
int resolution = 300;
using (RasterImage image = RasterImage.Create((int)(8.5 * resolution), (int)(11.0 * resolution), 1, resolution, RasterColor.FromKnownColor(RasterKnownColor.Red)))
{
// Write two QR barcodes
WriteQRCode(engine.Writer, image, QRBarcodeSymbolModel.Model1AutoSize, "QR Data 1", true);
// Save the image
using (RasterCodecs codecs = new RasterCodecs())
{
codecs.Save(image, imageFileName, RasterImageFormat.CcittGroup4, 1);
}
}
}
This is Maen from LEADTOOLS support.
I checked your code and noticed the following:
1) When you call RasterImage.Create() method, it will create a new RasterImage object that contains an empty red image, which you subsequently pass to the writeQRTag() function then save using the given file name.
When you save it, the red color is replaced by black because the file format you used only supports black and white. Since you're using a new image, the old image is lost (overwritten).
If you want to write the barcode on the image from the original file, you should NOT create a new image. Instead, you need to use the image you already loaded using codecs.Load() and write the barcode on it.
2) The code performs multiple load and save operations. Normally, you don't need to do that unless your application needs the different file formats (PDF, BMP and TIFF).
3) You create different instances of our RasterCodecs object but actually use only one of them. There's no need for 3 of the 4 RasterCodecs objects in the code.
If you still face problems with the code that uses our toolkit, you can send us the details in an email to support#leadtools.com and we will try to help you.

Generating a multipage TIFF is not working

I'm trying to generate a multipage TIFF file from an existing picture using code by Bob Powell:
picture.SelectActiveFrame(FrameDimension.Page, 0);
var image = new Bitmap(picture);
using (var stream = new MemoryStream())
{
ImageCodecInfo codecInfo = null;
foreach (var imageEncoder in ImageCodecInfo.GetImageEncoders())
{
if (imageEncoder.MimeType != "image/tiff") continue;
codecInfo = imageEncoder;
break;
}
var parameters = new EncoderParameters
{
Param = new []
{
new EncoderParameter(Encoder.SaveFlag, (long) EncoderValue.MultiFrame)
}
};
image.Save(stream, codecInfo, parameters);
parameters = new EncoderParameters
{
Param = new[]
{
new EncoderParameter(Encoder.SaveFlag, (long) EncoderValue.FrameDimensionPage)
}
};
for (var i = 1; i < picture.GetFrameCount(FrameDimension.Page); i++)
{
picture.SelectActiveFrame(FrameDimension.Page, i);
var img = new Bitmap(picture);
image.SaveAdd(img, parameters);
}
parameters = new EncoderParameters
{
Param = new[]
{
new EncoderParameter(Encoder.SaveFlag, (long)EncoderValue.Flush)
}
};
image.SaveAdd(parameters);
stream.Flush();
}
But it's not working (only the first frame is included in the image) and I don't know why.
What I want to do is to change a particular frame of a TIFF file (add annotations to it).
I don't know if there's a simpler way to do it but what I have in mind is to create a multipage TIFF from the original picture and add my own picture instead of that frame.
[deleted first part after comment]
I'm working with multi-page TIFFs using LibTIFF.NET; I found many quicks in handling of TIFF using the standard libraries (memory related and also consistent crashes on 16-bit gray scale images).
What is your test image? Have you tried a many-frame tiff (preferably with a large '1' on the first frame, a '2 on the next etc; this could help you to be certain on the frame included in the file.
Another useful diagnosis may be tiffdump utility, as included in LibTiff binaries (also for windows). This will tell you exactly what frames you have.
See Using LibTiff from c# to access tiled tiff images
[Edit] If you want to understand the .NET stuff: I've found a new resource on multi-page tiffs using the standard .NET functionality (although I'll stick with LibTIFF.NET): TheCodeProject : Save images into a multi-page TIFF file... If you download it, the code snippet in Form1.cs function saveMultipage(..) is similar (but still slightly different) than your code. Especially the flushing at the end is done in a differnt way, and the file is deleted before the first frame...
[/Edit]
It seems that this process doesn't change image object but it changes the stream so I should get the memory stream buffer and build another image object:
var buffer=stream.GetBuffer();
using(var newStream=new MemoryStream(buffer))
{
var result=Image.FromStream(newStream);
}
Now result will include all frames.

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