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How to create image handler from pdf with pdflibnet?

i used PDFLIBNET to convert pdf to image :
public void ConvertPDFtoPNG(string filename, String dirOut)
{
try
{
PDFLibNet.PDFWrapper _pdfDoc = new PDFLibNet.PDFWrapper();
_pdfDoc.LoadPDF(filename);
System.Drawing.Image img = RenderPage(_pdfDoc, 0);
img.Save(Path.Combine(dirOut, Path.GetFileNameWithoutExtension(filename) + ".png"));
_pdfDoc.Dispose();
return;
}
catch
{
File.Copy(System.IO.Path.Combine(Environment.CurrentDirectory, "0.png"), Path.GetFileNameWithoutExtension(filename) + ".png");
}
}
This code is working properly
But i need to use in image handler without saving image
I change this code to use MemoryStream but get gray image :
public string ConvertPDFtoPNG(string filename)
{
PDFLibNet.PDFWrapper _pdfDoc = new PDFLibNet.PDFWrapper();
_pdfDoc.LoadPDF(filename);
System.Drawing.Image img = RenderPage(_pdfDoc, 0);
MemoryStream ms = new MemoryStream();
img.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
_pdfDoc.Dispose();
base64String = Convert.ToBase64String(ms.ToArray(), 0, ms.ToArray().Length);
}
please help me
thanks

Try this:
var b = File.ReadAllBytes(filename);
using (var ms = new MemoryStream(b))
{
var i = Image.FromStream(ms);
i.Save(ms, ImageFormat.Jpeg);
}

How can i clear the memory after converting BitmapImage to Byte

I have two functions: one to convert from image to byte and other to convert from byte to bitmapImage.
So, when I open the window with that images, I convert from byte to bitmapImage and it works great, but when I close and open it again it just keeps on memory and if I continue to do that time and time again it just throws an exception Out Of Memory exception
Image to byte->
private byte[] ConvertImageToBinary(Image img)
{
using (MemoryStream ss = new MemoryStream())
{
img.Save(ss, System.Drawing.Imaging.ImageFormat.Jpeg);
var s = ss.ToArray();
var jpegQuality = 50;
Image image;
using (var inputStream = new MemoryStream(s))
{
image = Image.FromStream(inputStream);
var jpegEncoder = System.Drawing.Imaging.ImageCodecInfo.GetImageDecoders()
.First(c => c.FormatID == System.Drawing.Imaging.ImageFormat.Jpeg.Guid);
var encoderParameters = new System.Drawing.Imaging.EncoderParameters(1);
encoderParameters.Param[0] = new System.Drawing.Imaging.EncoderParameter(System.Drawing.Imaging.Encoder.Quality, jpegQuality);
Byte[] outputBytes;
using (var outputStream = new MemoryStream())
{
image.Save(outputStream, jpegEncoder, encoderParameters);
return outputBytes = outputStream.ToArray();
}
}
}
}
Byte to bitmap ->
public BitmapImage ConvertBinaryToImage(byte[] array)
{
var image = new BitmapImage();
using (var ms = new MemoryStream(array))
{
image.BeginInit();
image.CacheOption = BitmapCacheOption.OnLoad; // here
image.StreamSource = ms;
image.EndInit();
image.Freeze();
}
return image;
}
When I open the WindowDragAndDrop it loads all the images
But when I close it it still uses the same amount of memory

Image is indeed disposable (https://learn.microsoft.com/en-us/dotnet/api/system.drawing.image?view=netframework-4.8), so you also need:
using (var image = Image.FromStream(inputStream)){
}
Around everywhere you use Image objects.

Bitmap from Memstream of an SVG gives invalid parameter exception

The last line of the following code gives the error "Parameter is not valid", when the original image is an SVG:
var imageBytes = Convert.FromBase64String(imageBase64String);
var memStream = new MemoryStream(imageBytes);
//memStream.Seek(0, SeekOrigin.Begin);
var imageObject = new Bitmap(memStream);
Help please. Thanks.
EDIT: The image for example I am using is the image of the first formula in the following page right under the Theoremsection:
https://en.wikipedia.org/wiki/Green%27s_theorem

Can you try with 'using' for memorystream to handle garbage collection by itself?
var imageBytes = Convert.FromBase64String(imageBase64String);
Bitmap m = ByteToBitmap(imageBytes);
public static Bitmap ByteToBitmap(byte[] imageByte)
{
using (MemoryStream mStream = new MemoryStream())
{
mStream.Write(imageByte, 0, imageByte.Length); // this will stream dataand handle image length by itself
mStream.Seek(0, SeekOrigin.Begin);
Bitmap bm = new Bitmap(mStream);
return bm;
}
}
For SVG,
public static Bitmap ByteToBitmap(byte[] imageByte)
{
using (MemoryStream mStream = new MemoryStream(imageByte))
{
var s= SvgDocument.Open(mStream);
var bm= svgDocument.Draw();
return bm;
}
}

How to convert .tff images to CCITT4 format

I got the new image successfully, but I can't get the original image, the image was cropped.
Here is the code I tried:
private byte[] ConvertToCCITT4(byte[] input)
{
MemoryStream memoryStream1 = new MemoryStream(input);
RasterCodecs.CodecsPath = new FileInfo(Assembly.GetExecutingAssembly().Location).DirectoryName;
RasterCodecs rasterCodecs = new RasterCodecs();
using (IRasterImage irasterImage = rasterCodecs.Load((Stream)memoryStream1))
{
MemoryStream memoryStream2 = new MemoryStream();
rasterCodecs.Save(irasterImage, (Stream)memoryStream2, (RasterImageFormat)29, 1);
return memoryStream2.ToArray();
}
}

C# Load JPG file, extract BitmapImage

I am trying to extract a BitmapImage from a JPG. This is the code I have:
FileStream fIn = new FileStream(sourceFileName, FileMode.Open); // source JPG
Bitmap dImg = new Bitmap(fIn);
MemoryStream ms = new MemoryStream();
dImg.Save(ms, ImageFormat.Jpeg);
image = new BitmapImage();
image.BeginInit();
image.StreamSource = new MemoryStream(ms.ToArray());
image.EndInit();
ms.Close();
image comes back with a 0 × 0 image, which of course means it didn't work. How do I do this?

Try this:
public void Load(string fileName)
{
using(Stream BitmapStream = System.IO.File.Open(fileName,System.IO.FileMode.Open ))
{
Image img = Image.FromStream(BitmapStream);
mBitmap=new Bitmap(img);
//...do whatever
}
}
Or you can just do this (source):
Bitmap myBmp = Bitmap.FromFile("path here");