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Convert a JPG or PNG to WebP in C# .NET 6 [duplicate]

I'm writing a telegram bot that takes jpg from it's users and sends it back as stickers.
I did this correctly by downloading jpg, change the extension of file to png and upload and send it back as a sticker message to the user. as shown below:
var file = await bot.GetFileAsync(update.Message.Photo.LastOrDefault()?.FileId);
var filename = file.FileId + "." + file.FilePath.Split('.').Last();
var pngFileName = filename.Split('.')[0] + ".png";
using (var saveImageStream = System.IO.File.Open(pngFileName, FileMode.Create))
{
await bot.DownloadFileAsync(file.FilePath, saveImageStream);
await bot.SendTextMessageAsync(update.Message.Chat.Id, "please wait...");
}
using (var stream = System.IO.File.Open(pngFileName, FileMode.Open))
{
await bot.SendStickerAsync(update.Message.Chat.Id, stream);
}
but the these stickers don't load in telegram on IOS devices and this code just works for telegram users on android. I tried to just changing the extension of jpg file to webp but it didn't work.
after that I downloaded the standard telegram stickers and found that the standard format of stickers in telegram is webp files.
now I want to know how can I convert received jpg file to webp file.
I searched alot and just find this , found here .
using (Image image = Image.FromFile("image.jpg"))
{
Bitmap bitmap = new Bitmap(image);
WebPFormat.SaveToFile("image.webp", bitmap);
}
I added it's files to my project and I added "using LibwebpSharp;" at the top of my code, but when I add it's sample code, the VS cannot find "WebpFormat" class.
please help me and answer my question:
"How can I convert jpg to webp in C# telegram bot?"
thank you

I solved this problem in this way:
I installed Imazen.WebP nuget.
I downloaded the 32bit dll from here and added it to release folder.
I added "using Imazen.WebP;in top of my code
I used this code to convert jpg to webp.
var file = await bot.GetFileAsync(update.Message.Photo.LastOrDefault()?.FileId);
var jpgFileName = file.FileId + ".jpg";
using (var saveImageStream = System.IO.File.Open(jpgFileName,FileMode.Create))
{
await bot.DownloadFileAsync(file.FilePath, saveImageStream);
await bot.SendTextMessageAsync(update.Message.Chat.Id, "please wait...");
}
var webpFileName = file.FileId + ".webp";
using (Bitmap bitmap = new Bitmap(jpgFileName))
{
using (var saveImageStream = System.IO.File.Open(webpFileName, FileMode.Create))
{
var encoder = new SimpleEncoder();
encoder.Encode(bitmap, saveImageStream, 20);
}
}
using (var stream = System.IO.File.Open(webpFileName, FileMode.Open))
{
await bot.SendStickerAsync(update.Message.Chat.Id, stream);
}
System.IO.File.Delete(jpgFileName);
System.IO.File.Delete(webpFileName);

Install the following packages first using Visual Studio's NuGet package manager:
Install-Package System.Drawing.Common
Install-Package ImageProcessor
Install-Package ImageProcessor.Plugins.WebP
Then use this code for conversion:
using (var webPFileStream = new FileStream(WebpFilePath, FileMode.Create))
{
using (ImageFactory imageFactory = new ImageFactory(preserveExifData: false))
{
imageFactory.Load(File.OpenRead(OriginalImagePath))
.Format(new WebPFormat())
.Quality(100)
.Save(webPFileStream);
}
}

Imageprocessor looks like a good library to convert the image. There is a Webp plugin.
Here is an article that may help.
Code example:
using ImageProcessor;
using ImageProcessor.Plugins.WebP.Imaging.Formats;
using (var normalFileStream = new FileStream(normalImagePath, FileMode.Create))
using (var webPFileStream = new FileStream(webPImagePath, FileMode.Create))
using (var imageFactory = new ImageFactory(preserveExifData: false))
{
imageFactory.Load(image.OpenReadStream())
.Format(new WebPFormat())
.Quality(50)
.Save(webPFileStream);
}

How do I read and write XMP metadata in C#?

I have this method for resizing images, and I have managed to input all of the metadata into the new image except for the XMP data. Now, I can only find topics on how manage the XMP part in C++ but I need it in C#. The closest I've gotten is the xmp-sharp project which is based on some old port of Adobe's SDK, but I can't get that working for me. The MetaDataExtractor project gives me the same results - that is, file format/encoding not supported. I've tried this with .jpg, .png and .tif files.
Is there no good way of reading and writing XMP in C#?
Here is my code if it's of any help (omitting all irrelevant parts):
public Task<Stream> Resize(Size size, Stream image)
{
using (var bitmap = Image.FromStream(image))
{
var newSize = new Size(size.Width, size.Height);
var ms = new MemoryStream();
using (var bmPhoto = new Bitmap(newSize.Width, newSize.Height, PixelFormat.Format24bppRgb))
{
// This saves all metadata except XMP
foreach (var id in bitmap.PropertyIdList)
bmPhoto.SetPropertyItem(bitmap.GetPropertyItem(id));
// Trying to use xmp-sharp for the XMP part
try
{
IXmpMeta xmp = XmpMetaFactory.Parse(image);
}
catch (XmpException e)
{
// Here, I always get "Unsupported Encoding, XML parsing failure"
}
// Trying to use MetadataExtractor for the XMP part
try
{
var xmpDirs = ImageMetadataReader.ReadMetadata(image).Where(d => d.Name == "XMP");
}
catch (Exception e)
{
// Here, I always get "File format is not supported"
}
// more code to modify image and save to stream
}
ms.Position = 0;
return Task.FromResult<Stream>(ms);
}
}

The reason you get "File format is not supported" is because you already consumed the image from the stream when you called Image.FromStream(image) in the first few lines.
If you don't do that, you should find that you can read out the XMP just fine.
var xmp = ImageMetadataReader.ReadMetadata(stream).OfType<XmpDirectory().FirstOrDefault();
If your stream is seekable, you might be able to seek back to the origin (using the Seek method, or by setting Position to zero.)

PDF to bmp Images (12 pages = 12 images)

I have to deconstruct/extract a pdf page by page into bitmap images. This will be done on a server via a web service which I've setup. How do I get this right? It has to be page by page (1 page per image).
I am really stuck and I know one of you geniuses have the answer that I've been looking for.
I have tried: http://www.pdfsharp.net/wiki/ExportImages-sample.ashx Which didn't work correctly.
I am using C#;
The PDF is not password protected;
If this solution could take a Uri as a parameter for the location of the PDF it would be excellent!
The solution should not be reliant on Acrobat PDF Reader at all
I have been struggling for a very long time trying to use MigraDoc and PDFSharp and their alternatives to achieve the aforementioned problem.
ANY help/advice/code would be greatly appreciated!!
Thanks in advance!

LibPdf
This library converts converts PDF file to an image. Supported image formats are PNG and BMP, but you can easily add more.
Usage example:
using (FileStream file = File.OpenRead(#"..\path\to\pdf\file.pdf")) // in file
{
var bytes = new byte[file.Length];
file.Read(bytes, 0, bytes.Length);
using (var pdf = new LibPdf(bytes))
{
byte[] pngBytes = pdf.GetImage(0,ImageType.BMP); // image type
using (var outFile = File.Create(#"..\path\to\pdf\file.bmp")) // out file
{
outFile.Write(pngBytes, 0, pngBytes.Length);
}
}
}
Or Bytescout PDF Renderer SDK
using System;
using Bytescout.PDFRenderer;
namespace PDF2BMP
{
class Program
{
static void Main(string[] args)
{
// Create an instance of Bytescout.PDFRenderer.RasterRenderer object and register it.
RasterRenderer renderer = new RasterRenderer();
renderer.RegistrationName = "demo";
renderer.RegistrationKey = "demo";
// Load PDF document.
renderer.LoadDocumentFromFile("multipage.pdf");
for (int i = 0; i < renderer.GetPageCount(); i++)
{
// Render first page of the document to BMP image file.
renderer.RenderPageToFile(i, RasterOutputFormat.BMP, "image" + i + ".bmp");
}
// Open the first output file in default image viewer.
System.Diagnostics.Process.Start("image0.bmp");
}
}
}

put generated pdf file without saving it on the server

I have code (in a .ashx-file) that generates a PDF file from a PDF template. The generated pdf gets personalized with a name and a code. I use iTextSharp to do so.
This is the code:
using (var existingFileStream = new FileStream(fileNameExisting, FileMode.Open))
using (var newFileStream = new FileStream(fileNameNew, FileMode.Create))
{
var pdfReader = new PdfReader(existingFileStream);
var stamper = new PdfStamper(pdfReader, newFileStream);
var form = stamper.AcroFields;
var fieldKeys = form.Fields.Keys;
form.SetField("Name", name);
form.SetField("Code", code);
stamper.FormFlattening = true;
stamper.Close();
pdfReader.Close();
}
context.Response.AppendHeader("content-disposition", "inline; filename=zenith_coupon.pdf");
context.Response.TransmitFile(fileNameNew);
context.Response.ContentType = "application/pdf";
This works, but it saves the file on the server. I don't want to do that because there're going to be a lot of people downloading the PDF file and the server will be full in no time.
So my question is, how can I generate a PDF with iTextSharp without saving it and put it to the user?

Instead of using a FileStream you could use a MemoryStream and then use Response.Write() to output the stream contents.

You can use any Stream (for example MemoryStream) for the intermediate PDF (in your code currently named newFileStream) if you don't want to save it as a file - for sample code see http://www.developerfusion.com/code/6623/dynamically-generating-pdfs-in-net/ and http://forums.asp.net/t/1093198.aspx/1.
Just remember to rewind (i.e. set Position = 0) the MemoryStream before transmitting it to the client (for example by Response.Write or CopyTo (Response.OutputStream) )...

Loading Canon .CR2 files in .NET

I am trying to process Canon RAW .CR2 files using C#. My code is as follows:
BitmapDecoder bmpDec = BitmapDecoder.Create(new Uri(origFile), BitmapCreateOptions.DelayCreation, BitmapCacheOption.None);
BitmapEncoder bmpEnc = new BmpBitmapEncoder();
bmpEnc.Frames.Add(bmpDec.Frames[0]);
Stream ms = new MemoryStream();
bmpEnc.Save(ms);
Image srcImage = Bitmap.FromStream(ms);
The first few lines seem to run without a hitch, but the line
bmEnc.Save(ms);
just hangs without completing and without raising any exception.
Has anyone had any success with this?

Know this is a old thread but I found a nice easy to use library (Magick.NET).
How to do a conversion:
using (MagickImage image = new MagickImage("StillLife.CR2"))
{
image.Write("StillLife.jpg");
}
https://github.com/dlemstra/Magick.NET/blob/master/docs/ReadRawImageFromCamera.md
Details of nuget package installation:
Install-Package Magick.NET-Q16-AnyCPU
https://github.com/dlemstra/Magick.NET

W8.1 or W7 after applying https://www.microsoft.com/en-us/download/details.aspx?id=26829 seems to work well
var files = Directory.GetFiles(#"D:\DCIM","*.CR2");
for(var i = 0; i < files.Length; i++) {
Console.Write("{0,-4}: {1} => ", i, files[i]);
var bmpDec = BitmapDecoder.Create(new Uri(files[i]), BitmapCreateOptions.DelayCreation, BitmapCacheOption.None);
var bmpEnc = new JpegBitmapEncoder();
bmpEnc.QualityLevel = 100;
bmpEnc.Frames.Add(bmpDec.Frames[0]);
var oldfn = Path.GetFileName(files[i]);
var newfn = Path.ChangeExtension(oldfn, "JPG");
using(var ms = File.Create(Path.Combine(#"D:\DCIM\100CANON", newfn), 10000000)) {
bmpEnc.Save(ms);
}
Console.WriteLine(newfn);
}

I don't believe BitmapDecoder understands .CR2. It is not a conventional image format by far, as it contains the raw bayer-sensor image (one color per pixel), not a standard image.
If you want to convert CR2 and other camera raw formats, you should look at DCRaw: http://www.cybercom.net/~dcoffin/dcraw/ or libraw (based on dcraw, friendly as a library): http://www.libraw.org/