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How to convert a base64 source to image source in xamarin

I want to convert a svg base64 string to image and need to assign that to image source in Xamarin How to implement the same . Please help on this.
Var dImage="data:image/avg+XML;base64,PD94b.....=="
My base64 string is in the above format.I did the normal base64 to image convertion but it didn't worked.

Can you please try it with plain data (without mime-type,...):
=> Convert.FromBase64String("PD94b.....==");
var dImage = "data:image/avg+XML;base64,PD94b.....==";
var base64 = dImage.Split(',')[1];
byte[] bytes = Convert.FromBase64String(base64);
Image image;
using (MemoryStream ms = new MemoryStream(bytes))
{
image = Image.FromStream(ms);
}

I want to save image in database

I have an image on a page, e.g <img id="img3" runat="server" src="image.jpg" width="200" height="200"/> and I'd like to save the image referenced by the src attribute in my database using stored procedure.
I should convert the image to binary first.
Here is what I have so far:
Stream fs = FileUpload1.PostedFile.InputStream;
BinaryReader br = new BinaryReader(fs);
Byte[] bytes = br.ReadBytes((Int32)fs.Length);
cmd.Parameters.AddWithValue("#img", byte);
But the thing is that I don't want to save the uploaded image FileUpload1.PostedFile.InputStream, I want to save the image that I had its src.
Is there a way to put the image src in stream so that I can save it or what is the right way for doing that?

Generally it is not recommended to store images in Database or any other type of files in RDBMS. What is most effective way, to store the file over disk on server, and store that path in your table.
So whenever you need to reference that image/file, then fetch the path from the database, and read the file from disk. This broadly has following two benefits.
Removes the extensive conversion process (from image to binary and
vice-versa).
Helps to read the image directly (soft-read).

Saving an image in the database is not recommanded, but if you insist on saving it in your database you can convert the image to base64, then save the base64 string in your database.
using (Image image = Image.FromStream(FileUpload1.PostedFile.InputStream))
{
using (MemoryStream m = new MemoryStream())
{
image.Save(m, image.RawFormat);
byte[] imageBytes = m.ToArray();
// Convert byte[] to Base64 String
string base64String = Convert.ToBase64String(imageBytes);
//Now save the base64String in your database
}
}
And to convert it back from base64 to an image:
public Image GetImageFromBase64String(string base64String)
{
byte[] bytes = Convert.FromBase64String(base64String);
Image image;
using (MemoryStream ms = new MemoryStream(bytes))
{
image = Image.FromStream(ms);
}
return image;
I combined some code from converting a base 64 string to an image and saving it
and from Convert image path to base64 string .

How to convert Image to base64 format without Losing of Image Quality?

I have implemented two Winform Application,One application for Image to base64 Conversion and another for base64 string to Image Conversion.First i converted image to base64 string format.
Output of above application is base64 string.
for e.g code is
public string ImageToBase64(Image image, System.Drawing.Imaging.ImageFormat format)
{
using (MemoryStream ms = new MemoryStream())
{
// Convert Image to byte[]
image.Save(ms, format);
byte[] imageBytes = ms.ToArray();
// Convert byte[] to Base64 String
string base64String = Convert.ToBase64String(imageBytes);
return base64String;
}
}
In my another application(base64 to Image conversion) i converted base64 string to image,the output of this application is image.
for e.g. code is
public Image Base64ToImage(string base64String)
{
// Convert Base64 String to byte[]
byte[] imageBytes = Convert.FromBase64String(base64String);
MemoryStream ms = new MemoryStream(imageBytes, 0, imageBytes.Length);
// Convert byte[] to Image
ms.Write(imageBytes, 0, imageBytes.Length);
Image image = Image.FromStream(ms, true);
return image;
}
The quality of this image is poor compare to previous image .how to resolve this?

The quality of this image is poor compare to previous image .how to resolve this?
Pass in an ImageFormat which doesn't lose quality, basically. This has nothing to do with the base64 encoding part - that's just a way of converting binary data to text and back. It's lossless.
To prove this to yourself, just save an image to a MemoryStream, rewind it and then load it from the stream - you'll see exactly the same loss of quality. Fix that, and the improvement will still be present when you use base64 to encode it as text.

Displaying image in ASP.NET C#

I am converting Base64 code to image and I am using following way to save and display that image.
var kpin = Base64ToImage(TextBox1.Text);
kpin.Save(#"e:\myim.png");
Image1.ImageUrl = #"e:\myim.png";
and class is
public Image Base64ToImage(string base64String)
{
byte[] imageBytes = Convert.FromBase64String(base64String);
MemoryStream ms = new MemoryStream(imageBytes, 0,
imageBytes.Length);
ms.Write(imageBytes, 0, imageBytes.Length);
Image image = Image.FromStream(ms, true);
return image;
}
and this process working fine but I need an image not to be saved in hard disk. How to display this image directly without saving to hard disk and retrieving back.

Instead of setting the Image1.ImageURL to the path of your image, you can instead do one of several things:
Use an img tag with the Base64 data in it directly - http://www.sweeting.org/mark/blog/2005/07/12/base64-encoded-images-embedded-in-html
Not all browsers support this.
Create an Action or Webform (depending on whether you're using ASP.NET MVC or not) that takes as input whatever you need to either retrieve or generate the Base64 encoded data, and then set the response headers to serve the correct content type (image/png or something) and write the image directly to the Response.OutputStream (or use ContentResult in ASP.NET MVC). Tons of examples via Stackoverflow on how to do either.
-M

Don't bother with the image object at all, and just do it direct:
public void Base64ToResponse(string base64String)
{
Response.ContentType = "text/png"; //or whatever...
byte[] imageBytes = Convert.FromBase64String(base64String);
Response.OutputStream(imageBytes, 0, imageBytes.Length);
}

C# - High Quality Byte Array Conversion of Images

I am converting images to byte array and storing in a text file using the following code. I am retrieving them successfully as well.
My concern is that the quality of the retrieved image is not up to the expectation. Is there a way to have better conversion to byte array and retrieving? I am not worried about the space conception.
Please share your thoughts.
string plaintextStoringLocation = #"D:\ImageSource\Cha5.txt";
string bmpSourceLocation = #"D:\ImageSource\Cha50.bmp";
////Read image
Image sourceImg = Image.FromFile(bmpSourceLocation);
////Convert to Byte[]
byte[] clearByteArray = ImageToByteArray(sourceImg);
////Store it for future use (in plain text form)
StoreToLocation(clearByteArray, plaintextStoringLocation);
//Read from binary
byte[] retirevedImageBytes = ReadByteArrayFromFile(plaintextStoringLocation);
//Retrieve from Byte[]
Image destinationImg = ByteArrayToImage(retirevedImageBytes);
//Display Image
pictureBox1.Image = destinationImg;
EDIT: And the solution is - use Base64
//Plain Text Storing Location
string plaintextStoringLocation = #"D:\ImageSource\GirlInflower23.txt";
string bmpSourceLocation = #"D:\ImageSource\GirlInflower1.bmp";
////Read image
Image sourceImg = Image.FromFile(bmpSourceLocation);
string base64StringOfIMage = ImageToBase64(sourceImg, ImageFormat.Bmp);
byte[] byteOfString = Convert.FromBase64String(base64StringOfIMage);
StoreToLocation(byteOfString, plaintextStoringLocation);
byte[] retrievedBytesForStrimngForImage = ReadByteArrayFromFile(plaintextStoringLocation);
MemoryStream memStream = new MemoryStream(retrievedBytesForStrimngForImage);
//memStream.Read();
Image retrievedImg = Image.FromStream(memStream);
pictureBox1.Image = retrievedImg;

Yes, it is possible to get completely lossless storage. If you just store it in its original BMP format there will be no problem. I assume you are converting it to text because you want to send it via some protocol where binary characters will be corrupted.
Instead of whatever you are doing, you could consider using Convert.ToBase64String.

I haven't had any problems with this fragment...try it...if you get good results then the problem is in your Image -> byte[] or byte[] -> Image code :)
Image srcImage;
Image destImage;
// load an image
srcImage = Image.FromFile(filename);
// save the image via stream -> byte[]
using(MemoryStream stream = new MemoryStream()){
image.Save(stream, ImageFormat.xxx);
byte[] saveArray = stream.ToArray();
/*..... strore saveArray......*/
}
// rehydrate
byte[] loadArray = /*...get byte array from storage...*/
using(MemoryStream stream = new MemeoryStream(loadArray)){
destImage = Image.FromStream(stream);
}
pictureBox.Image = dstImage;
// don't forget...dispose of any Image/Stream objects