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Convert ByteArray into png image and add it to ImageView in Xamarin.Android

I have the Image ByteArray and want to convert the byte array into png image and add in ImageView as you see in the below code.
byte[] imageBytes = webClient.DownloadDataTaskAsync(uri);
ImageView view = new ImageView(this.Context);
//Here need to add the converted image into ImageView
view.SetImageSource();
I achieved this, by converting ImageBytes into a bitmap and add the bitmap in ImageView. But it has some memory problem. As I adding more no.of times frequently in my source, I couldn't use a bitmap to add in ImageView due to the memory exception.
So please help me.
Thanks.

You can do it by creating the bitmap from Stream to do that use this:
using(var ms = new MemoryStream(imageBytes))
{
var bitmap = BitmapFactory.DecodeStream(ms);
// ...
// rest of your logic here...
// ...
}
Hope this helps

It should be as easy as calling
var bitmap = BitmapFactory.DecodeByteArray(imageBytes, 0, imageBytes.Length);
Android.Graphics.BitmapFactory.DecodeByteArray Method
Decode an immutable bitmap from the specified byte array.
Parameters
data
byte array of compressed image data
offset
offset into imageData for where the decoder should begin parsing.
length
the number of bytes, beginning at offset, to parse
opts
null-ok; Options that control downsampling and whether the image should be completely decoded, or just is size returned.

C# byte[] to bitmap System.InvalidOperationException

I'm doing a C# web service soap receiving an image.
I send a string contain the byte characters.
I transform the string in byte[] and next I world like to create the Bitmap.
The line Bitmap img = new Bitmap(ms); generate an exception : invalid argument.
I have a in the ms object this error : System.InvalidOperationException
value contain the correct string, imgBytes contain the good number of sell.
public string GetImage(string value)
{
byte[] imgBytes = Encoding.ASCII.GetBytes(value);
MemoryStream ms = new MemoryStream(imgBytes, true);
Bitmap img = new Bitmap(ms);
Code with debug mode
Exception
Thank you for your help.

It looks like your string holds base64 encoded data. Try to decode it to a byte array via Convert.FromBase64String

I had a similar problem. Basically you write into your memory stream (in the constructor) and the position pointer is at the end. So before reuse the memory stream you can try setting its position pointer to the beginning. Like this:
MemoryStream ms = new MemoryStream(imgBytes, true);
ms.Position = 0;
Bitmap img = new Bitmap(ms);
or the more general approach:
MemoryStream ms = new MemoryStream(imgBytes, true);
ms.Seek(0, SeekOrigin.Begin);
Bitmap img = new Bitmap(ms);
Hope this will solve your Problem.
Update
I think #heinbeinz answer is also important: First decode your string from the right encoding (normally base64), then set the position.

Parameter is not valid while converting byte array to image

i have a database with an image filed.I have read this Image field and convert to byte array with code below.
imageByte = ((dtgrid.CurrentRow.Cells[2].Value) as System.Data.Linq.Binary).ToArray();
When I Create a stream and Assign it to PictureBox image like this:
MemoryStream ms = new MemoryStream(imageByte);
pictureBox1.Image = Image.FromStream(ms);
I have this error:
Parameter is not valid.
How Can I fix this.

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 .

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