Develop Reference

Conversion from byte[] to image using image.FromStream method

I try converting image data from the database which is already in byte[] back to the image and I'm getting "invalid parameter error" using Image.FileStream.
Please, can anyone help me out with this?
I've tried working around the code using various methods and the last one is below in my code.
byte[] data = validaccount.FingerPrint;
try
{
using (MemoryStream strm = new MemoryStream())
{
strm.Write(data, 0, data.Length);
strm.Position = 0;
System.Drawing.Image img = System.Drawing.Image.FromStream(strm);
BitmapImage bi = new BitmapImage();
bi.BeginInit();
MemoryStream ms = new MemoryStream();
img.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
ms.Seek(0, SeekOrigin.Begin);
bi.StreamSource = ms;
bi.EndInit();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
The code is supposed to convert the byte[] into an image.

According to the docs, Image.FromStream(stream) will throw an argument exception if "The stream does not have a valid image format". Have you verified the data is actually correct? If so, what type of image is it?
You're misusing your streams. You only need 1 memory stream and it has a constructor that takes a byte array (no need to write the bytes yourself). Be sure to wrap it in a using block (like you did for your first stream).
You may not want to use BitmapImage - that's for xaml/wpf apps. You probably want System.Drawing.Bitmap which inherits/extends System.Drawing.Image. Additionally, Bitmap has a constructor which takes a stream - no need to use FromStream.
Finally, Image (and hence Bitmap since Bitmap inherits Image) implements IDisposable, so you should also wrap it in a using block.
P.S. This is a duplicate question.

Though its not memory stream, this method has worked for me and if you browse SO for your question, some times MS does not work.
using System.Drawing;
var converterdImage = (Bitmap)((new ImageConverter()).ConvertFrom(byteArray));
Byte Array to Image Conversion

Convert a Bitmap to a Texture2D in Unity

I'm in a scenario where I'm manipulating bitmaps using AForge.net in Unity. However, a Bitmap can't be applied to a texture in Unity, so I visibly can see my output, so how is this done?
I believe I have to use the MemoryStream, but in what fashion is unknown to me.

I managed to achieve this by using a memorystream, i.e.:
MemoryStream msFinger = new MemoryStream();
bitmapCurrentframeRed.Save(msFinger, bitmapCurrentframeRed.RawFormat);
redCamera.LoadImage(msFinger.ToArray());
redFilter.GetComponent<Renderer>().material.mainTexture = redCamera;
With bitmapCurrentframeRed being a Bitmap,
redCamera being a texture2D and redFilter being a GameObject(plane) used to view my output.

you can try these line to convert System.Drawing.Bitmap to UnityEngine.Texture2D
Bitmap bmp = new Bitmap;
MemoryStream ms= new MemoryStream();
bmp.Save(ms,ImageFormat.PNG);
var buffer = new byte[ms.Length];
ms.position = 0;
ms.Read(buffer,0,buffer.Length);
Texture2D t = new Texture2D(1,1);
t.LoadImage(buffer);

I want to use a Texture2d as a system.drawing.bitmap

XNA.Texture2D to System.Drawing.Bitmap I am sure this answered my question but it linked an external site and is no longer available.
I am using a windows form in an xna game. I want to use a background image for one of my panels. It is easy enough to do the loading from file, but when the game is deployed to another system obviously the file location will be different.
Bitmap bmp = new Bitmap(#"c:\myImage.png");
In the above mentioned question, someone had suggested usign Texture2d.saveToPng then open the bitmap from the memory stream. This sounds great, if someone could steer me in that direction. Any other ideas?

This works for me. If there are problems with it please let me know.
public static Image Texture2Image(Texture2D texture)
{
Image img;
using (MemoryStream MS = new MemoryStream())
{
texture.SaveAsPng(MS, texture.Width, texture.Height);
//Go To the beginning of the stream.
MS.Seek(0, SeekOrigin.Begin);
//Create the image based on the stream.
img = Bitmap.FromStream(MS);
}
return img;
}

You can use two methods that allow you to create a Bitmap, use Texture2D.SaveAsJpeg() or Texture2D.SaveAsPng().
MemoryStream memoryStream = new MemoryStream();
Texture2D texture = Content.Load<Texture2D>( "Images\\test" );
texture.SaveAsJpeg( memoryStream, texture.Width, texture.Height ); //Or SaveAsPng( memoryStream, texture.Width, texture.Height )
System.Drawing.Bitmap bmp = new System.Drawing.Bitmap( memoryStream );

Difficulty Saving Image To MemoryStream

I'm having some difficulty saving a stream of bytes from an image (in this case, a jpg) to a System.IO.MemoryStream object. The goal is to save the System.Drawing.Image to a MemoryStream, and then use the MemoryStream to write the image to an array of bytes (I ultimately need to insert it into a database). However, inspecting the variable data after the MemoryStream is closed shows that all of the bytes are zero... I'm pretty stumped and not sure where I'm doing wrong...
using (Image image = Image.FromFile(filename))
{
byte[] data;
using (MemoryStream m = new MemoryStream())
{
image.Save(m, image.RawFormat);
data = new byte[m.Length];
m.Write(data, 0, data.Length);
}
// Inspecting data here shows the array to be filled with zeros...
}
Any insights will be much appreciated!

To load data from a stream into an array, you read, not write (and you would need to rewind). But, more simply in this case, ToArray():
using (MemoryStream m = new MemoryStream())
{
image.Save(m, image.RawFormat);
data = m.ToArray();
}

If the purpose is to save the image bytes to a database, you could simply do:
byte[] imgData = System.IO.File.ReadAllBytes(#"path/to/image.extension");
And then plug in your database logic to save the bytes.

I found for another reason this article some seconds ago, maybe you will find it useful:
http://www.codeproject.com/KB/recipes/ImageConverter.aspx
Basically I don't understand why you try to write an empty array over a memory stream that has an image. Is that your way to clean the image?
If that's not the case, read what you have written in your memorystream with ToArray method and assign it to your byte array
And that's all

Try this way, it works for me
MemoryStream ms = new MemoryStream();
Bitmap bmp = new Bitmap(panel1.Width, panel1.Height);
panel1.DrawToBitmap(bmp, panel1.Bounds);
bmp.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
byte[] Pic_arr = new byte[ms.Length];
ms.Position = 0;
ms.Read(Pic_arr, 0, Pic_arr.Length);
ms.Close();
Well instead of a Image control, I used a Panel Control.

Create Bitmap from Collection of BitmapSources

I would like to create the Bitmap from BitmapSource Collection and Each source source should be one frame.
I wrote the following code
MemoryStream memStream = new MemoryStream();
BitmapEncoder enCoder = new GifBitmapEncoder();
foreach (BitmapSource source in BitmapSources)
enCoder.Frames.Add(BitmapFrame.Create(source));
enCoder.Save(memStream);
_Bitmap = new DrawingCtrl.Bitmap(memStream);
DrawingCtrl.ImageAnimator.Animate(_Bitmap, OnFrameChanged);
and
private void OnFrameChangedInMainThread()
{
DrawingCtrl.ImageAnimator.UpdateFrames(_Bitmap);
Source = GetBitmapSource(_Bitmap);
InvalidateVisual();
}
But it shows "Exception has been thrown by the target of an invocation.". Could anyone help me?

I don’t know about BitmapSources in WPF, but I notice an error in how you use MemoryStream, so maybe this is the issue:
enCoder.Save(memStream);
This will write the content to the memory stream and leave the stream pointer at the end.
_Bitmap = new DrawingCtrl.Bitmap(memStream);
This will then try to read the bitmap from the stream, starting at the end of the stream. Of course that can’t work. Try adding a seek in between:
enCoder.Save(memStream);
memStream.Seek(0, SeekOrigin.Begin);
_Bitmap = new DrawingCtrl.Bitmap(memStream);