I am having trouble converting an image resource into byte[].
For example, I have the following resource:
pack://application:,,,/AppName;component/Assets/Images/sampleimage.jpg
in my program. How do I convert this into a byte[].
I've tried using a BitMapImage, but it's ImageSource ends up being null after initialised.
This seems to work:
var info = Application.GetResourceStream(uri);
var memoryStream = new MemoryStream();
info.Stream.CopyTo(memoryStream);
return memoryStream.ToArray();
A general solution to convert a BitmapSource into a byte[] would look like this:
public byte[] GetImageBuffer(BitmapSource bitmap, BitmapEncoder encoder)
{
encoder.Frames.Add(BitmapFrame.Create(bitmap));
using (var stream = new MemoryStream())
{
encoder.Save(stream);
return stream.ToArray();
}
}
You would use it like shown below, with any of the BitmapEncoders that are available in WPF.
var uri = new Uri("pack://application:,,,/AppName;component/Assets/Images/sampleimage.jpg");
var bitmap = new BitmapImage(uri);
var buffer = GetImageBuffer(bitmap, new JpegBitmapEncoder());
Related
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;
}
}
The Goal:
I want to convert an ImageBrush to a byte[].
Why?:
Because I want to print out the image, but I can't create any UI elements besides something like a MessageBox. SO I found an online tool that takes in a byte array and produces an image.
How do I do this in C# (WPF)?
What I've tried so far:
I have already converted the ImageBrush to a BitmapSource as so:
BitmapSource src = (BitmapSource)imageBrush.ImageSource;
and have converted the BitmapSource to a Bitmap Image as so:
private BitmapImage BitmapSourceToBitmapImage(BitmapSource bmpSrc)
{
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
MemoryStream memoryStream = new MemoryStream();
BitmapImage bImg = new BitmapImage();
encoder.Frames.Add(BitmapFrame.Create(bmpSrc));
encoder.Save(memoryStream);
memoryStream.Position = 0;
bImg.BeginInit();
bImg.StreamSource = memoryStream;
bImg.EndInit();
memoryStream.Close();
return bImg;
}
But for the life of me I cannot get this BitmapImage to a byte array! I have tried this:
private byte[] BitmapImagetoByteArray(BitmapImage bitmapImage) {
byte[] data;
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(bitmapImage));
using(MemoryStream ms = new MemoryStream())
{
encoder.Save(ms);
data = ms.ToArray();
}
return data;
}
The Problem/Error:
But when the encoder tries to save the memory stream, it says a frame has been disposed... see error message below:
Void SaveFrame(System.Windows.Media.SafeMILHandle, System.Windows.Media.SafeMILHandle, System.Windows.Media.Imaging.BitmapFrame)
Cannot access a disposed object.
System.ObjectDisposedException: Cannot access a disposed object.
at System.Windows.Media.Imaging.BitmapEncoder.SaveFrame(SafeMILHandle frameEncodeHandle, SafeMILHandle encoderOptions, BitmapFrame frame)
at System.Windows.Media.Imaging.BitmapEncoder.Save(Stream stream)
Any help? How can I display the ImageBrush without creating UI elements!
The error was not to set BitmapCacheOption.OnLoad, which is necessary when the source stream is to be closed right after EndInit:
bImg.BeginInit();
bImg.CacheOption = BitmapCacheOption.OnLoad;
bImg.StreamSource = memoryStream;
bImg.EndInit();
memoryStream.Close();
However, creating the intermediate BitmapImage wasn't necessary at all. The code should simply look like this:
private byte[] BitmapSourceToByteArray(BitmapSource bmpSrc)
{
var encoder = new JpegBitmapEncoder();
encoder.QualityLevel = 100;
encoder.Frames.Add(BitmapFrame.Create(bmpSrc));
using (var stream = new MemoryStream())
{
encoder.Save(stream);
return stream.ToArray();
}
}
I have this code, it works very well in android studio but not in xamarin
bitmap.Compress() has different arguments in xamarin and i am confused how to convert image into base64 or binary in xamarin.android?
I am receving an error in the 3rd line:
( bitmap.Compress() has some invalid arguments).
Bitmap bitmap = BitmapFactory.DecodeResource(Resources, Resource.Drawable.ace1);
ByteArrayOutputStream bao = new ByteArrayOutputStream();
bitmap.Compress(Bitmap.CompressFormat.Jpeg, 100,bao);
byte[] ba = bao.ToByteArray();
string bal = Base64.EncodeToString(ba, Base64.Default);
If you look at the documentation for Bitmap.Compress in Xamarin, you'll see that the last parameter is a Stream.
The equivalent of ByteArrayOutputStream in .NET is MemoryStream, so your code would be:
Bitmap bitmap = BitmapFactory.DecodeResource(Resources, Resource.Drawable.ace1);
MemoryStream stream = new MemoryStream();
bitmap.Compress(Bitmap.CompressFormat.Jpeg, 100, stream);
byte[] ba = stream.ToArray();
string bal = Base64.EncodeToString(ba, Base64Flags.Default);
(You could use Convert.ToBase64String instead of Base64.EncodeToString if you wanted, too.)
This is how I'm getting a Byte[] for my Bitmap object:
Byte[] imageArray = null;
Bitmap selectedProfilePic = this.GetProfilePicBitmap ();
if (selectedProfilePic != null) {
using (var ms = new System.IO.MemoryStream ()) {
selectedProfilePic.Compress (Bitmap.CompressFormat.Png, 0, ms);
imageArray = ms.ToArray ();
}
}
Hope this helps.
I have problem with converting BitmapImage to byte[]. I tried a lot of solutions and nothing works, every time i get different errors.
For example i found nice solutions but it also doesn't work. What's wrong with it?
I'm using Windows Phone 8.1.
public static byte[] ImageToBytes(BitmapImage img)
{
using (MemoryStream ms = new MemoryStream())
{
WriteableBitmap btmMap = new WriteableBitmap(img);
System.Windows.Media.Imaging.Extensions.SaveJpeg(btmMap, ms, img.PixelWidth, img.PixelHeight, 0, 100);
img = null;
return ms.ToArray();
}
}
this was taken from here: Convert Bitmap Image to byte array (Windows phone 8)
There is no argument given that corresponds to the required formal
parameter 'pixelHeight' of 'WriteableBitmap.WriteableBitmap(int, int)'
The type or namespace name 'Extensions' does not exist in the
namespace 'System.Windows.Media.Imaging' (are you missing an assembly
reference?)
or if somebody has got another idea how to convert it, please post it. Thanks a lot for any help!
I also tried this: BitmapImage to byte[]
but there was problem with usings
'BitmapImage' is an ambiguous reference between 'System.Windows.Media.Imaging.BitmapImage' and 'Windows.UI.Xaml.Media.Imaging.BitmapImage'
so I used "BitmapEncoder" but it doesn't have method like Save and Frame.
I think that it can't be done on this platform. I change my project to Windows Phone Silverlight/8.0 and there is working everything.
public static BitmapImage BytesToImage(byte[] bytes)
{
BitmapImage bitmapImage = new BitmapImage();
try
{
using (MemoryStream ms = new MemoryStream(bytes))
{
bitmapImage.SetSource(ms);
return bitmapImage;
}
}
finally { bitmapImage = null; }
}
public static byte[] ImageToBytes(BitmapImage img)
{
using (MemoryStream ms = new MemoryStream())
{
WriteableBitmap btmMap = new WriteableBitmap(img);
System.Windows.Media.Imaging.Extensions.SaveJpeg(btmMap, ms, img.PixelWidth, img.PixelHeight, 0, 100);
img = null;
return ms.ToArray();
}
}
see the below link it might help
https://social.msdn.microsoft.com/Forums/en-US/713c0ed1-d979-43ef-8857-bbe0b35576a9/windows-8-how-to-convert-bitmapimage-into-byte?forum=winappswithcsharp
Have you tried
MemoryStream ms = new MemoryStream();
WriteableBitmap wb = new WriteableBitmap(myImage);
wb.SaveJpeg(ms, myImage.PixelWidth, myImage.PixelHeight, 0, 100);
byte[] imageBytes = ms.ToArray();
You can also use extension method here
public static class MyExtensions
{
public static Byte[] ByteFromImage(this System.Windows.Media.Imaging.BitmapImage imageSource)
{
Stream stream = imageSource.StreamSource;
Byte[] imagebyte = null;
if (stream != null && stream.Length > 0)
{
using (BinaryReader br = new BinaryReader(stream))
{
imagebyte = br.ReadBytes((Int32)stream.Length);
}
}
return imagebyte;
}
}
and then call
System.Windows.Media.Imaging.BitmapImage myImage = new System.Windows.Media.Imaging.BitmapImage();
byte[] imageBytes = myImage.ByteFromImage();
If you're going to do any transformation on the image, you'll want to use the appropriate image encoder, then do something like below. If you're working with a multi-frame image (eg TIF), you need to add the frames one at a time to the encoder or you'll only get the first frame of the image.
MemoryStream ms = null;
TiffBitmapEncoder enc = null
enc = new TiffBitmapEncoder();
enc.Compression = TiffCompressOption.Ccitt4;
enc.Frames.Add(BitmapFrame.Create(bmpImg));
using (ms = new MemoryStream())
{
enc.Save(ms);
}
return ms.ToArray();
I need to convert System.Windows.Controls.Image to byte[].
How to do it ?
Assuming that you answer my query above that you are actually trying to convert an image into a byte array rather than an image control into a byte array here is the code to do so;
public byte[] imageToByteArray(System.Drawing.Image imageIn)
{
MemoryStream ms = new MemoryStream();
imageIn.Save(ms,System.Drawing.Imaging.ImageFormat.Gif);
return ms.ToArray();
}
In general, to convert an object to a byte array, you may want to use binary serialization. This will generate a memory stream from which you can extract a byte array.
You may start with this Question and Answer
System.Windows.Controls.Image img = new System.Windows.Controls.Image();
var uri = new Uri("pack://application:,,,/Images/myImage.jpg");
img.Source = new BitmapImage(uri);
byte[] arr;
using (MemoryStream ms = new MemoryStream())
{
var bmp = img.Source as BitmapImage;
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(bmp));
encoder.Save(ms);
arr = ms.ToArray();
}