how to convert byte[] into BitmapFrame c# - c#

I have tryed this but have exception - Operation is not valide due to current state of the object
private BitmapFrame backconvertor(byte[] incomingBuffer)
{
BitmapImage bmpImage = new BitmapImage();
MemoryStream mystream = new MemoryStream(incomingBuffer);
bmpImage.StreamSource = mystream;
BitmapFrame bf = BitmapFrame.Create(bmpImage);
return bf;
}
Error rising when I am trying to
return backconvertor(buff);
in other function (buff - is ready!)

Documentation indicates that in order to initialize the image, you need to do it between BeginInit and EndInit. That is:
bmpImage.BeginInit();
bmpImage.StreamSource = mystream;
bmpImage.EndInit();
Or, you can pass the stream to the constructor:
bmpImage = new BitmapImage(mystream);
See http://msdn.microsoft.com/en-us/library/system.windows.media.imaging.bitmapimage.begininit.aspx for an example and more discussion of BeginInit.

This is what I have in a WPF Converter to handle byte to BitmapFrame and it works perfectly:
var imgBytes = value as byte[];
if (imgBytes == null)
return null;
using (var stream = new MemoryStream(imgBytes))
{
return BitmapFrame.Create(stream,
BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
}
Also its thread safe as I have used it in Task.Run before also.

Related

Converting ImageSource to String on C# WPF

ESRI Symbology library is slow and sometimes take longer time than expected.
I wish to serialize a selected range of ImageSource to a cache, string in the memory or file.
I have searched the web but not much on ImageSource.
An interesting thing I have found is "ImageSourceValueSerializer".
Being a 3 months old baby in WPF, I am not so sure how to go about this.
here's how I got the ImageSource:
MultilayerPointSymbol multiLayerSym = await result.GetSymbolAsync() as MultilayerPointSymbol;
RuntimeImage swatch = await multiLayerSym.CreateSwatchAsync();
ImageSource symbolImage = await swatch.ToImageSourceAsync();
Tested Clemen's, the routine:
MultilayerPointSymbol multiLayerSym = await result.GetSymbolAsync() as MultilayerPointSymbol;
RuntimeImage swatch = await multiLayerSym.CreateSwatchAsync();
ImageSource symbolImage = await swatch.ToImageSourceAsync();
byte[] b = ImageSourceBinary(symbolImage);
ImageSource test = BinaryImageSource(b);
In the class:
private byte[] ImageSourceBinary(ImageSource imageSrc)
{
if (imageSrc is BitmapSource bitmapSource)
{
PngBitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(bitmapSource));
using (MemoryStream stream = new MemoryStream())
{
encoder.Save(stream);
return stream.ToArray();
}
}
return null;
}
private ImageSource BinaryImageSource(byte[] bytes)
{
using (MemoryStream stream = new MemoryStream(bytes))
{
PngBitmapDecoder decoder = new PngBitmapDecoder(stream, BitmapCreateOptions.IgnoreImageCache, BitmapCacheOption.Default);
BitmapFrame bf = decoder.Frames[0];
if (bf is ImageSource imagesource)
return imagesource;
return null;
}
}
The outcome, no image! :(
Check if the ImageSource is a BitmapSource and encode the BitmapSource by one of the BitmapEncoders. Encode into a MemoryStream or a FileStream.
private byte[] ImageSourceToByteArray(ImageSource imageSrc)
{
if (symbolImage is BitmapSource bitmapSource)
{
var encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(bitmapSource));
using (var stream = new MemoryStream())
{
encoder.Save(stream);
return stream.ToArray();
}
}
return null;
}
In order to decode an image from a byte array, do not explictly use a specific BitmapDecoder. Better rely on automatic decoder selection, like shown below. It is also important to set BitmapCacheOption.OnLoad when the stream is closed right after decoding.
private ImageSource ByteArrayToImageSource(byte[] bytes)
{
using (var stream = new MemoryStream(bytes))
{
return BitmapFrame.Create(
stream, BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
}
}

How to override(use) BitmapFrame.Thumbnail property in WPF C#?

Hello! The problem is? that I've got a multipage Tiff file to show, and I use
BitmapFrame.Thumbnail property to show small size thumbnail of every frame(page) of my multipage Tiff file. But< for some reason? the property returns null. Please, give step by step description, of how this should be done?
I've already tried to create my own BitmapSource thumbnail with this method:
public static BitmapImage GetThumbnail(BitmapFrame bitmapFrame)
{
try
{
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
MemoryStream memorystream = new MemoryStream();
BitmapImage tmpImage = new BitmapImage();
encoder.Frames.Add(bitmapFrame);
encoder.Save(memorystream);
tmpImage.BeginInit();
tmpImage.CacheOption = BitmapCacheOption.OnLoad;
tmpImage.StreamSource = new MemoryStream(memorystream.ToArray());
File.WriteAllBytes( $"{Path.GetTempFileName()}.jpg", memorystream.ToArray());
tmpImage.UriSource = new Uri($"{Path.GetTempFileName()}.jpg");
tmpImage.DecodePixelWidth = 80;
tmpImage.DecodePixelHeight = 120;
tmpImage.EndInit();
memorystream.Close();
return tmpImage;
}
catch (Exception ex)
{
return null;
throw ex;
}
}
then I convert the result to BitmapSource and create a list of BitmapFrames using:
List<BitmapFrame> tiffImageList = new List<BitmapFrame>();
tiffImageList.Add(new TiffImage() { index = imageIndex, image = BitmapFrame.Create(frame, (BitmapSource)GetThumbnail(frame))});
In the end I try to get property, but it returns null:
foreach (var tiffImage in tiffImageList)
{
Image image = new Image();
image.Source = tiffImage.image.Thumbnail;
}
I ran into a similar issue, modifying with the SDK PhotoViewerDemo example. Some valid jpg's are shown as white square thumbnails.
I think I found why the question code does not work. Ivan's question provides a correct constructor of BitmapFrame, but the functions have to create a BitmapSource, not a BitmapImage.
C# BitmapFrame.Thumbnail property is null for some images
I got it working with the function provided in that topic, using Ivan's call to the constructor, using the two bitmapsource arguments.
Code in the SDK example I now use is..
private BitmapSource CreateBitmapSource(Uri path)
{
BitmapImage bmpImage = new BitmapImage();
bmpImage.BeginInit();
bmpImage.UriSource = path;
bmpImage.EndInit();
return bmpImage;
}
private BitmapSource CreateThumbnail(Uri path)
{
BitmapImage bmpImage = new BitmapImage();
bmpImage.BeginInit();
bmpImage.UriSource = path;
bmpImage.DecodePixelWidth = 120;
bmpImage.EndInit();
return bmpImage;
}
// it has to be plugged in here,
public Photo(string path)
{
Source = path;
_source = new Uri(path);
// replaced.. Image = BitmapFrame.Create(_source);
// with this:
Image = BitmapFrame.Create(CreateBitmapSource(_source),CreateThumbnail(_source));
Metadata = new ExifMetadata(_source);
}

How can I decode a byte array using a JpegBitmapDecoder

I cannot decode images back from their encoded form as a (Jpeg) byte array retrieved from my database to be used as image sources for my WPF application.
The code I am using to encode them as a Jpeg byte array is as follows:
public byte[] bytesFromBitmap(BitmapImage bit)
{
byte[] data;
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(bit));
using (MemoryStream ms = new MemoryStream())
{
encoder.Save(ms);
data = ms.ToArray();
}
return data;
}
This is taking my Image taken directly from a webpage and assigned to an Image control like so:
var img = new BitmapImage(new Uri(entity.Image.ImageSrc)); //the entity has been saved in my DB, having been parsed from html
pbImage.Source = img;
This works just fine, I encode the BitmapImage and it saves just fine. But when I retrieve it from the DB and try to display it in another window, I cannot get it to work after trying every example I can see online - all either render nothing, or a black box or a visual mess not at all similar to the image I encoded.
Neither of the following have worked for me:
public BitmapSource GetBMImage(byte[] data)
{
using (var ms = new MemoryStream(data))
{
JpegBitmapDecoder decoder = new JpegBitmapDecoder(ms, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
BitmapSource frame = decoder.Frames[0];
return frame;
}
}
public static BitmapImage ImageFromBytes(byte[] imageData)
{
if (imageData == null)
{
return null;
}
else
{
var image = new BitmapImage();
using (var mem = new MemoryStream())
{
mem.Position = 0;
image.BeginInit();
image.CreateOptions = BitmapCreateOptions.PreservePixelFormat;
image.CacheOption = BitmapCacheOption.OnLoad;
image.UriSource = null;
image.StreamSource = mem;
image.EndInit();
}
image.Freeze();
return image;
}
} //this throws a 'No imaging component suitable to complete this operation was found' exception
Among other uses of memory streams and decoders I just can't get this to work - can anyone help?

Convert bitmap to ImageSource give NullReference exception

I've got WCF service to send image as a stream to client app.
My client app gets the stream :
Stream imageStream = client.GetImage();
When I use this code:
imageStream.CopyTo(stream);
int size = (int)stream.Length;
stream.Seek(0, SeekOrigin.Begin);
BitmapFrame bf = BitmapFrame.Create(stream,
BitmapCreateOptions.None,
BitmapCacheOption.OnLoad);
cam_img.Source = bf;
It work's fine but I need apply some filters to image before assign to source.
So I need bitmap. First, I convert Stream imageStream to byte array and then I use some code I find on forums:
byte[] tab_img;
using (var memoryStream = new MemoryStream())
{
imageStream.CopyTo(memoryStream);
tab_img= memoryStream.ToArray();
}
Bitmap bm;
using (MemoryStream mStream = new MemoryStream())
{
mStream.Write (tab_img, 0, tab_img.Length);
mStream.Seek(0, SeekOrigin.Begin);
bm = new Bitmap(mStream);
Grayscale filter = new Grayscale(0.2125, 0.7154, 0.0721);
Bitmap bm_post = filter.Apply(bm);
ImageSourceConverter c = new ImageSourceConverter();
object source = new ImageSourceConverter().ConvertFrom(bm_post);
ImageSource is1 = (ImageSource)source;
cam_img.Source = is1;
}
but I still get NullReferenceException in line
object source = new ImageSourceConverter().ConvertFrom(bm_post);

Converting image to base64

I have the following code to convert image to base64:
private void btnSave_Click(object sender, RoutedEventArgs e)
{
StreamResourceInfo sri = null;
Uri uri = new Uri("Checked.png", UriKind.Relative);
sri = Application.GetResourceStream(uri);
BitmapImage bitmap = new BitmapImage();
bitmap.SetSource(sri.Stream);
WriteableBitmap wb = new WriteableBitmap(bitmap);
MemoryStream ms = new MemoryStream();
wb.SaveJpeg(ms, bitmap.PixelWidth, bitmap.PixelHeight, 0, 100);
byte[] imageBytes = ms.ToArray();
base64 = System.Convert.ToBase64String(imageBytes);
}
And the following code to get Bitmap image form base 64:
public static BitmapImage base64image(string base64string)
{
byte[] fileBytes = Convert.FromBase64String(base64string);
using (MemoryStream ms = new MemoryStream(fileBytes, 0, fileBytes.Length))
{
ms.Write(fileBytes, 0, fileBytes.Length);
BitmapImage bitmapImage = new BitmapImage();
bitmapImage.SetSource(ms);
return bitmapImage;
}
}
So when i convert and deconvert it is blank.
I know that deconverter works, because, when i give him exact string:
string base64="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";
Which is my Checked.png converted in online converter. It decompreses perfectly.
And this is my base64, which i get by converting:
"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"
My problem is that string which i get as base64 from my code - is incorrect *What i did wrong?*
What about trying:
public static BitmapImage base64image(string base64string)
{
byte[] fileBytes = Convert.FromBase64String(base64string);
using (MemoryStream ms = new MemoryStream(fileBytes))
{
Image streamImage = Image.FromStream(ms);
context.Response.ContentType = "image/jpeg";
streamImage.Save(context.Response.OutputStream, ImageFormat.Jpeg);
return streamImage;
}
}
I agree with Alexei that your code for reading the image in does look a little strange. I've recently written some code for a similar task that I was doing which might point you in the right direction:
string fileContent = null;
/* Check the file actually has some content to display to the user */
if (uploadFile != null && uploadFile.ContentLength > 0)
{
byte[] fileBytes = new byte[uploadFile.ContentLength];
int byteCount = uploadFile.InputStream.Read(fileBytes, 0, (int)uploadFile.ContentLength);
if (byteCount > 0)
{
fileContent = CreateBase64Image(fileBytes);
}
}
private string CreateBase64Image(byte[] fileBytes)
{
Image streamImage;
/* Ensure we've streamed the document out correctly before we commit to the conversion */
using (MemoryStream ms = new MemoryStream(fileBytes))
{
/* Create a new image, saved as a scaled version of the original */
streamImage = ScaleImage(Image.FromStream(ms));
}
using (MemoryStream ms = new MemoryStream())
{
/* Convert this image back to a base64 string */
streamImage.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
return Convert.ToBase64String(ms.ToArray());
}
}
not an answer: more of a long comment ... OP states that decoding code works perfectly fine, also it looks suspicios. Also code assumed to be verified to work on PNG images, but saving code explicitly produces valid JPG with SaveJpeg call...
Your code that creates stream for reading looks strange - you create stream over existing byte array, than write the same bytes into that stream, and that pass that stream without seeking back to 0 to some method.
Potential fix (assuming BitampImage can accept JPG stream):
don't call Write at all as stream already have the bytes you want
set ms.Position = 0 after writing to the stream.
Note: I'm not sure if it is OK to dispose stream that is a source for BitmapImage, you may need to remove using too.

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