WriteableBitmapEx Discussions Rss Feed

New Post: Resizing Image distorts its pixels around corners

Tehreem — Sun, 19 May 2013 19:00:13 GMT

Hi!

I needed to resize an image so I used following code:

            WriteableBitmap img2 = new WriteableBitmap((int)width, (int)height);
            img2 = img.Resize((int)width, (int)height, WriteableBitmapExtensions.Interpolation.Bilinear);
destination.Blit(new Rect(coords.X, coords.Y, img2.PixelWidth, img2.PixelHeight), img2, new Rect(0,0, img2.PixelWidth, img2.PixelHeight));
            return destination;

But when i save this destination image it becomes distorted around the edges and gives me this image:

Any ideas for what can be wrong here?

New Post: Resize from byte array - What am I doing wrong here?

kevinfu — Tue, 14 May 2013 19:17:02 GMT

This worked for me!!!! Instead of ToByteArray or ToArray:

    public static byte[] ReadBytesFromStream(MemoryStream stream1)
    {
        MemoryStream stream = new MemoryStream(stream1.ToArray());
        byte[] size = new byte[16 * 1024];
        using (MemoryStream memoryStream = new MemoryStream())
        {
            int readCount;
            while ((readCount = stream.Read(size, 0, size.Length)) > 0)
            {
                memoryStream.Write(size, 0, readCount);
            }
            return memoryStream.ToArray();
        }
    }

New Post: Resize from byte array - What am I doing wrong here?

kevinfu — Tue, 14 May 2013 16:04:59 GMT

Now I am trying an encoder but when I save that image to SQL Server, it saves a purple splotchy image, even when I don't use resize.

However, I am still using ToByteArray (or ToArray) to save it to the database after encoding to JPEG. Is there something I can use instead to save the stream as a byte array into the database?

New Post: Resize from byte array - What am I doing wrong here?

teichgraf — Tue, 14 May 2013 15:20:10 GMT

The ToByteArray is a raw ARGB stream, so really big and can only be read via the FromByteArray method.
You should encode the image as JPEG, after the resize. Different platforms have different ways how to accomplish this.

New Post: Resize from byte array - What am I doing wrong here?

kevinfu — Tue, 14 May 2013 13:09:29 GMT

byte[] m_Bytes = ReadToEnd(fileStream); //converts fileStream to byte array - this works
WriteableBitmap bmp1 = new WriteableBitmap(166, 166);
bmp1.FromByteArray(m_Bytes);
WriteableBitmap resizedImage = bmp1.Resize(25, 25, WriteableBitmapExtensions.Interpolation.Bilinear);
byte[] buffer1 = resizedImage.ToByteArray(); //if I use bmp1 here, the code works fine
CurrentOrder.CompanyImage = buffer1; //saves an unreadable byte array in the DB

New Post: save PNG (transparent picture)

piyagr01 — Thu, 09 May 2013 01:23:11 GMT

Hi,

Can you please advise how I should use the code, such that when I save a png file on a windows 7 machine, I can open the png file in any image editor on the machine. Currently I can save silverlight writeablebitmap in a png file, and see the image in NT explorer but not in other applications.

New Post: Rendering ink strokes into canvas element of datatemplate in gridview

Vinay789 — Mon, 06 May 2013 10:39:37 GMT

Hi Experts,

I am trying to render the strokes into the canvas element of a datatemplate in gridview.

Can any one help me please?

Thanks in advance.

New Post: Error while reading IRandomAccessStream to Byte array

teichgraf — Tue, 23 Apr 2013 15:57:35 GMT

Use the FromStream method.
https://writeablebitmapex.codeplex.com/discussions/440934

New Post: WriteableBitmapExtensions is ambiguous in the namespace System.Windows.Media.Imaging

teichgraf — Tue, 23 Apr 2013 15:56:23 GMT

Can you please try one of the Blit samples you can download from the source code repo? They use BlendMode and it works.
https://writeablebitmapex.codeplex.com/SourceControl/BrowseLatest

New Post: WriteableBitmapExtensions is ambiguous in the namespace System.Windows.Media.Imaging

mafinthedales — Tue, 23 Apr 2013 15:13:31 GMT

New Post: Error while reading IRandomAccessStream to Byte array

Vinay789 — Tue, 23 Apr 2013 12:36:07 GMT

I am getting the following error while reading IRandomAccessStream to Byte Array

The operation attempted to access data outside the valid range.

Can any one help me please?

New Post: WriteableBitmapExtensions is ambiguous in the namespace System.Windows.Media.Imaging

mafinthedales — Tue, 23 Apr 2013 07:59:56 GMT

Tried that :(

New Post: WriteableBitmapExtensions is ambiguous in the namespace System.Windows.Media.Imaging

teichgraf — Mon, 22 Apr 2013 15:26:16 GMT

Try a full qualified name with the namespace for blend mode.

New Post: WriteableBitmapExtensions is ambiguous in the namespace System.Windows.Media.Imaging

mafinthedales — Mon, 22 Apr 2013 14:41:52 GMT

Hi.. Just started playing with your extensions but I get the error above when I add a blending mode to the Blit function.

If I search for it in object browser I see two WriteableBitmapExtensions listed. Is this what is causing the problem do you think?

Any ideas?

New Post: AccessViolationException when accessing pixel color (GetPixel())

Branyac — Sat, 20 Apr 2013 16:30:24 GMT

You're right, thank you. I changed the code and now it works well.

New Post: Simple image blitting/compositing with a background image and a foreground image.

Vinay789 — Sat, 20 Apr 2013 09:30:00 GMT

Hey guys,

I am waiting for your reply.

Please its urgent.!!!!:(

New Post: AccessViolationException when accessing pixel color (GetPixel())

teichgraf — Fri, 19 Apr 2013 18:29:39 GMT

You are using it wrong. The WinRT's SetSource will not load it right away, so when you access a pixel the buffer is not filled. Just check PixelWidth and PixelHeight

That's why WBX has the FromStrean extension method:

var tmpImage = await BitmapFactory.New(1, 1).FromStream(memoryStream);

Rene

New Post: AccessViolationException when accessing pixel color (GetPixel())

Branyac — Fri, 19 Apr 2013 16:02:12 GMT

Hi,

I'm using WriteableBitmapEx to edit an image taken with tablet's cam with Windows 8 Pro but I got an AccessViolationException every time I try to get a pixel color value, here's the code:

Windows.Media.Capture.MediaCapture captureMgr = new MediaCapture();
await captureMgr.InitializeAsync();

IRandomAccessStream memoryStream = new InMemoryRandomAccessStream();
await captureMgr.CapturePhotoToStreamAsync(imageProperties, memoryStream);
await memoryStream.FlushAsync();
memoryStream.Seek(0);

WriteableBitmap tmpImage = new WriteableBitmap(1, 1); 
tmpImage.SetSource(memoryStream);
tmpImage.GetPixel(1, 1); // An AccessViolationException occurs.

What I'm doing wrong? Or maybe a library bug?

New Post: Bliting two WriteableBitmap with WriteableBitmapEx

teichgraf — Thu, 18 Apr 2013 15:10:07 GMT

All WriteableBitmapEx algorithms rely on the Pbgra32 format, so all your bitmaps have to use that format.

New Post: Bliting two WriteableBitmap with WriteableBitmapEx

AdamAiken — Thu, 18 Apr 2013 14:22:52 GMT

Thank you Rene.

One more question.
Now I understand the problem. However, if I want to the output writeablebitmap as a Bgr32 one. Is there any way to convert _imageFrame to blit?
Adam