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  • When constructing a Bitmap with Bitmap.FromHbitmap(), how soon can the original bitmap handle be del

    - by GBegen
    From the documentation of Image.FromHbitmap() at http://msdn.microsoft.com/en-us/library/k061we7x%28VS.80%29.aspx : The FromHbitmap method makes a copy of the GDI bitmap; so you can release the incoming GDI bitmap using the GDIDeleteObject method immediately after creating the new Image. This pretty explicitly states that the bitmap handle can be immediately deleted with DeleteObject as soon as the Bitmap instance is created. Looking at the implementation of Image.FromHbitmap() with Reflector, however, shows that it is a pretty thin wrapper around the GDI+ function, GdipCreateBitmapFromHBITMAP(). There is pretty scant documentation on the GDI+ flat functions, but http://msdn.microsoft.com/en-us/library/ms533971%28VS.85%29.aspx says that GdipCreateBitmapFromHBITMAP() corresponds to the Bitmap::Bitmap() constructor that takes an HBITMAP and an HPALETTE as parameters. The documentation for this version of the Bitmap::Bitmap() constructor at http://msdn.microsoft.com/en-us/library/ms536314%28VS.85%29.aspx has this to say: You are responsible for deleting the GDI bitmap and the GDI palette. However, you should not delete the GDI bitmap or the GDI palette until after the GDI+ Bitmap::Bitmap object is deleted or goes out of scope. Do not pass to the GDI+ Bitmap::Bitmap constructor a GDI bitmap or a GDI palette that is currently (or was previously) selected into a device context. Furthermore, one can see the source code for the C++ portion of GDI+ in GdiPlusBitmap.h that the Bitmap::Bitmap() constructor in question is itself a wrapper for the GdipCreateBitmapFromHBITMAP() function from the flat API: inline Bitmap::Bitmap( IN HBITMAP hbm, IN HPALETTE hpal ) { GpBitmap *bitmap = NULL; lastResult = DllExports::GdipCreateBitmapFromHBITMAP(hbm, hpal, &bitmap); SetNativeImage(bitmap); } What I can't easily see is the implementation of GdipCreateBitmapFromHBITMAP() that is the core of this functionality, but the two remarks in the documentation seem to be contradictory. The .Net documentation says I can delete the bitmap handle immediately, and the GDI+ documentation says the bitmap handle must be kept until the wrapping object is deleted, but both are based on the same GDI+ function. Furthermore, the GDI+ documentation warns against using a source HBITMAP that is currently or previously selected into a device context. While I can understand why the bitmap should not be selected into a device context currently, I do not understand why there is a warning against using a bitmap that was previously selected into a device context. That would seem to prevent use of GDI+ bitmaps that had been created in memory using standard GDI. So, in summary: Does the original bitmap handle need to be kept around until the .Net Bitmap object is disposed? Does the GDI+ function, GdipCreateBitmapFromHBITMAP(), make a copy of the source bitmap or merely hold onto the handle to the original? Why should I not use an HBITMAP that was previously selected into a device context?

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  • Bitmap to Texture2D problem with colors

    - by xnaNewbie89
    I have a small problem with converting a bitmap to a Texture2D. The resulted image of the conversion has the red channel switched with the blue channel :/ I don't know why, because the pixel formats are the same. If someone can help me I will be very happy :) System.Drawing.Image image = System.Drawing.Bitmap.FromFile(ImageFileLoader.filename); System.Drawing.Bitmap bitmap = new System.Drawing.Bitmap(image); Texture2D mapTexture = new Texture2D(Screen.Game.GraphicsDevice, bitmap.Width, bitmap.Height,false,SurfaceFormat.Color); System.Drawing.Imaging.BitmapData data = bitmap.LockBits(new System.Drawing.Rectangle( 0, 0, bitmap.Width, bitmap.Height), System.Drawing.Imaging.ImageLockMode.ReadOnly,System.Drawing.Imaging.PixelFormat.Format32bppArgb); byte[] bytes = new byte[data.Height * data.Width*4]; System.Runtime.InteropServices.Marshal.Copy(data.Scan0, bytes, 0, bytes.Length); mapTexture.SetData<byte>(bytes, 0, data.Height * data.Width * 4); bitmap.UnlockBits(data); bitmap.Dispose(); image.Dispose();

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  • Android Tile Bitmap

    - by Rich Lawrence
    I'm trying to load a bitmap in Android which I want to tile. I'm currently using the following in my view to display a bitmap: canvas.drawBitmap(bitmap, srcRect, destRect, null) I essentially want to use this bitmap as a background image in my app and would like to repeat the bitmap in both the X and Y directions. I've seen the TileMode.REPEAT constant for the BitmapShader class but am unsure if this is to do with repeating he actual bitmap or to do with applying a filter to the bitmap.

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  • Drawing a bitmap in a canvas after calling setBitmap doesn't work

    - by kodbar_k
    I'm drawing a bitmap in a canvas and i want to have the result in a new bitmap, but i still have a black screen as result. This is my code, part of the onDraw(Canvas canvas) method : if (bitmapTemplate == null) { canvasBis = new Canvas(); bitmapTemplate = Bitmap.createBitmap(canvas.getWidth()+30,canvas.getHeight(),Bitmap.Config.ARGB_8888); drawZones(canvasBis,bitmapTemplate); } bitmapRes = Bitmap.createBitmap(canvas.getWidth()+30,canvas.getHeight(),Bitmap.Config.ARGB_8888); canvas.setBitmap(bitmapRes); canvas.drawBitmap(bitmapTemplate, matrix, null); My goal is to have a new bitmap (bitmapRes) by applying a matrix on an existing bitmap (bitmapTemplate). With this code i alway have a black screen, but when i remove the line canvas.setBitmap(bitmapRes) i have a result but not in a new bitmap. any ideas please ? Maybe transparency ? Thanks in advance. drawZones draws some zones in bitmapTemplate.

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  • No transperancy in Bitmap loading from MemoryStream

    - by Jogi Joseph George
    Please see the C# code. When i am writing a Bitmap to a file and read from the file, i am getting the transperancy correctly. using (Bitmap bmp = new Bitmap(2, 2)) { Color col = Color.FromArgb(1, 2, 3, 4); bmp.SetPixel(0, 0, col); bmp.Save("J.bmp"); } using (Bitmap bmp = new Bitmap("J.bmp")) { Color col = bmp.GetPixel(0, 0); // ------------------------------ // Here col.A is 1. This is right. // ------------------------------ } But if I write the Bitmap to a MemoryStream and read from that MemoryStream, the transperancy has been removed. All Alpha values become 255. MemoryStream ms = new MemoryStream(); using (Bitmap bmp = new Bitmap(2, 2)) { Color col = Color.FromArgb(1, 2, 3, 4); bmp.SetPixel(0, 0, col); bmp.Save(ms, ImageFormat.Bmp); } using (Bitmap bmp = new Bitmap(ms)) { Color col = bmp.GetPixel(0, 0); // ------------------------------ // But here col.A is 255. Why? i am expecting 1 here. // ------------------------------ } I wish to save the Bitmap to a MemoryStream and read it back with transperancy. Could you please help me?

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  • WPF Blurry Images - Bitmap Class

    - by Luke
    I am using the following sample at http://blogs.msdn.com/dwayneneed/archive/2007/10/05/blurry-bitmaps.aspx within VB.NET. The code is shown below. I am having a problem when my application loads the CPU is pegging 50-70%. I have determined that the problem is with the Bitmap class. The OnLayoutUpdated() method is calling the InvalidateVisual() continously. This is because some points are not returning as equal but rather, Point(0.0,-0.5) Can anyone see any bugs within this code or know a better implmentation for pixel snapping a Bitmap image so it is not blurry? p.s. The sample code was in C#, however I believe that it was converted correctly. Imports System Imports System.Collections.Generic Imports System.Windows Imports System.Windows.Media Imports System.Windows.Media.Imaging Class Bitmap Inherits FrameworkElement ' Use FrameworkElement instead of UIElement so Data Binding works as expected Private _sourceDownloaded As EventHandler Private _sourceFailed As EventHandler(Of ExceptionEventArgs) Private _pixelOffset As Windows.Point Public Sub New() _sourceDownloaded = New EventHandler(AddressOf OnSourceDownloaded) _sourceFailed = New EventHandler(Of ExceptionEventArgs)(AddressOf OnSourceFailed) AddHandler LayoutUpdated, AddressOf OnLayoutUpdated End Sub Public Shared ReadOnly SourceProperty As DependencyProperty = DependencyProperty.Register("Source", GetType(BitmapSource), GetType(Bitmap), New FrameworkPropertyMetadata(Nothing, FrameworkPropertyMetadataOptions.AffectsRender Or FrameworkPropertyMetadataOptions.AffectsMeasure, New PropertyChangedCallback(AddressOf Bitmap.OnSourceChanged))) Public Property Source() As BitmapSource Get Return DirectCast(GetValue(SourceProperty), BitmapSource) End Get Set(ByVal value As BitmapSource) SetValue(SourceProperty, value) End Set End Property Public Shared Function FindParentWindow(ByVal child As DependencyObject) As Window Dim parent As DependencyObject = VisualTreeHelper.GetParent(child) 'Check if this is the end of the tree If parent Is Nothing Then Return Nothing End If Dim parentWindow As Window = TryCast(parent, Window) If parentWindow IsNot Nothing Then Return parentWindow Else ' Use recursion until it reaches a Window Return FindParentWindow(parent) End If End Function Public Event BitmapFailed As EventHandler(Of ExceptionEventArgs) ' Return our measure size to be the size needed to display the bitmap pixels. ' ' Use MeasureOverride instead of MeasureCore so Data Binding works as expected. ' Protected Overloads Overrides Function MeasureCore(ByVal availableSize As Size) As Size Protected Overloads Overrides Function MeasureOverride(ByVal availableSize As Size) As Size Dim measureSize As New Size() Dim bitmapSource As BitmapSource = Source If bitmapSource IsNot Nothing Then Dim ps As PresentationSource = PresentationSource.FromVisual(Me) If Me.VisualParent IsNot Nothing Then Dim window As Window = window.GetWindow(Me.VisualParent) If window IsNot Nothing Then ps = PresentationSource.FromVisual(window.GetWindow(Me.VisualParent)) ElseIf FindParentWindow(Me) IsNot Nothing Then ps = PresentationSource.FromVisual(FindParentWindow(Me)) End If End If ' If ps IsNot Nothing Then Dim fromDevice As Matrix = ps.CompositionTarget.TransformFromDevice Dim pixelSize As New Vector(bitmapSource.PixelWidth, bitmapSource.PixelHeight) Dim measureSizeV As Vector = fromDevice.Transform(pixelSize) measureSize = New Size(measureSizeV.X, measureSizeV.Y) Else measureSize = New Size(bitmapSource.PixelWidth, bitmapSource.PixelHeight) End If End If Return measureSize End Function Protected Overloads Overrides Sub OnRender(ByVal dc As DrawingContext) Dim bitmapSource As BitmapSource = Me.Source If bitmapSource IsNot Nothing Then _pixelOffset = GetPixelOffset() ' Render the bitmap offset by the needed amount to align to pixels. dc.DrawImage(bitmapSource, New Rect(_pixelOffset, DesiredSize)) End If End Sub Private Shared Sub OnSourceChanged(ByVal d As DependencyObject, ByVal e As DependencyPropertyChangedEventArgs) Dim bitmap As Bitmap = DirectCast(d, Bitmap) Dim oldValue As BitmapSource = DirectCast(e.OldValue, BitmapSource) Dim newValue As BitmapSource = DirectCast(e.NewValue, BitmapSource) If ((oldValue IsNot Nothing) AndAlso (bitmap._sourceDownloaded IsNot Nothing)) AndAlso (Not oldValue.IsFrozen AndAlso (TypeOf oldValue Is BitmapSource)) Then RemoveHandler DirectCast(oldValue, BitmapSource).DownloadCompleted, bitmap._sourceDownloaded RemoveHandler DirectCast(oldValue, BitmapSource).DownloadFailed, bitmap._sourceFailed ' ((BitmapSource)newValue).DecodeFailed -= bitmap._sourceFailed; // 3.5 End If If ((newValue IsNot Nothing) AndAlso (TypeOf newValue Is BitmapSource)) AndAlso Not newValue.IsFrozen Then AddHandler DirectCast(newValue, BitmapSource).DownloadCompleted, bitmap._sourceDownloaded AddHandler DirectCast(newValue, BitmapSource).DownloadFailed, bitmap._sourceFailed ' ((BitmapSource)newValue).DecodeFailed += bitmap._sourceFailed; // 3.5 End If End Sub Private Sub OnSourceDownloaded(ByVal sender As Object, ByVal e As EventArgs) InvalidateMeasure() InvalidateVisual() End Sub Private Sub OnSourceFailed(ByVal sender As Object, ByVal e As ExceptionEventArgs) Source = Nothing ' setting a local value seems scetchy... RaiseEvent BitmapFailed(Me, e) End Sub Private Sub OnLayoutUpdated(ByVal sender As Object, ByVal e As EventArgs) ' This event just means that layout happened somewhere. However, this is ' what we need since layout anywhere could affect our pixel positioning. Dim pixelOffset As Windows.Point = GetPixelOffset() If Not AreClose(pixelOffset, _pixelOffset) Then InvalidateVisual() End If End Sub ' Gets the matrix that will convert a Windows.Point from "above" the ' coordinate space of a visual into the the coordinate space ' "below" the visual. Private Function GetVisualTransform(ByVal v As Visual) As Matrix If v IsNot Nothing Then Dim m As Matrix = Matrix.Identity Dim transform As Transform = VisualTreeHelper.GetTransform(v) If transform IsNot Nothing Then Dim cm As Matrix = transform.Value m = Matrix.Multiply(m, cm) End If Dim offset As Vector = VisualTreeHelper.GetOffset(v) m.Translate(offset.X, offset.Y) Return m End If Return Matrix.Identity End Function Private Function TryApplyVisualTransform(ByVal Point As Windows.Point, ByVal v As Visual, ByVal inverse As Boolean, ByVal throwOnError As Boolean, ByRef success As Boolean) As Windows.Point success = True If v IsNot Nothing Then Dim visualTransform As Matrix = GetVisualTransform(v) If inverse Then If Not throwOnError AndAlso Not visualTransform.HasInverse Then success = False Return New Windows.Point(0, 0) End If visualTransform.Invert() End If Point = visualTransform.Transform(Point) End If Return Point End Function Private Function ApplyVisualTransform(ByVal Point As Windows.Point, ByVal v As Visual, ByVal inverse As Boolean) As Windows.Point Dim success As Boolean = True Return TryApplyVisualTransform(Point, v, inverse, True, success) End Function Private Function GetPixelOffset() As Windows.Point Dim pixelOffset As New Windows.Point() Dim ps As PresentationSource = PresentationSource.FromVisual(Me) If ps IsNot Nothing Then Dim rootVisual As Visual = ps.RootVisual ' Transform (0,0) from this element up to pixels. pixelOffset = Me.TransformToAncestor(rootVisual).Transform(pixelOffset) pixelOffset = ApplyVisualTransform(pixelOffset, rootVisual, False) pixelOffset = ps.CompositionTarget.TransformToDevice.Transform(pixelOffset) ' Round the origin to the nearest whole pixel. pixelOffset.X = Math.Round(pixelOffset.X) pixelOffset.Y = Math.Round(pixelOffset.Y) ' Transform the whole-pixel back to this element. pixelOffset = ps.CompositionTarget.TransformFromDevice.Transform(pixelOffset) pixelOffset = ApplyVisualTransform(pixelOffset, rootVisual, True) pixelOffset = rootVisual.TransformToDescendant(Me).Transform(pixelOffset) End If Return pixelOffset End Function Private Function AreClose(ByVal Point1 As Windows.Point, ByVal Point2 As Windows.Point) As Boolean Return AreClose(Point1.X, Point2.X) AndAlso AreClose(Point1.Y, Point2.Y) End Function Private Function AreClose(ByVal value1 As Double, ByVal value2 As Double) As Boolean If value1 = value2 Then Return True End If Dim delta As Double = value1 - value2 Return ((delta < 0.00000153) AndAlso (delta > -0.00000153)) End Function End Class

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  • How to update off screen bitmap in a surfaceview thread

    - by DKDiveDude
    I have a Surfaceview thread and an off canvas texture bitmap that is being generated (changed), first row (line), every frame and then copied one position (line) down on regular surfaceview bitmap to make a scrolling effect, and I then continue to draw other things on top of that. Well that is what I really want, however I can't get it to work even though I am creating a separate canvas for off screen bitmap. It is just not scrolling at all. I other words I have a memory bitmap, same size as Surfaceview canvas, which I need to scroll (shift) down one line every frame, and then replace top line with new random texture, and then draw that on regular Surfaceview canvas. Here is what I thought would work; My surfaceChanged where I specify bitmap and canvasses and start thread: @Override public void surfaceCreated(SurfaceHolder holder) { intSurfaceWidth = mSurfaceView.getWidth(); intSurfaceHeight = mSurfaceView.getHeight(); memBitmap = Bitmap.createBitmap(intSurfaceWidth, intSurfaceHeight, Bitmap.Config.ARGB_8888); memCanvas = new Canvas(memCanvas); myThread = new MyThread(holder, this); myThread.setRunning(true); blnPause = false; myThread.start(); } My thread, only showing essential middle running part: @Override public void run() { while (running) { c = null; try { // Lock canvas for drawing c = myHolder.lockCanvas(null); synchronized (mSurfaceHolder) { // First draw off screen bitmap to off screen canvas one line down memCanvas.drawBitmap(memBitmap, 0, 1, null); // Create random one line(row) texture bitmap memTexture = Bitmap.createBitmap(imgTexture, 0, rnd.nextInt(intTextureImageHeight), intSurfaceWidth, 1); // Now add this texture bitmap to top of off screen canvas and hopefully bitmap memCanvas.drawBitmap(textureBitmap, intSurfaceWidth, 0, null); // Draw above updated off screen bitmap to regular canvas, at least I thought it would update (save changes) shifting down and add the texture line to off screen bitmap the off screen canvas was pointing to. c.drawBitmap(memBitmap, 0, 0, null); // Other drawing to canvas comes here } finally { // do this in a finally so that if an exception is thrown // during the above, we don't leave the Surface in an // inconsistent state if (c != null) { myHolder.unlockCanvasAndPost(c); } } } } For my game Tunnel Run. Right now I have a working solution where I instead have an array of bitmaps, size of surface height, that I populate with my random texture and then shift down in a loop for each frame. I get 50 frames per second, but I think I can do better by instead scrolling bitmap.

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  • Android Bitmap.createBitmap returns negative mHeight

    - by Hai Bi
    Modifying the Snake example. An exception was created from the bitmap class. So I debug the original Snake, and found that in TileView there is a function loadTile, Bitmap bitmap = Bitmap.createBitmap(mTileSize, mTileSize, Bitmap.Config.ARGB_8888); after the above assignment, the bitmap had -1 for mHeight and mWidth. Then how does the Snake even work? I am just use the Eclipse and the virtual machine, not a real android phone.

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  • Rotation of bitmap using a frame by frame animation

    - by pengume
    Hey every one I know this has probably been asked a ton of times but I just wanted to clarify if I am approaching this correctly, since I ran into some problems rotating a bitmap. So basically I have one large bitmap that has four frames drawn on it and I only draw one at a time by looping through the bitmap by increments to animate walking. I can get the bitmap to rotate correctly when it is not moving but once the animation starts it starts to cut off alot of the image and sometimes becomes very fuzzy. I have tried public void draw(Canvas canvas,int pointerX, int pointerY) { Matrix m; if (setRotation){ // canvas.save(); m = new Matrix(); m.reset(); // spriteWidth and spriteHeight are for just the current frame showed m.setTranslate(spriteWidth / 2, spriteHeight / 2); //get and set rotation for ninja based off of joystick m.preRotate((float) GameControls.getRotation()); //create the rotated bitmap flipedSprite = Bitmap.createBitmap(bitmap , 0, 0,bitmap.getWidth(),bitmap.getHeight() , m, true); //set new bitmap to rotated ninja setBitmap(flipedSprite); // canvas.restore(); Log.d("Ninja View", "angle of rotation= " +(float) GameControls.getRotation()); setRotation = false; } And then the Draw Method here // create the destination rectangle for the ninjas current animation frame // pointerX and pointerY are from the joystick moving the ninja around destRect = new Rect(pointerX, pointerY, pointerX + spriteWidth, pointerY + spriteHeight); canvas.drawBitmap(bitmap, getSourceRect(), destRect, null); The animation is four frames long and gets incremented by 66 (the size of one of the frames on the bitmap) for every frame and then back to 0 at the end of the loop.

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  • Use native HBitmap in C# while preserving alpha channel/transparency. Please check this code, it works on my computer...

    - by David
    Let's say I get a HBITMAP object/handle from a native Windows function. I can convert it to a managed bitmap using Bitmap.FromHbitmap(nativeHBitmap), but if the native image has transparency information (alpha channel), it is lost by this conversion. There are a few questions on Stack Overflow regarding this issue. Using information from the first answer of this question (How to draw ARGB bitmap using GDI+?), I wrote a piece of code that I've tried and it works. It basically gets the native HBitmap width, height and the pointer to the location of the pixel data using GetObject and the BITMAP structure, and then calls the managed Bitmap constructor: Bitmap managedBitmap = new Bitmap(bitmapStruct.bmWidth, bitmapStruct.bmHeight, bitmapStruct.bmWidth * 4, PixelFormat.Format32bppArgb, bitmapStruct.bmBits); As I understand (please correct me if I'm wrong), this does not copy the actual pixel data from the native HBitmap to the managed bitmap, it simply points the managed bitmap to the pixel data from the native HBitmap. And I don't draw the bitmap here on another Graphics (DC) or on another bitmap, to avoid unnecessary memory copying, especially for large bitmaps. I can simply assign this bitmap to a PictureBox control or the the Form BackgroundImage property. And it works, the bitmap is displayed correctly, using transparency. When I no longer use the bitmap, I make sure the BackgroundImage property is no longer pointing to the bitmap, and I dispose both the managed bitmap and the native HBitmap. The Question: Can you tell me if this reasoning and code seems correct. I hope I will not get some unexpected behaviors or errors. And I hope I'm freeing all the memory and objects correctly. private void Example() { IntPtr nativeHBitmap = IntPtr.Zero; /* Get the native HBitmap object from a Windows function here */ // Create the BITMAP structure and get info from our nativeHBitmap NativeMethods.BITMAP bitmapStruct = new NativeMethods.BITMAP(); NativeMethods.GetObjectBitmap(nativeHBitmap, Marshal.SizeOf(bitmapStruct), ref bitmapStruct); // Create the managed bitmap using the pointer to the pixel data of the native HBitmap Bitmap managedBitmap = new Bitmap( bitmapStruct.bmWidth, bitmapStruct.bmHeight, bitmapStruct.bmWidth * 4, PixelFormat.Format32bppArgb, bitmapStruct.bmBits); // Show the bitmap this.BackgroundImage = managedBitmap; /* Run the program, use the image */ MessageBox.Show("running..."); // When the image is no longer needed, dispose both the managed Bitmap object and the native HBitmap this.BackgroundImage = null; managedBitmap.Dispose(); NativeMethods.DeleteObject(nativeHBitmap); } internal static class NativeMethods { [StructLayout(LayoutKind.Sequential)] public struct BITMAP { public int bmType; public int bmWidth; public int bmHeight; public int bmWidthBytes; public ushort bmPlanes; public ushort bmBitsPixel; public IntPtr bmBits; } [DllImport("gdi32", CharSet = CharSet.Auto, EntryPoint = "GetObject")] public static extern int GetObjectBitmap(IntPtr hObject, int nCount, ref BITMAP lpObject); [DllImport("gdi32.dll")] internal static extern bool DeleteObject(IntPtr hObject); }

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  • Auto scrolling or shifting a bitmap in .NET

    - by mikej
    I have a .NET GDI+ bitmap object (or if it makes the problem easier a WPF bitmap object) and what I want to to is shift the whole lot by dx,dy (whole pixels) and I would ideally like to do it using .NET but API calls are ok. It has to be efficient bacause its going to be called 10,000 times say with moderately large bitmaps. I have implemented a solution using DrawImage - but its slow and it halts the application for minutes while the GC cleans up the temp objects that have been used. I have also started to work on a version using ScrollDC but so far have had no luck getting it to work on the DC of the bitmap (I can make it work buy creating an API bitmap with bitmap handle, then creating a compatible DC asnd calling ScrollDC but then I have to put it back into the bitmap object). There has to be an "inplace" way of shifting a bitmap. mikej

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  • How to convert ISampleGrabber::BufferCB's buffer to a bitmap

    - by user2509919
    I am trying to use the ISampleGrabberCB::BufferCB to convert the current frame to bitmap using the following code: int ISampleGrabberCB.BufferCB(double sampleTime, IntPtr buffer, int bufferLength) { try { Form1 form1 = new Form1("", "", ""); if (pictureReady == null) { Debug.Assert(bufferLength == Math.Abs(pitch) * videoHeight, "Wrong Buffer Length"); } Debug.Assert(imageBuffer != IntPtr.Zero, "Remove Buffer"); Bitmap bitmapOfCurrentFrame = new Bitmap(width, height, capturePitch, PixelFormat.Format24bppRgb, buffer); MessageBox.Show("Works"); form1.changepicturebox3(bitmapOfCurrentFrame); pictureReady.Set(); } catch (Exception ex) { MessageBox.Show(ex.ToString()); } return 0; } However this does not seem to be working. Additionally it seems to call this function when i press a button which runs the following code: public IntPtr getFrame() { int hr; try { pictureReady.Reset(); } catch (Exception ex) { MessageBox.Show(ex.ToString()); } imageBuffer = Marshal.AllocCoTaskMem(Math.Abs(pitch) * videoHeight); try { gotFrame = true; if (videoControl != null) { hr = videoControl.SetMode(stillPin, VideoControlFlags.Trigger); DsError.ThrowExceptionForHR(hr); } if (!pictureReady.WaitOne(9000, false)) { throw new Exception("Timeout waiting to get picture"); } } catch { Marshal.FreeCoTaskMem(imageBuffer); imageBuffer = IntPtr.Zero; } return imageBuffer; } Once this code is ran I get a message box which shows 'Works' thus meaning my BufferCB must of been called however does not update my picture box with the current image. Is the BufferCB not called after every new frame? If so why do I not recieve the 'Works' message box? Finally is it possible to convert every new frame into a bitmap (this is used for later processing) using BufferCB and if so how? Edited code: int ISampleGrabberCB.BufferCB(double sampleTime, IntPtr buffer, int bufferLength) { Debug.Assert(bufferLength == Math.Abs(pitch) * videoHeight, "Wrong Buffer Length"); Debug.Assert(imageBuffer != IntPtr.Zero, "Remove Buffer"); CopyMemory(imageBuffer, buffer, bufferLength); Decode(buffer); return 0; } public Image Decode(IntPtr imageData) { var bitmap = new Bitmap(width, height, pitch, PixelFormat.Format24bppRgb, imageBuffer); bitmap.RotateFlip(RotateFlipType.RotateNoneFlipY); Form1 form1 = new Form1("", "", ""); form1.changepicturebox3(bitmap); bitmap.Save("C:\\Users\\...\\Desktop\\A2 Project\\barcode.jpg"); return bitmap; } Button code: public void getFrameFromWebcam() { if (iPtr != IntPtr.Zero) { Marshal.FreeCoTaskMem(iPtr); iPtr = IntPtr.Zero; } //Get Image iPtr = sampleGrabberCallBack.getFrame(); Bitmap bitmapOfFrame = new Bitmap(sampleGrabberCallBack.width, sampleGrabberCallBack.height, sampleGrabberCallBack.capturePitch, PixelFormat.Format24bppRgb, iPtr); bitmapOfFrame.RotateFlip(RotateFlipType.RotateNoneFlipY); barcodeReader(bitmapOfFrame); } public IntPtr getFrame() { int hr; try { pictureReady.Reset(); } catch (Exception ex) { MessageBox.Show(ex.ToString()); } imageBuffer = Marshal.AllocCoTaskMem(Math.Abs(pitch) * videoHeight); try { gotFrame = true; if (videoControl != null) { hr = videoControl.SetMode(stillPin, VideoControlFlags.Trigger); DsError.ThrowExceptionForHR(hr); } if (!pictureReady.WaitOne(9000, false)) { throw new Exception("Timeout waiting to get picture"); } } catch { Marshal.FreeCoTaskMem(imageBuffer); imageBuffer = IntPtr.Zero; } return imageBuffer; } I also still need to press the button to run the BufferCB Thanks for reading.

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  • How to update a user created Bitmap in the Windows API

    - by gamernb
    In my code I quickly generate images on the fly, and I want to display them as quickly as possible. So the first time I create my image, I create a new BITMAP, but instead of deleting the old one and creating a new one for every subsequent image, I just want to copy my data back into the existing one. Here is my code to do both the initial creation and the updating. The creation works just fine, but the updating one doesn't work. BITMAPINFO bi; HBITMAP Frame::CreateBitmap(HWND hwnd, int tol1, int tol2, bool useWhite, bool useBackground) { ZeroMemory(&bi.bmiHeader, sizeof(BITMAPINFOHEADER)); bi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER); bi.bmiHeader.biWidth = width; bi.bmiHeader.biHeight = height; bi.bmiHeader.biPlanes = 1; bi.bmiHeader.biBitCount = 24; bi.bmiHeader.biCompression = BI_RGB; ZeroMemory(bi.bmiColors, sizeof(RGBQUAD)); // Allocate memory for bitmap bits int size = height * width; Pixel* newPixels = new Pixel[size]; // Recompute the output //memcpy(newPixels, pixels, size*3); ComputeOutput(newPixels, tol1, tol2, useWhite, useBackground); HBITMAP bitmap = CreateDIBitmap(GetDC(hwnd), &bi.bmiHeader, CBM_INIT, newPixels, &bi, DIB_RGB_COLORS); delete newPixels; return bitmap; } and void Frame::UpdateBitmap(HWND hwnd, HBITMAP bitmap, int tol1, int tol2, bool useWhite, bool useBackground) { ZeroMemory(&bi.bmiHeader, sizeof(BITMAPINFOHEADER)); bi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER); HDC hdc = GetDC(hwnd); if(!GetDIBits(hdc, bitmap, 0, bi.bmiHeader.biHeight, NULL, &bi, DIB_RGB_COLORS)) MessageBox(NULL, "Can't get base image info!", "Error!", MB_ICONEXCLAMATION | MB_OK); // Allocate memory for bitmap bits int size = height * width; Pixel* newPixels = new Pixel[size]; // Recompute the output //memcpy(newPixels, pixels, size*3); ComputeOutput(newPixels, tol1, tol2, useWhite, useBackground); // Push back to windows if(!SetDIBits(hdc, bitmap, 0, bi.bmiHeader.biHeight, newPixels, &bi, DIB_RGB_COLORS)) MessageBox(NULL, "Can't set pixel data!", "Error!", MB_ICONEXCLAMATION | MB_OK); delete newPixels; } where the Pixel struct is just this: struct Pixel { unsigned char b, g, r; }; Why does my update function not work. I always get the MessageBox for "Can't set pixel data!" I used code similar to this when I was loading in the original bitmap from file, then editing the data, but now when I manually create it, it doesn't work.

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  • trying to make this code less messy in android, can anyone help?

    - by clayton33
    i know that there must be a simpler way of doing this, i just don't understand how java works well enough, and i am struggling. could someone perhaps point me in the right direction? ImageButton image = (ImageButton) findViewById(R.id.card1); ImageButton image2 = (ImageButton) findViewById(R.id.card2); ImageButton image3 = (ImageButton) findViewById(R.id.card3); ImageButton image4 = (ImageButton) findViewById(R.id.card4); ImageButton image5 = (ImageButton) findViewById(R.id.card5); ImageButton image6 = (ImageButton) findViewById(R.id.card6); ImageButton image7 = (ImageButton) findViewById(R.id.card7); ImageButton image8 = (ImageButton) findViewById(R.id.card8); ImageButton image9 = (ImageButton) findViewById(R.id.card9); ImageButton image10 = (ImageButton) findViewById(R.id.card10); ImageButton image11 = (ImageButton) findViewById(R.id.card11); ImageButton image12 = (ImageButton) findViewById(R.id.card12); ImageButton image13 = (ImageButton) findViewById(R.id.card13); ImageButton image14 = (ImageButton) findViewById(R.id.card14); ImageButton image15 = (ImageButton) findViewById(R.id.card15); //image.setImageResource(R.drawable.test2); Bitmap bMap = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled = Bitmap.createScaledBitmap(bMap, buttonSize, buttonSize, true); Bitmap bMap2 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled2 = Bitmap.createScaledBitmap(bMap2, buttonSize, buttonSize, true); Bitmap bMap3 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled3 = Bitmap.createScaledBitmap(bMap3, buttonSize, buttonSize, true); Bitmap bMap4 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled4 = Bitmap.createScaledBitmap(bMap4, buttonSize, buttonSize, true); Bitmap bMap5 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled5 = Bitmap.createScaledBitmap(bMap5, buttonSize, buttonSize, true); Bitmap bMap6 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled6 = Bitmap.createScaledBitmap(bMap6, buttonSize, buttonSize, true); Bitmap bMap7 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled7 = Bitmap.createScaledBitmap(bMap7, buttonSize, buttonSize, true); Bitmap bMap8 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled8 = Bitmap.createScaledBitmap(bMap8, buttonSize, buttonSize, true); Bitmap bMap9 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled9 = Bitmap.createScaledBitmap(bMap9, buttonSize, buttonSize, true); Bitmap bMap10 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled10 = Bitmap.createScaledBitmap(bMap10, buttonSize, buttonSize, true); Bitmap bMap11 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled11 = Bitmap.createScaledBitmap(bMap11, buttonSize, buttonSize, true); Bitmap bMap12 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled12 = Bitmap.createScaledBitmap(bMap12, buttonSize, buttonSize, true); Bitmap bMap13 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled13 = Bitmap.createScaledBitmap(bMap13, buttonSize, buttonSize, true); Bitmap bMap14 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled14 = Bitmap.createScaledBitmap(bMap14, buttonSize, buttonSize, true); Bitmap bMap15 = BitmapFactory.decodeResource(getResources(), R.drawable.vraag); Bitmap bMapScaled15 = Bitmap.createScaledBitmap(bMap15, buttonSize, buttonSize, true); image.setImageBitmap(bMapScaled); image2.setImageBitmap(bMapScaled2); image3.setImageBitmap(bMapScaled3); image4.setImageBitmap(bMapScaled4); image5.setImageBitmap(bMapScaled5); image6.setImageBitmap(bMapScaled6); image7.setImageBitmap(bMapScaled7); image8.setImageBitmap(bMapScaled8); image9.setImageBitmap(bMapScaled9); image10.setImageBitmap(bMapScaled10); image11.setImageBitmap(bMapScaled11); image12.setImageBitmap(bMapScaled12); image13.setImageBitmap(bMapScaled13); image14.setImageBitmap(bMapScaled14); image15.setImageBitmap(bMapScaled15);

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  • FreeType2 Bitmap to System::Drawing::Bitmap.

    - by Dennis Roche
    Hi, I'm trying to convert a FreeType2 bitmap to a System::Drawing::Bitmap in C++/CLI. FT_Bitmap has a unsigned char* buffer that contains the data to write. I have got somewhat working save it disk as a *.tga, but when saving as *.bmp it renders incorrectly. I believe that the size of byte[] is incorrect and that my data is truncated. Any hints/tips/ideas on what is going on here would be greatly appreciated. Links to articles explaining byte layout and pixel formats etc. would be helpful. Thanks!! C++/CLI code. FT_Bitmap *bitmap = &face->glyph->bitmap; int width = (face->bitmap->metrics.width / 64); int height = (face->bitmap->metrics.height / 64); // must be aligned on a 32 bit boundary or 4 bytes int depth = 8; int stride = ((width * depth + 31) & ~31) >> 3; int bytes = (int)(stride * height); // as *.tga void *buffer = bytes ? malloc(bytes) : NULL; if (buffer) { memset(buffer, 0, bytes); for (int i = 0; i < glyph->rows; ++i) memcpy((char *)buffer + (i * width), glyph->buffer + (i * glyph->pitch), glyph->pitch); WriteTGA("Test.tga", buffer, width, height); } array<Byte>^ values = gcnew array<Byte>(bytes); Marshal::Copy((IntPtr)glyph->buffer, values, 0, bytes); // as *.bmp Bitmap^ systemBitmap = gcnew Bitmap(width, height, PixelFormat::Format24bppRgb); // create bitmap data, lock pixels to be written. BitmapData^ bitmapData = systemBitmap->LockBits(Rectangle(0, 0, width, height), ImageLockMode::WriteOnly, bitmap->PixelFormat); Marshal::Copy(values, 0, bitmapData->Scan0, bytes); systemBitmap->UnlockBits(bitmapData); systemBitmap->Save("Test.bmp"); Reference, FT_Bitmap typedef struct FT_Bitmap_ { int rows; int width; int pitch; unsigned char* buffer; short num_grays; char pixel_mode; char palette_mode; void* palette; } FT_Bitmap; Reference, WriteTGA bool WriteTGA(const char *filename, void *pxl, uint16 width, uint16 height) { FILE *fp = NULL; fopen_s(&fp, filename, "wb"); if (fp) { TGAHeader header; memset(&header, 0, sizeof(TGAHeader)); header.imageType = 3; header.width = width; header.height = height; header.depth = 8; header.descriptor = 0x20; fwrite(&header, sizeof(header), 1, fp); fwrite(pxl, sizeof(uint8) * width * height, 1, fp); fclose(fp); return true; } return false; }

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  • Round bottom corners on Android Bitmap?

    - by alex
    Hey all, what would be best practice for clipping the bottom borders of a Bitmap? Just manipulate the Bitmap itself or overlay an alpha mask drawable or ...? The whole story: I've a Listview which looks like the iPhone's grouped UITableView style. I would like to display a Bitmap in the last row, but for now the Bitmap overlaps my custom background drawable of the Listview cell. Thx in advance!

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  • c# Bitmap.Save transparancy doesn't save in png

    - by kelton52
    I'm trying to save a Bitmap class that has transparancy as a png file with transparancy. I'm having no luck. The bitmap has transparancy, it just doesn't save with transparancy. this is what I'm doing bitmap setup Bitmap ret = new Bitmap(bWidth, bHeight, System.Drawing.Imaging.PixelFormat.Format32bppArgb); saveing ret.Save(filename, ImageFormat.Png); I also tried saving the file with a filestream, and that made no difference. When the image is in a Picture box the transparancy exists, but when I save i I just get a black background. I really don't want to use any 3rd party code, they found a way to do it, I'd like to also. thanks.

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  • How to convert a AChartEngine chart to bitmap

    - by user2137817
    I want to convert a line graph I made with AChartEngine lib to bitmap.How should I do?I didn't found on the net anything that can help. Is the toBitmap() method suitable?if yes then how to use it? Update: I used this method : public static Bitmap loadBitmapFromView(View v) { v.setDrawingCacheEnabled(true); v.layout( 0,0,800,600); v.setDrawingCacheQuality(View.DRAWING_CACHE_QUALITY_HIGH); v.buildDrawingCache(); v.getDrawingCache(); Bitmap bmp = Bitmap.createBitmap(800,600, Bitmap.Config.ARGB_8888); v.setDrawingCacheEnabled(false); return bmp; } and saved the result in a png file but all I got is an empty file !

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  • How can you extend the Bitmap class

    - by vrish88
    Hello, I am trying to extend the Bitmap class so that I can apply my own effects to an image. When I use this code: namespace ImageEditor { public class Effects : System.Drawing.Bitmap { public void toBlackAndWhite() { System.Drawing.Bitmap image = (Bitmap)this; AForge.Imaging.Filters.Grayscale filter = new AForge.Imaging.Filters.Grayscale(); this = filter.Apply(this); } } } I get the following error: 'ImageEditor.Effects': cannot derive from sealed type 'System.Drawing.Bitmap' So is there a way to get around this or is it simply not possible to extend the class? Thanks.

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  • Load a bitmap from file in RGB format (without alpha)

    - by Robert
    Hi, i simply want to load a .BMP file and get the Bitmap object in 24bit RGB format (or 32bit in RGB format). All methods I tried return a Bitmap/Image object with PixelFormat = Format32bppArgb. Even if of course BMPs don't have alpha. new Bitmap(System.Drawing.Image.FromFile(fileName, true)); new Bitmap(fileName); I currently solve the problem by copying the first object to another in memory bitmap at 24bit RBG. Is there a single method to do it? Thanks

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  • Access to bytes array of a Bitmap

    - by Deulis
    1- In Windows CE, I have a Bitmap object in C#. 2- I have a C function in an extern dll that expects as parameters the pointer to a bytes array that represents an image in RGB565 format, width and height. This function will draw on this array of bytes. So I need to pass the byte array pointer of the Bitmap object, but I can find a practical way to get this pointer. One way is convert this Bitmap into a bytes array using a memory stream or something else, but it will create a new bytes array, so I will keep in memory both object, the Bitmap and the bytes array, but I don’t want it because the few available memory, that’s why I need to access to the bytes array of the bitmap object, not create a new bytes array. Anyone can help me?

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  • How to genrate a monochrome bit mask for a 32bit bitmap

    - by Mordachai
    Under Win32, it is a common technique to generate a monochrome bitmask from a bitmap for transparency use by doing the following: SetBkColor(hdcSource, clrTransparency); VERIFY(BitBlt(hdcMask, 0, 0, bm.bmWidth, bm.bmHeight, hdcSource, 0, 0, SRCCOPY)); This assumes that hdcSource is a memory DC holding the source image, and hdcMask is a memory DC holding a monochrome bitmap of the same size (so both are 32x32, but the source is 4 bit color, while the target is 1bit monochrome). However, this seems to fail for me when the source is 32 bit color + alpha. Instead of getting a monochrome bitmap in hdcMask, I get a mask that is all black. No bits get set to white (1). Whereas this works for the 4bit color source. My search-foo is failing, as I cannot seem to find any references to this particular problem. I have isolated that this is indeed the issue in my code: i.e. if I use a source bitmap that is 16 color (4bit), it works; if I use a 32 bit image, it produces the all-black mask. Is there an alternate method I should be using in the case of 32 bit color images? Is there an issue with the alpha channel that overrides the normal behavior of the above technique? Thanks for any help you may have to offer! ADDENDUM: I am still unable to find a technique that creates a valid monochrome bitmap for my GDI+ produced source bitmap. I have somewhat alleviated my particular issue by simply not generating a monochrome bitmask at all, and instead I'm using TransparentBlt(), which seems to get it right (but I don't know what they're doing internally that's any different that allows them to correctly mask the image). It might be useful to have a really good, working function: HBITMAP CreateTransparencyMask(HDC hdc, HBITMAP hSource, COLORREF crTransparency); Where it always creates a valid transparency mask, regardless of the color depth of hSource. Ideas?

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  • Preserving Bitmap values when creating a new Bitmap from System.Drawing.Image

    - by Otaku
    I'm trying to create a resized image from a bitmap, set a new height/width and a new resolution and save it to PNG. I can do this either from directly A) Image.FromFile(filename) or B) New Bitmap(imageSource) to create the the A Bitmap to be passed to B. Both work okay schmokay, but A does not allow me to set a new width/height on creation (but it does allow me to preserve values with useIcm=True) and B does not allow me to preseve values. Okay, now on to some code and examples: Dim sourceBitmap As New Bitmap(imagePath & myImage1Name) <-not good at all (#1 overload). Doesn't preserve things like HorizontalResolution or PixelFormat on .Save Dim sourceBitmap2 As Bitmap = Image.FromFile(imagePath & myImage1Name, True) <-not good (#5 overload). it does preserve things like HorizontalResolution or PixelFormat on .Save, but it doesn't allow me to initialize image at a new size. Dim targetBitmap As New Bitmap(sourceBitmap2, newWidth, newHeight) <-not good. Even though sourceBitmap2 (see #2 above) was initialized with useIcm=True, it doesn't matter once I've passed it in as the source in targetBitmap. Basically, I'm looking for a way to contruct a New Bitmap with both something like useIcm=True and set the width/height at the same time (Width/Height are read-only properties once it's created). I've gone down the Graphics.DrawImage route as well and it's the same - Graphics.FromImage(sourceBitmap) does not preserve values. Why do I need these values to be preserved? Because I need to convert these pictures to PNG (for file size) with a new resolution and keep the same physical dimensions (w/h in inches) for printing. I know the new pixel width/height needed based on the resolution values I'll pass in with .SetResolution(xDpi,yDpi) to preserve physical dimensions, so that's not the problem. The issue is things like the PixelFormatSize need to remain unchanged (yes, I've tried EncoderParameters - they don't work. I can give you the gory details if you like, but suffice it to say for now, they just don't work). Whew, got that off my chest! Okay, anyone who really knows how all this works can help?

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  • Android: problem retrieving bitmap from database

    - by Addy
    When I'm retrieving image from the sqlite database my Bitmap object bm return null value can any one help me..? I found problem in my database.. When I store the byte array in blob data type in database table that time the size of the byte array was 2280.. But when i retrieved that blob data type using select query I get the byte array within size 12. My code is: // Inserting data in database byte[] b; ByteArrayOutputStream baos = new ByteArrayOutputStream(); Bitmap bm = BitmapFactory.decodeResource(getResources(),R.drawable.icon); bm.compress(Bitmap.CompressFormat.PNG, 100, baos); //bm is the bitmap object b = baos.toByteArray(); //here b size is 2280 baos.close(); try { mDB = this.openOrCreateDatabase(MY_DATABASE_NAME, MODE_PRIVATE, null); mDB.execSQL("CREATE TABLE IF NOT EXISTS " + MY_DATABASE_TABLE + " (PICTURE BLOB);"); mDB.execSQL("INSERT INTO " + MY_DATABASE_TABLE + " (PICTURE)" + " VALUES ('"+b+"');"); } catch(Exception e) { Log.e("Error", "Error", e); } finally { if(mDB != null) mDB.close(); } // Retriving data from database byte[] b1; Bitmap bm; mDB = this.openOrCreateDatabase(MY_DATABASE_NAME, MODE_PRIVATE, null); try { mDB.execSQL("CREATE TABLE IF NOT EXISTS " + MY_DATABASE_TABLE + " (PICTURE BLOB);"); Cursor c = mDB.rawQuery("SELECT * FROM " + MY_DATABASE_TABLE + ";", null); c.moveToFirst(); if (c != null) { do { b1=c.getBlob(0)); //here b1 size is 12 bm=BitmapFactory.decodeByteArray(b1, 0, b1.length); }while(c.moveToNext()); }

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