StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

POHow to create a BitmapImage from a pixel byte array (live video display)
primarykey
Id
16220472
data
AcceptedAnswerId
16220704
AnswerCount
1
ClosedDate
CommentCount
4
CommunityOwnedDate
CreationDate
2013-04-25T16:50:44.433
FavoriteCount
11
LastActivityDate
2013-05-28T17:03:26.253
LastEditDate
2017-05-23T12:17:11.370
LastEditorUserId
-1
OwnerUserId
767664
ParentId
0
PostTypeId
1
Score
6
ViewCount
10225
LastEditorDisplayName
text
Body
I need to display live images on a WPF control. I'm looking for the fastest way to do this using WPF. I'm capturing images from a camera using its dll API (<a href="http://www.alliedvisiontec.com/us/products/software/windows/avt-pvapi-sdk.html" rel="nofollow noreferrer">AVT</a>). The image is writen by the dll and the camera rises a callback with an IntPtr to a Image struct called tFrame (described below). The pixel data is stored at the ImageBuffer propertie with is an InPtr to a byte array. I know how to create a Bitmap from the pixel byte array, but not a BitmapImage. So it is possible to create a Bitmap and then create a BitmapImagem from it. <a href="https://stackoverflow.com/questions/1118496/using-image-control-in-wpf-to-display-system-drawing-bitmap/1118557#1118557">Here there is a way to create a BitmapImage from a Bitmap on the memory</a>. But I want to create the BitmapImage directly from the data source (tFrame). How can I do that? I know that BitmapImage have a CopyPixels method, but it laks of a SetPixels. <pre><code>public struct tFrame { public IntPtr AncillaryBuffer; public uint AncillaryBufferSize; public uint AncillarySize; public tBayerPattern BayerPattern; public uint BitDepth; public tFrameCtx Context; public tImageFormat Format; public uint FrameCount; public uint Height; public IntPtr ImageBuffer; public uint ImageBufferSize; public uint ImageSize; public uint RegionX; public uint RegionY; public tErr Status; public uint TimestampHi; public uint TimestampLo; public uint Width; } </code></pre> Here is how I create a Bitmap from a pixel byte array. This was used at the WinForm version of the software. <pre><code>private void CreateBitmap(tFrame frame) { //This sample is for a 8bpp captured image PixelFormat pxFormat = PixelFormat.Format8bppIndexed; //STRIDE //[https://stackoverflow.com/questions/1983781/why-does-bitmapsource-create-throw-an-argumentexception/1983886#1983886][3] //float bitsPerPixel = System.Drawing.Image.GetPixelFormatSize(format); int bitsPerPixel = ((int)pxFormat >> 8) & 0xFF; //Number of bits used to store the image data per line (only the valid data) int validBitsPerLine = ((int)frame.Width) * bitsPerPixel; //4 bytes for every int32 (32 bits) int stride = ((validBitsPerLine + 31) / 32) * 4; Bitmap bmp = new Bitmap((int)frame.Width, (int)frame.Height, stride, pxFormat, frame.ImageBuffer); } </code></pre> <hr> EDIT 1: Thanks to dr.mo, now I'm able to display 60 FPS 1024x1024 images with ~3% CPU usage! What I'm doing is: <pre><code>//@ UI Thread public WriteableBitmap wbm = new WriteableBitmap(1024, 1024, (double)96, (double)96, System.Windows.Media.PixelFormats.Gray8, null); this.wbBackBuffer = this.wbm.BackBuffer; //This can be called by a timer in the UI thread or at the grab Thread for every image, the CPU usage is almost the same. void UpdateDisplayImage() { wbm.Lock(); wbm.AddDirtyRect(new Int32Rect(0, 0, wbm.PixelWidth, wbm.PixelHeight)); wbm.Unlock(); } //@ Grab Thread //Update the backbuffer with new camera image data. UpdateBackBuffer(...); /// <summary> /// [http://msdn.microsoft.com/en-us/library/system.windows.media.imaging.writeablebitmap.aspx] /// </summary> public void UpdateBackBuffer(IntPtr pData, int w, int h, int ch) { //Can not acess wbm from outside UI thread //CopyMemory(wbm.BackBuffer, pData, (uint)(w * h * ch)); //I dont know if it is safe to write to it buffer like this: CopyMemory(this.wbBackBuffer, pData, (uint)(w * h * ch)); } </code></pre>
Tags
<c#><wpf><video-capture><bitmapimage>
Title
How to create a BitmapImage from a pixel byte array (live video display)
singulars
PostAcceptedAnswerId
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
PostParentId
1. This table or related slice is empty.
PostTypePostTypeId
1. PTQuestion
UserLastEditorUserId
1. USCommunity
UserOwnerUserId
1. USPedro77
plurals
PostLinksPostIdRelatedPostId
1. PL
 singulars
 LinkTypeLinkTypeId
 LTLinked
2. PL
 singulars
 LinkTypeLinkTypeId
 LTLinked
3. PL
 singulars
 LinkTypeLinkTypeId
 LTLinked
PostLinksRelatedPostIdPostId
1. PL
 singulars
 LinkTypeLinkTypeId
 LTLinked
2. PL
 singulars
 LinkTypeLinkTypeId
 LTLinked
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 POHow to create a BitmapImage from a pixel byte array (live video display)
 UserUserId
 USPedro77
 VoteTypeVoteTypeId
 VTFavorite
2. VO
 singulars
 PostPostId
 POHow to create a BitmapImage from a pixel byte array (live video display)
 UserUserId
 USNanhydrin
 VoteTypeVoteTypeId
 VTFavorite
3. VO
 singulars
 PostPostId
 POHow to create a BitmapImage from a pixel byte array (live video display)
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
CommentsPostId

Querying!

Guidance

A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.