Databases
StackOverflow2013
Postsdbo
POAdding Text on Image
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POAdding Text on Image
    primarykey
    data
    text
    <p>I am trying to add some text on top of a photo take by the camera, and here is the method I am using, but unfortunately I either get a closedStream error, or that there is cross-thread access when I try use the dispatcher. Could someone please explain me what is going wrong?</p> <pre><code> void cam_CaptureImageAvailable(object sender, Microsoft.Devices.ContentReadyEventArgs e) { DateTime dt = DateTime.Now; string fileName = dt.Year.ToString() + dt.Month.ToString() + dt.Day.ToString() + dt.Hour.ToString() + dt.Minute.ToString() + dt.Second.ToString() + ".jpg"; try { // Save picture to the library camera roll. library.SavePictureToCameraRoll(fileName, e.ImageStream); // Set the position of the stream back to start e.ImageStream.Seek(0, SeekOrigin.Begin); Deployment.Current.Dispatcher.BeginInvoke(() =&gt; { // load photo to writable bitmap WriteableBitmap writeableBitmap = PictureDecoder.DecodeJpeg(e.ImageStream); writeableBitmap.Invalidate(); var renderText = new TextBlock { Text = "Hello World", FontSize = 72, Foreground = new SolidColorBrush(Colors.White), FontWeight = FontWeights.Black, Width = 500, Height = 100 }; writeableBitmap.Render(renderText, new TranslateTransform() { X = 100, Y = 300 }); writeableBitmap.Invalidate(); using (var ms = new MemoryStream()) { writeableBitmap.SaveJpeg(ms, 1024, 768, 0, 100); ms.Seek(0, SeekOrigin.Begin); library.SavePicture("x" + fileName, ms); } // e.ImageStream.Close(); }); // Save picture as JPEG to isolated storage. using (IsolatedStorageFile isStore = IsolatedStorageFile.GetUserStoreForApplication()) { using (IsolatedStorageFileStream targetStream = isStore.OpenFile(fileName, FileMode.Create, FileAccess.Write)) { // Initialize the buffer for 4KB disk pages. byte[] readBuffer = new byte[4096]; int bytesRead = -1; // Copy the image to isolated storage. while ((bytesRead = e.ImageStream.Read(readBuffer, 0, readBuffer.Length)) &gt; 0) { targetStream.Write(readBuffer, 0, bytesRead); } } } } finally { // Close image stream e.ImageStream.Close(); } } </code></pre> <p>With the code above I get the following error: Cannot access a closed Stream.</p> <p>If i remove the Dispatcher, I get this error: Invalid cross-thread access.</p> <p>Thanks.</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. USteh0wner
    1. USteh0wner
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COWithout the dispatcher, on which line do you get the 'invalid cross-thread access' error?
      singulars
      1. POAdding Text on Image
      1. USKevin Gosse
    2. COthis line: WriteableBitmap writeableBitmap = PictureDecoder.DecodeJpeg(e.ImageStream);
      singulars
      1. POAdding Text on Image
      1. USteh0wner
 

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.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload