OutOfMemory Exception when loading lots of Images from Isolated storage

Question

EDIT: I keep getting OutOfMemoryException was unhandled, I think it's how I am saving the image to isolated storage ,I think this is where I can solve my problem how do I reduce the size of the image before I save it? (added code where I save Image)

I am opening images from Isolated storage sometimes over 100 images and I want to loop over them images but I get a OutOfMemory Exception when there is around 100 to 150 images loaded in to a storyboard. How can I handle this exception, I have already brought down the resolution of the images. How can I handle this exception and stop my app from crashing?

I get the exception at this line here

image.SetSource(isStoreTwo.OpenFile(projectFolder + "\\MyImage" + i + ".jpg", FileMode.Open, FileAccess.Read));//images from isolated storage

here's my code

private void OnLoaded(object sender, RoutedEventArgs e)
    {


        IsolatedStorageFile isStoreTwo = IsolatedStorageFile.GetUserStoreForApplication();



        try
        {
            storyboard = new Storyboard
            {
                //RepeatBehavior = RepeatBehavior.Forever
            };

            var animation = new ObjectAnimationUsingKeyFrames();

            Storyboard.SetTarget(animation, projectImage);
            Storyboard.SetTargetProperty(animation, new PropertyPath("Source"));


            storyboard.Children.Add(animation);
            for (int i = 1; i <= savedCounter; i++)
            {
                BitmapImage image = new BitmapImage();

                image.SetSource(isStoreTwo.OpenFile(projectFolder + "\\MyImage" + i + ".jpg", FileMode.Open, FileAccess.Read));//images from isolated storage

                var keyframe = new DiscreteObjectKeyFrame
                {

                    KeyTime = KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(100 * i)),
                    Value = image
                };

                animation.KeyFrames.Add(keyframe);
            }
        }
        catch (OutOfMemoryException exc)
        {

            //throw;

        }



        Resources.Add("ProjectStoryBoard", storyboard);
        storyboard.Begin();
    }

EDIT This is how I am saving the image to Isolated storage, I think this is where I can solve my problem, How do I reduce the size of the image when saving it to isolated storage?

    void cam_CaptureImageAvailable(object sender, Microsoft.Devices.ContentReadyEventArgs e)
    {

        string fileName = folderName+"\\MyImage" + savedCounter + ".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);

            // 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)) > 0)
                    {
                        targetStream.Write(readBuffer, 0, bytesRead);
                    }

                }

            }




        }
        finally
        {
            // Close image stream
            e.ImageStream.Close();
        }

    }

I would appreciate if you could help me thanks.

Answer 1

It doesn't matter how large your images are on disk because when you load them into memory they're going to be uncompressed. The memory required for the image will be approximately (stride * height). stride is width * bitsPerPixel)/8, and then rounded up to the next multiple of 4 bytes. So an image that's 1024x768 and 24 bits per pixel will take up about 2.25 MB.

You should figure out how large your images are, uncompressed, and use that number to determine the memory requirements.