Cloo OutOfResourcesComputeException when trying to process successive image buffers

    class MHCdemosaic : IDemosaic
    {
        private ComputeProgram program;
        private ComputeKernel kernel;
 
        public MHCdemosaic()
        {
            // Init OpenCL
            // For now use the first platform and first device thereof for the context
            ComputePlatform platform = ComputePlatform.Platforms[0];
            List<ComputeDevice> devices = new List<ComputeDevice>();
            devices.Add(platform.Devices[0]);
 
            ComputeContextPropertyList properties = new ComputeContextPropertyList(platform);
            ComputeContext cc = new ComputeContext(devices, properties, null, IntPtr.Zero);
 
            // Setup the program and its kernel
            program = new ComputeProgram(cc, LoadSource("MHCdemosaic.cl"));
            program.Build(null, null, null, IntPtr.Zero);
            if (kernel != null)
                kernel.Dispose();
            kernel = program.CreateKernel("MHCdemosaic");
        }
 
        public Bitmap Demosaic(byte[,] bayer)        // needs a 1D array, not 2D like others
        {
            // temporary "flatten" to 1D to send to GPU
            byte[] mosaic = new byte[bayer.Length];
            int height = bayer.GetLength(0);
            int width = bayer.GetLength(1);
            for (int y = 0; y < height; y++)
                for (int x = 0; x < width; x++)
                    mosaic[x + y * width] = bayer[y, x];
 
            byte[] bimage = new byte[bayer.Length * 3];
 
            //  Setup input buffer
            using (ComputeBuffer<byte> imageIn = new ComputeBuffer<byte>(kernel.Context, ComputeMemoryFlags.ReadOnly | ComputeMemoryFlags.CopyHostPointer, mosaic))
            {
                // Setup output buffer
                using (ComputeBuffer<byte> imageOut = new ComputeBuffer<byte>(kernel.Context, ComputeMemoryFlags.WriteOnly, bimage.Length))
                {
                    // Set arguments
                    kernel.SetMemoryArgument(0, imageIn);
                    kernel.SetMemoryArgument(1, imageOut);
 
                    using (ComputeCommandQueue cq = new ComputeCommandQueue(kernel.Context, kernel.Context.Devices[0], ComputeCommandQueueFlags.None))
                    {
                        // Execute
                        cq.Execute(kernel, null, new long[] { width, height }, null, null);
 
                        // Get the color buffer
                        cq.ReadFromBuffer(imageOut, ref bimage, false, null);
 
                        // Convert to Bitmap and return
                        return CreateBitmap(bimage, width, height);
                    }
                }
            }
        }
 
        private Bitmap CreateBitmap(byte[] buffer, int width, int height)
        {
            Bitmap newBitmap = new Bitmap(width, height, PixelFormat.Format24bppRgb);
            BitmapData newData = newBitmap.LockBits(new Rectangle(0, 0, width, height),
                ImageLockMode.WriteOnly, PixelFormat.Format24bppRgb);
            int stride = newData.Stride;
            IntPtr ptr = newData.Scan0;
            System.Runtime.InteropServices.Marshal.Copy(buffer, 0, ptr, stride * height);
            newBitmap.UnlockBits(newData);
            return newBitmap;
        }
    }