private async Task <IRandomAccessStream> GetFilteredThumbnailStreamAsync()
{
#if DEBUG
System.Diagnostics.Debug.WriteLine("GetFilteredThumbnailStreamAsync invoked " + this.GetHashCode());
#endif
IRandomAccessStream filteredStream = null;
using (var ticket = await TicketManager.AcquireTicket())
using (var stream = await _photo.GetThumbnailAsync())
{
if (Filters.Count > 0)
{
var list = Filters.Select(filter => filter.GetFilter()).ToList();
filteredStream = new InMemoryRandomAccessStream();
using (var source = new RandomAccessStreamImageSource(stream))
using (var effect = new FilterEffect(source)
{
Filters = list
})
using (var renderer = new JpegRenderer(effect))
{
var buffer = await renderer.RenderAsync();
await filteredStream.WriteAsync(buffer);
}
}
else
{
filteredStream = stream.CloneStream();
}
}
return(filteredStream);
}