Pixel Bender Disco
While playing with pixel bender, I created some simple sahders that when combined, reminds me of winamp visualizations effects. Feel free to use any in your own projects.
SmoothImage Class (update)
While Flex uses bilinear resizing method when scaling images (event for Bitmap.smoothing() method), you won’t be able to get nice results when downscaling more than 2 times. Inspired by ImageResizer class I have also created SmoothImage Class. This object extends mx.Image and uses ImageResizer.bilinearIterative() class in order to generate smoother resized results.
How to resize an image with ActionScript (update)
If you need to resize an image on client side, I mean real bitmapData resize (not just showing scaled), feel free to use ImageResizer class. This class takes bitmapData of source image, new width and height and resize method (defined by ResizeMath class), and returns new bitmapData of resized image.
Update: It seems that bitmapData.draw() method uses bilinear algorithm when scaling via Matrix. Bilinear algorithm gives you fine results when downscaling no more than 2 times (400px -> 200px). So, I added bilinearIterative() method into ImageResizer class that creates resized bitmapData by multiple steps achieving much smoother results!
Frame rate optimization
There has been a lot of articles written about how to optimize your flash / flex application frameRate. In most cases, you only need to have full frameRate when some animation is playing, or tweening etc., in other words when some visual changes are going on. FrameRateOptimizator class does exactly what you need. In default, it uses full frameRate when visual changes and when it stops, optimizator automatically switches to lower frameRate. Optimizator uses bitmapData to compare last state with actual state to catch any visual changes. By default snapshot is executed two times per second in low frameRate (inactive state), or one time per second in full frameRate state (active state), taking approximately not more than 10ms per execution (fast enough).
- sk.yoz.optimization.FrameRateOptimizator
- Application
Bitmap, BitmapData, ByteArray…
Lets see how to convert between Bitmap, BitmapData and ByteArray in few examples:
- DisplayObject to BitmapData
- BitmapData to Bitmap
- BitmapData to ByteArray
- URL (image) to ByteArray (asynchronous)
- URL (image) to BitmapData (asynchronous)
- ByteArray to BitmapData (asynchronous)
ActionScript 3 encoding JPEG, alchemy
Lets assume you want to save an image (or any DisplayObject) from flash to disk, or upload to facebook etc. What you need is to encode your BitmapData into an Jpeg and send ByteArray raw data to be saved/uploaded. There are few ways how to do it.
First, you can use original adobe mx.graphics.codec.JPEGEncoder. Sadly, this encoder is the slowest. There were attemps to make it faster by otpimizing code by bytearray.org, that resulted into two times faster org.bytearray.images.JPEGEncoder. Usage is pretty simple:
