How fast is 'decodeYUV' method? You call this method while your canvas is locked. If 'decodeYUV' is slow, it not only makes your background thread sluggish, but your main GUI-thread as well, because the canvas is locked for too long.
Also, you don't synchronize on '_data'... Your implementation of 'onPreviewFrame' is filling '_data' and your background thread is reading it. The filling(=arraycopy) of '_data' may not be finished before your it's being read by your background thread. On Dec 5, 9:41 pm, Greg <madma...@gmail.com> wrote: > Hello, > I've been working on creating a program that will output the Camera > Preview with various user-chosen filters (SnapPhoto has this > functionality) and I've run into some problems. > > I have the following set up. > - Camera preview set to a SurfaceView (I had to set PUSH_BUFFERS or > the program fails). > - Have another SurfaceView lieing over the Camera preview SurfaceView > (in a FrameLayout) > - Registered a camera callback for the preview data > > My problem is that the output is extremely choppy and the program > quickly becomes unresponsive. I've set up a thread to do the > processing, but this doesn't seem to help. I've implemented the > decoding (into rgb_8888) algorithm (courtesy of > dmanpearlhttp://groups.google.com/group/android-developers/msg/d3b29d3ddc8abf9b > ) Is there anything I'm doing blatantly wrong or something I could fix > to make this program run at a decent speed? Sorry if the code has poor > style, I'm sort of an Android beginner and, for that matter, Java > beginner. > > This code is inside the second SurfaceView, lieing over the Camera > preview SurfaceView > > public void onPreviewFrame(byte[] data, Camera camera) { > if(hasSurface) { > System.arraycopy(data, 0, _data, 0, > data.length); > outputThread = new HandleOutput(); > outputThread.start(); > } > } > > where HandleOutput() extends Thread, and _data is a global array. > > and this is inside the Thread > > public void run() { > while(!done) { > canvas = mHolder.lockCanvas(); > PixelManip.decodeYUV(rgb, _data, width, > height); //courtesy of > dmanpearl (link above) > PixelManip.applyFilter(filterID, _data, rgb); > bitmap.setPixels(rgb, 0, width, 0, 0, width, > height); > canvas.drawBitmap(bitmap, 0, 0, paint); > mHolder.unlockCanvasAndPost(canvas); > done = true; > } > } > > Thanks, > Greg > > P.S. Let me know if I should post any more code. -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
