Android Graphic System Acceleration Based on DirectFB

In this study, based on analyzing the hardware abstraction layer and native graphics libraries of Android graphics system, the drawback of Skia library which could only support software rendering is pointed out. And then the third-party open graphics library DirectFB which supports 2D hardware acceleration is introduced, the architecture and interface of DirectFB and Skia are analyzed and compared with each other in detail. After DirectFB being ported into Android system, a novel hardware acceleration layer with double-buffer technology is designed and implemented, which will make Skia and DirectFB coexist and complement with each other and ultimately implement the 2D hardware acceleration in Android system. A JNI interface is designed for Java programs. The optimization scheme is verified by the specialized test benchmarks df-dok, the experimental results indicated that the performance of Android graphics system in layer blending operations is accelerated by an average of 5.58x as well as 2.18x speedup on average in bitblit operations when processing complex graphics operations such as layer blending and bitblit etc.