研究了一段时间Android的surface系统，一直执着地认为所有在surface或者屏幕上显示的画面，必须要转换成RGB才能显示，yuv数据也要通过颜色空间转换成RGB才能显示。可最近在研究stagefright视频显示时发现，根本找不到omx解码后的yuv是怎么转换成RGB的代码，yuv数据在render之后就找不到去向了，可画面确确实实的显示出来了，这从此颠覆了yuv必须要转换成RGB才能显示的真理了。

    稍微看一下AsomePlayer的代码，不难发现，视频的每一帧是通过调用了SoftwareRenderer来渲染显示的，我也尝试用利用SoftwareRenderer来直接render yuv数据显示，竟然成功了，这是一个很大的突破，比如以后摄像头采集到的yuv，可以直接丢yuv数据到surface显示，无需耗时耗效率的yuv转RGB了。

    代码原创，贴出来与大家分享：Android 4.4平台 （其中yuv数据的地址可以从这里下载点击打开链接，放到/mnt/sdcard目录）

#include<include/SoftwareRenderer.h>

#include <cutils/memory.h>

#include <unistd.h>
#include <utils/Log.h>

#include <binder/IPCThreadState.h>
#include <binder/ProcessState.h>
#include <binder/IServiceManager.h>

#include <gui/Surface.h>
#include <gui/SurfaceComposerClient.h>
#include <gui/ISurfaceComposer.h>
#include <ui/DisplayInfo.h>
#include <android/native_window.h>
#include <media/stagefright/MetaData.h>
 
using namespace android;

bool getYV12Data(const char *path,unsigned char * pYUVData,int size){
	FILE *fp = fopen(path,"rb");
	if(fp == NULL){
		printf("read %s fail !!!!!!!!!!!!!!!!!!!\n",path);
		return false;
	}
	fread(pYUVData,size,1,fp);
	fclose(fp);
	return true;
}

int main(void){
	// set up the thread-pool
    sp<ProcessState> proc(ProcessState::self());
    ProcessState::self()->startThreadPool();
	
	// create a client to surfaceflinger
    sp<SurfaceComposerClient> client = new SurfaceComposerClient();
	sp<IBinder> dtoken(SurfaceComposerClient::getBuiltInDisplay(
            ISurfaceComposer::eDisplayIdMain));
	DisplayInfo dinfo;
	//获取屏幕的宽高等信息
    status_t status = SurfaceComposerClient::getDisplayInfo(dtoken, &dinfo);
	printf("w=%d,h=%d,xdpi=%f,ydpi=%f,fps=%f,ds=%f\n", 
        dinfo.w, dinfo.h, dinfo.xdpi, dinfo.ydpi, dinfo.fps, dinfo.density);
    if (status)
        return -1;
	//创建surface,有些系统可能报错，dinfo.w和dinfo.h也可以写成固定值
    sp<SurfaceControl> surfaceControl = client->createSurface(String8("showYUV"),
            dinfo.w, dinfo.h, PIXEL_FORMAT_RGBA_8888, 0);
			
/*************************get yuv data from file;****************************************/			
	printf("[%s][%d]\n",__FILE__,__LINE__);
	int width,height;
	width = 320;
	height = 240;
	int size = width * height * 3/2;
	unsigned char *data = http://www.mamicode.com/new unsigned char[size];>
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)

LOCAL_SRC_FILES:= 	main.cpp

LOCAL_STATIC_LIBRARIES := 	libstagefright_color_conversion
	
LOCAL_SHARED_LIBRARIES := 	libcutils 	libutils 	libbinder     libui     libgui 	libstagefright	libstagefright_foundation
	
LOCAL_C_INCLUDES := 	frameworks/native/include/media/openmax     frameworks/av/media/libstagefright

	
LOCAL_MODULE:= showYUV

LOCAL_MODULE_TAGS := tests

include $(BUILD_EXECUTABLE)