SDL入门（二）代码模板

一时失言乱红尘 2022-08-20 05:22 7阅读 0赞

流程图见http://blog.csdn.net/leixiaohua1020/article/details/38868499

// 0202_2.cpp : 定义控制台应用程序的入口点。
    //
    
    #include "stdafx.h"
    
    /**
     * 最简单的SDL2播放视频的例子（SDL2播放RGB/YUV）
     * Simplest Video Play SDL2 (SDL2 play RGB/YUV) 
     *
     * 雷霄骅 Lei Xiaohua
     * leixiaohua1020@126.com
     * 中国传媒大学/数字电视技术
     * Communication University of China / Digital TV Technology
     * http://blog.csdn.net/leixiaohua1020
     *
     * 本程序使用SDL2播放RGB/YUV视频像素数据。SDL实际上是对底层绘图
     * API（Direct3D，OpenGL）的封装，使用起来明显简单于直接调用底层
     * API。
     *
     * 函数调用步骤如下: 
     *
     * [初始化]
     * SDL_Init(): 初始化SDL。
     * SDL_CreateWindow(): 创建窗口（Window）。
     * SDL_CreateRenderer(): 基于窗口创建渲染器（Render）。
     * SDL_CreateTexture(): 创建纹理（Texture）。
     *
     * [循环渲染数据]
     * SDL_UpdateTexture(): 设置纹理的数据。
     * SDL_RenderCopy(): 纹理复制给渲染器。
     * SDL_RenderPresent(): 显示。
     *
     * This software plays RGB/YUV raw video data using SDL2.
     * SDL is a wrapper of low-level API (Direct3D, OpenGL).
     * Use SDL is much easier than directly call these low-level API.  
     *
     * The process is shown as follows:
     *
     * [Init]
     * SDL_Init(): Init SDL.
     * SDL_CreateWindow(): Create a Window.
     * SDL_CreateRenderer(): Create a Render.
     * SDL_CreateTexture(): Create a Texture.
     *
     * [Loop to Render data]
     * SDL_UpdateTexture(): Set Texture's data.
     * SDL_RenderCopy(): Copy Texture to Render.
     * SDL_RenderPresent(): Show.
     */
    
    #include <stdio.h>
    
    #include "SDL/SDL.h"
    
    const int bpp=12;
    
    int screen_w=352,screen_h=288;
    const int pixel_w=352,pixel_h=288;
    
    unsigned char buffer[pixel_w*pixel_h*bpp/8];
    
    
    //Refresh Event
    #define REFRESH_EVENT  (SDL_USEREVENT + 1)
    
    #define BREAK_EVENT  (SDL_USEREVENT + 2)
    
    int thread_exit=0;
    
    int refresh_video(void *opaque){
    	thread_exit=0;
    	while (!thread_exit) {
    		SDL_Event event;
    		event.type = REFRESH_EVENT;
    		SDL_PushEvent(&event);
    		SDL_Delay(40);
    	}
    	thread_exit=0;
    	//Break
    	SDL_Event event;
    	event.type = BREAK_EVENT;
    	SDL_PushEvent(&event);
    
    	return 0;
    }
    
    int _tmain(int argc, _TCHAR* argv[])
    {
    	if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO)) {  
    		printf( "Could not initialize SDL - %s\n", SDL_GetError()); 
    		return -1;
    	} 
    
    	SDL_Window *screen; 
    	//SDL 2.0 Support for multiple windows
    	screen = SDL_CreateWindow("Simplest Video Play SDL2", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
    		screen_w, screen_h,SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE);
    	if(!screen) {  
    		printf("SDL: could not create window - exiting:%s\n",SDL_GetError());  
    		return -1;
    	}
    	SDL_Renderer* sdlRenderer = SDL_CreateRenderer(screen, -1,  SDL_RENDERER_SOFTWARE);
    	
    	Uint32 pixformat=0;
    
    	//IYUV: Y + U + V  (3 planes)
    	//YV12: Y + V + U  (3 planes)
    	pixformat= SDL_PIXELFORMAT_IYUV;  
    
    	SDL_Texture* sdlTexture = SDL_CreateTexture(sdlRenderer,pixformat, SDL_TEXTUREACCESS_STREAMING,pixel_w,pixel_h);
    
    	FILE *fp=NULL;
    	fp=fopen("BigBuckBunny_CIF_24fps.yuv","rb+");
    
    	if(fp==NULL){
    		printf("cannot open this file\n");
    		return -1;
    	}
    
    	SDL_Rect sdlRect;  
    
    	SDL_Thread *refresh_thread = SDL_CreateThread(refresh_video,NULL,NULL);
    	SDL_Event event;
    	while(1){
    		//Wait
    		SDL_WaitEvent(&event);
    		if(event.type==REFRESH_EVENT){
    			if (fread(buffer, 1, pixel_w*pixel_h*bpp/8, fp) != pixel_w*pixel_h*bpp/8){
    				// Loop
    				fseek(fp, 0, SEEK_SET);
    				fread(buffer, 1, pixel_w*pixel_h*bpp/8, fp);
    			}
    
    			SDL_UpdateTexture( sdlTexture, NULL, buffer, pixel_w);  
    
    			//FIX: If window is resize
    			sdlRect.x = 0;  
    			sdlRect.y = 0;  
    			sdlRect.w = screen_w;  
    			sdlRect.h = screen_h;  
    			
    			SDL_RenderClear( sdlRenderer );   
    			SDL_RenderCopy( sdlRenderer, sdlTexture, NULL, &sdlRect);  
    			SDL_RenderPresent( sdlRenderer );  
    			
    		}else if(event.type==SDL_WINDOWEVENT){
    			//If Resize
    			SDL_GetWindowSize(screen,&screen_w,&screen_h);
    		}else if(event.type==SDL_QUIT){
    			thread_exit=1;
    		}else if(event.type==BREAK_EVENT){
    			break;
    		}
    	}
    	SDL_Quit();
    	
    	getchar();
    	return 0;
    }