FFmpeg+SDL---柔和sdl和ffmpeg制作视频播放器

五章FFmpeg+SDL的视频播放器的制作

本章其实就是将前面两章的代码融合在一起，在阅读这章节之前建议先读：FFmpeg+SDL-----学习大纲

目录

• FFmpeg知识回顾
• SDL知识回顾
• FFmpeg和SDL的整合实现视频播放
• 进阶：脱离开发环境的独立播放器
• 练习

FFmpeg和SDL的整合实现视频播放

▫ FFmpeg解码器实现了：视频文件->YUV
▫ SDL视频显示实现了：YUV->屏幕2
▫ FFmpeg+SDL整合之后实现了：视频文件->YUV->屏幕

源代码

#include <stdio.h>

#define __STDC_CONSTANT_MACROS

extern "C"
{
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libswscale/swscale.h"
#include "SDL2/SDL.h"
};


//Refresh Event
#define SFM_REFRESH_EVENT  (SDL_USEREVENT + 1)

#define SFM_BREAK_EVENT  (SDL_USEREVENT + 2)

int thread_exit=0;

/* 新创建的线程，专门用于发送事件 */
int sfp_refresh_thread(void *opaque){
	thread_exit=0;
	while (!thread_exit) {
		SDL_Event event;
		event.type = SFM_REFRESH_EVENT;
		SDL_PushEvent(&event);
		SDL_Delay(40);
	}
	thread_exit=0;
	//Break
	SDL_Event event;
	event.type = SFM_BREAK_EVENT;
	SDL_PushEvent(&event);

	return 0;
}


int main(int argc, char* argv[])
{

	AVFormatContext	*pFormatCtx;
	int				i, videoindex;
	AVCodecContext	*pCodecCtx;
	AVCodec			*pCodec;
	AVFrame	*pFrame,*pFrameYUV;
	uint8_t *out_buffer;
	AVPacket *packet;
	int ret, got_picture;

	//------------SDL----------------
	int screen_w,screen_h;
	SDL_Window *screen; 
	SDL_Renderer* sdlRenderer;
	SDL_Texture* sdlTexture;
	SDL_Rect sdlRect;
	SDL_Thread *video_tid;
	SDL_Event event;

	struct SwsContext *img_convert_ctx;

	char filepath[]="屌丝男士.mov";

	av_register_all();
	avformat_network_init();
	pFormatCtx = avformat_alloc_context();

	if(avformat_open_input(&pFormatCtx,filepath,NULL,NULL)!=0){
		printf("Couldn't open input stream.\n");
		return -1;
	}
	if(avformat_find_stream_info(pFormatCtx,NULL)<0){
		printf("Couldn't find stream information.\n");
		return -1;
	}
	videoindex=-1;
	for(i=0; i<pFormatCtx->nb_streams; i++) 
		if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO){
			videoindex=i;
			break;
		}
	if(videoindex==-1){
		printf("Didn't find a video stream.\n");
		return -1;
	}
	pCodecCtx=pFormatCtx->streams[videoindex]->codec;
	pCodec=avcodec_find_decoder(pCodecCtx->codec_id);
	if(pCodec==NULL){
		printf("Codec not found.\n");
		return -1;
	}
	if(avcodec_open2(pCodecCtx, pCodec,NULL)<0){
		printf("Could not open codec.\n");
		return -1;
	}
	pFrame=av_frame_alloc();
	pFrameYUV=av_frame_alloc();
	out_buffer=(uint8_t *)av_malloc(avpicture_get_size(PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height));
	avpicture_fill((AVPicture *)pFrameYUV, out_buffer, PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height);
	
	img_convert_ctx = sws_getContext(pCodecCtx->width, pCodecCtx->height, pCodecCtx->pix_fmt, 
		pCodecCtx->width, pCodecCtx->height, PIX_FMT_YUV420P, SWS_BICUBIC, NULL, NULL, NULL); 
	

	if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER)) {  
		printf( "Could not initialize SDL - %s\n", SDL_GetError()); 
		return -1;
	} 
	//SDL 2.0 Support for multiple windows
	screen_w = pCodecCtx->width;
	screen_h = pCodecCtx->height;
	screen = SDL_CreateWindow("Simplest ffmpeg player's Window", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
		screen_w, screen_h,SDL_WINDOW_OPENGL);

	if(!screen) {  
		printf("SDL: could not create window - exiting:%s\n",SDL_GetError());  
		return -1;
	}
	sdlRenderer = SDL_CreateRenderer(screen, -1, 0);  
	//IYUV: Y + U + V  (3 planes)
	//YV12: Y + V + U  (3 planes)
	sdlTexture = SDL_CreateTexture(sdlRenderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING,pCodecCtx->width,pCodecCtx->height);  

	sdlRect.x=0;
	sdlRect.y=0;
	sdlRect.w=screen_w;
	sdlRect.h=screen_h;

	packet=(AVPacket *)av_malloc(sizeof(AVPacket));

	video_tid = SDL_CreateThread(sfp_refresh_thread,NULL,NULL);
	//------------SDL End------------
	//Event Loop
	
	for (;;) {
		//Wait
		SDL_WaitEvent(&event);
		if(event.type==SFM_REFRESH_EVENT){
			//------------------------------
			if(av_read_frame(pFormatCtx, packet)>=0){
				if(packet->stream_index==videoindex){
					ret = avcodec_decode_video2(pCodecCtx, pFrame, &got_picture, packet);
					if(ret < 0){
						printf("Decode Error.\n");
						return -1;
					}
					if(got_picture){
						sws_scale(img_convert_ctx, (const uint8_t* const*)pFrame->data, pFrame->linesize, 0, pCodecCtx->height, pFrameYUV->data, pFrameYUV->linesize);
						//SDL---------------------------
						SDL_UpdateTexture( sdlTexture, NULL, pFrameYUV->data[0], pFrameYUV->linesize[0] );  
						SDL_RenderClear( sdlRenderer );  
						//SDL_RenderCopy( sdlRenderer, sdlTexture, &sdlRect, &sdlRect );  
						SDL_RenderCopy( sdlRenderer, sdlTexture, NULL, NULL);  
						SDL_RenderPresent( sdlRenderer );  
						//SDL End-----------------------
					}
				}
				av_free_packet(packet);
			}else{
				//Exit Thread
				thread_exit=1;
			}
		}else if(event.type==SDL_QUIT){
			thread_exit=1;
		}else if(event.type==SFM_BREAK_EVENT){
			break;
		}

	}

	sws_freeContext(img_convert_ctx);

	SDL_Quit();
	//--------------
	av_frame_free(&pFrameYUV);
	av_frame_free(&pFrame);
	avcodec_close(pCodecCtx);
	avformat_close_input(&pFormatCtx);

	return 0;