/*
编译命令：arm-linux-gcc -o show2642 264showyuv2.c -I/usr/local/ffmpeg_arm/include/   -L/usr/local/ffmpeg_arm/lib/ -lswresample -lavformat -lavutil -lavcodec -lswscale -lx264   libSDL.a
*/
#include "stdio.h"
#include "stdlib.h"#include "libavformat/avformat.h"
#include "libavdevice/avdevice.h"
#include "libswresample/swresample.h"
#include "libavutil/opt.h"
#include "libavutil/channel_layout.h"
#include "libavutil/parseutils.h"
#include "libavutil/samplefmt.h"
#include "libavutil/fifo.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/dict.h"
#include "libavutil/mathematics.h"
#include "libavutil/pixdesc.h"
#include "libavutil/avstring.h"
#include "libavutil/imgutils.h"
#include "libavutil/timestamp.h"
#include "libavutil/bprint.h"
#include "libavutil/time.h"
#include "libavutil/threadmessage.h"
#include "/usr/local/ffmpeg_arm/include/SDL/SDL.h"#include "libavfilter/avcodec.h"
#include "libavcodec/avcodec.h"#if HAVE_SYS_RESOURCE_H
#include <sys/time.h>
#include <sys/types.h>
#include <sys/resource.h>
#elif HAVE_GETPROCESSTIMES
#include <windows.h>
#endif
#if HAVE_GETPROCESSMEMORYINFO
#include <windows.h>
#include <psapi.h>
#endif#if HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif#if HAVE_TERMIOS_H
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <termios.h>
#elif HAVE_KBHIT
#include <conio.h>
#endif#if HAVE_PTHREADS
#include <pthread.h>
#endif#include <time.h>#include "libavutil/avassert.h"#define MAX_LEN  1024 * 50此方法參考官网的样例
static void pgm_save(unsigned char *buf, int wrap, int xsize, int ysize,FILE *f)
{//  FILE *f;int i;// f = fopen(filename,"w");// fprintf(f, "P5\n%d %d\n%d\n", xsize, ysize, 255);for (i = 0; i < ysize; i++)fwrite(buf + i * wrap, 1, xsize, f);//  fclose(f);
}int main()
{//以下初始化h264解码库//avcodec_init();int w = 720;int h = 576,retu;SDL_Rect rect;av_register_all();AVFrame *pFrame_ = NULL;/* find the video encoder */AVCodec *videoCodec = avcodec_find_decoder(CODEC_ID_H264);//得到264的解码器类if(!videoCodec){printf("avcodec_find_decoder error\n");return -1;}AVCodecParserContext *avParserContext = av_parser_init(CODEC_ID_H264);//得到解析帧类。主要用于后面的帧头查找if(!avParserContext){printf("av_parser_init  error\n");return -1;}AVCodecContext *codec_ = avcodec_alloc_context3(videoCodec);//解码会话层if(!codec_){printf("avcodec_alloc_context3  error\n");return -1;}//初始化參数，以下的參数应该由详细的业务决定codec_->time_base.num = 1;codec_->frame_number = 1; //每包一个视频帧codec_->codec_type = AVMEDIA_TYPE_VIDEO;codec_->bit_rate = 0;codec_->time_base.den = 25;//帧率codec_->width = 720;//视频宽codec_->height = 576;//视频高if(avcodec_open2(codec_, videoCodec, NULL) >= 0)//打开解码器{pFrame_ = avcodec_alloc_frame();// Allocate video frame    成功打开解码器后， 此时能够分配帧内存， 当然你也能够在后面每次都分配、释放， 在此我省功夫， 仅仅在開始分配一次if (!pFrame_) {fprintf(stderr, "Could not allocate video frame\n");exit(1);}}else{printf("avcodec_open2 error\n");return -1;}AVPacket packet = {0};int dwBufsize = 10;int frameFinished = dwBufsize;//这个是随便填入数字，没什么作用av_init_packet(&packet);packet.data = NULL;//这里填入一个指向完整H264数据帧的指针packet.size = 0;//这个填入H264数据帧的大小FILE *myH264 = fopen("1.264", "rb");//解码的文件264if(myH264 == NULL){perror("cant open 264 file\n");return -1;}FILE *yuvfile = fopen("my264.yuv", "wb");//成功解码后保存成的YUV文件， 能够用YUV工具打开浏览if(yuvfile == NULL){perror("cant open YUV file\n");return -1;}int readFileLen = 1;char readBuf[MAX_LEN];unsigned char *parseBuf = malloc(20*MAX_LEN);//这个地方浪费了我一个下午时间， 当时我用的是栈内存。即unsigned char parseBuf[20*MAX_LEN]。 结果执行程序一直报错， 此处须要用堆内存才干正常解码int  parseBufLen = 0;int frameCount = 0;printf("begin...\n");printf("readBuf address  is %x\n", readBuf);
/SDL initSDL_Surface* hello = NULL;SDL_Surface* screen = NULL;//Start SDL// SDL_Init( SDL_INIT_EVERYTHING );SDL_Init(SDL_INIT_VIDEO);//Set up screenscreen = SDL_SetVideoMode( 1024, 768, 32, SDL_SWSURFACE );SDL_Overlay* overlay = SDL_CreateYUVOverlay(w, h, SDL_YV12_OVERLAY, screen);SDL_LockSurface(screen);SDL_LockYUVOverlay(overlay);
//while(readFileLen > 0)//開始解码工作{//printf("begin...\n");readFileLen = fread(readBuf, 1, sizeof(readBuf), myH264);//首先从文件中读出数据if(readFileLen <= 0){printf("read over\n");break;}else{int handleLen = 0;int handleFileLen = readFileLen;while(handleFileLen > 0){int nLength = av_parser_parse2(avParserContext, codec_, &parseBuf, &parseBufLen, readBuf + handleLen, handleFileLen, 0, 0, 0);//查找264帧头handleFileLen -= nLength;handleLen += nLength;if(parseBufLen <= 0)//当parseBufLen大于0时，说明查找到了帧头{continue;}packet.size = parseBufLen;//将查找到的帧长度送入packet.data = parseBuf;//将查找到的帧内存送入if(frameCount>100)break;//printf("parseBuf address is %x\n", parseBuf);while(packet.size > 0){//以下開始真正的解码int decodeLen = avcodec_decode_video2(codec_, pFrame_, &frameFinished, &packet);if(decodeLen < 0)break;packet.size -= decodeLen;packet.data += decodeLen;if(frameFinished > 0)//成功解码{int picSize = codec_->height * codec_->width;//int newSize = picSize * 1.5;//申请内存//unsigned char *buf = malloc(newSize);int height = pFrame_->height;int width = pFrame_->width;//printf("OK, get data\n");//printf("Frame height is %d\n", height);//printf("Frame width is %d\n", width);frameCount ++;printf("Frame count is %d\n", frameCount);pgm_save(pFrame_->data[0], pFrame_->linesize[0],//保存Ycodec_->width, codec_->height, yuvfile);pgm_save(pFrame_->data[1], pFrame_->linesize[1],//保存Ucodec_->width/2, codec_->height/2, yuvfile);pgm_save(pFrame_->data[2], pFrame_->linesize[2],//保存Vcodec_->width/2, codec_->height/2, yuvfile);///有了YUV数据。 后面能够用FFMPEG提供的转换方法。将其转成RGB数据，进行兴许的显示或其他的图像处理工作sdlint i;for(i=0;i<576;i++){//fwrite(buf + i * wrap, 1, xsize, f);memcpy(overlay->pixels[0]+i*720, pFrame_->data[0]+i*pFrame_->linesize[0], 720);                               }for(i=0;i<288;i++){memcpy(overlay->pixels[2]+i*360, pFrame_->data[1]+i*pFrame_->linesize[1], 360);memcpy(overlay->pixels[1]+i*360, pFrame_->data[2]+i*pFrame_->linesize[2], 360);                                                                      }SDL_UnlockYUVOverlay(overlay);SDL_UnlockSurface(screen);rect.w = w;rect.h = h;rect.x = rect.y = 0;SDL_DisplayYUVOverlay(overlay, &rect);//sdl//SDL_Delay(40);}elseprintf("failed to decodec\n");}}}}//释放工作avcodec_close(codec_);av_free(codec_);av_free_packet(&packet);av_frame_free(&pFrame_);//SDLSDL_FreeYUVOverlay(overlay);SDL_FreeSurface(screen);//Quit SDLSDL_Quit();fclose(yuvfile);fclose(myH264);}