#define __STDC_CONSTANT_MACROS #include <string.h> extern "C" { #include "libavutil/avutil.h" #include "libavdevice/avdevice.h" #include "libavformat/avformat.h" #include "libavcodec/avcodec.h" #include "libswresample/swresample.h" #include "libavdevice/avdevice.h" } #define WIDTH 640 #define HEIGHT 480 static AVFormatContext* open_dev(){ int ret = 0; char errors[1024] = { 0, }; //ctx AVFormatContext *fmt_ctx = NULL; AVDictionary *options = NULL; //[[video device]:[audio device]] const char *device_name = "/dev/video0"; av_dict_set(&options, "video_size", "640x480",0); //get format AVInputFormat *iformat = av_find_input_format("video4linux2"); //open device if ((ret = avformat_open_input(&fmt_ctx, device_name, iformat, &options)) < 0){ av_strerror(ret, errors, 1024); fprintf(stderr, "Failed to open audio device, [%d]%s\n", ret, errors); return NULL; } return fmt_ctx; } void open_encodec(int width, int height, AVCodecContext ** enc_ctx) { AVCodec * codec = avcodec_find_encoder_by_name("libx264"); if(codec == NULL) { av_log(NULL, AV_LOG_INFO, "Codec libx264 not found!\n"); return; } *enc_ctx = avcodec_alloc_context3(codec); if(enc_ctx == NULL) { av_log(NULL, AV_LOG_INFO, "alloc context3 failed!\n"); return; } //sps pps (*enc_ctx)->profile = FF_PROFILE_H264_HIGH_444; (*enc_ctx)->level = 50;//level 5.0 version //resolution (*enc_ctx)->width = width; (*enc_ctx)->height = height; //GOP (*enc_ctx)->gop_size = 250; (*enc_ctx)->keyint_min = 25; (*enc_ctx)->max_b_frames = 3; (*enc_ctx)->has_b_frames = 1; (*enc_ctx)->refs = 3; (*enc_ctx)->pix_fmt = AV_PIX_FMT_YUV420P; (*enc_ctx)->bit_rate = 60000000;// 6000kbps (*enc_ctx)->time_base = (AVRational){1,30}; (*enc_ctx)->framerate = (AVRational){30,1}; int ret = avcodec_open2((*enc_ctx), codec, NULL); if(ret < 0) { av_log(NULL, AV_LOG_INFO, "avcodec_open2 failed!\n"); return; } } AVFrame* create_frame(int width, int height) { AVFrame *frame = av_frame_alloc(); if(frame == NULL) { av_log(NULL, AV_LOG_INFO, "av_frame_alloc failed!\n"); return NULL; } frame->width = width; frame->height = height; frame->format = AV_PIX_FMT_YUV420P; int ret = av_frame_get_buffer(frame, 32); if(ret < 0) { av_log(NULL, AV_LOG_INFO, "av_frame_get_buffer failed!\n"); return NULL; } return frame; } static void encode(AVCodecContext *ctx, AVFrame *frame, AVPacket *newpkt, FILE * outfile) { #if 0 int ret = avcodec_send_frame(ctx, frame); if(ret < 0) { av_log(NULL, AV_LOG_INFO, "avcodec_send_frame failed!\n"); exit(-1); } while(ret >= 0) { ret = avcodec_receive_packet(ctx,newpkt); if(ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) { //av_log(NULL, AV_LOG_INFO, "avcodec_receive_packet no more data!\n"); return; } else if(ret < 0) { av_log(NULL, AV_LOG_INFO, "avcodec_receive_packet failed!\n"); exit(-1); } fwrite(newpkt->data, 1, newpkt->size, outfile); av_packet_unref(newpkt); } #endif } void rec_video() { //context AVFormatContext *fmt_ctx = NULL; //set log level av_log_set_level(AV_LOG_DEBUG); //register audio device avdevice_register_all(); //create file const char *out = "/home/lili/Videos/video.yuv"; FILE *outfile = fopen(out, "wb+"); if (!outfile) { printf("Error, Failed to open file!\n"); return; } AVCodecContext *codec_ctx = NULL; open_encodec(WIDTH, HEIGHT, &codec_ctx); //编码的输入数据 AVFrame* avframe = create_frame(WIDTH, HEIGHT); //创建编码后输出的数据 AVPacket* newpkt = av_packet_alloc(); if (!newpkt){ printf("Error, av_packet_alloc!\n"); return; } //打开设备 fmt_ctx = open_dev(); if (!fmt_ctx){ printf("Error, Failed to open device!\n"); return; } AVPacket pkt; int ret = -1, count = 1; const char *encode_file_path = "/home/lili/Videos/video.h264"; FILE *encode_file = fopen(encode_file_path, "wb+"); if (!encode_file) { printf("Error, Failed to open file!\n"); return; } int base = 0;int got_output = 0; while((ret = av_read_frame(fmt_ctx, &pkt)) == 0 && count++ < 200) { av_log(NULL, AV_LOG_INFO, "packet size is %d\n", pkt.size); #define FORMAT_YUYV #ifdef FORMAT_YUV //ffplay -s 640x480 -pixel_format yuyv422 ~/Videos/video.yuv fwrite(pkt.data, 1, pkt.size, outfile);//yuyv422 format fflush(outfile); #else /* Y U Y V Y U Y V Y U Y V Y U Y V Y U Y V Y U Y V Y U Y V Y U Y V - yuyv422 - Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y U U U U U U V V V V V V U V U V U V V U V U V U V V V V V V U U U U U U U V U V U V V U V U V U - I420 - - YV12 - - NV12 - - NV21 - */ //ffplay -video_size 640x480 -pixel_format yuv420p ~/Videos/video.yuv int len = WIDTH * HEIGHT; for(int i = 0;i < len; i++){ avframe->data[0][i] = pkt.data[i*2];//Y } //yuyv 序列为YU YV YU YV，一个yuv422帧的长度 width * height * 2 个字节 //yuyv --- >yuv420p丢弃偶数行 u v int cnt = 0; for(int i = 0; i < HEIGHT; i += 2) { for(int j = 0; j < WIDTH/2; j++) { avframe->data[1][cnt] = pkt.data[i * WIDTH * 2 + j * 4 + 1];//Cb avframe->data[2][cnt++] = pkt.data[i * WIDTH * 2 + j * 4 + 3];//Cr } } fwrite(avframe->data[0], 1, WIDTH * HEIGHT, outfile); fwrite(avframe->data[1], 1, WIDTH * HEIGHT/4, outfile); fwrite(avframe->data[2], 1, WIDTH * HEIGHT/4, outfile); fflush(outfile); //important!!! avframe->pts = base++; //encode(codec_ctx, avframe, newpkt, encode_file); ret = avcodec_encode_video2(codec_ctx, newpkt, avframe, &got_output); if (ret < 0) { fprintf(stderr, "Error encoding frame\n"); exit(1); } if (got_output) { printf("Write frame (size=%5d)\n", newpkt->size); fwrite(newpkt->data, 1, newpkt->size, encode_file); fflush(encode_file); av_packet_unref(newpkt); } #endif } /* get the delayed frames */ for (got_output = 1; got_output;) { fflush(stdout); ret = avcodec_encode_video2(codec_ctx, newpkt, NULL, &got_output); if (ret < 0) { fprintf(stderr, "Error encoding frame\n"); exit(1); } if (got_output) { printf("Write frame (size=%5d)\n", newpkt->size); fwrite(newpkt->data, 1, newpkt->size, encode_file); av_packet_unref(newpkt); } } fclose(outfile); fclose(encode_file); av_log(NULL, AV_LOG_DEBUG, "finish!\n"); return; } int main() { rec_video(); return 0; }
