I have a program which capture video from webcam, encode with ffmpeg, encoded packet then write to buffer. At the receiver side, read from buffer decode with ffmpeg and play.
Now I merge sender and receiver in one program for testing. It works fine with AV_CODEC_ID_MPEG1VIDEO, but when I change the ffmpeg codec to AV_CODEC_ID_H264, at the decoding progress, it shows error:
The whole program is here FYI, I made a loop to let the whole progress run twice.
What is the cause of the error, is there anything special for H264? Thanks in advance!
#include <math.h> extern "C" { #include <libavutil/opt.h> #include <libavcodec/avcodec.h> #include <libavutil/channel_layout.h> #include <libavutil/common.h> #include <libavutil/imgutils.h> #include <libavutil/mathematics.h> #include <libavutil/samplefmt.h> #include <libswscale/swscale.h> #include "v4l2.h" } #include "opencv2/highgui/highgui.hpp" #include <iostream> using namespace cv; using namespace std; #define INBUF_SIZE 4096 static uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; static AVCodec *codec; static AVCodecContext *c= NULL; static int ret, got_output; static int frame_count; static FILE *f; static AVPacket pkt; static AVFrame *frame; static AVFrame *frameDecode; static AVFrame *framergb; static uint8_t endcode[] = { 0, 0, 1, 0xb7 }; static AVPacket avpkt; int totalSize=0; #define SUBSITY 3 static int decode_write_frame(AVCodecContext *avctx, AVFrame *frame, int *frame_count, AVPacket *pkt, int last) { int len, got_frame; char buf[1024]; struct SwsContext *convert_ctx; Mat m; AVFrame dst; len = avcodec_decode_video2(avctx, frame, &got_frame, pkt); if (len < 0) { fprintf(stderr, "Error while decoding frame %d\n", *frame_count); return len; } if (got_frame) { printf("Saving %s frame %3d\n", last ? "last " : "", *frame_count); fflush(stdout); int w = avctx->width; int h = avctx->height; /*convert AVFrame to opencv Mat frame*/ m = cv::Mat(h, w, CV_8UC3); dst.data[0] = (uint8_t *)m.data; avpicture_fill( (AVPicture *)&dst, dst.data[0], PIX_FMT_BGR24, w, h); enum PixelFormat src_pixfmt = (enum PixelFormat)frame->format; enum PixelFormat dst_pixfmt = PIX_FMT_BGR24; convert_ctx = sws_getContext(w, h, src_pixfmt, w, h, dst_pixfmt, SWS_FAST_BILINEAR, NULL, NULL, NULL); if(convert_ctx == NULL) { fprintf(stderr, "Cannot initialize the conversion context!\n"); exit(1); } sws_scale(convert_ctx, frame->data, frame->linesize, 0, h, dst.data, dst.linesize); imshow("MyVideo", m); //video.write(m); waitKey(10); //wait next frame time (*frame_count)++; } if (pkt->data) { pkt->size -= len; pkt->data += len; } return 0; } static void video_decode_example(char *inbufout) { int bytes; uint8_t *buffer; av_init_packet(&avpkt); memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE); codec = avcodec_find_decoder(AV_CODEC_ID_H264); if (!codec) { fprintf(stderr, "Codec not found\n"); exit(1); } c = avcodec_alloc_context3(codec); if (!c) { fprintf(stderr, "Could not allocate video codec context\n"); exit(1); } if(codec->capabilities&CODEC_CAP_TRUNCATED) c->flags|= CODEC_FLAG_TRUNCATED; /* we do not send complete frames */ /* open it */ if (avcodec_open2(c, codec, NULL) < 0) { fprintf(stderr, "Could not open codec\n"); exit(1); } frameDecode = avcodec_alloc_frame(); if (!frameDecode) { fprintf(stderr, "Could not allocate video frame\n"); exit(1); } bytes=avpicture_get_size(PIX_FMT_RGB24, CAMER_WIDTH, CAMER_HEIGHT); buffer=(uint8_t *)av_malloc(bytes*sizeof(uint8_t)); avpicture_fill((AVPicture *)framergb, buffer, PIX_FMT_RGB24, CAMER_WIDTH, CAMER_HEIGHT);*/ frame_count = 0; namedWindow("MyVideo",CV_WINDOW_AUTOSIZE); //create a window called "MyVideo" int size1=0; for(;;) { memcpy(inbuf,inbufout+size1,INBUF_SIZE); size1+=INBUF_SIZE; if (size1>(totalSize-INBUF_SIZE)) break; avpkt.size=INBUF_SIZE; avpkt.data = inbuf; /*frame by frame process*/ while (avpkt.size > 0) if (decode_write_frame(c, frameDecode, &frame_count, &avpkt, 0) < 0) exit(1); } avpkt.data = NULL; avpkt.size = 0; decode_write_frame(c, frameDecode, &frame_count, &avpkt, 1); } static void init_video_encode(const char *filename, AVCodecID codec_id, int max_f) { printf("Encode video file %s\n", filename); /* find the mpeg1 video encoder */ codec = avcodec_find_encoder(codec_id); if (!codec) { fprintf(stderr, "Codec not found\n"); exit(1); } c = avcodec_alloc_context3(codec); if (!c) { fprintf(stderr, "Could not allocate video codec context\n"); exit(1); } /* put sample parameters */ c->bit_rate = 400000; /* resolution must be a multiple of two */ c->width = 640; c->height = 480; /* frames per second */ c->time_base= (AVRational){1,25}; c->gop_size = 10; /* emit one intra frame every ten frames */ c->max_b_frames=max_f; c->pix_fmt = AV_PIX_FMT_YUV420P; if(codec_id == AV_CODEC_ID_H264) av_opt_set(c->priv_data, "preset", "slow", 0); /* open it */ if (avcodec_open2(c, codec, NULL) < 0) { fprintf(stderr, "Could not open codec\n"); exit(1); } frame = avcodec_alloc_frame(); if (!frame) { fprintf(stderr, "Could not allocate video frame\n"); exit(1); } frame->format = c->pix_fmt; frame->width = c->width; frame->height = c->height; ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height, c->pix_fmt, 32); /* get the delayed frames */ if (ret < 0) { fprintf(stderr, "Could not allocate raw picture buffer\n"); exit(1); } printf("\n"); } int video_encode(int frameNo,char *inbufout) { static int count = 0; static int i = 0; /* encode 1 frame of video */ av_init_packet(&pkt); pkt.data = NULL; // packet data will be allocated by the encoder pkt.size = 0; //cout<<"\nBefore YUV\n"; if(count == 0) read_yuv420(frame->data[0]); count ++; if(count == SUBSITY) { count = 0; } frame->pts = i++; /* encode the image */ ret = avcodec_encode_video2(c, &pkt, frame, &got_output); if (ret < 0) { fprintf(stderr, "Error encoding frame\n"); return -1; } if (got_output) { printf("Write frame %3d (size=%5d)\n", i, pkt.size); memcpy(inbufout+totalSize,pkt.data,pkt.size); totalSize+=pkt.size; fwrite(pkt.data, 1, pkt.size, f); av_free_packet(&pkt); } return 0; } void cancle_encode(void) { fclose(f); avcodec_close(c); av_free(c); av_freep(&frame->data[0]); avcodec_free_frame(&frame); } int main(int argc, char **argv) { int i; char inbufout[25*50*(INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE)]; if(init_v4l2() < 0) { printf("can't open camera\n"); return 0; } /* register all the codecs */ avcodec_register_all(); for(int j=0;j<2;j++){ //init_video_encode("test.mpg", AV_CODEC_ID_MPEG1VIDEO, 15); init_video_encode("test.mpg", AV_CODEC_ID_H264, 15); //for(i = 0;i< 10*15;i++ ) { for(i = 0;i< 25*10;i++ ) { if(video_encode(i,inbufout) < 0) return 0; } cout<<"\n"<<totalSize<<"\n"<<endl; video_decode_example(inbufout); cancle_encode(); totalSize=0; } exit_v4l2(); return 0; } 
