致敬雷神【最简单的基于FFMPEG的视频编码器（YUV编码为H.264）】最新ffmpeg编译

最近开始学习ffmpeg.学到 雷神的

最简单的基于FFMPEG的视频编码器（YUV编码为H.264）

https://blog.youkuaiyun.com/leixiaohua1020/article/details/25430425

发觉2020.5月的版本编译使用时已经运行不正确。后来修改了一点东西才成功yuvb编码出mp4.

首先是yuv文件。我没下他对应的工程文件，用的是640x360_yuv420p.yuv

对应要修改下

int in_w=640,in_h=360;                              //Input data's width and height

   int framenum=56;      

不然编码肯定会错的。

 

然后是原来代码运行会提示参数未指定

我只设置了格式和宽高，就能成功编码出mp4了。

    pFrame->format=    AV_PIX_FMT_YUV420P;
    pFrame->width = in_w;  
    pFrame->height = in_h;

 

运行

目录下看有个ds.mp4  111 KB (113,923 字节)

播放器打开能正常播放。

至于提示api已经不建议。暂时我就不管了。才学习。先把旧的搞懂。

 

把const char* out_file = "ds.h264";  运行，也能成功生成ds.h264. 正常播放。

 

下面是完整代码

#include "stdafx.h"
#include <stdio.h>
 
#define __STDC_CONSTANT_MACROS
 
#ifdef _WIN32
//Windows
extern "C"
{
#include "libavutil/opt.h"
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
};
#else
//Linux...
#ifdef __cplusplus
extern "C"
{
#endif
#include <libavutil/opt.h>
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#ifdef __cplusplus
};
#endif
#endif
 
 
int flush_encoder(AVFormatContext *fmt_ctx,unsigned int stream_index){
	int ret;
	int got_frame;
	AVPacket enc_pkt;
	if (!(fmt_ctx->streams[stream_index]->codec->codec->capabilities &
		AV_CODEC_CAP_DELAY))
		return 0;
	while (1) {
		enc_pkt.data = NULL;
		enc_pkt.size = 0;
		av_init_packet(&enc_pkt);
		ret = avcodec_encode_video2 (fmt_ctx->streams[stream_index]->codec, &enc_pkt,
			NULL, &got_frame);
		av_frame_free(NULL);
		if (ret < 0)
			break;
		if (!got_frame){
			ret=0;
			break;
		}
		printf("Flush Encoder: Succeed to encode 1 frame!\tsize:%5d\n",enc_pkt.size);
		/* mux encoded frame */
		ret = av_write_frame(fmt_ctx, &enc_pkt);
		if (ret < 0)
			break;
	}
	return ret;
}
 
int main(int argc, char* argv[])
{
	AVFormatContext* pFormatCtx;
	AVOutputFormat* fmt;
	AVStream* video_st;
	AVCodecContext* pCodecCtx;
	AVCodec* pCodec;
	AVPacket pkt;
	uint8_t* picture_buf;
	AVFrame* pFrame;
	int picture_size;
	int y_size;
	int framecnt=0;
	//FILE *in_file = fopen("src01_480x272.yuv", "rb");	//Input raw YUV data 
	FILE *in_file = fopen("640x360_yuv420p.yuv", "rb");   //Input raw YUV data
	int in_w=640,in_h=360;                              //Input data's width and height
	int framenum=56;                                   //Frames to encode
	//const char* out_file = "src01.h264";              //Output Filepath 
	//const char* out_file = "src01.ts";
	//const char* out_file = "src01.hevc";
	const char* out_file = "ds.h264";
 
	av_register_all();
	//Method1.
	pFormatCtx = avformat_alloc_context();
	//Guess Format
	fmt = av_guess_format(NULL, out_file, NULL);
	pFormatCtx->oformat = fmt;
	
	//Method 2.
	//avformat_alloc_output_context2(&pFormatCtx, NULL, NULL, out_file);
	//fmt = pFormatCtx->oformat;
 
 
	//Open output URL
	if (avio_open(&pFormatCtx->pb,out_file, AVIO_FLAG_READ_WRITE) < 0){
		printf("Failed to open output file! \n");
		return -1;
	}
 
	video_st = avformat_new_stream(pFormatCtx, 0);
	//video_st->time_base.num = 1; 
	//video_st->time_base.den = 25;  
 
	if (video_st==NULL){
		return -1;
	}
	//Param that must set
	pCodecCtx = video_st->codec;
	//pCodecCtx->codec_id =AV_CODEC_ID_HEVC;
	pCodecCtx->codec_id = fmt->video_codec;
	pCodecCtx->codec_type = AVMEDIA_TYPE_VIDEO;
	pCodecCtx->pix_fmt = AV_PIX_FMT_YUV420P;
	pCodecCtx->width = in_w;  
	pCodecCtx->height = in_h;
	pCodecCtx->bit_rate = 400000;  
	pCodecCtx->gop_size=250;
 
	pCodecCtx->time_base.num = 1;  
	pCodecCtx->time_base.den = 25;  
 
	//H264
	//pCodecCtx->me_range = 16;
	//pCodecCtx->max_qdiff = 4;
	//pCodecCtx->qcompress = 0.6;
	pCodecCtx->qmin = 10;
	pCodecCtx->qmax = 51;
 
	//Optional Param
	pCodecCtx->max_b_frames=3;
 
	// Set Option
	AVDictionary *param = 0;
	//H.264
	if(pCodecCtx->codec_id == AV_CODEC_ID_H264) {
		av_dict_set(&param, "preset", "slow", 0);
		av_dict_set(&param, "tune", "zerolatency", 0);
		//av_dict_set(param, "profile", "main", 0);
	}
	//H.265
	if(pCodecCtx->codec_id == AV_CODEC_ID_H265){
		av_dict_set(&param, "preset", "ultrafast", 0);
		av_dict_set(&param, "tune", "zero-latency", 0);
	}
 
	//Show some Information
	av_dump_format(pFormatCtx, 0, out_file, 1);
 
	pCodec = avcodec_find_encoder(pCodecCtx->codec_id);
	if (!pCodec){
		printf("Can not find encoder! \n");
		return -1;
	}
	if (avcodec_open2(pCodecCtx, pCodec,&param) < 0){
		printf("Failed to open encoder! \n");
		return -1;
	}
 
 
	pFrame = av_frame_alloc();
	picture_size = avpicture_get_size(pCodecCtx->pix_fmt, pCodecCtx->width, pCodecCtx->height);
	picture_buf = (uint8_t *)av_malloc(picture_size);
	avpicture_fill((AVPicture *)pFrame, picture_buf, pCodecCtx->pix_fmt, pCodecCtx->width, pCodecCtx->height);
 
	pFrame->format=	AV_PIX_FMT_YUV420P;
	pFrame->width = in_w;  
	pFrame->height = in_h;

	//Write File Header
	avformat_write_header(pFormatCtx,NULL);
 
	av_new_packet(&pkt,picture_size);
 
	y_size = pCodecCtx->width * pCodecCtx->height;
 
	for (int i=0; i<framenum; i++){
		//Read raw YUV data
		if (fread(picture_buf, 1, y_size*3/2, in_file) <= 0){
			printf("Failed to read raw data! \n");
			return -1;
		}else if(feof(in_file)){
			break;
		}
		pFrame->data[0] = picture_buf;              // Y
		pFrame->data[1] = picture_buf+ y_size;      // U 
		pFrame->data[2] = picture_buf+ y_size*5/4;  // V
		//PTS
		//pFrame->pts=i;
		pFrame->pts=i*(video_st->time_base.den)/((video_st->time_base.num)*25);
		int got_picture=0;
		//Encode
		int ret = avcodec_encode_video2(pCodecCtx, &pkt,pFrame, &got_picture);
		if(ret < 0){
			printf("Failed to encode! \n");
			return -1;
		}
		if (got_picture==1){
			printf("Succeed to encode frame: %5d\tsize:%5d\n",framecnt,pkt.size);
			framecnt++;
			pkt.stream_index = video_st->index;
			ret = av_write_frame(pFormatCtx, &pkt);
			av_free_packet(&pkt);
		}
	}
	//Flush Encoder
	int ret = flush_encoder(pFormatCtx,0);
	if (ret < 0) {
		printf("Flushing encoder failed\n");
		return -1;
	}
 
	//Write file trailer
	av_write_trailer(pFormatCtx);
 
	//Clean
	if (video_st){
		avcodec_close(video_st->codec);
		av_free(pFrame);
		av_free(picture_buf);
	}
	avio_close(pFormatCtx->pb);
	avformat_free_context(pFormatCtx);
 
	fclose(in_file);
 
	return 0;
}

好像有人指出过雷神当时的代码忘了释放编码器什么的，我也不管了。以后自然就知道了