https://blog.csdn.net/bixinwei22/article/details/94454258
首先看下效果
左上角的实时当前时间，纯c完成。下面的是hello ffmpeg字样是avfilter的drawtext实现。
动态时间水印，其实ffmpeg有命令可以实现，不过我在windows下发现用不了，而且转换出来的图片会质量变差。
所以想着自己用C去实现。上面的2019-07-02 16:30:46 这些是在android下，用canvas drawtext每一个字符，然后生产对应的
bitmap,然后从bitmap里面提取出rgb数据，然后转出来yuv的y数据,因为我们只需要黑白两种颜色，所以使用y足够了。
avfilter我的博客还没有讲过，以后有时间再讲。
下面上代码
#include <stdio.h> #include <stdlib.h> #include <string> #include <iostream> extern "C" { #include "libavcodec/avcodec.h" #include "libavformat/avformat.h" #include "libswscale/swscale.h" #include "libswresample/swresample.h" #include "libavutil/time.h" #include "libswresample/swresample.h" #include "libavutil/audio_fifo.h" #include "libavutil/avutil.h" #include "libavutil/opt.h" #include "libavfilter/avfilter.h" #include "libavfilter/avfiltergraph.h" #include "libavfilter/buffersink.h" #include "libavfilter/buffersrc.h" } using namespace std; void Init() { av_register_all(); avfilter_register_all(); avformat_network_init(); //av_log_set_level(AV_LOG_ERROR); } AVFilterGraph * filter_graph = nullptr; AVFilterContext *buffersink_ctx = nullptr;; AVFilterContext *buffersrc_ctx = nullptr;; AVFormatContext * ifmt_ctx = NULL; AVFormatContext * ofmt_ctx = NULL; AVStream *ist_v = NULL; AVCodecContext * ic_ctx_v = NULL; int iv_index = -1; AVStream *ost_v = NULL; AVCodecContext * oc_ctx_v = NULL; char *mNumArrays; int num_width = 17; int num_height = 23; int off_x = 18; int off_y = 18; int patternLen; int getIndex(char c) { if (c >= '0' && c <= '9') return c - '0'; else if (c == '-') return 10; else if (c == ' ') return 11; else if (c == ':') return 12; return 11; } void initWatemake() { char pattern[] = "yyyy-MM-dd HH:mm:ss"; patternLen = sizeof(pattern); mNumArrays = (char*)malloc(num_width * num_height*patternLen); char NUM_0[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,1,1,0,0,1,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,1,1,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,1,1,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,1,1,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,1,1,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,0,0,0,0,1,1,1,1,1,1,0,0,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,0,0,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_1[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_2[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,1,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,1,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,1,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_3[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_4[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,1,1,1,1,0,0,1,1,1,1,0,0,0,0,0,0,0,1,1,1,1,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_5[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_6[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_7[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_8[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_9[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_SPACE[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_COLON[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; char NUM_LINE[] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; int size = num_width * num_height; memcpy(mNumArrays, NUM_0, size); memcpy(mNumArrays + size * 1, NUM_1, size); memcpy(mNumArrays + size * 2, NUM_2, size); memcpy(mNumArrays + size * 3, NUM_3, size); memcpy(mNumArrays + size * 4, NUM_4, size); memcpy(mNumArrays + size * 5, NUM_5, size); memcpy(mNumArrays + size * 6, NUM_6, size); memcpy(mNumArrays + size * 7, NUM_7, size); memcpy(mNumArrays + size * 8, NUM_8, size); memcpy(mNumArrays + size * 9, NUM_9, size); memcpy(mNumArrays + size * 10, NUM_LINE, size); memcpy(mNumArrays + size * 11, NUM_SPACE, size); memcpy(mNumArrays + size * 12, NUM_COLON, size); } int InitDecodeCodec(AVCodecID codecId) { auto codec = avcodec_find_decoder(codecId); if (!codec) { return -1; } if (codec->capabilities & CODEC_CAP_TRUNCATED) ic_ctx_v->flags |= CODEC_FLAG_TRUNCATED; int ret = avcodec_open2(ic_ctx_v, codec, NULL); if (ret < 0) { cout << "open input vcodec failed" << endl; } return ret; } int OpenInput(char *filename) { ifmt_ctx = avformat_alloc_context(); int ret = avformat_open_input(&ifmt_ctx, filename, NULL, NULL); if (ret < 0) { return ret; } ret = avformat_find_stream_info(ifmt_ctx, NULL); av_dump_format(ifmt_ctx, 0, filename, 0); if (ret >= 0) { cout << "open input stream successfully" << endl; } for (int i = 0; i < ifmt_ctx->nb_streams; i++) { if (ifmt_ctx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) { iv_index = i; ist_v = ifmt_ctx->streams[i]; ic_ctx_v = ist_v->codec; } } InitDecodeCodec(ic_ctx_v->codec_id); return ret; } int InitEncoderCodec(int dstW, int dstH) { AVCodec * pH264Codec = avcodec_find_encoder(AV_CODEC_ID_H264); if (NULL == pH264Codec) { cout << "find output vcodec failed" << endl; return -1; } oc_ctx_v = avcodec_alloc_context3(pH264Codec); oc_ctx_v->gop_size = ic_ctx_v->gop_size; oc_ctx_v->has_b_frames = 0; oc_ctx_v->max_b_frames = 0; oc_ctx_v->codec_id = pH264Codec->id; oc_ctx_v->time_base.num = ic_ctx_v->time_base.num;; oc_ctx_v->time_base.den = ic_ctx_v->time_base.den;; oc_ctx_v->pix_fmt = *pH264Codec->pix_fmts; oc_ctx_v->width = dstW; oc_ctx_v->height = dstH; oc_ctx_v->codec_tag = 0; // some formats want stream headers to be separate if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER) oc_ctx_v->flags |= CODEC_FLAG_GLOBAL_HEADER; int ret = avcodec_open2(oc_ctx_v, pH264Codec, NULL); if (ret < 0) { cout << "open output vcodec failed" << endl; return ret; } ost_v = avformat_new_stream(ofmt_ctx, oc_ctx_v->codec); ost_v->codec = oc_ctx_v; return 1; } int OpenOutput(char *fileName) { int ret = 0; ret = avformat_alloc_output_context2(&ofmt_ctx, NULL, "flv", fileName); if (ret < 0) { goto Error; } ret = avio_open2(&ofmt_ctx->pb, fileName, AVIO_FLAG_READ_WRITE, NULL, NULL); if (ret < 0) { goto Error; } //InitEncoderCodec(640,480); InitEncoderCodec(ic_ctx_v->width, ic_ctx_v->height); //InitEncoderCodec(ic_ctx_v->width*1/2, ic_ctx_v->height*1/2); av_dump_format(ofmt_ctx, 0, fileName, 1); ret = avformat_write_header(ofmt_ctx, NULL); if (ret < 0) { goto Error; } if (ret >= 0) cout << "open output stream successfully" << endl; return ret; Error: if (ofmt_ctx) { avformat_close_input(&ofmt_ctx); } return ret; } void CloseInput() { if (ifmt_ctx) { avformat_close_input(&ifmt_ctx); } } void CloseOutput() { if (ofmt_ctx) { avcodec_close(oc_ctx_v); avformat_close_input(&ofmt_ctx); } } int InitFilter(AVCodecContext * codecContext) { char args[512]; int ret = 0; AVFilter *buffersrc = avfilter_get_by_name("buffer"); AVFilter *buffersink = avfilter_get_by_name("buffersink"); AVFilterInOut *outputs = avfilter_inout_alloc(); AVFilterInOut *inputs = avfilter_inout_alloc(); //string filters_descr = "scale=640:480"; //string filters_descr = "movie=my_logo.png[wm];[in][wm]overlay=5:5[out]"; //string filters_descr = "drawtext=fontfile=arial.ttf:fontcolor=white:fontsize=36:text='Lei Xiaohua':x=20:y=20"; //string filters_descr = "drawbox=x=100:y=100:w=100:h=100:color=pink@0.5";//画正方形 //string filters_descr = "crop=1/2*in_w:1/2*in_h:0:0"; string filters_descr = "drawtext=fontfile=FreeSerif1.ttf:fontcolor=white:fontsize=36:text='Hello FFmpeg':x=18:y=200"; //const char *filter_descr = "lutyuv='u=128:v=128'"; //const char *filter_descr = "boxblur"; //const char *filter_descr = "hflip"; //const char *filter_descr = "hue='h=60:s=-3'"; //const char *filter_descr = "crop=2/3*in_w:2/3*in_h"; //const char *filter_descr = "drawbox=x=100:y=100:w=100:h=100:color=pink@0.5"; //const char *filter_descr = "drawtext=fontfile=arial.ttf:fontcolor=green:fontsize=30:text='Lei Xiaohua'"; enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE }; filter_graph = avfilter_graph_alloc(); if (!outputs || !inputs || !filter_graph) { ret = AVERROR(ENOMEM); goto end; } /* buffer video source: the decoded frames from the decoder will be inserted here. */ sprintf_s(args, sizeof(args), "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d", codecContext->width, codecContext->height, codecContext->pix_fmt, codecContext->time_base.num, codecContext->time_base.den, codecContext->sample_aspect_ratio.num, codecContext->sample_aspect_ratio.den); ret = avfilter_graph_create_filter(&buffersrc_ctx, buffersrc, "in", args, NULL, filter_graph); if (ret < 0) { printf("Cannot create buffer source\n"); goto end; } /* buffer video sink: to terminate the filter chain. */ ret = avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out", NULL, NULL, filter_graph); if (ret < 0) { printf("Cannot create buffer sink\n"); goto end; } ret = av_opt_set_int_list(buffersink_ctx, "pix_fmts", pix_fmts, AV_PIX_FMT_YUV420P, AV_OPT_SEARCH_CHILDREN); if (ret < 0) { printf("Cannot set output pixel format\n"); goto end; } /* Endpoints for the filter graph. */ outputs->name = av_strdup("in"); outputs->filter_ctx = buffersrc_ctx; outputs->pad_idx = 0; outputs->next = NULL; inputs->name = av_strdup("out"); inputs->filter_ctx = buffersink_ctx; inputs->pad_idx = 0; inputs->next = NULL; if ((ret = avfilter_graph_parse_ptr(filter_graph, filters_descr.c_str(), &inputs, &outputs, NULL)) < 0) { printf("avfilter_graph_parse_ptr failed\n"); goto end; } if ((ret = avfilter_graph_config(filter_graph, NULL)) < 0) { printf("avfilter_graph_config failed\n"); goto end; } return ret; end: avfilter_inout_free(&inputs); avfilter_inout_free(&outputs); return ret; } void addwatemake(char* y,int count,time_t *t,int bigwidth) { struct tm *tm_now = localtime(t); if (count % 25 == 0) { (*t) +=1; } char tmp[64] = { 0 }; strftime(tmp, sizeof(tmp), "%Y-%m-%d %X", tm_now); char* tmdate = (char*)malloc(patternLen);//2019-07-01 10:17:23 memset(tmdate, 0, patternLen); memcpy(tmdate, tmp, patternLen - 1); int size = num_width * num_height; char *start = y + off_y * bigwidth + off_x; for (int i = 0; i < patternLen; i++) { int index = getIndex(*(tmdate + i)); char *num = mNumArrays + size * index; for (int j = 0; j < num_height; j++) { char *destIndex = start + i * num_width; for (int k = 0; k < num_width; k++) { if (*(num + j * num_width + k) == 1) { *(destIndex + j * bigwidth + k) = 235;//水印文字颜色，235为白色，16为黑色 } } } } free(tmdate); } int main(int argc, char* argv[]) { int ret; string fileInput = "love_360p.flv"; string fileOutput = "out.flv"; Init(); if (OpenInput((char *)fileInput.c_str()) < 0) { cout << "Open file Input failed!" << endl; return 0; } if (OpenOutput((char *)fileOutput.c_str()) < 0) { cout << "Open file Output failed!" << endl; return 0; } ret = InitFilter(ic_ctx_v); AVFrame* filterFrame = av_frame_alloc(); AVPacket* packet = (AVPacket*)av_malloc(sizeof(AVPacket)); av_init_packet(packet); packet->data = NULL; packet->size = 0; int packetCount = 0; initWatemake(); time_t t = time(0); int count = 0; char* testdata = (char*)malloc(640 * 360); memset(testdata, 0, 640 * 360); AVFrame* pSrcFrame2 = av_frame_alloc(); /*uint8_t *video_data_buffer = NULL; video_data_buffer = new uint8_t[avpicture_get_size(ic_ctx_v->pix_fmt, ic_ctx_v->width, ic_ctx_v->height)]; avpicture_fill((AVPicture *)pSrcFrame2, video_data_buffer, ic_ctx_v->pix_fmt, ic_ctx_v->width, ic_ctx_v->height); */ while (1) { ret = av_read_frame(ifmt_ctx, packet); if (ret < 0) { break; } if (packet->stream_index != iv_index) { continue; } int got_frame = 0; AVFrame* pSrcFrame = av_frame_alloc(); ret = avcodec_decode_video2(ic_ctx_v, pSrcFrame, &got_frame, packet); if (ret < 0) { printf("Error decoding video\n"); break; } if (got_frame) { count++; memcpy(testdata, pSrcFrame->data[0], 640 * 360); addwatemake(testdata, count, &t, ic_ctx_v->width); av_frame_ref(pSrcFrame2, pSrcFrame); memcpy(pSrcFrame2->data[0], testdata, 640 * 360); pSrcFrame2->pts = av_frame_get_best_effort_timestamp(pSrcFrame); /* push the decoded frame into the filtergraph */ if (av_buffersrc_add_frame_flags(buffersrc_ctx, pSrcFrame2, AV_BUFFERSRC_FLAG_KEEP_REF) < 0) { av_log(NULL, AV_LOG_ERROR, "Error while feeding the filtergraph\n"); break; } /* pull filtered frames from the filtergraph */ while (1) { ret = av_buffersink_get_frame(buffersink_ctx, filterFrame); if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) break; if (ret < 0) goto end; AVPacket *opkt = (AVPacket *)av_malloc(sizeof(AVPacket)); av_init_packet(opkt); opkt->data = NULL; opkt->size = 0; int got_output; filterFrame->pict_type = AV_PICTURE_TYPE_NONE; ret = avcodec_encode_video2(oc_ctx_v, opkt, filterFrame, &got_output); if (ret >= 0 && got_output) { packetCount += 40; opkt->pts = opkt->dts = packetCount; int ret = av_write_frame(ofmt_ctx, opkt); } av_free_packet(opkt); av_frame_unref(filterFrame); } } av_frame_free(&pSrcFrame); } free(testdata); end: CloseInput(); CloseOutput(); cout << "end!" << endl; return 0; }
代码中640，360是我使用的测试视频的宽高，大家可以自己修改，我就懒得改了。
主要讲一个坑点，就是decode出来的frame不要修改它的data，自己去复制一个使用。这就是为什么程序中引入了pSrcFrame2,而不是直接用pSrcFrame。
代码自己琢磨吧，我就不吧啦吧啦了，不懂的留言
———————————————— 版权声明：本文为博主「bixinwei」的原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接及本声明。 原文链接：https://blog.csdn.net/bixinwei22/article/details/94454258
