ffmpeg设置屏幕分辨率

函数

int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags);

 录制视频的大小（宽高）

av_dict_set(&dict, "video_size", video_size, 0);    

获取video_size（分辨率格式例如1980×1440），可自定义

av_dict_set(&dict, "video_size", 1980×1440, 0);

针对不同屏幕分辨率不同，需要获取系统的屏幕分辨率

#include <windows.h>

int screen_width = GetSystemMetrics(SM_CXSCREEN);
int screen_height = GetSystemMetrics(SM_CYSCREEN);
char video_size[32];
snprintf(video_size, sizeof(video_size), "%dx%d", screen_width, screen_height);

av_dict_set(&dict, "video_size", video_size, 0);

设置屏幕录制画面起点，默认为原点（左上角开始x=0,y=0）

av_dict_set(&dict, "offset_x", "0", 0); 
av_dict_set(&dict, "offset_y", "0", 0);