The project needs a screen recording function. I saw a way to use Qt timer + screenshot + avilib to generate AVI + ffmpeg to combine video and audio:
Qt C++ screen recording function realization (avilib+ffmpeg) and dynamic library generation
https://blog.csdn.net/qq_35769071/article/details/125323624
After using it, there are many problems; first, the pos in the 32-bit avilib is a signed long type, if the size of the image to be saved is larger than the effective range of the long type, it will crash; if the resolution is 1920*1080, the video It can only be saved for about 2 minutes; secondly, the video and audio are recorded separately and need to be merged with ffmpeg.exe. If the continuous recording is 2 hours, the large files of avi and mav are merged with ffmpeg, which may cause problems;
A colleague found an open source C# example, Captura-9.0.0-beta4, which can support recording in selected regions; the bottom layer is realized by the ffmpeg command called by process;
I still think that the ffmpeg library of C++ should be used to realize this function;
The classmate recommended the basic ffmpeg book and the Windows library available for compilation. If necessary, you can download it from the link below;
Link: https://pan.baidu.com/s/1xnHlS0KLUelzSqT5nUleLg
Extraction code: hl1q
Here is an address for ffmpeg to realize screen recording;
FFMPEG screen recording (1) ---- recording desktop
https://blog.csdn.net/peilinok/article/details/102981560
It contains the common usage of ffmpeg, and an open source code for screen recording:
https://gitcode.net/mirrors/peilinok/screen-recorder?utm_source=csdn_github_accelerator
ffmpeg used
Problems encountered:
Need to turn off the log printing of ffmpeg
av_log_set_level(AV_LOG_ERROR);If you need to record an extended screen, you need to use the record_desktop_duplication class in Recorder to obtain all adapter information according to get_adapters. The coordinates of the main screen start from (0,0), and the extended screen is calculated relative to the coordinates of the main screen ;
auto adapters = d3d_helper::get_adapters(&error, true);Modify in the function get_dst_adapter, the logic in for needs to record the information of each adapter in the adapters, and then decide to record the screen; there is another question, how to get the zoom ratio of the screen?
int record_desktop_duplication::get_dst_adapter(IDXGIAdapter ** adapter)If the main screen is zoomed, you need to calculate the position relative to 1920*1080. Take my screen as an example:
