VideoCapture records with incorrect speed and FPS (Bug #3815)
| Status: | Cancelled | Start date: | 2014-07-16 |
|---|---|---|---|
| Priority: | High | Due date: | |
| Assignee: |  Alexander Smorkalov |
% Done: | 0% |
| Category: | highgui-camera | ||
| Target version: | 2.4.10 | ||
| Affected version: | 2.4.9 (latest release) | Operating System: | Any |
| Difficulty: | Medium | HW Platform: | x86 |
| Pull request: |
Description
Hi,
This is quite a fundamental issue and I was wondering if I'm the only one facing it but then I searched and there are others who have exactly same issue:
When you open VideoWriter with whatever FPS (say 25.0), you expect it to handle the frame write delay itself and if I did 10seconds of recording, it should playback 10 seconds of video, for example.
But what it does is that instead of dynamically catering and making sure the frames are written with the right time interval, the 10 seconds of recording I did gets sped up and shrinked to 2-3 seconds (fast motion).
This is quite a fundamental flaw and I would really appreciate pointers to the solution.
Associated revisions
Merge pull request #3815 from StevenPuttemans:add_camera_IP_regulations
History
Updated by Dmitry Retinskiy over 10 years ago
Alexander, could you check this?
Thanks.
- Status changed from New to Open
- Assignee changed from Vadim Pisarevsky to Alexander Smorkalov
Updated by Alexander Smorkalov over 10 years ago
cv::VideoWriter writes video frame by frame and use fps value for video file header only. It does not matter what is per-frame delay in your program, video will be always played with constant frame rate. it is expected behavior and if you want to presume actual program frame rate you have to insert duplicated frames manually in your code.
- Status changed from Open to Cancelled