Recording the true time with variable fps
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Recording the true time with variable fps
Hello, I am new to this software and I am wondering if I could use SharpCap for my purposes. I need to record videos with precise timings for synchronization reasons. For example, if I record a light that flashes every 10 seconds in real life, I need the light to flash at precisely 10 seconds when I play back the video. However, my webcam sometimes experiences variable framerates that drops slightly below 30fps, for example it sometimes dips to 25-29fps. However, the video saves as though the frame rate is 30fps, and as a result the video is slightly faster than real life. How can I save a video that records real time instead of it being artificially sped up?
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Re: Recording the true time with variable fps
Hi,
I think the best option here is to record in SER file format rather than AVI file format. SER stores a timestamp for each frame in the file, so you can get the information that you need. A useful program called 'SERPlayer' will let you play the files, including seeing the timestamp for each frame. The file format is relatively simple, so if you process the images yourself then you can probably adjust to reading SER files (see http://www.grischa-hahn.homepage.t-online.de/astro/ser/)
Unfortunately, SharpCap doesn't have the capability to do this sort of timestamping of frames with AVI files - I'm not even sure if it is easily possible, as the setup for writing AVI files is very much based around setting a frame rate when creating the file.
Hope this helps,
Robin
I think the best option here is to record in SER file format rather than AVI file format. SER stores a timestamp for each frame in the file, so you can get the information that you need. A useful program called 'SERPlayer' will let you play the files, including seeing the timestamp for each frame. The file format is relatively simple, so if you process the images yourself then you can probably adjust to reading SER files (see http://www.grischa-hahn.homepage.t-online.de/astro/ser/)
Unfortunately, SharpCap doesn't have the capability to do this sort of timestamping of frames with AVI files - I'm not even sure if it is easily possible, as the setup for writing AVI files is very much based around setting a frame rate when creating the file.
Hope this helps,
Robin