This problem occurs because the Framerate of the original clip that you are trying to import is different than the one configured in the "video" tab in the Config Editor. With that said, Coach Paint adapts the frame of the imported clip to a format configurated on the Config Editor.
What does "Framerate" mean?
To understand what a video frame rate is, you first need to know that a video isn't just one continuous recording. Instead, it is individual images stitched together and flashed together on a screen in quick succession to make a moving image. The technical term for a video frame rate is frames per second (fps). So, a video frame rate basically refers to the number of times images are flashed on a screen during a given second.
So basically, if a video has 50 frames per second, this means that 50 images will be reproduced per second to give this illusion of movement. The more fps a video has, the more fluent the clip will be.
Importing videos with the “Match Video Format” disabled might be the cause of why exported videos are reproducing faster or slower, as you are letting Coach Paint import any framerate videos at the same time.
How can I see the fps of my clip?
If you have Windows:
In File Explorer, navigate to where the video you want to check the resolution and frame rate for is. Right-click the video file, and select Properties from the context menu.
In the properties window, go to the Details tab. Scroll down and you ought to see a Video section that will tell you everything you need to know.From the screenshot below, you can see that the video resolution is 1920 x 1080, and the frame rate is 25fps:
If you have a Mac:
The way to see the frame rate is by using the inspector. To open it up, launch Quicktime by double-clicking on your video on Finder, and once it's open click Cmd + I and the inspector will show up:
You can see that the frame rate is 24 in this example.
Let's see some typical cases
The fps of the clip and the fps configured in the Config Editor match:
Please note that the fps in the Config Editor is 50Hz
In this case, the original video has 50 fps and you have configured the Config Editor frequency as 50 fps, so it will work as expected.
The fps of the clip are lower than the fps configured in the Config Editor:
Please note that the fps in the Config Editor is 50Hz
Coach Paint increases the fps of the clip from 30fps (original) to 50 fps (output), as a result, the clip will run faster as now it has more frames per second.
The fps of the clip is bigger than the fps configured in the Config Editor:
Please note that the fps in the Config Editor is 50Hz
Coach Paint decreases the fps of the clip from 60 fps (original) to 50 fps (output), as a result, the clip will run slower because now it has fewer frames per second.
How to solve this issue?
To solve this issue, follow these steps:
Understand which is the video frame rate of your clip by following the steps mentioned above
Once you know what's the frequency of your video, open the Config Editor and change the format to the same value (or the closest existing one).
Close and Re-Launch Coach Paint
Note 1: By changing the video format in the config editor, you will probably lose all your work, so be sure to export any "In Progress" work before changing this config.
Note 2: all these cases were analyzed by having the “Match Video Format” disabled. If you have that option enabled, you just won’t be able to import any clip that does not match exactly the format and frame selected in the Config Editor.