My video will be in the 16:9 aspect ratio. There are a lot of ways to solve this problem. Irfanview is one of them. For quick tweeks and alterations it is the go to program.
It is freeware for non-commercial use, multilingual and dang near can open just about any image file format ever created. It is very simple to use.
Step 1 From the Image menu select Resize/Resample and you get a new dialog window.
Step 2 You will want to match the image with the recording dimensions of your video. For example, if you are recording in 1280 x720 that is what you want to type in the new size dialog box.
Before you can do that you will need to move 4 lines down and UN-CHECK Preserve aspect ratio (proportional). Otherwise, the software will only allow you to change just the width or the height.
Step 3 Now go back and change the new size to a width of 1280 and Height of 720 or what ever you happen to need for your video. Click OK, save the image and this is what you will have.
I now have a rectangle chalkboard that is in the 16:9 aspect ratio. This was originally a .png image but jpeg image will work the same.
This works best for non-photo images like backgrounds, wallpapers or solids. There is a distortion but it isn't that obvious.
Overlay a text title or what ever you want and, voila, you can have a different kind of title screen. It takes all of maybe five minutes. Now I gotta finish the story to go with that chalkboard.