OK. You've taken a 360 video and when you watch it you notice one thing. The default view a person sees is the opposite to what you want. You faced the 360 camera in the wrong direction. Now you'd think this is an easy problem to solve. It really isn't.
For example I took a video on a metro train. The 360 camera faced the end of the train and really, there was nothing to see. Yet the other view, the view I wanted to share, would enable people to immediately see the inside of the train carriage plus more importantly, out the windows on each side. Once people know what they can see, they're more than likely to start exploring. But when you just see the end of the carriage, well people are just going to leave and watch something far more interesting.
You would think being a 360 video you could just select the view you want as the default. Nope. Not so easy. In fact you have to have a program where you can rotate the view and create the video using the new view. Amazing isn't it. Something that should be as easy as entering a parameter, or two, to set the default view isn't possible.
Yes you can use Adobe products to create a video with the default view being what you want, but let's face it, Adobe products aren't cheap. If you scan the internet for suitable software there's actually none for free that easily do what you want. I did find one person who thankfully shared they'd worked out how to use ffmpeg to reverse the default view, but personally I feel command line tools are a last resort. Give me a nice graphical user interface. The person share their approach on Reddit.
Now you might ask (or perhaps not) how did I work out how to reverse the default view on a 360 video. When I look at the raw video from a 360 camera before the images are stitched, there's two ball like images. One image for each lens. The default view is on the right and the reverse view is on the left.
I kept thinking surely I could just use a video editor and switch the left half with the right half and then start the process of creating and editing the video. It turned out I couldn't find an easy way to do this and then perform the next step which is called stitching. Stitching takes these two balls, joins the images and creates what is called an equirectangular image. The following is the stitched image.
Keep in mind this is just one moment in the video which is a continuous series of this type of image.
So I decided to see if I could work with the stitched image. In effect what I wanted to do was to take the right half of the image and move it to the left and then take the left half of the image and move it to the right. That way the default view in the centre becomes the outside edges and the outside edges now in the middle and become the default view.
So now I had a working theory, I needed some software I could use to see if my theory worked. I ended up using the software called Davinci Resolve. The software can be downloaded for free but I did have to accept the limitation of the free version. My video was shot at 4096x2048, but Davinci Resolve (in the free version) could only do up to 3840x1920. A small drop in quality for the result I wanted, at the price I wanted (free), was OK by me.
I then used Davinci Resolve to edit the video file and created the video with the default 360 view I wanted. The following video shows the steps I took to create the video.
The following is the video or me travelling inside the Frankston to Melbourne train that I created using Davinci Resolve to give the default view that I wanted.
Hopefully this information might help solve your problem if you are faced with the same problem I was.
Kelvin Eldridge
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