This is a small Go program that takes a 4:3 aspect ratio video file, and transforms it to a 16:9 video using the GoPro SuperView method. This means that the image is not naively scaled, but a dynamic scaling is applied where the outer areas are stretched more while the center parts stay close to the original aspect rate.
This is not a 1-1 copy of the GoPro algorithm, but an attempt to reach similar quality of output using the open-source FFmpeg encoder.
Credits for the idea go to Banelle, who wrote the initial (Python) implementation.
Here is a quick animation showing the scaling, note how the text in the center stays the same:
This program requires FFmpeg in your PATH, please install it using one of these ways:
- Linux: install from your local package manager, for example:
apt instal ffmpeg - Windows: Download from https://ffmpeg.zeranoe.com/builds/
- macOS: Download from https://ffmpeg.zeranoe.com/builds/ or install using Homebrew:
brew install ffmpeg
Download a recent release from the releases page on GitHub. Or build from source using go build.
To run the program, launch the superview program with the -i (input file) parameter. Optionally, you can provide a -o (output) and -b (bitrate) parameter. Full usage instructions:
Usage:
superview [OPTIONS]
Application Options:
-i, --input=FILE The input video filename
-o, --output=FILE The output video filename (default: output.mp4)
-b, --bitrate=BITRATE The bitrate in bytes/second to encode in. If not specified, take the same bitrate as the input file
Help Options:
-h, --help Show this help message