This method was tested on Pixel, Huawei, Xiaomi, Samsung and Nokia phones and more than 150 videos. Here’s some results from pixel 2 XL (medium quality);
 🔹    94.3MB compressed to 9.2MB in 11 seconds
 🔹    151.2MB compressed to 14.7MB in 18 seconds
 🔹    65.7MB compressed to 6.4MB in 8 seconds