Edit: BTW on your picture it's not (50,145) but (50,415) for the bottom left corner.
Edit: if quvi supports still works, you can ffplay "https://www.youtube.com/watch?v=rMXD5DxbXog" -vf perspective=60:90:589:147:50:415:582:418
(otherwise something similar should be doable with youtube-dl)
Edit: you can also do better and enable the perspective only in the part where it matters. Typically with something like -vf "perspective=60:90:589:147:50:415:582:418:enable='not(between(t,0,5))'"
Completely unrelated, but what do you think about vips (http://www.vips.ecs.soton.ac.uk/)? I recently discovered the difference in performance between im and gm and that let me to investigate vips, which is presumably (a lot) faster than both.
In principle, it looks promising (in particular, using ORC to compile image manipulation kernels to SIMD), but it is a different thing to im or gm. It's a library and a GUI. The library is slightly too low-level for most things I'd use gm for, but a GUI is too laborious.
Perhaps it could be integrated into GM or something similar, and used as a back end for certain operations.
ffmpeg -i zelda_720p.mp4 -vf perspective=60:90:589:147:50:415:582:418 output.mp4
Edit: BTW on your picture it's not (50,145) but (50,415) for the bottom left corner.
Edit: if quvi supports still works, you can ffplay "https://www.youtube.com/watch?v=rMXD5DxbXog" -vf perspective=60:90:589:147:50:415:582:418 (otherwise something similar should be doable with youtube-dl)
Edit: you can also do better and enable the perspective only in the part where it matters. Typically with something like -vf "perspective=60:90:589:147:50:415:582:418:enable='not(between(t,0,5))'"