What are the ways to upload a pre-download video without using a kit or framework?

I"d like to ask all the great gods
if you don"t use packages or frames, what are the ways to upload pre-download videos?

for example,
used to be a "very tall" piece
all forced to 800x600 16:9 (proportional)

or a very high film
does not change its heel height, but it does not change the body of the film.

is there any way that the film will not be distorted (the film itself will not be changed, and the meat can not be seen), and the size of the film can be reduced?

Move_uploaded_file Picture uploadimage php7 php

Mar.04,2021

use canvas without any frame. The image selected at the front end is previewed by canvas, then compressed, and then uploaded to the backend

. The picture is drawn on the canvas of 800cm 600 and then uploaded by toDataURL or toBlob

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