Linux is case-sensitive, so "desktop" and "Desktop" are two separate folders.
Try
ffmpeg -i /home/sasha/Desktop/grand.m2ts
You could also use "~" alias. i.e
ffmpeg -i ~/Desktop/grand.m2ts
Both example point to the same place. The first example is the full path, and the second example is a relative path.
More information about formatting options
Linux is case-sensitive, so "desktop" and "Desktop" are two separate folders.
Try
ffmpeg -i /home/sasha/Desktop/grand.m2tsYou could also use "~" alias. i.e
ffmpeg -i ~/Desktop/grand.m2tsBoth example point to the same place. The first example is the full path, and the second example is a relative path.