When you send videos through USB to another device, does every single byte completely transfer to it? Say if you had a video on your PC and decide to send it on your smartphone and then from your smartphone you upload it to Youtube does the quality stay like it was?
When you transfer pc to pc (or other device ) via usb or cable, you get an exact copy. When you upload to YouTube, they do their own encoding and the quality usually suffers.
A tip: if concerned about it one could always use a compression program such as WinZip or 7Zip to compress the files first, do the transfer then decompress it on the new location. The compression program will alert to any problem with the process.
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