Integrity of sent pictures and videos in VK?

Question

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And high quality 2k or 4k jpg png bmp mp4 files will not be altered when sent to VK in messages? Convertible? Is the quality going down? Or bit for bit is the same thing that you downloaded and downloaded?
I have a suspicion. what if we compare the files of pictures and movies bit by bit. sent in messages. then they will be different!

Answer 1

If the picture is sent, then they are pressed, if the file is bit by bit