Weirdly enough, my phone (Ocean) happens to be number 3 on the list, didn't expect that. But all the users are from Brazil for some reason? Is the phone really that popular?
The rule for preserving floppies is to not use Windows. Windows is known for automatically writing to disks, so you're not preserving the original anymore, you're preserving the changes that Windows made to the disk.
When you have a headline that does not say what the actual topic is, and you are forced to click the article to find out the topic, that is called "clickbait".
The missing dot is not just a thing that helps stabilize the colors in a picture, it's literally a missing dot. The first scanline is literally twitching left and right by one pixel every other frame. You probably can't see it on your TV without messing with the vertical hold.
Anyway, to get access to RAM before it is clobbered by other software, you need to run your code really really early. By the time the BIOS has decided to let you run code from a USB stick, it could be way too late.
RAID cards have option ROM that can run before a bootloader has started, that is one way to get something running earlier.
That has more to do with RGB -> YCbCr conversion, and how much blue contributes to Y (brightness). If you quantize YCbCr down to 8-bit range (0-255 range), you'll get RGB colors that can't survive a round trip back between RGB and YCbCr, but I don't think blue is particularly worse there.
JPEG is a different thing, first it does RGB -> YCbCr conversion, then it splits the image into blocks. Wikipedia article shows a good diagram of the 64 possible DCT blocks. Each image block becomes a linear combination of the DCT blocks. You did that for the Luma channel, then you do the same thing for the Chroma channels. It's even common to reduce the resolution of the chroma channels (chroma subsampling).
Then JPEG means that you are deleting information that is less popular after you've made your blocks. Often throwing out more information in the chroma channels than the luma channel. You're left with ringing (high frequency noise to fill the block), and blocking (differences between edges of adjacent blocks). Better compression codecs have ways of mitigating blocking and ringing.