how people upload quality movies that are not out yet?

I’m just curious about this. Because some movies (at least based on the caps posted in threads) look great, like it’s Blu ray quality or DVD, but the movie just came out like a week ago in theaters so how is that possible? If people rip the DVD when it comes out, I understand. But when DVD has not come out yet, this makes no sense that they can get such good quality.
Answer #1
Many times a movie comes out in 1 part of the world and then weeks or months later it get released to other countries. Other times movies are pre-released before general release to selected people as DVD screeners which then make their way into DVD rips and uploaded to the internet.
Answer #2
Also sometimes movies are released early to the pay to view web sites.
These are recorded and made into WEBRips or WEB D/L
Answer #3
And they are often Asian released, Korean, for e.g., early and they rip that DVD.
Sometimes they crop the hard coded subtitles off – you can see that in an odd resolution, 1280 x 488 or some-such.
Answer #4
oh thanks, it all makes sense.