It's always better to see for yourself than to trust what anybody says. It is not hard to download a video, bust it into frames, and enlarge them. The programs are free even. Virtualdub, from http://virtualdub.org is indespensible for looking at video critically. The program is both easy to use and well supported. To turn a video into a directory of stills, open the file and select "Save Image Sequence". Choose a directory and add enough leading zeroes so the files will stay in order.
Next, open Irfanview http://www.irfanview.com/
From the Edit menu, choose "Batch Conversion/Rename".
Browse to your directory, and select
"add all."
Go to Advanced Options, and select "Percentage of Original" and type
in 200%
Click "Use Resample Function for better quality" and click start.
It will take a while. Repeat, to make
them twice as large again, if you like.
The quality won't be quite as crisp as I can get with Genuine Fractals, which
costs $150, but it's plenty good for seeing-for-yourself purposes.
Many of my older video files won't
work for Linux or Macintosh.
The issue is "Divx Poisoning" a nasty that Microsoft pulled on the
folks who created Divx as a non-Microsoft equivalent.
.wmv files created from Divx masters play fine on Windows machines because they
were forced to do so, but that order did not apply to Macintosh or Linux versions
of Media Player.
Divx audio, even if the file has no
audio, but even if just the header is there, makes a broken file.
I use CinePak codec to make my master files now. It is ancient and extremely generic.