Videos not working in Irfanview
I love Irfanview. It's great, I use it as my picture browser and quick-edits tool. I use it to browse through folders which might contain MP4 or Webm videos, as a substitute for gifs.
However, for the longest time, and on repeat occasions, the videos don't render -- I can hear it (if it has audio), but I can't see anything.
A long time ago, I googled for a solution, and basically found none -- but I figured out that if I open a video in Irfanview, and then open a *second* video in a separate Irfanview instance, the second one works perfectly. And I've been suffering along with this method for ages.
I finally figured out the root cause: Codecs.
Aside from Irfanview, I also use the K-Lite media codec pack, because not being able to open an MP4 encoded in some arcane encoding format is horseshit. And at some point in the past, I must have picked it to use hardware encoding of some variety, instead of software. (Or it defaults to it.)
THIS IS THE PROBLEM
To fix, just update / reinstall the codec pack, but don't pick "quick update" -- go through the settings. Choose software decoding.
I'm sure hardware encoding has it's place somewhere, and one day, I might try and open a video and just get fucked because I chose to have my CPU brute-force the encoding instead of using my high-end graphics card.
But today, I browse ancient memes on my HDD.