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Comment by grecy | Hacker News Reader

I'd be interested to learn about the software that created the ASCII version of the movie.

Is there a simple way to do this, or would they have made something custom?

The algorithm dosent need to be too complex. You basically look at each still frame as grayscale, generate a hashtable of brightness values mapping to monospaced characters, and convert each grayscale pixel to a character.

You can do better than that by taking advantage of character shapes, though. Minimal example:

()

and:

)(

have the same brightness values, but we see them pretty differently.

Ideally you would use edge detection, maybe some object detection, and then be willing to compromise a little on brightness in order to make important edges nice. I don't know if there's software out there that does this, though.

A better example would be ( vs ), checking neighboring pixels to weight that pixel correctly.

How complex is an edge detection algorithm?

Depends on how complex you want. Something like a Prewitt filter is super simple.

aalib + mplayer would be my guess.

I remember reading about it back in the day, it was aalib and mplayer, but the conversion was done frame by frame with a patched version of aaview. Here's the write-up of how it was done: https://web.archive.org/web/20150311033450/http://onyx.chatt...

I know the person who made this and will probably see him at Chattacon this weekend. He told me how he did it but I forget now. I'll try to remember to ask him. I think he used something like VLC to split the movie into frames, then used another package to generate the ASCII art.

I pointed out this article to him, and he decided to (finally) take some credit for it. http://nooga.com/172237

I sincerely hope it doesn't lead to any legal troubles.

ffmpeg can output ascii videos

Whilst this statement is true, the torrent predates the earliest versions of ffmpeg, so it wouldn't have been what was used (which was what the OP was asking).

Whilst this statement is true, the torrent predates the earliest versions of ffmpeg

How so? The torrent is 12 years old, while ffmpeg was first released 15 years ago.

I remember using this program in 2001:

http://linux.die.net/man/1/ttv

aalib + video4linux = TV tuner outputting as ASCII.

[Shockingly I actually used this for a useful purpose - I had a messed up graphics card that couldn't run X stably due to machine lockups, but Linux console worked fine - so I used this to watch TV. I was a teenager at the time so it was a while before I replaced it.]

I don't know if you still can but you used to be able to do this to your whole screen on Windows using the NVidia control panel. Playing first-person shooters as ascii art looks pretty cool!

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