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Comment Re:mpv does support user supplied shaders (Score 1) 218

mpv allows the user to supply GLSL scripts using the --opengl-shaders=filename option, and it can save single screenshots to files after those shaders have been applied (Ctrl-S), and mpv is scriptable (in Lua or C), so all you need to do is write a script that single-steps through the video, then writes such a post-processed screenshot to a pipe which you can use as input to "ffmpeg".

Doesn't mpv support direct output to a series of PNGs? MPlayer does it simply with -vo png.

Incidendally, I'm working on something related to the original question. I use shaders for math art demos, and I already have the option of using image files as the input (shameless example). It would be trivial to accept a new file for each frame, so it could process video from a series of images. The speed would only be a couple of FPS due to I/O bottleneck, but it won't be realtime anyway. The reason I haven't done this so far is that my focus is on the math of iterated shaders, not processing some existing video. Still, it would be fun to do some day, and of course I'm looking at ways to do it in realtime (the GPU is fast enough, but I/O is harder).

Lastly, you could use a screen recording software instead of the clunky series-of-screenshots idea. I did this for putting my first few demos on Youtube, but the quality is awful, so I much prefer taking the PNGs and encoding separately.

Comment Re:They need better cyber (Score 1) 276

Yeah, I tried putting a giant rubber sheath over my monitor too, but apparently that doesn't stop you from getting an infection when you cyber. I feel his pain.

I thought sexual education in the US was all about abstinence, never mind the resulting teen pregnancy rates. That rubber thingie sounds like some European socialist hippie plot.

Comment Re:My art is shit (Score 1) 562

To me, music means sound waves in the air, something meant to be listened with your ears. Whenever I see these hipsters talking about vinyl or cassettes etc., I wonder if they care more about the storage format than the music itself. If they cared about the music, they might choose a format that doesn't degrade the music so much.

Comment Re:When are we going optical? (Score 1) 192

Current systems can generally output S/PDIF digital audio through the line-out port; it's a standard feature, though somewhat hidden. You just need to connect an RCA adapter (use the right/red channel) and enable the S/PDIF output switch in the sound card settings. Audio quality is the same as Toslink (optical S/PDIF), though the signal may attenuate over very long coax links. There are devices like this one available which convert from coax to Toslink.

Ah, good point. I'm pretty sure I've encountered this once before, with a sound card that was specifically advertised to output S/PDIF, while having only 3.5 mm jacks. Alas, it's not quite general, as my Thinkpad is lacking the feature (the digital outputs are all labeled with "HDMI" in alsa).

Incidentally (and you probably know this already), the Toslink output in some earlier laptops was hidden within the line-out jack. A clever solution IMHO, as it doesn't mix up different kinds of signaling in the same electrical pin, and the light makes it clear there's something going on besides plain old analog. OTOH, it requires a small adapter for the Toslink fiber.

Comment Re:When are we going optical? (Score 1) 192

It's obvious if you look at the way people treat their cables. You can't expect them to obey something as esoteric as bend radius limits when their plain old copper wires hardly survive in one piece.

Incidentally, S/PDIF isn't doing too great these days, which is a shame. One of my old laptops from 2005 had optical audio output, and it was awesome especially given the poor quality of its analog output. Since then, this feature has been missing from most laptops, and even with desktop mobos you have to be careful. It seems since HDMI came out, you shouldn't need any other way of getting raw digital audio, which seems especially silly with something like 5.1 or better -- you'll probably want something more than the toy speakers in the TV or monitor.

Also, it sucks to have a professional laptop with DP output, only to realize that the projector at the venue only has consumer-style HDMI or even VGA.

Comment Re:Fun (Score 1) 449

Today we have a lot more learning resources out there, and the hardware is much more powerful but in my mind it just isn't as fun. There is certainly no way to whip up something that would "wow" anyone. It's more a tool now than a fun hobby.

You can always "wow" people when you do something remotely skilled and original (see my other post). People are used to throwing a ton of computing power at every single problem, but that doesn't make things inherently more interesting. I write software to make art, and I'm pretty sure I've seen the "wow" in action.

It's an interesting point, though, that computers now are more a tool rather than a novelty in themselves. With my algorithmic art, I like to remind people that it's simply math, it's just done on computers to make it fast enough. Nevertheless, the practical work is all about writing software, and it's certainly a fun hobby -- scratching my own artistic itches.

Comment Re:'Fun'? Not so much. (Score 1) 449

writing software yourself is almost pointless, you can download just about anything you want, too.

Not if you're doing anything remotely original. There was no software for doing my algorithmic art, and I guess if there had been, it wouldn't count as art. Similarly, I've done software for math and physics research. It's mostly math and algorithms, though, so technically the ideas could be implemented in something like Matlab (static images yes, live GPU-powered demos not so much). There's also the whole idea of knowing and controlling every aspect of your work that counts in art as well as science. (Unfortunately, there's quite a bit of proprietary "science" out there, for example in molecular modelling.)

As for electronics, FPGAs made it fun for me again, not the least because they bridge a conceptual gap between software and hardware. I don't even need to get into Linux and Free software in general :)

Comment Re:I tried to get the patch (Score 1) 256

Yeah. Seems to me an awful lot of affected people ought to bill Microsoft for having a tech guy come set things right for them.

I'd like to paraphrase that as "people ought to bill Gates" but I guess I'm too late.

Seriously, though, what is it with computers/software that makes them exempt from basic consumer protection laws? You pay Microsoft for a product and they sell you a broken one, is it too much to ask for them to come and fix at their expense?

Comment Also, arrow keys that don't move the page (Score 1) 309

The article mentions scrolling up/down small abounts with the keyboard, presumably by using arrow keys. They are also handy for browsing pages wider than the browser window. Alas, many sites break the sideways logic -- when pressing left or right, they send you to the prev/next section of the site. For example, next topic on a discussion forum.

I wonder who actually uses such a "feature" -- surely the kids today don't even use a keyboard, that relic from the 1960s terminal world.

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"Well, it don't make the sun shine, but at least it don't deepen the shit." -- Straiter Empy, in _Riddley_Walker_ by Russell Hoban