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August 13

May there be any connection between, absence of base system device driver on my laptop, and its overheating followed by shutting down sometimes?

HOTmag (talk) 09:43, 13 August 2024 (UTC)

Yes. I'm simplifying but in the old days thermal protection was controlled directly from the BIOS. Nowadays it's done by ACPI. If the OEM driver is missing the fans won't kick in when they should and the hardware may shut itself down (in an uncontrolled manner) to protect itself. For details see: https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/11_Thermal_Management/thermal-control.html#:~:text=6.-,Critical%20Shutdown,a%20predetermined%20time%20has%20passed. 41.23.55.195 (talk) 14:15, 13 August 2024 (UTC)

August 15

Fast Fourier transform

In the website there's an example FFT algorithm structure which uses a decomposition into half-size FFTs. Does the 🔝 half-size FFT which consists of x[0], x[2], x[4], x[6] pertain to switching circuit theory which "is the mathematical study of the properties of networks of idealized switches?" Below the example FFT algorithm structure is "a discrete Fourier analysis of a sum of cosine waves at 10, 20, 30, 40 and 50 Hz." Afrazer123 (talk) 22:05, 15 August 2024 (UTC)

For context, this presumably refers to the first picture in the article Fast Fourier transform. And here's Switching circuit theory.  Card Zero  (talk) 03:34, 16 August 2024 (UTC)

No, there is no relation between this FFT structure, which is about linear operators on real and complex numbers, and switching circuit theory, which is about digital logic operations (except that both can be characterized and diagrammed as graphs). In the FFT diagram, E(0), E(1), E(2), and E(3) are complex numbers that represent the DFT of the Even-numbered input numbers; similarly O(0)... for the DFT of the odd-numbered inputs. The Ws are complex "weights", numbers that are multiplied by the Os; those products are added to the unmultiplied Es that they are paired with, to make the output complex numbers that represent the DFT of the full input sequence of numbers. Dicklyon (talk) 15:49, 16 August 2024 (UTC)

August 18

Small Blue-Ray player

Where can I get a Blue-Ray player which (1) plugs into an HDMI port on a desktop PC, (2) is small enough to be placed on top of said desktop PC's tower unit without any problems, and (3) does not require deliberately circumventing DRM in order to watch Blue-Ray disks? I've just now bought a compact Blue-Ray player which plugs into a USB port, but discovered that it won't work unless I install AnyDVD (which I don't want to do, for obvious reasons!) Just to be clear, the issue is not cost, but size -- my computer is so old that it can only read DVDs and not Blue-Rays, so I need an external Blue-Ray player, but at the same time the space for its installation is severely limited, so I need one small enough to place on top of my PC or else I don't have any room left for it. As possible alternatives, would it be possible to (B) use a USB to HDMI adapter (is that even an actual thing?), or (C) when it comes time for my computer's next overhaul (which I wanted to do this winter, but didn't), replace its internal optical drive with one which can read Blue-Rays while remaining backwards compatible with DVD's and CDs? 2601:646:8082:BA0:F993:EB64:4176:5F31 (talk) 03:12, 18 August 2024 (UTC)

So how big is the top of your PC? For instance, this Blu-ray player from Sony is 320 x 45 x 212 (mm). I think that will fit fairly neatly on top of a typical full or mid size tower case, overhanging by only half a centimeter left and right. You might clarify point (3). Why would your newly bought hardware refuse to work at all without third-party software to defeat digital restrictions? Is this to do with region locking, in fact? Is that Sony player likely to have the same problem? (I'm not fussy about resolution, so I've only ever owned regular DVDs, excuse me if I'm ignorant of any well-known facts.) I also wonder what software you're playing the media with, and whether, say, VLC media player or mpv (media player) is the actual solution here. Actually I just read in the mpv faq "It is a fact that playing DVDs/BDs gives a much better user experience when ripped to files", so perhaps the page Blu-ray ripper is helpful.  Card Zero  (talk) 07:00, 18 August 2024 (UTC)

Region locking is most emphatically not an issue here, because the player was set for region 1 and all my Blue-Ray disks are also region 1 (except for one or two which are all-region), and I tested it with a region-1 disk -- plus, after it refused to play, I used the Cyber-Link advisor tool for diagnostics, and it said specifically that the problem was HDCP, or more specifically it said that a USB port won't do for a Blue-Ray player and I have to use an HDMI port or similar! (And yes, I didn't know about this either until it came up just the other day -- in fact, I had to look up what HDCP is and what it requires for compliance!) So, if the Sony player plugs into the HDMI port (my computer has a spare one), then there should be no problems of that sort! As for dimensions, they should be acceptable -- it would hang off by 3-4 inches on either side, but that's not a big deal! Thanks for the info! 2601:646:8082:BA0:F993:EB64:4176:5F31 (talk) 11:02, 18 August 2024 (UTC)

Oh, I mixed up width with depth, my apologies. It would fit even better if turned sideways ...

The HDCP article has this quote: "the main practical effect of HDCP has been to create one more way in which your electronics could fail to work properly with your TV." I wonder whether you might have better results connecting the player directly to the monitor, I don't see that involving the PC will bring much joy to the experience in this restrictive climate.  Card Zero  (talk) 11:15, 18 August 2024 (UTC)

Did you actually buy a USB (standalone) Bluray player? I'm not convinced such things exist, since I'm not sure what the USB would be for. Some Bluray players may accept USB sticks but I don't see the purpose of connecting to a computer via USB. Cyberlink definitely would not be involved. It seems much more likely that you bought a USB Bluray reader or reader+writer i.e. an external optical drive with a USB interface. This is what you need to play Blurays on your computer and USB should not be a problem. The connection interface of the reader is largely irrelevant since the content is being decrypted on the computer not on the Bluray reader. However any commercial authorised software will require HDCP. This means your monitor needs to be connected to your computer with HDCP enabled (and sufficient version). HDMI is the best solution here since it's sort of designed for that sort of thing, so connecting your monitor to your computer via HDMI is the best solution. Failing that DisplayPort and DVI might work. You should check settings on both your monitor and GPU and ensure HDCP is enabled and if you can choose version, chose the highest version that works. Again, 4k is far more likely to be a problem. If for some reason your connecting your monitor to your computer via VGA, there's no way to have HDCP so it won't work. If it's an AIO or laptop, it might still need HDCP to be enabled internally to work. If you're using USB to connect your monitor to your computer, it will depend on how it's connected and possibly other stuff. I'm fairly sure it can work but it can be complicated. [1] IMO if at all possible try to just connect your monitor to your computer directly with HDMI. I suspect, but don't know, that this is what the Cyberlink advisor was suggesting. Connect your computer to your monitor via HDMI not via USB or DisplayPort. Of course if your monitor doesn't support HDCP, or doesn't support sufficient version, then unfortunately you're probably SoL if you want to use a simple authorised solution. Again unfortunately your only real option there is to get a monitor which supports HDCP of sufficient version. As said, 4k will be far more of a problem than traditional Blurays. But it's also possible that Cyberlink has been forced to require HDCP higher than a standalone Bluray player needs so it's possible you could use a standalone Bluray player even if you can't get playback working on your computer. Nil Einne (talk) 15:31, 19 August 2024 (UTC)

BTW, be aware that even if you get it working, it might not work for newer titles without updates, and note this applies whether you use a computer solution or standalone player. See e.g. [2] Nil Einne (talk) 15:38, 19 August 2024 (UTC)

I should also clarify that besides HDCP, I think there also needs to be internal protections on the computer probably TPM of some variety since they're also supposed to stop the decrypted stream from being intercepted on the computer rather than just after it is outputed. Nil Einne (talk) 15:49, 19 August 2024 (UTC)

Unless your computer happens to have a HDMI capture card or capture device, I fairly doubt a Bluray player exists that can connect to your computers HDMI port. The HDMI port on your GPU (including any iGPU) is almost definitely only capable of acting as an output device, it cannot accept any input. (I mean most GPUs can't even do HDMI-CEC.) Even if you did happen to have a HDMI capture device like an Elgato or whatever, fair chance it still won't simply work. The Bluray player will almost definitely need HDCP enabled when it's playing a Bluray (perhaps you can disable it or it's not enabled for DVDs, not sure), and the capture device is unlikely to support HDCP. You could potentially add a HDCP stripper or HDMI splitter but that's adding a lot of work and you might need more than that. This seems way too complicated for what you want to do. Instead of trying to send the Bluray output to your computer, you should concentrate on sending it to your monitor. If your monitor has a HDMI port and it supports whatever version HDCP your Bluray player requires which I think for traditional Bluray's this isn't very high so it probably does, then you can likely just plug the Bluray player into your monitor and it will work. If you're already using the sole HDMI port on the monitor for your computer, the easiest solution would be just to unplug the HDMI from your computer and plug it into the Bluray player when you want to watch something. Alternatively you can get cheap and small HDMI switches from AliExpress and the like. Some fancy Bluray players may let you plug in a HDMI from a source device and act as a switch itself, like an audio system etc, but these are likely to be expensive and I expect on the bulky side. (Not because they really need the space.) If you don't have a HDMI input on your monitor, you could try looking for one with DisplayPort output assuming this is what your monitor is using but frankly I'm not sure they exist. You could try using some sort of active HDMI to DisplayPort converter, but especially with HDCP, I'm not sure how well this will work. Frankly, you might be better of just getting a monitor with HDMI input. If you don't have a standalone monitor but instead an AIO or laptop frankly you're IMO better of just getting a small HDMI capable monitor. The alternative is to get playback on the computer working. Trying to capture the HDMI output from Bluray computer is to be blunt a very daft solution however you spin it. Nil Einne (talk) 15:06, 19 August 2024 (UTC)

August 22

stop cursor blink on all apps in windows 11, especially Geany

Hi, I want to know how to stop the cursor blinking across all of Windows 11. I have disabled blink in Settings, but some apps still blink, and I can't fix it. The worst case is Geany, my otherwise excellent text editor. Any suggestions? IBE (talk) 00:12, 22 August 2024 (UTC)

Oh hey that's based on Scintilla, I use SciTE myself.

Geany sets its own blink rate. There is some confusing discussion about how Scintilla GTK (which is what Geany is?) respects a setting for GTK blink rate "if available". On Windows, I guess it isn't.

There's a cursor width setting in the Geany manual, which in theory will turn the cursor off entirely if set to 0. You might be satisfied with that, if it works.  Card Zero  (talk) 14:31, 22 August 2024 (UTC)

This is hard, from a programmer's point of view.

The blink setting in Windows affects the text inputs rendered by Windows' toolkit. All applications that have outsourced their text inputs to Windows' toolkit automatically follow this setting. But Windows' toolkit is only available on Windows, so if you want to create a cross-platform application (like Geany), you can (A) maintain two versions, one with Windows' toolkit, one without; (B) use a cross-platform toolkit; (C) build your own text inputs. (A) is a lot of work, as you have to maintain two versions of every graphical input/output function. Geany uses (B), in the form of the GTK toolkit. I suppose GTK's developers may try to read Windows' settings, but the interface to Windows' settings is a poorly documented moving target.

There may be a tool on Windows to configure GTK. I haven't used Windows in ages, so I never tried this myself. That may help for the GTK-based applications, but not everything else. Some applications could have hard-coded blinking, so no way to change it. PiusImpavidus (talk) 08:25, 23 August 2024 (UTC)

Well, in this case, poorly documented moving target is undue. It's GetCaretBlinkTime(), and that was true in 1996, which is the age of my copy of WIN32.HLP, and it's still true today. I just tried, it returned 530 milliseconds. Microsoft's online (web) help closely follows WIN32.HLP, if you can find your way into the right parts of it. (Reading an actual .hlp file in 2024 is not so simple, I must admit, since they removed the reader years ago.) I'd imagine that every Windows GTK-based application ships with its own copy of GTK, rather than attempting to use or install system-wide shared libraries. For instance I see my GIMP has a libgtk-win32-2.0-0.dll, hidden among a million other dlls, in its \bin alongside the application binary. So a system configuration for GTK on Windows is probably not an option.  Card Zero  (talk) 11:03, 23 August 2024 (UTC)

Thanks for those replies. Looks like I'll have to keep searching to see if there's a way around it. Sad because when I had it on Windows 10, it was all good for some reason, easy to disable the blink (I'm pretty sure there was a setting under Edit->Preferences). IBE (talk) 00:08, 24 August 2024 (UTC)

August 23

Lower half of Dos Code pages

Code page 850 cites both IBM and the International Components for Unicode in the header of the table describing the layout of the code page. IBM and the article provide a table where the characters at positions 0x00–0x7F match Code page 437, but International Components for Unicode provides a mapping that instead agrees with ASCII including ASCII control codes. The IBM mapping agrees with the IBM table not the Unicode mapping. Is the situation here something like the whole ISO 8859-1 vs Windows-1252 thing, or is one of the sources just wrong?

Other Wikipedia articles on Dos codepages have similar issues, but some only provide a table for the upper half and state that the lower half is the same as Code page 437. What should the articles say? McYeee (talk) 20:08, 23 August 2024 (UTC)

References

August 24

What means java

What java means 2409:4042:EBB:FC77:69FA:EA09:283C:C31A (talk) 15:18, 24 August 2024 (UTC)

Your question is unclear. What it means will depend on the context. Is it the country or some other place? Perhaps the programming language. Or one of the many things listed at Java_(disambiguation)? RudolfRed (talk) 18:57, 24 August 2024 (UTC)