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June 5

File Formats

I just converted a “.flv” into “.mp4” using “YTD” in “ipad”, “iphone” and ”PSP Video H.264” conversion versions, the latter seem to give me the least (from a 33MB to 123MB).

Question is, is “.flv” the best of or is there something else? - Because, “.flv” doesn't work on the smart phone without a special software...

43.245.123.33 (talk) 17:58, 5 June 2017 (UTC)[reply]

.flv is a Flash video format. Given the recent loss of market share Flash is experiencing (thanks in no small part to HTML5), I would not recommend it for use in anything but a dedicated flash application (including web apps, naturally). Interesting it is, or was (I'm not sure if they changed) the format of YouTube videos. Mp4's compression are more common and the licensing on it is less restrictive (it's free for streaming which, in turn is free to the end user) than that used by .flv files. So I would suggest mp4's as the preferable format. That being said, I would also go one step further and recommend .mkv as a preferred file format: It uses an open source container format, and itself is maintained by a company that has a broad footprint and little signs of losing market share. It is technically better in that it produces fewer compression artifacts, and pragmatically better in that, being based on an open source container format, it is likely to outlive either of the other two. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 21:32, 5 June 2017 (UTC)[reply]

Don't understand what you mean by "technically better in that it produces fewer compression artifacts". Both MP4 and mkv are containers. (So for that matter is FLV, or F4V which are often given the extension FLV anyway.) You linked to the DivX Plus HD for .mkv, but a mkv can contain any number of different video compression formats. MP4, is more complicated, you may legitimately question whether private streams or non registered video codecs are a proper use of the container. Still even if you restrict usage to registered codecs, there is still a large variety.

More importantly perhaps, by and large both are most commonly used for h.264 (and actually most modern FLV too) . There may be some advantages to putting the video stream in mkv, but if it's the same video stream there are no fewer or more compression artifacts whether the stream is in mkv, MP4, FLV/F4V or raw unless there is some seriously wrong with your playback device. The same if the audio is AAC and again for mkv and MP4. (FLV is perhaps more complicated when it comes to audio as MP3 isn't uncommon. I think the same for F4V)

The source encoder does matter. Since you linked to DivX Plus HD, I'm not sure if you intended to suggest it as the encoder. But if you did, this is still poor advice from a quality standpoint. x264 is generally regarded as giving the best quality encodes for most resonable time frames. It's used by many including last I heard, Google for YouTube.

Encoding settings also matter, and I believe DivX Plus HD does set some more stringent requirements than some others, however what matters than is the encoding settings (bit rate etc). Saying something is in the MP4 container or FLV container doesn't tell you what encoding settings were used. It may be the settings were less than that allowed by DivX Plus HD, but that's a distinct point. And anyway, that only applies if you refer to DivX Plus HD rather than the mkv container.

Of course the other important reminder is unless you need to re-encode for some reason like playback issues, there is no quality advantage to transcoding to another format. I mean if you do extensive pre-processing, then maybe there is an advantage to that, and you'll need to consider what to save after that processing, but that's a different point. (Likewise if you do need to transcode for compatibility reasons.)

Nil Einne (talk) 14:23, 6 June 2017 (UTC)[reply]

Yes, but the container formats all have a dominant format for video and audio encoding. In this case, my comments were in reference to the most dominant encodings for those two containers. 9 times out of ten, when someone produces an .mkv file for example, it is a DivX Plus HD file, meaning it is MPEG-4 AVC encoded video with AAC encoded audio. I don't see the point in disambiguating here, as the vast majority of playback and editing software will support every common encoding of a container if they support that container, and the defaults will be for the formats I described. We are, after all, volunteering here to answer questions, not to create new questions. I think it is preferable to give the OP an answer to their question than to launch into an in-depth explanation of how multimedia data is digitally stored and compressed which the OP may not have the slightest interest in. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 13:06, 8 June 2017 (UTC)[reply]

Bullcrap. The vast majority of mkv are H.264 encoded with x264. Very few people who know what they are doing use DivX Plus HD. This is of course a good thing, since x264 is far superior for DivX Plus HD. Heck not all MKVs even meet the requirements for DivX Plus HD. (Not necessarily a good thing, but it depends on the target audience etc.) Most of the rest of MKVs are content which was encoded by some commercial source (streaming or download sources like Amazon, Netflix, iTunes, BluRay etc) with a probably unknown encoder, although as I said x264 is fairly commonly used commercially but I suspect Apple at least uses neither (I'm assuming they do transcode internally for iTunes files rather than keeping compliant files as it, but I don't really know); and then remuxed into an MKV. Probably the most common alternative codec for H.264 to these is Intel or Nvidia's hardware one, with AMD trailing badly but still coming before DivX Plus HD in usage share. To be fair, I'm fairly sure DivX Plus HD is better than these, but it doesn't change the fact it's not commonly used.

Further as I already said, it is also the case for MP4 and for FLV (particularly if it's really as it probably is F4V) that H.264 (coming from whatever encoder) predominates. The audio as I've already as it a bit more complicated. Thinking a bit more, my original answer wasn't totally correct, AAC isn't as common as you suggest or I also inadvertedly implied. Many MKVs have AC3 or sometimes DTS, again this is audio originating from the source. AAC would be better even for multi channel but audio systems don't necessarily support decoding AAC and people get silly about audio even going as far as to pointless use LPCM. Anyway the main point is it isn't uncommon these audio streams are preserved rather than transcoded and so the MKV doesn't have AAC. (From an audio quality standpoint it obviously doesn't matter, in fact sicne the audio hasn't be transcoded it is technically superior. Still it is mostly wasted bitrate and it's far more likely someone will notice the difference by using those bits for the video instead of the audio.)

Yet you specifically claimed that mkv had fewer compression artifacts which clearly makes no sense when all 3 generally have the same video codec and I think it's clear you're not thinking of audio compression. (Incidently I suspect MP4s have AAC more commonly than mkv although as I already acknowledged FLV is a little more complicated when it comes to audio some still do have MP3.)

Also this is irrelevant to the OP when they are transcoding or encoding the content themselves. Whatever others store inside their MP4s or MKV or whatever, it is not going to make their MKVs better quality if they store VP9. Nor are they going to have worse quality because they used x264 codec (instead of the crappy DivX Plus HD) but stored the output in MP4 instead of MKV. In fact if they did use DivX Plus HD as you linked to them, depending of course on quality settings especially bitrate, it's likely they would have ended up with worse quality despite sticking it in MKV than if they had used x264 no matter that they stick it in MP4 or FLV. (Not that I'm saying they should stick it in either, the point is there's a reason why it's important to distinguiush between container format and video codec.)

In other words, your advice wasn't just wrong, it was useless. There's a difference between simplifying things, and speaking bull crap, and you did the later as nearly all of what you said was misleading or just plain wrong. And yes, when someone answers a question but a big chunk of their answer is basically completely wrong, it's fair to point this out. It's good to volunteer to help but if you are wrong you should still expect to be called out on it.

Nil Einne (talk) 12:57, 9 June 2017 (UTC)[reply]

P.S. In case there's still some confusion, here's some far better advice than your largely wrong one. MKV is arguably the best container format to use but it's not going to give better video compression or fewer compression artiftifacts. That would common from choosing the best video codec. This would often be H.264 using the x264 implementation, generally not DivX Plus HD. HEVC may be the best bet in the future, the licencing controversy seems to have died down a bit, and x265 is starting to get to the stage where it's getting close to at least matching x264 at many bitrates. AAC would also often be the best audio codec, Opus is technically superior but not many use it and compatibility may be a bit hit and miss so I'm reluctant to recommend it. However for many uses, chosing MP4 or even FLV or more likely F4V as the container, isn't really going to be that much of a disadvantage. And for better or worse, since this whole problem arose because of compatibility with crappy players (as I said below), you're probably going to have less compatibility problems by storing the H.264 (preferably from X264) in MP4 than storing it in MKV. (For example, as far as I can tell, the default iOS video player doesn't support MKV. Unsuprisingly it does support MP4 including with H.264. Android nowadays does tend to at least partially support MKV given that WebM is a subset of MKV and Google's push to it. They also support MP4 at least when it has H.264 and AAC as with nearly everyone nowadays.) Although I really think the best solution is just to avoid crappy players. If the problem is solely related to container compatibility, you can of course simply remux into a different container rather than transcoding for now quality loss or size gain/loss although I'd repeat you're probably better of avoiding crappy players. Note if you do choose MKV, there's probably little point using the DivX Plus HD specific extensions, few others do so. Nil Einne (talk) 13:11, 9 June 2017 (UTC)[reply]

Wow. Butthurt much? I stand by everything I said and am not even going to bother reading the crap you wrote past the first sentence. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 13:46, 9 June 2017 (UTC)[reply]

You usually don't need special software to playback FLV on phones. Any half decent video player should be able to do it. If your video player can't it's probably junk, the software that can do it are just normal players not special. If the FLV actually contains h.264 as is often the case, than you should also get hardware decompression. Still if you really want to use a shitty player on your phone and it is FLV with h.264, it will be better to simply change container probably to MP4. There is no need to transcode. This will mean the quality will not change nor will the size (by much). Of course if you don't actually notice the difference between the FLV and whatever you transcode it to, then there's no real harm for yourself in doing so. Nil Einne (talk) 14:29, 6 June 2017 (UTC)[reply]

Correcting author name in a few hundred pages (references)

Hi, I am wondering if someone knows an easy and fast way (a bot?) to correct Paulin Martin's name in the bblg footnotes of literally hundreds of articles (https://en.wikipedia.org/wiki/Special:WhatLinksHere/Paulin_Martin) where it is erroneously spelled Jean-Pierre-Paul Martin? The most simple way would be to change it to the form it has on books i.e Jean P.P. Martin or even more simply J.P.P. Martin.^{[D 1]} Thanks. darthbunk pakt dunft 20:58, 5 June 2017 (UTC)[reply]

^ https://archive.org/details/introductionlac05mart

I would check to make sure that the incorrect spelling wasn't the attributed name from the publisher. If it was, then correcting it would introduce an error, making it more difficult to locate the sources. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 21:06, 5 June 2017 (UTC)[reply]

WP:AWB. 14.2.224.5 (talk) 01:21, 6 June 2017 (UTC)[reply]

Moved this thread to Village Pump (technical) (where I should have asked in the first place, sorry (but everybody was helpful, thanks again))darthbunk pakt dunft 23:52, 6 June 2017 (UTC)[reply]

June 6

Where is this icon located in Windows 10?

The following discussion is marked as answered. If you have a new comment, place it just below the box.

I tried searching in imageres.dll, shell32.dll and wmploc.dll using Resource Hacker. But couldn't find it there. I need a higher resolution (as much as possible) of this icon. Any help will be appreciated. --Joseph 03:42, 6 June 2017 (UTC)[reply]

@991joseph: Does http://primerecords.dk/Wikipedia/broken_thumbnail_icon.png help? I renamed a text file to jpg to make a broken image, viewed the folder in Windows 10, selected to view extra large icons, and took a screenshot. I made up the name "broken_thumbnail_icon" and don't know where the image is from. PrimeHunter (talk) 09:31, 6 June 2017 (UTC)[reply]

@PrimeHunter: Oh..! Hats off for the effort. Meawhile I got the answer. It's located in C:\Program Files\WindowsApps\Microsoft.Windows.Photos_17.425.10010.0_x64__8wekyb3d8bbwe\Assets\.--Joseph 10:46, 6 June 2017 (UTC)[reply]

June 8

windows 10 and annoying taskbar behaviour

hi all, another win 10 irritation ... on the taskbar, when I have eg. two different instances of firefox running, I can't get two different icons on the taskbar. I have to click the single icon, then it shows me two screens, then I have to click the right one. This irritates the heck out of me. How do I change it? Better, can I get back the whole vista taskbar, which has the title of the open window? Win 10 is mostly an improvement, but I worry that some weirdos have taken over the look and feel (Cortana etc). IBE (talk) 02:17, 8 June 2017 (UTC)[reply]

See if this helps. Look for Taskbar Buttons options under Taskbar properties (right mouse click on the Taskbar). manya (talk) 06:22, 8 June 2017 (UTC)[reply]

Excellent, should have done more googling first, sorry there ;(, otoh, I have been consuming so much time with so many related windows 10 things, that I was pretty much going mad. At least that's the excuse I'm using, cheers, IBE (talk) 06:28, 8 June 2017 (UTC)[reply]

docker layers - deleted files

I can see how docker can overlay "layers" of files if you add or change a file in a newer layer that one is seen. How does Docker manage if you remove a file in a later layer? -- Q Chris (talk) 09:27, 8 June 2017 (UTC)[reply]

"Each layer has an archive of the files which have been added, changed, or deleted relative to its parent layer" - so it uses a union mount ~~(or, as there can be many layers, a series of concentric union mounts).~~ -- Finlay McWalter··–·Talk 10:36, 8 June 2017 (UTC)[reply]

Hmm, on thinking about it, probably not concentric mounts, that's overcomplicating it. -- Finlay McWalter··–·Talk 11:54, 8 June 2017 (UTC)[reply]

As to the matter of deletion specifically, The Design and Implementation of the 4.4BSD Operating System by McKusick et al. (p236) has a nice explanation "The tricky part ... is handling the removal of files that reside in a lower layer. Since the lower layers cannot be modified, the only way to remove a file is to hide it by creating a whiteout directory entry in the top layer ... If the kernel finds a whiteout entry while searching for a name, the lookup is stopped and the 'no such file' error is returned." I think most subsequent union filesystem implementations work the same as the early BSD one described there. -- Finlay McWalter··–·Talk 10:46, 8 June 2017 (UTC)[reply]

June 9

”Internal Storage” memory¬1

How do you clean, or format the “Internal Storage” memory of a “Smart Phone”? 116.58.205.46 (talk) 05:28, 9 June 2017 (UTC)[reply]

It depends on what you mean by formatting, what kind of phone you have, and what lengths you're willing to go to. Try typing format <your phone model> into Google. See also iOS jailbreaking and Rooting (Android OS). Matt Deres (talk) 10:52, 9 June 2017 (UTC)[reply]

”Internal Storage” memory¬2

I wish to uninstall and re-install the Smart Phone, just like the way you do it on PC. What’s the process? 116.58.205.46 (talk) 05:28, 9 June 2017 (UTC)[reply]

You can try the factory reset which probably includes pressing a button for a long time at power up. Graeme Bartlett (talk) 12:02, 9 June 2017 (UTC)[reply]

Secure Connection

How do I ensure I have a secure connection from PC SHAREit to my Smart Phone SHAREit software? – Could a third party retrieve files while I’m transferring back and forth. 116.58.205.46 (talk) 05:28, 9 June 2017 (UTC)[reply]

Dongle to Smart Phone

I wish to use my PC internet connection securely on my Smart Phone. E.g., say I went on-line using my internet dongle on my PC, than instead of using the ‘webpage’ or “Google Play Store” on the PC, I wish to use the Smart Phone for it… 116.58.205.46 (talk) 05:28, 9 June 2017 (UTC)[reply]

By "dongle", are you referring to an cable? If not, what you are trying to do makes little sense. Your computer is using wifi to connect to, likely, a router. Your phone can connect directly to the router as well. Is the issue that you've forgotten the wifi password and you want to bypass getting it by using the existing connection on your computer? Then, you should be asking how to get the password from your router or your computer settings. 209.149.113.5 (talk) 12:45, 9 June 2017 (UTC)[reply]

Recent website and app design

What's the name of that new outlandish design and layout that is being introduced to many websites and apps? Samples: [1], [2], with typical switches. CSS3? I'm not sure it's the same adopted some time ago by YouTube, but looks like it. Brandmeister^talk 17:04, 9 June 2017 (UTC)[reply]

It doesn't look anything particular to me, why do you say it is new or outlandish? If it is new it is pretty crummy as it has a fixed layout rather than being fluid and so doesn't work on a smartphone nicely. Dmcq (talk) 18:35, 9 June 2017 (UTC)[reply]

It may look nice, but has been harder for me to use and get accustomed in one website and one app at least. Brandmeister^talk 19:17, 9 June 2017 (UTC)[reply]

Regex search in Notepad++ captures Non‑capturing groups. How do I stop it?

In Notepad++ (v.7.3.3 32-bit) (On Windows7 64-bit) When I search for the regular expression:
«(?:unwanted )word»
on the string:
«The first is an unwanted word»
Then Notepad++ captures (highlights):
«unwanted word»
instead of just capturing the: «word» that I want.

Q1: Why does Notepad++ capture regex non‑capturing groups («(?: … )») ?
Q2:And how do I turn off this behavior?
-- 176.11.91.179 (talk) 19:17, 9 June 2017 (UTC)[reply]

That is because "unwanted" is part of the overall match, which is accessible as \0 in the replace expression. The "(?:...)" is telling the regex engine not to save "unwanted" separately as \1. This is more apparent if you change your search expression to "(?:unwanted )(word)" and set the replacement expression to "\1". In this case, the entire match would be saved as \0, and "word" would be saved as "\1".

What you might be looking for is a look-behind zero-width assertion like "(?<=unwanted )word", which would match "word", but only if preceded by "unwanted ". -- Tom N talk/contrib

June 10

The AIM-9 Sidewinder guidance system

The Apollo Guidance Computer of 1966 was roughly as powerful as an Apple II of 1977.

The earliest AIM-9 Sidewinder infrared guided air-to air missile was first introduced in 1957. How good was its earliest computer and the 5-cell CdS IR sensor array?

I thought such a primitive weapon could only be launched withing visual distances from the enemy's tail. The controller probably could not take aerodynamics into its calculations. Maybe it was just an analog PID controller for proportional navigation built with very rough gravitational compensation (going up is tougher than going down). The missile certainly knows which way is up because it has fins and four rollerons. I don't think its IR seeker could measure the distance to the target. Looks like it could only provide a very rough target direction.

The solid rocket engine inside the missile could only provide seconds of thrust. When it dies, its thermal battery dies shortly after. Having very limited kinetic energy, it probably did not have many tries to adjust the fins to get to the enemy's tail. All its was able to do, I guess, was to get close to the enemy's tail (with just a few very imprecise tries) as possible and then let the proximity fuse determine when to detonate and hope for the best.

This crude design must have been statistically significantly better than an unguided rocket fired at the same conditions for the Pentagon to buy it. I wonder what was the lowest technological advancements to build a usable guided missile before we have today's computers and sensors that was good enough to replace machine guns and dumb rockets having nothing at all. -- Toytoy (talk) 03:19, 10 June 2017 (UTC)[reply]

[1] ttps://archive.org/details/introductionlac05mart

[D 1]