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March 11

How do I use the camera in my table-top computer?

I have a table top computer "Inspiron One" from DELL. I do not know the model number. It has the computer integrated into the large display screen with two feet in front and one in back. The keyboard and mouse are blue-tooth devices (i.e. they use radio rather than wires to talk to the computer). I can see that the screen has a camera lens at the top. When we first got it, the person who installed the computer was able to use Skype to talk to other people. So I presume that the camera worked with Skype at that time. However, I have not been using Skype and the software appears to be obsolete at this time. I would like to be able to use the camera to take pictures of myself and other people who visit here for possible use on Facebook, but I do not know how to do that. I have not been able to find any instructions on how to use this camera. Does anyone know where to look for them? Thank you. JRSpriggs (talk) 05:15, 11 March 2014 (UTC)[reply]

I don't know what software your computer may have come with, but there are plenty of photo-taking apps. This one [1] has some silly features, but will also just take standard photos. Google /windows photobooth app/ for other examples. (PS I wouldn't say Skype is obsolete, but your installed version may not be the latest version. Check in the Skype app for a "software update") SemanticMantis (talk) 16:19, 11 March 2014 (UTC)[reply]

manual. 70.174.141.142 (talk) 20:48, 11 March 2014 (UTC)[reply]

To SemanticMantis: Thank you. The program SNAP seems to be just what I wanted. Also, I got the Skype update. So now, Secunia says that my computer is 100% up to date. JRSpriggs (talk) 09:30, 12 March 2014 (UTC)[reply]

Word font problem on the computer

This is from China. The question is what's the difference between the word font AvenirLTStd-Black and Avenir-Black? And what's the LTStd stand for?Tiankong411 (talk) 06:39, 11 March 2014 (UTC)[reply]

Font names often include an abbreviation of the name of the foundry; in this case, LT is for Linotype (Mergenthaler Linotype Company). See Avenir (typeface) and the Adobe page. -- Gadget850^talk 10:12, 11 March 2014 (UTC)[reply]

In olden times the foundry name came first (ITC Garamond, Monotype Corsiva) but a suffix makes more sense for a computer menu. —Tamfang (talk) 22:16, 11 March 2014 (UTC)[reply]

Probably you have versions of Avenir from different publishers. Look out for small differences in size (letter height), weight (stroke thickness) and spacing. —Tamfang (talk) 22:19, 11 March 2014 (UTC)[reply]

extracting orientation information via libjpeg.

Like many people, I use libjpeg for reading JPEG images into my C++ code. I've noticed that it doesn't seem to take note of the EXIF flags that specify the orientation of the image. I can't seem to find a way within libjpeg to either tell it to pay attention to the flag and load the image the right way up...or to read the flag myself and re-order the data.

Since the documentation of libjpeg is kinda sparse, I'm having a hard time figuring out how to do this.

Help! SteveBaker (talk) 20:57, 11 March 2014 (UTC)[reply]

As far as I know you have to use an EXIF metadata library like libexif, read the "Orientation" entry yourself, and then handle all the cases with your own graphics library. If I understand it correctly there are four rotation options (0, 90, 180, 270) and an additional bit for horizontal mirror and another for vertical mirror. This GIThub has sample images for various orientation settings, so you can test your code. Some higher level graphics library, like libmagick, can take care of this automagically. -- Finlay McWalterჷTalk 21:25, 11 March 2014 (UTC)[reply]

If you don't want to depend on a full EXIF library, you could adapt the code from jpegexiforient. -- BenRG (talk) 22:26, 11 March 2014 (UTC)[reply]

I wrote some sample (C99) code using libexif:

example code

The following discussion has been closed. Please do not modify it.

#include <stdio.h>
#include <libexif/exif-data.h>

static void show_orientation(const char* filename){
  printf("%-50s ", filename);

  ExifData * exif_data_ptr = exif_data_new_from_file(filename);
  if(!exif_data_ptr){
    puts("error reading EXIF");
    return;
  }

  ExifEntry * orientation_entry_ptr = exif_content_get_entry(exif_data_ptr->ifd[EXIF_IFD_0],
							     EXIF_TAG_ORIENTATION);

  if(!orientation_entry_ptr){
    puts("no data");
    exif_data_unref(exif_data_ptr);
    return;
  }

  // see description of orientation data int16u at 0x0112 in:
  //   http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/EXIF.html
  printf("0x%02x ", orientation_entry_ptr->data[1]); // lsbyte of int16

  // libexif has code to pretty-print tag values for human consumption
  char buffer[64];
  if (exif_entry_get_value(orientation_entry_ptr, buffer, sizeof(buffer))){
    puts(buffer);
  }
  else {
    puts("");
  }

  exif_data_unref(exif_data_ptr);
}

int main(int argc, const char** argv) {
  for(int i=1; i< argc; i++) {
    show_orientation(argv[i]);
  }

  return 0;
}

-- Finlay McWalterჷTalk 22:38, 11 March 2014 (UTC)[reply]

FYI, this posting (which is where I nicked the github link) has a summary of orientation support in various online services - suggesting quite a few don't do a stellar job. -- Finlay McWalterჷTalk 22:44, 11 March 2014 (UTC)[reply]

My page on exif support from c# might be of use? [2]--Phil Holmes (talk) 15:42, 12 March 2014 (UTC)[reply]

Why has wikipedia loaded so slow for the last 10 days?

I access the internet from two different Verizon DSL accounts in the NE US. Forthe last 10 days, between ~6PM and midnight the connection to Wikipedia, and only Wikipedia, over either account, in two different states, has been incredibly slow, often freezing entirely. This is the case on two different computers, using three different browsers. No other site is slowed or freezes. Could this be an issue with Wikipedia, or something to do with the recent net neutrality ruling? I am confounded. Thanks. μηδείς (talk) 22:45, 11 March 2014 (UTC)[reply]

As I understand it, the server team can throttle back page delivery by IP address. It's possible... based on the comments of others at the talk page, and your ongoing behavior.... that someone has put in a request to slow down your chat capacity. Just sayin'. 193.169.86.13 (talk) 19:40, 20 March 2014 (UTC)[reply]

off topic OR
The following discussion has been closed. Please do not modify it.
They are running a donation campaign right now. They want to make you aware that they need the money to make things run smoothly. OsmanRF34 (talk) 01:46, 12 March 2014 (UTC)[reply] Can we please get some serious, reference based-answers? μηδείς (talk) 03:07, 12 March 2014 (UTC)[reply]

There seems to be some issue noted by admins and others affecting the NE US for the last week, see the two discussions at the teahouse. μηδείς (talk) 06:26, 12 March 2014 (UTC)[reply]

Not just the NE US. I've had exactly the same problem as you describe, over the same period. Today, finally, it seems a lot better. -- Jack of Oz ^{[pleasantries]} 07:22, 12 March 2014 (UTC)[reply]

Backdoor (computing)

Our article on Backdoor (computing) could use some attention by our more technically savvy editors. Please add it to your watchlist. Thanks! A Quest For Knowledge (talk) 23:10, 11 March 2014 (UTC)[reply]

Wikipedia:Reference desk/Archives/Computing/2014 March 11

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