Month: April 2016

Lossless JPEG rotation

JPEG is a lossy format, and naive rotation results in a loss of quality. JPEG does allow some lossless operations, such as rotation by 90 degrees and flipping, on the basic blocks (MCUs) that compromise the image. It also allows re-arranging those blocks. Using this lossless operation, it is possible to preform a lossless JPEG rotation. To do so, the rotated image mus meet some basic criteria like having it size a multiple of the MCU size (usually 16×16).

Not all programs preform a lossless JPEG rotation, so it is useful to be aware which does. I check a couple of commonly used program to see if they indeed preform lossless rotation. The testing procedure was:

  1. Start with the original JPEG photo.
  2. Rotate it once to the right using each program.
  3. Rotate a copy of the rotated photo back to the right using the same program.
  4. Compare using ImageMagick (compare -metric ae) the results.

Results

Gnome’s Image Viewer 3.14.1 is lossless
Digikam (4.4.0) is lossless, however rotating with Digikam’s Image Editor is lossy.
Shotwell (0.20.1) does lossy rotation.

en_IL: English locale for Israel

Update: The new locale was committed to glibc and should be part of glibc-2.24.

Most Israelis are literate in English, and for a large percentage of them, English is also the preferred language when it comes to computers. They prefer English, as it solves right-to-left issues and general inconsistencies (it might be annoying when some programs are translated ands some not). The downside is, that currently, the existing English locales are not suitable for Israel, as there are cultural differences:

  • American English spelling is more common in Israel.
  • The metric system is used, along with the relevant paper sizes (“A4” instead of Letter).
  • Dates are written in dd/mm/YYYY format, unlike in the USA.
  • The first day of week, and also the first workday is Sunday.
  • The currency used is ILS (₪).

So, up until now users had to choose locales such as en_US or en_GB and compromise on some stuff. To solve this issue, and create a truly suitable English locale for Israel, I wrote a localedef file for the en_IL locale.

To install the new locale, copy the en_IL file from the gist below and place under /usr/share/i18n/locales/en_IL (no extension). Next

# echo "en_IL.UTF-8 UTF-8" >> /usr/local/share/i18n/SUPPORTED

Now, complete the installation by running dpkg-reconfigure locales and enable en_IL.UTF-8 from the list, and set it as the default locale.


comment_char %
escape_char /
% This file is part of the GNU C Library and contains locale data.
% The Free Software Foundation does not claim any copyright interest
% in the locale data contained in this file. The foregoing does not
% affect the license of the GNU C Library as a whole. It does not
% exempt you from the conditions of the license if your use would
% otherwise be governed by that license.
% Locale for English locale in Israel
% Contributed by Guy Rutenberg <guyrutenberg@gmail.com>, 2016
LC_IDENTIFICATION
title "English locale for Israel"
source "Free Software Foundation, Inc."
address "http:////www.gnu.org//software//libc//"
contact ""
email "bug-glibc-locales@gnu.org"
tel ""
fax ""
language "English"
territory "Israel"
revision "1.1"
date "2016-04-19"
%
category "i18n:2012";LC_IDENTIFICATION
category "i18n:2012";LC_CTYPE
category "i18n:2012";LC_COLLATE
category "i18n:2012";LC_TIME
category "i18n:2012";LC_NUMERIC
category "i18n:2012";LC_MONETARY
category "i18n:2012";LC_MESSAGES
category "i18n:2012";LC_PAPER
category "i18n:2012";LC_NAME
category "i18n:2012";LC_ADDRESS
category "i18n:2012";LC_TELEPHONE
category "i18n:2012";LC_MEASUREMENT
END LC_IDENTIFICATION
LC_CTYPE
copy "en_GB"
END LC_CTYPE
LC_COLLATE
copy "en_GB"
END LC_COLLATE
LC_MONETARY
copy "he_IL"
END LC_MONETARY
LC_NUMERIC
copy "he_IL"
END LC_NUMERIC
LC_TIME
abday "<U0053><U0075><U006E>";"<U004D><U006F><U006E>";/
"<U0054><U0075><U0065>";"<U0057><U0065><U0064>";/
"<U0054><U0068><U0075>";"<U0046><U0072><U0069>";/
"<U0053><U0061><U0074>"
day "<U0053><U0075><U006E><U0064><U0061><U0079>";/
"<U004D><U006F><U006E><U0064><U0061><U0079>";/
"<U0054><U0075><U0065><U0073><U0064><U0061><U0079>";/
"<U0057><U0065><U0064><U006E><U0065><U0073><U0064><U0061><U0079>";/
"<U0054><U0068><U0075><U0072><U0073><U0064><U0061><U0079>";/
"<U0046><U0072><U0069><U0064><U0061><U0079>";/
"<U0053><U0061><U0074><U0075><U0072><U0064><U0061><U0079>"
abmon "<U004A><U0061><U006E>";"<U0046><U0065><U0062>";/
"<U004D><U0061><U0072>";"<U0041><U0070><U0072>";/
"<U004D><U0061><U0079>";"<U004A><U0075><U006E>";/
"<U004A><U0075><U006C>";"<U0041><U0075><U0067>";/
"<U0053><U0065><U0070>";"<U004F><U0063><U0074>";/
"<U004E><U006F><U0076>";"<U0044><U0065><U0063>"
mon "<U004A><U0061><U006E><U0075><U0061><U0072><U0079>";/
"<U0046><U0065><U0062><U0072><U0075><U0061><U0072><U0079>";/
"<U004D><U0061><U0072><U0063><U0068>";/
"<U0041><U0070><U0072><U0069><U006C>";/
"<U004D><U0061><U0079>";/
"<U004A><U0075><U006E><U0065>";/
"<U004A><U0075><U006C><U0079>";/
"<U0041><U0075><U0067><U0075><U0073><U0074>";/
"<U0053><U0065><U0070><U0074><U0065><U006D><U0062><U0065><U0072>";/
"<U004F><U0063><U0074><U006F><U0062><U0065><U0072>";/
"<U004E><U006F><U0076><U0065><U006D><U0062><U0065><U0072>";/
"<U0044><U0065><U0063><U0065><U006D><U0062><U0065><U0072>"
d_t_fmt "<U0025><U0061><U0020><U0025><U0064><U0020><U0025><U0062><U0020><U0025><U0059><U0020><U0025><U0054><U0020><U0025><U005A>"
d_fmt "<U0025><U0064><U002F><U0025><U006D><U002F><U0025><U0079>"
t_fmt "<U0025><U0054>"
am_pm "";"" % 24-hour clock is used
t_fmt_ampm ""
date_fmt "<U0025><U0061><U0020><U0025><U0065><U0020><U0025><U0062>/
<U0020><U0025><U0048><U003A><U0025><U004D><U003A><U0025><U0053><U0020>/
<U0025><U005A><U0020><U0025><U0059>"
week 7;19971130;1
% In Israel Sunday is a workday.
first_workday 1
END LC_TIME
LC_MESSAGES
copy "en_US"
END LC_MESSAGES
LC_PAPER
copy "he_IL"
END LC_PAPER
LC_NAME
copy "en_US"
END LC_NAME
LC_ADDRESS
postal_fmt "<U0025><U0066><U0025><U004E><U0025><U0061><U0025><U004E>/
<U0025><U0064><U0025><U004E><U0025><U0062><U0025><U004E><U0025><U0073>/
<U0020><U0025><U0068><U0020><U0025><U0065><U0020><U0025><U0072><U0025>/
<U004E><U0025><U007A><U0020><U0025><U0054><U0025>/
<U004E><U0025><U0063><U0025><U004E>"
country_name "<U0049><U0073><U0072><U0061><U0065><U006C>"
country_post "<U0049><U0053><U0052>"
country_ab2 "<U0049><U004C>"
country_ab3 "<U0049><U0053><U0052>"
country_num 376
country_car "<U0049><U004C>"
lang_name "<U0045><U006E><U0067><U006C><U0069><U0073><U0068>"
lang_ab "<U0065><U006E>"
lang_term "<U0065><U006E><U0067>"
lang_lib "<U0065><U006E><U0067>"
END LC_ADDRESS
LC_TELEPHONE
copy "he_IL"
END LC_TELEPHONE
LC_MEASUREMENT
copy "he_IL"
END LC_MEASUREMENT

view raw

en_IL

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