No-think link (redone)

When I first used ln, I expected the behavior of ln source link to work. But ln is slightly more complicated than that. While learning it from the beginning, I discovered it does not always resolve the path correctly; additionally, it doesn’t not error if the source is non-existence. I discovered that this was necessary because ln is designed to be versatile. So I understood that one would want links at times to be created that don’t exist yet, but it was unhelpful to me in the way that I felt ln should logically work, and the way that I wanted to use it.

Originally, I would do a link like this and it would be broken:

# ln -s ../dir/file dir/

I’ve attempted other links since then that too (of which I can’t remember now) would also be broken. So the way I discovered to do links correctly without doubt was to use whats called the fully-qualified or absolute path (i.e. a path defined from root [/]):

# ln -s /home/username/Document/file /home/username/Desktop/file

There’s a program called realpath that does this, so I wrote a wrapper script for it and it turned out to be pretty easy. The script resolves the absolute paths, verifies the existence of the source directory and link parent directory, and detects write permissions prompting sudo when needed. It works like this:

# lnk ~/Documents/Resumes/ ~/Desktop
‘/home/username/Documents/Resumes’ -> ‘/home/username/Desktop/Resumes’

By doing:

# lnk ~/Documents/Resumes/ ~/Desktop/Resumes-I-like
‘/home/username/Documents/Resumes’ -> ‘/home/username/Desktop/Resumes-I-like’

a specifically named link will be put on the Desktop.

# lnk /etc/fstab  ~  # or use ~/fstab-edit
‘/etc/fstab’ -> ‘/home/todd/fstab’

If trying to link to a write-protected directory:

# lnk /usr/share/vim/vim73/vimrc_example.vim /etc/vimrc
[sudo] password for $USER:
‘/usr/share/vim/vim73/vimrc_example.vim’ -> ‘/etc/vimrc’

An error message will appear if the source or link parent directory doesn’t exist:

Non-exist: .bashr

Limitations:

* The script will work for just about any instance with the exception of removable media where relative-paths would be better used.

Encode an Audio file to Video file

I wanted to convert an mp3 file to an mp4 or avi file because I wanted to be able to use it on my PS3 ( the PS3 has a basic audio player that doesn’t save position [ particularly troubling for large audiobooks ] ). This although is good for audio posting on youtube… I found a script by Jeremy Tharp that needed a bit of a tuneup (quoting parameters for file names with spaces, fixed exit status, better detection for the duration) and it works pretty good:

Handling display calibration

Though it is the expectation that a monitor is ready as soon as it is removed from the box, most monitors need to be calibrated. A much more vivid, detailed, true experience can become available after it is done that can be enjoyed and “feels right”. Calibrating a monitor correctly requires training of the eye so it initially can take a bit of work.

Hardware

All settings done to calibrate the monitor should be done on a hardware level (except for possibly gamma) as software solutions almost never adjust the image truely. Before beginning, have the monitor on for about ten minutes as it can take the lamp this long to warm up and represent accurate values.

Gamma

Gamma correction is the adjustment of mid-tone luminosity. It is used to compensate for the non-linear relationship between the input signal and the luminance of a monitor. Televisions, computers, and the internet use a gamma of 2.2 as a standard so monitors set to this to be able to correctly display output. Most monitors default to the 2.2 standard but some monitors deviate and therefore hardware and/or software gamma correction is required. A high gamma will look glowy and a low gamma will appear errie and dark.

Alternate

Gamma test and Alternate

There is likely a gamma setting on the monitor if it needs to be adjusted. If there isn’t, or for further adjustment, a software solution is available. The first software solution would be to use the EDID data built-in to the monitor of most modern-day computers. It contains details about the monitor including gamma correction. The Desktop Environment may have the ability to grab the EDID and save it as an ICC profile (GNOME does), otherwise a program like Quickgamma in windows will do. If the monitor does not have EDID information, Quickgamma also has the ability to manually-calibrate the gamma and create an ICC profile from that; it saves the ICC profiles to C:\Windows\System32\spool\drivers\color.

To load an ICC profile put it in ~/.local/share/icc/ and see if your Desktop Environment supports it. If it does not, a good program that can load them is xcalib.

In the image, lightly squint the eyes (or step away) to find the match where gamma blends with the background.

Contrast

Contrast defines the tonality of an image. Tonality is the gradient leveling from light to dark. With a high contrast the light and dark extremes become “crushed” or “blended” together, a low contrast the and images will appear flat. Contrast is also reflects the white-level (the brightness of white) of the monitor; contrast levels are often defined when buying a monitor because they will tell how bright the lamp is.

In this image, turn up the contrast to maximum and the reduce until all whites become distinct and the first block is just barely discernable.

Brightness

Brightness is better-referred to as black-level as it defines the “brightness of black”, or how bright darkness goes. Black is “black” or will be just above the black of the monitor if turned off. Adjust the image so that the left box just barely discernable. It may be necessary to go back and forth between contrast and brightness until the right balance is met.

Note: Discernability of the lightest light boxes and the blackest dark boxes should be possible on a modern monitor; however, it should be known that some monitors are unable to reproduce them.

Color balance

For color the first thing to do is adjust saturation. Saturation is the total amount of color the monitor will display. Too much saturation and images will be heavy with color, too little and they will appear faded. On some monitors the setting will be called Color, on others it will be Saturation, and on others it will be controled through an accumulative adjustment of the Red, Green, and Blue channels. Use the images below to determine saturation. Skin tone is a good indicator for this; however, also look at the colors on the color wheel as “bleeding” will at times occur when over-saturation occurs.

To adjust the color balance, also use the images below with skin tone as a reference. Do one color at a time, go back and forth, back and forth, until it feels right. When doing this be careful not to strain the eye too much as eye fatigue effects colorreception. Take a break after a little bit (get up and strech, make lunch…) and come back and you’ll immediately see, “Ah, the image is too red” or “Ah, the image is too blue”… The base colors Red, Green, and Blue also have complementary colors or complmentary light, the opposite of Red is Cyan, Green Magenta, and Blue is Yellow. If an image has too much Magenta it will need more Green. Again look at the skin tone (the gray in the first image works good). This is where the trained eye comes in. With practive eventually color bents will become discernable. Once it is achieved, the discovery of a well defined monitor can be begun to be enjoyed.

Skin-tone, gray background

Skin-tone, gray background

Light skin-tone

Light skin-tone

Darker skin-tone

Darker skin-tone

Resources

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Firefox: Defining font type and size

roystonlodge_Alternate_Mozilla_Browser_Icon

What a professional typesetter knows is the importance of a good font. For centuries typesetters have developed fonts that provide ease of reading that we see in most books today. Having the text look good in the web browser is necessary, choosing the right type and size can make a big difference to how well we read, especially if used quite a bit.

font installation

To make a web page feel right (as was designer had in mind) the fonts should be on your system that a page requires. On many Linux systems the only webfonts installed are the DejaVu fonts which are also the common default Serif, Sans-serif and Monospace fonts for most distros. Adding missing fonts will make a difference to the pages’ look and adds a lot of nice touches to pages that one didn’t know one was missing before. This addon can tell from selected text that type of font that is required on a webpage and what its size is. Basically though most sites still define their fonts as Arial, or sometimes, Verdana, or Georgia that are a part of Microsoft’s core fonts. A few though define theirs with Apple fonts, and a few less with others. These are the most popular webfont groups. To install them (on Arch Linux):

pm i ttf-ms-fonts ttf-vista-fonts ttf-mac-fonts ttf-liberation ttf-google-fonts-distilled ttf-freefont ttf-droid

With MS Core Fonts installed (and a few others) most people will notice a noticably better browser experience becoming available.

Font size

To get a good idea on font size, look at a hardback books fonts and make it about 20% bigger as books are generally two feet away and monitor are a bit more. Also making the different font types about the same height is a good practice as this helps with what is called scanning-expectation (where one expects a font to be when tracking it).

Font type

Being able to select a font that appeals to the users taste is really nice. In Firefox’s settings one can define a preferred font of Serif, Sans-serif, and Monospace. However, it should be known though that many sites still force their own font type and size. The good news is that a greater number of sites are using generic Serif, and Sans-serif, and Monospace definitions so personalizing the look of fonts on a greater scale in the future should be possible. When choosing a font type, pick one depending on what is easy on the eyes rather than one that grabs ones attention (based on readability is what usually works best).

Font tests

Here is a basic test of what Firefox’s base-defined font types and sizes look like:

Font test: Type and size (based defined). (click to view)

Font test: Type and size (based defined). (click to view)

Here are what a few of the basic webfont groups look like:

Font test: Common webfonts group 1. (click to view)

Font test: Common webfonts group 1. (click to view)

Font test: Common webfonts group 2. (click to view)

Font test: Common webfonts group 2. (click to view)

What did I choose?

After adding all the new fonts and testing all the varied ones, surprisingly I found out that overall the MS core fonts were the best. They read beautifully and scale well and just are a pleasure to look at. Ultimately I came up with these settings (font sizes are picked based on a 102 DPI monitor):

Font type Font size
Serif Droid Serif 15
Sans-serif Arial 15
Monospace DejaVu Sans Mono 14
Minimum 11

And it feels great, wouldn’t trade DejaVu Sans Mono for anything. Also I should note that rather than just defining fonts to Firefox, I choose to define my system Serif, Sans-serif, and Monospace fonts (via font config) to point my preferred choices (that is, I don’t need to define them in Firefox). Here is my fontconfig config and it includes my choice of good font to best font in respective order: link.

For GNOME the fonts sizes are:

Default 12
Document 12
Monospace 11
Window Title 13

What they look like:

Font type and size

Font type and size

Common webfont groups 1

Common webfont groups 1

Desktop

Desktop

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External monitor as Discrete

I use my laptop primarly at home with an external monitor as discrete, meaning that I have the laptop monitor turned off and I only use it. At times this is also called a dedicated monitor. GNOME can be set to disable the laptop monitor and enable the external but it wasn’t able to hotplug the monitor after I returned the laptop, and at times wouldn’t do so after resuming from sleep. Also in the proccess I discovered that the X.org server DPI setting wasn’t being done correctly and that GNOME’s text scaling needed to be adjusted. So I decided to do it in a script and it turned out to be pretty easy.

I wrote the basic script that toggles monitors depending if the external monitor is present, then it detects correct physical size dimension of the screen so the the correct DPI can be set. After this, I added a startup script (.desktop file), a pm-utils script to runafter resuming, and a udev script to detect andset the monitor when plugged in. The udev rule is generic but appears to be working for a lot of people, it relys on Kernel Mode setting (KMS) so doesn’t work for me wiht the catalyst driver, but every thing else works great. I put it on github for any who like to look at it.

The bash script cannot be used right away instead a couple bit will need to be directed:

 The package cannot be installed directly and be expected to work, some edits
 will need to be made.  First, in the resume script '80_discretemon' a username 
 will need to be defined; next, the monitor names will need to be defined as
 created by the driver in 'discretemon'.

Also, the monitors can be defined in xorg.conf but the fix for after resume from sleep, remains.

Section "Monitor"
  Identifier  "0-LVDS"
  Option      "VendorName" "ATI Proprietary Driver"
  Option      "ModelName"  "Acer Aspire Laptop Screen"
  Option      "DPMS" "true"
  Option      "TargetRefresh" "60"
  Option      "Position" "0 0"
  Option      "Rotate" "normal"
  Option      "Disable" "true"
  DisplaySize  344 194 # only works with xrandr disabled.

EndSection

Section "Monitor"
  Identifier  "0-DFP1"
  Option      "VendorName" "ATI Proprietary Driver"
  Option      "ModelName"  "Samsung SyncMaster SA350"
  Option      "DPMS" "true"
  Option      "PreferredMode" "1920x1080"
  Option      "TargetRefresh" "60"
  Option      "Position" "0 0"
  Option      "Rotate" "normal"
  Option      "Disable" "false"
  DisplaySize  476 268 # only works with xrandr disabled.
  Option      "DPI" "102 x 102"
EndSection
2 Comments

Catalyst Driver, a Journey Taken… Better than I’d Known

I previously read about (a good number of times) people not having the best experiences with AMD’s proprietary driver. However, with my new laptop I decided that no matter how much I love the open-source driver (bought it because AMD opened the specs to it), that realistically it would take a few years before I’d be able to play games with it. The AMD/ATI website says 7xxxM series is supported so I decided to try it.

Prepare for Installing Catalyst

Removed open-source Radeon driver options, commented /etc/X11/xorg.conf.d/20-radeon.conf.

Installing Catalyst Driver

Using Vi0l0’s excellent catalyst repository, I added it to /etc/pacman.conf:

[catalyst] Server = http://catalyst.apocalypsus.net/repo/catalyst/$arch

Add Vi0l0 key:

sudo pacman-key -r          NUM
sudo pacman-key --lsign-key NUM

Installed (using pacman shortcuts script (pm):

pm y
pm i linux-headers catalyst-hook catalyst-utils lib32-catalyst-utils

Using catalyst-hook here to have the module put into initramfs when kernel versions areupgraded (provides catalyst driver).

X.org Server-Configuration

sudo aticonfig --initial 

Added module to load at boot:

echo '# Load AMD Catalyst driver
fglrx' | sudo tee /etc/modules-load.d/fglrx.conf

Disabled Mode Setting: Added GRUB_CMDLINE_LINUX="nomodeset" (for GRUB2) to /etc/default/grub), then:

sudo grub-mkconfig -o /boot/grub/grub.cfg

Testing

Reboot, and driver loaded properly (lsmod | grep fglrx), and direct rendering is enabled (glxinfo | grep direct).

Configuring Display

Created root .desktop for ATI Catylyst Control Center:

cp /usr/share/applications/amdcccle.desktop ~/.local/share/applications/
sed -i 's/Exec=amdcccle/Exec=gksudo amdcccle/' ~/.local/share/applications/amdcccle.desktop
chmod +x ~/.local/share/applications/amdcccle.desktop

Color

  • Color Temperature: Use display’s settings

Display Manager

  • Selected down arrow for both monitors to change to correct settings.

Logout/Login: Gnome 3 crash, extensions disabled
Login: Monitor settings lost, both on lower resolution (open-source radeon driver and catalyst define monitors differently so Gnome using xrandr flubs the first time after.

DTV

  • Pixel Format: RGB 4:4:4 (Full RGB)
  • Adjustments: Overscan 0%

Switchable Graphics

Catalyst driver does not recognize discrete GPU properly, thinks integrated GPU is discrete GPU:

Show GPUs:

aticonfig --list-adapters
* 0. 00:01.0 AMD Radeon HD 6520G          # * Default
  1. 01:00.0 AMD Radeon HD 7600M Series

But…:

aticonfig --px-list
PowerXpress: Discrete GPU is active (High-Performance mode).

I tried using sudo aticonfig --px-igpu to switch to integrated to see if it would switch but got an X.org server hang. Also tried sudo aticonfig --px-dgpu to see if aticonfig --px-list was in error but no luck. Tried using discrete GPU BusID (BusID "PCI:1:0:0") in xorg.conf but that didn’t work either. The catalyst driver doesn’t properly recognize the 7670M GPU as discrete GPU. Entered bug.

GNOME bug

When I first started with GNOME mouse clicks would miss at times and sometimes keypresses did too, I added export CLUTTER_VBLANK=none to ~/.bash_profile and it fixed this. Oddly, I commented it later because I thought it might be related to another bug (it was not) and forgot to enable it again, but I haven’t seen the problem since.

Conclusion

Hard to believe there is not official AMD Catalyst bugzilla (odd how their website points to the unofficial one) so I’m a bit worried about the near future but think all will be fine.

The driver works good. I’m getting a consistent 50fps on Urban Terror and tried Doom and it looks pretty good. Disappointed about not being able to use the discrete GPU, would have been nice. Gonna keep using catalyst, its working good.

Here’s a script i built called gpuswitch I plan to use when gaming later. Night.

Resources

3 Comments

The Beauty of rsync and Backup Script

rsync is a command-line tool used to copy/clone files (“fast incremental file transfer“). It is a great, simple backup tool. The basic rsync command is this:

rsync -a src dest_dir

Where src is the original directory or file and dest_dir is the destination directory. Because rsync does incremental backups it only adds the file to the dest if it has been updated from the original backup.

rsync -axS src dest_dir

This is the command I use. This command can be used to backup just about anything! The options:

  • -a means archive mode which basically means to preserve the file “as is” (same permissions…)
  • -x means not to cross file systems boundaries
  • -S means to handle sparse files efficiently
  • -v option (verbose) can be used to print what rsync is doing

An important note about rsync: when src is a directory a trailing slash (/) tells rsync to copy the “contents” of the directory:

rsync -axS src_dir/ dest_dir
ls -1 dest_dir/
 file1
 file2

Without a trailing slash:

rsync -axS src_dir dest_dir
ls -1 dest_dir
 src_dir

rsync can also use file-lists containing paths of directories and files, to both include and exclude them for backup:

sudo rsync -axS --files-from="incl_file.txt" --exclude-from="excl_file.txt" src_dir dst_dir

src_dir will have to be specified and will have to be relative to paths in the file list:

cat incl_file.txt
Desktop/
rsync -axS --files-from="incl_file.txt" --exclude-from="excl_file.txt" /home/user/ dst_dir

rsync can also remove files from the dest_dir with the --delete option, so files that get added to the exclude file or taken out of the include file will removed from dest_dir.

rsync -axS --delete-excluded --files-from="incl_file.txt" --exclude-from="excl_file.txt" /home/user/ dst_dir

Backup Script

I use rsync to backup my system configurations and /home/ to make reinstalling easy. I created the script to remember the command to use, but to also easily add to the include and exclude files:

bcksysc i /etc/hostname 
 Added "/etc/hostname" to bcksysc-inc.txt include file.

Syntax:

bcksysc 
 bcksysc  - backup configurations
 i - add to the include list a file or folder
 e - add to the exclude list a file or folder
 c - create backup

Here’s the script all that needs to be done is to change the Parent Destination Directory (for backing up /home/ I copied the script to bckhome, changed the type to home and added /home/ to the include file):

So my destination directory looks like this:

ls -1 /run/media/todd/Backup/rsync/
 ...
 aspire_2012-08-31_sysc
 aspire_2012-08-31_home
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