Commands by bhinesley (1)

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Make a thumbnail image of first page of a PDF.
convert is included in ImageMagick. Don't forget the [X] (where X is the page number). [0] is the first page of the PDF.

Update Ogg Vorbis file comments
The "vorbiscomment" utility lets you update information such as artist names and song and album tags in an Ogg Vorbis file. You can use this command to fix any mistakes that were made when ripping an album.

Show current working directory of a process

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

mean color of an image
You can get the mean value for the colours in an image. Then you can determine, in general, how dark or bright is the image and run some other actions based on that. I'll recommend to readjust the brightness of the images using +sigmoidal-contrast option of imagemagick convert command.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Calculate days on which Friday the 13th occurs
Simply change the years listed in the first seq, and it will print out all the months in that span of years that have Friday the 13ths in them.

List upcoming events on google calendar
Requires googlecl (http://code.google.com/p/googlecl/) Even better when you wrap this in a script and allow the --date=STRING to be $1. Then you can type: whatson "next Thursday" The date string for UNIX date is very flexible. You can also add --cal "[regex]" to the end for multiple calendars.

Retrieve the size of a file on a server
- Where $URL is the URL of the file. - Replace the $2 by $3 at the end to get a human-readable size. Credits to svanberg @ ArchLinux forums for original idea. Edit: Replaced command with better version by FRUiT. (removed unnecessary grep)

Downsample mp3s to 128K
This will lower the quality of mp3 files, but is necessary to play them on some mobile devices.

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