First bash script coming up, I’ll explain the best I can: I have a set of images that are all square: w=h. I want to create an image of each image with a label on top,using the filename as the label (without the extension), with a white background, ending up with a 200×250 image with the same name as the original but with “-tab” added. IM will by default squeeze the font size so that the text label always fits. Continue reading
The ability to combine a set of images into one image in a variety of ways, essentially replicates the contact sheets of old. Here are a few ways to create a montage. It works best when all the images are the same height and width. IM does not understand page sizes, and will just create a simple image, regardless of the number of images, you can tell IM which images to use though. It also makes sense when testing and creating montages to save the output to a different directory, otherwise your montages will be included in the next iteration! Continue reading
Imagemagick (IM) is brilliant! If you want to do something to an image, Imagemagick can do it! Works on Linux and Windows. Can be scripted. Just use Imagemagick for your image manipulation needs.
Advert over. This and subsequent posts will serve as a reference for me, but also to show what imagemagick can do. Other than one liners, there will likely also be some bash scripting. I have also littered these posts with links to the IM documentation for all the features available with each of the actions. Continue reading
It is a disgrace really! I have has this running on an ancient laptop for over three years non stop, and not written it up, even failed to write it up on #! Crunchbang forums, where I got all the help from mrpeachy, Sector11, dk75 and others. Time to put that to rights. What is different about this “one”, you ask? Well, we have two conkys running, they are both in the background, so you still have a fully functional PC if you want to use it, you get sexy rounded corners on your image and a nice big digital purple clock.
Don’t know / can’t remember exactly what happened but for some reason my proprietary Nvidia driver stopped working, I lost OpenGL, and with that a lot of functionality on the desktop. After living with it for a couple of months, and there are many different solutions to doing it, I finally got around to sorting it out like this: Continue reading
Just a few tips and tricks for either creating or modifying pdfs under linux.
You will need to have ghostscript, imagemagick and pdftk installed.
A cool little command line or two.
Say you have a remote machine that you can ssh into, it is running an X server, and you want to take a screenshot of what is on screen. You will need imagemagick installed on the remote machine for the import command to work.
1. After you have ssh’d in:
DISPLAY=:0.0 import -window root /tmp/shot.png
This will save the screenshot to the remote machine’s tmp folder. You will need to scp across to get it!
2. Before ssh’ing
ssh user@remote-host "DISPLAY=:0.0 import -window root -format png -" | display -format png -
Replace user@remote-host with your details. The image will appear on your PC, you can then save it as required.
Both very cool
You setup a powerpoint presentation on your normal work machine, the encodes you did in mp4 worked just fine in the presentation. Save out to a stick and take it to the machine (an all in one touch screen 65″ with powerpoint viewer only) and all you see is a black screen where your video should be.
Scoured the interweb and tried three different encoding solutions, all of which resulted in a black screen.
I then upgraded the powerpoint viewer on the display machine from 2007 to 2010 (or the latest one I could find on the Microsoft pages). Bingo, the video started working.
Here is the encode I used which worked best, allowing proper full screen video, no black bars, etc.
ffmpeg -i input.mpg -q:v 4 -c:v wmv2 -c:a wmav2 -b:a 128k output.avi
Another solution to digital signage, this time using Google Slides and Chromium (or Chrome) in Kiosk mode.
I am using the base of a linux install (Crunchbang) and Chromium, but the basics transfer across to Chrome and other OS platforms with some tweaking.
- Kiosk Syntax
- The Google Slides Toolbar or Transport
- Web Page Presentation
- Updating the Slides
- Sharing the Slides
- Locking Down if keyboard/touchscreen in use
Am grateful for the work done by Mark Pajak at Bristol Museums on setting up Chrome/Chromium in kiosk mode, and to Google Slides users on the google groups forums and good old StackOverflow for other snippets.
I have a penchant for making full screen slideshows with a clock on them