Episode 201: OPSEC!

Download the video! (21:44, 43MB)
The companion file! (51MB)

Nearly all colour laser printers leave a pattern of tiny yellow dots all over the paper. These dots contain information about the printer and perhaps also about the time and date of the print, the IP of your computer and who knows what else. These codes are in there for at least a decade and the EFF has complained in vain. Reality Winner got cought with these dots – but perhaps they would have found out about her a bit later without them.

The EFF has a dorky video about that.

I have a laser printer in my office at school. What does it tell about me? I research that with help of GIMP 2.9 – which looks terrific and has a lot of nice new stuff on board.

And of course you get to see some of these new features.

The companion file contains the scan of the Ordnungsmaßnahmenverordung in different resolutions and the XCF file with the revealed code. The last paragraph on the page gives me the right to take away your phone and hand it back to your parents after a reasonable time – if it beeps again in my class. (A lot of kids would prefer the cane over this….  😉 )

I forgot about the serial number of the printer – this will be updated soon.

The TOC:

00:00:00 Intro

00:00:50 Leaking from the NSA
00:01:35 Little yellow dots on laser print
00:03:00 Gimp 2.9 fired up
00:03:30 Search for the yellow dots
00:04:20 Colour Channels
00:06:00 Extract a colour component
00:06:40 Split view – new in filter dialogs
00:07:15 Searching for the pattern
00:07:55 New things in the layer dialog
00:08:30 Searching for the pattern
00:10:10 Crop tool
00:10:30 Measuring the pattern
00:11:35 Adding a precise grid
00:12:45 30 bytes of data in the yellow dots!
00:14:00 What’s not in the code?
00:15:00 Printing leaves traces
00:16:25 Blunder of “The Intercept”
00:17:00 Anonymising a scan with the threshold tool
00:18:30 The mono mixer for getting red back in
00:20:00 Return of the Minox for leakers?
00:21:00 We need a guide about OPSEC!
00:21:44 End of video

Meet the GIMP Video Podcast by Rolf Steinort is licensed under a Creative Commons Attribution 4.0 Unported License.
Permissions beyond the scope of this license may be available at https://meetthegimp.org.

Episode 198: Darktable revisited

Download the Video! (42:00, 80 MB)

No Companion File!

Watch at YouTube

darktable is an open source photography workflow application and RAW developer. A virtual lighttable and darkroom for photographers. It manages your digital negatives in a database, lets you view them through a zoomable lighttable and enables you to develop raw images and enhance them.”

I cant say it better than this bit from their page.

I had tested darktable in 2010 and found it promising – but stayed with f-spot and later Shotwell. But now I’ll switch to darktable.

These 42 minutes are a rigorously cut down version of my nearly 2 hours long walk through darktable – I was distracted so much by the endless modules and possibilities that I forgot the time. This will not be my last darktable video, I’ll try to focus a bit more on usable stuff in them. 😉

You can find Pascal’s videos at pcode.nl, you have to search a bit for them.

And here is a collection of darktable videos, recommended by our Bert (rayadagio).

The TOC

00:00:00 Start and book savings announcment
00:02:32 Darktable startup
00:03:50 Importing images and grouping them
00:06:10 Copying and moving images
00:09:00 XMP files
00:10:30 Tagging
00:11:35 Geotagging
00:15:00 Rating and marking images on the Zoomable lighttable
00:16:20 The manual
00:18:30 The darkroom
00:21:00 The interactive histogram
00:21:40 Undo with the history stack
00:22:20 Lots of modules
00:25:40 Cropping and rotating
00:27:00 Zooming in the darkroom
00:29:30 Non destructive editing
00:30:20 Levels and curves
00:32:30 Stacking curves (and other modules)
00:33:20 Color correction
00:34:20 Monochrome conversion with color filters
00:35:30 Correction lens errors and lots more modules
00:39:00 Exporting the image
00:42:00 EOF

Meet the GIMP Video Podcast by Rolf Steinort is licensed under a Creative Commons Attribution 4.0 Unported License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.