fbi – linux framebuffer imageviewer

I was embarrassed to discover that the ever-popular dlfb “green screen” is broken in subtle ways by the new defio support. So for now with this new driver, DL devices may up with what appears to be gibberish. I didn’t notice, because my test config launches X on the DisplayLink device immediately.

In the absence of a working X setup, and until the draw-during-probe issue is resolved, another great way to confirm your DL devices are working properly is with the fbi (“linux framebuffer imageviewer”) utility.

sudo apt-get install fbi

Run the above to install fbi (on Ubuntu/Debian).

fbi -d /dev/fb0 -a *.jpg

And this to show a full-screen slideshow with fbi — replacing “/dev/fb0″ with one of your DisplayLink devices. You can “ls /sys/class/graphics/” to see all your framebuffer devices, and look within those directories for details on them. Of course, run the fbi utility from a directory with some jpgs (or other images) to display. pg-up/pg-down to move between photos.

You must run the fbi program from a console (fbi limitation). So hit Ctrl-Alt-F1 or something first, login from that text console, and run from there.

This wouldn’t work with older versions of udlfb or displaylink-mod (without defio support), and it makes a nice new test case. Now, short instructions for getting mplayer working for fbdev video would be welcome …

2 thoughts on “fbi – linux framebuffer imageviewer”

  1. I am just trying out my new DL-160 device, with defio on Debian, Linux version 2.6.31-1. I do get gibberish on loading the module, but running “fbset -i” refreshes the screen to a blank one. I am successfully running X with fbdev, and various operations, especially scrolling, cause random horizontal lines to appear on the screen (these lines seem to correspond to the old content which is somehow not getting scrolled). This too gets cleared each time I run fbset -i. (It seems to do a screen refresh.)

  2. Hi Srinivas,

    Thanks for the report. I was seeing similar problems, and it appeared to be from multiple processes (either at kernel or user mode) touching the framebuffer simultaneously. Udlfb itself touched pages, causing some areas of the screen to not update. The defio branch has a fix for that issue. The other culprit may be the console – fbcon. If it is rendering to the screen at the same time, it might cause these issues. Take a look at those two things, and please report back if the issue is still happening.

    Thanks!
    Bernie

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