Re: modified webcam software for visually impaired

[Eitan Isaacson <eitan monotonous org>]

Looks like your webcam is not automatically getting picked up by gstreamer.

run gstreamer-properties (in Ubuntu it's in the gnome-media package), and make sure the video default input works, or configure it appropriately.

2011/1/4 Helios <heliooos gmail com>

Hi Eitan,
I am not sure if I did all correctly but.... I installed frei0r-filter
(first I googled a little to find out what is it)  from Ubuntu
repository, but when I tried the supplied command, I got this output:

petra HP550:/home/psychopetra/Plocha$ gst-launch-0.10 autovideosrc !
ffmpegcolorspace ! frei0r-filter-bw0r !
ERROR: Could not load classifier cascade
/usr/share/opencv/haarcascades/haarcascade_frontalface_alt2.xml
ERROR: Could not load classifier cascade
/usr/share/opencv/haarcascades/haarcascade_frontalface_alt2.xml
VAROVÁNÍ: chybná roura: propojení bez elementu spotřebiče
petra HP550:/home/psychopetra/Plocha$

It is in Czech - the last but one row means something like "Warning:
incorrect pipe: connection without device element

I tried to install python-opencv, but I again got this:

E: yaml-mode: podproces instalovaný post-installation skript vrátil
chybový status 1
(subprocess installed post-installation skrict returned error status 1)

Helios

Vinux 3.0 (Ubuntu Lucid, Kernel 2.6.32-27-generic), Gnome 2.30.2,
HP550 laptop: Intel Celeron, 1GB ram, Intel graphics

2011/1/4 Eitan Isaacson <eitan monotonous org>:

> On Sat, Jan 1, 2011 at 1:56 PM, Helios <heliooos gmail com> wrote:
>>
>> Hi,
>> we are just testing a standard webcam to be used as a digital
>> magnifier for visually impaired users. Such gadget could be very
>> useful, as many low vision users need such device, but those
>> commercially available are Windows only and mostly very expensive.
>> We tested common Genius webcam with manual focus feature using Cheese,
>> however, there are no features needed for this kind of users (supplied
>> by my visually impaired sister):
>> - inverse color mode
>
>
> gst-launch-0.10 autovideosrc ! ffmpegcolorspace ! frei0r-filter-bw0r !
> frei0r-filter-invert0r ! ffmpegcolorspace ! autovideosink
>>
>> - color profiles (eg. yellow text on blue background - simple runs in
>> BW mode only and replaces black with yellow and white with blue)
>
>
> gst-launch-0.10 autovideosrc ! ffmpegcolorspace ! frei0r-filter-contrast0r
> contrast=0.7 ! frei0r-filter-bw0r ! frei0r-filter-invert0r !
> frei0r-filter-levels white-output=0.06 black-output=0.27 channel=2 !
> ffmpegcolorspace ! autovideosink
>>
>> - guiding lines (can provide some screenshots)
>
> There should be an easy way of doing that.
>
>>
>> - and some others
>>
>
> The options are limitless! And it would be fun to create a simple UI for all
> that.

--
S pozdravem

Helios