Segfault > IT > Notes > Graphics
  • vobcopy - Copy vobs from dvd to hd
  • xcdroast - Burn audio and data cd (and dvd)
  • Videos with pvr350 can be grabbed with "cat /dev/video0 > output.mpg" and can be played with "cat output.mpg > /dev/video16".
  • In order to transcode from 23.97 avi to 25 mpg (dvd) a video file use:
    mencoder mymovie.avi -of mpeg -mpegopts format=mpeg2:telecine -oac lavc -ovc lavc -lavcopts acodec=mp3:vcodec=mpeg2video -ofps 25 -o mymovie.mpg
  • If you want to play it directly to the tvout modify it this way:
    mencoder mymovie.avi -of mpeg -mpegopts format=mpeg2:telecine -oac copy -ovc lavc -lavcopts vcodec=mpeg2video -ofps 25 -o /dev/video16
  • Small program that sends audio output to the pvr350: pvr350player
  • After emerging nvidia-drivers run:
    eselect opengl set nvidia
    Additionally merge "media-video/nvidia-settings".
  • gifsicle command line:
    gifsicle -D 2 -l -d 15 -t '#FFFFFF' arrow1.gif arrow2.gif arrow3.gif > arrowanim.gif
    -t '#FFFFFF' tells the program to handle the color white as transparent.
    -D 2 tells to use the background when the transparent part of the image is drawn.
    -l tells to loop, and as there is no number specified, it loops forever.
    -d 15 tells to wait 15 hundreds of seconds between the different frames.
  • Programs used to setup the modeline in linux:
    • xvidtune: try out different settings.
    • read-edid: tries to read the EDID informations in the monitor itself.
    • amlc
  • Use xvidcap as Desktop-recorder / screen capture utility.
  • Use 3ddesk as a fake 3d desktop switch utility.
  • Use avimerge to merge multiple avi files into a single one (contained in the transcode package).
  • Motiontrack to find differencies (e.g. if something has moved) between two pictures.
  • How to convert "ts" (transport stream) files to othe formats:
    http://www.togaware.com/linux/survivor/Converting_Transport.html
    http://gentoo-wiki.com/HOWTO_Master_a_DVD_from_DVB_transport_stream
    http://www.m740.de/wiki/Aufnahmen_schneiden_und_auf_DVD_brennen_unter_Linux
  • A nice site where to find subtitles for movies: http://www.moviesubtitles.org/
  • Use ogmrip to convert DVDs to mkv-files.
  • "feh" is a lightweight image viewer.
  • Use dvbcut to cut and remux "ts" files to "mpg".
  • To be able to recode to x264 or just backup some protected DVDs, use 1) dvdfab decrypter or CopyToDVD (from vso-software), then FixVTS, then Nero Recode or ogmrip or whatever.
  • In order for a user (userA) to have access to the X display started by another user (userX), the user requesting access (userA) will have to set the variable XAUTHORITY to the path of the .Xauthority file of the user owning X (userX). In this case:
    userA@computer ~ $ export XAUTHORITY=/userX/.Xauthority
    The .Xauthority file is re-created each time X is started! Therefore put some kind of e.g. chmod 704 /userX/.Xauthority in your X-start file (e.g. /etc/X11/Sessions/enlightenment)
  • Use podcatcher to download podcasts. Files which are being downloaded are stored in the /tmp/ directory.
  • About Compiz-Fusion:
    • Set up graphics drivers: http://en.gentoo-wiki.com/wiki/Graphics_drivers
    • Radeon ATI graphics drivers: http://de.gentoo-wiki.com/wiki/Radeon
    • Set up Compiz: http://en.gentoo-wiki.com/wiki/Compiz-Fusion
    • When using Gnome, add to "System > Preferences > Startup Applications" an entry for "/usr/bin/compiz-manager". Other ways of setting it up with Gnome didn't work for me. 
  • "cvt" can be used to generate the modelines of xorg.conf.
  • Samtron 94v specs:
    Display area: 372.32 (H) x 301.56 (V)
    Pixel pitch: 0.294mm (H) x 0.294mm (V)
    Type: a-si TFT active matrix
    Horizontal synchronization: 31 ~ 81 kHz
    Vertical synchronization: 56 ~ 75 Hz
    Colors: 16,194,277
    Optimum resolution: 1280 x 1024@60 Hz
    Maximum resolution: 1280 x 1024@75 Hz
    Input signal: RGB Analog , 0.7Vp-p Positive at 75 ohms, Separate H/V sync, Composite sync, SOG, TTL level positive or negative.
    Maximum pixel clock: 135 MHz
    Power: AC 100 ~ 240 VAC(+/- 10%), 60/50 Hz ± 3Hz
    Signal cable: 15pin-to-15pin D-sub cable, Detachable
    Power consumption: Less than 38W
    Dimensions and weight: 428.0 X 204.0 X 433.0 mm / 16.9 x 8.0 x 17.0 inch (With Basic Stand) / 6.25kg
    Preset timings - optimum:
       + VESA, 1280 x 1024
       + Horiz freq: 63.981
       + Vert freq: 60.020
       + Pixel clock: 108.00
       + Sync polarity H/V: +/+
    Preset timings - maximum:
       + VESA, 1280 x 1024
       + Horiz freq: 79.976
      + Vert freq: 75.025
      + Pixel clock: 135.00
      + Sync polarity H/V: +/+
  • Additional truetype fonts can be put under "/usr/share/fonts". Afterwards X needs to be restarted.
  • To generate animated gifs:
    • Create somehow the single frames in any format, e.g. png.
    • Modify their size (using Imagemagick):
      mogrify -resize 130 -format gif frame_*.png
    • Perhaps change a color to transparent (using Imagemagick):
      for f in frame*
      do
       echo Processing $f and creating transparent-$f
       convert -transparent "rgb(255,255,255)" -fuzz "25%" -format gif $f transparent-$f.gif
      done
    • Create the animated gif (using gifsicle):
      gifsicle --delay=5 --loopcount=0 --colors 16 --careful -O3 --disposal background transparent-frame_000* > myanim.gif
    • After having created the animated GIF, you can change the properties of some of the frames.
      E.g. here...
      gifsicle -b mylogo.gif -d900 "#0"
      ...I set the delay of the first frame of the animation to 9 seconds.
  • FFMPEG commands:
    • Create a screencast of the desktop 0.0:
      ffmpeg -f x11grab -r 25 -s wxga -i :0.0 /tmp/outputFile.mpg
    • Create a video out of single images
      ffmpeg -f image2 -i img%d.jpg /tmp/a.mpg
  • Webcam reminders:
    • Use the programs "motion" or "zoneminder" to use the webcam to monitor the house/flat/area.
    • Install the package "v4l-utils" for the extra v4l2 utilities.
    • Run the command "v4l2-ctl -d /dev/video --list-formats" to show the formats supported by the webcam.
    • Run the command "v4l2-ctl -d /dev/video --list-formats-ext" to show the formats and resolutions supported by the webcam.
    • Run the command "v4l2-ctl -d /dev/video --set-fmt-video=width=,height=,pixelformat=" to set the resolution and streaming format of the webcam. So, e.g. "v4l2-ctl -d /dev/video1 --set-fmt-video=width=1280,height=720,pixelformat=MJPG" to set the resolution to 720p and a JPEG stream.
    • Test the camera with e.g. "mplayer -v tv:// -tv device=/dev/video1:driver=v4l2:width=1920:height=1080:fps=30:outfmt=mjpg"
  • List the available framebuffer resolutions:
    hwinfo --framebuffer
  • To set a different font in Eterm:
    Set it e.g. like this: Eterm -F -misc-fixed-medium-r-normal--14-*-*-*-*-*-iso8859-1
    Find out how the cryptic string has to/can be set with the utility "xfontsel".
    Perhaps get rid of the menu at the top with the parameter "--buttonbar 0".
  • To enable the key-combination shift-arrow up/shift-arrow down to scrollback 1/single lines, create in your home directory a file called ".Xresources" and add to it the following line:
    ===================
    *VT100.Translations: #override Shift Up: scroll-back(1) \nShift Down: scroll-forw(1)
    ===================
    Enable the changes by running the command "xrdb -m ~/.Xresources"
  • If your Adobe flash videos look blue when using a nVidia GPU, add the following to the file "/etc/adobe/mms.cfg" after having compiled adobe-flash with vdpau support:
    ===================
    EnableLinuxHWVideoDecode=1
    OverrideGPUValidation=true
    ===================