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snippets:greenwindow

What?

Collecting pieces around something I call “green window project”.

Moving into a very small flat in Tokyo, with no good view outside? Ideas of using computer screens to replace windows are coming up. Most interesting is to collect content: waterfalls, nature and so on, free content. Kickstarter projects are also around: https://www.kickstarter.com/projects/atmoph/atmoph-window-your-room-can-be-anywhere .

TV or monitor?

Should a monitor or TV be used?

  • 24“ and smaller, TV and monitor are equally expensive, but only TVs are available at bigger sizes
  • Are 1920×1080 pixel enough? Using 4k will bring in the issue of having to supply the resolution.
  • 4k nonitors are worse with contrast apparently
  • monitors also have USB-hub usually
  • C'T 11/2015 has optimized settings for TV: Samsung UE40HU6900S

TV settings

Many settings of a TV are not appropriate here. Example: Samsung UE40HU6900S

  • Βy default, the picture is cropped on all 4 edges. This can be fixed in the menu: picture/picture format/picture format: adapt
  • picture is optimized for TV by default, not monitor. To tune (german):
    • Einstellungen / Bild / Hintergrundbel.: 6, Kontrast 90, Helligkeit 45, Schärfe 0
    • Bildformat: Bildanpassung
    • Erweiterte Einstellungen: Optimalkontrast: aus, Nur RGB-Modus: aus
    • Bildoptionen: Farbton: Warm2, Digital aufbereiten: aus, MPEG-Rauschfilter: aus, HDMI-Schwarzpegel: gering, Motion Plus: aus

resolution

The bigger the better, but..

  • higher resolutions are also harder to supply with compute devices
  • higher resolution content for the “greenwindow” is rarer
  • intel Haswell desktop cpus for desktops can supply UHD-resolution 3840×2160 with 6hz via DisplayPort (mobile cpus support this only since Broadwell - but not Celeron/Pentium, here only 1920×1200 and 2560×1600 are allowed via DisplayPort)
  • maybe the TV/monitor can independently display the content when i.e. supplied via USB/nfs- or samba share.

compute

Bringing audio, video or pictures to the TV/monitor

  • TV/monitor The device itself is able to show a picture show or the desired videos.
    • one can supply media on a usb stick or usb harddisk.
    • A DLNA server on a linuxbox can export directories with media files, the TV can then display it. Works also for 4k material - but a busy wlan does not provide the required bandwidth. This is what I use mostly. Simple. “dnf install -y minidlna; vi /etc/minidlna.conf; systemctl start minidlna”
  • arm raspberry pie 2 is reported to to 4k with 15fps according to this, additional hardware used? The kickstart project uses an intel core cpu.
  • x86 I have an unused thinkpad around. It has displayport output, but no usable audio. Do USB graphiccards for 2560x and higher resolutions exist?
  • HDMI1.4 can do 4k resolutions with 30hz, 1920×1080 with 60Hz
  • HDMI2.0
    • can do 4k resolutions with 60hz (some monitors with HDMI2.0 just entered the market)
    • only a few highend graphiccards support output to HDMI2.0
  • Displayport1.1 does 4k resolutions with 30hz, the thinkpad x230 has an Intel(R) HD Graphics 4000 which only supports Displayport1.1a
  • Displayport1.2 does 4k resolutions with 60hz, most 4k monitors are capable of this mode
  • Displayport1.3 and Embedded Displayport 1.4a support 5k and 8k resolutions, but as of now no hardware supports it
  • DVI can only transport 2560×1440 with 60Hz to the monitor

content

The content should be free.

  • pictures:
    • A script, searching google image search for “nature” and displaying the results?
    • Script displaying random pictures from the harddisk, that have high resolution?
    • script displaying flicker pictures, i.e. from Hidehiko Sakashita / https://www.flickr.com/photos/hidesax/
  • video: youtube, playing waterfalls or tree scenes? Is there better free content?
  • audio: a media player
  • weather: seeing videolike what the weather is

bringing content into the TV

Many computers like the thinkpad x230 here still have displayport 1.1a or other output which does not provide 4k resolution.

  • Miracast is the right protocol for mirroring a device to the TV. Yet, Linux as source is almost unusable. Was only reported to have worked on one wlan model.
  • minidlna can offer video files to be played. Yet, still no live streaming of a computer screen. The DLNA protocol might specify also streaming types.

notes

  • xrandr: I use xrandr directly to configure the screen connected to Linux: `xrandr –output HDMI1 –auto –below LVDS1`
  • pulseaudio: The snd_hda_codec_hdmi module provides here the audio output. After turning the TV off, the audio output often appears as “unplugged”, even the TV is turned on again. Hacky workaround: `xrandr -s 0; xrandr –output HDMI1 –auto –below LVDS1`
snippets/greenwindow.txt · Last modified: 2024/03/03 09:06 by chris