• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 98 subscribers
  • Views 535 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Anyone with experience with SDVENC/Composite Output - e.g. panning?

Karl Krach
Intellectual 320 points

Hello,

since there is no source for the HDMI kernel module and we have to use a self-compile kernel, we use the SD Video Encoder (as documented here). To get it working, I configure it this way:

echo 0 > /sys/devices/platform/vpss/graphics0/enabled
echo "1:sdvenc" > /sys/devices/platform/vpss/graphics0/nodes
echo "720,480" > /sys/class/graphics/fb0/virtual_size
echo 1 > /sys/devices/platform/vpss/graphics0/enabled

It shows an output - it fills the screen, but I have the following problems:

  1. 10px or 15px on all sides are cropped
  2. Picture is flickering

So I tried the following - but without any effect:

echo "10,10" > /sys/class/graphics/fb0/pan

Do you have any hints for me?

Best regards,

Charly

 

PS: At the end my configuration looks like this:

Accessing /sys/class/graphics/fb0 (29:0):
   Size:       720,480
   Resolution: 32 pixel
   Rotate:     0
Accessing '/sys/devices/platform/vpss/graphics0'
    /sys/devices/platform/vpss/graphics0/enabled -> 0
    /sys/devices/platform/vpss/graphics0/nodes -> 1:sdvenc
Accessing SD VENC:
   /sys/devices/platform/vpss/sdvenc/clksrc -> dclk
   /sys/devices/platform/vpss/sdvenc/enabled -> 1
   /sys/devices/platform/vpss/sdvenc/mode -> ntsc
   /sys/devices/platform/vpss/sdvenc/output -> component,yuv422spuv
   /sys/devices/platform/vpss/sdvenc/timing -> 0,720/0/0/0,480/0/0/0/0/0/0,0/0

 

  • 0
    TI__Mastermind 43875 points

    Karl,

    All TVs do what is called 'over scan', which effectively clips the outer 5% - 10%  of the image. This is a throwback to the old analog TV days where the picture size could not be easily controlled accurately in the TV so they made the image larger than the tube so as not to 'waste' any display area. TV manufacturers still do this since most source content is still designed to accommodate this over scanning. It is even done for HD content on some TVs !!!

    If you do not want your image to be clipped by the TV then you need to reduce your active area yourself.

    Now, the difficulty is that every TV manufacturer over scans by a different amount. Many TVs have an option to disable over scan, but not all do.

    BR,

    Steve

  • 0 in reply to Steve Clynes
    Intellectual 320 points

    Steve,

    thanks for this information. Do you know if this "/sys/class/graphics/fb0/pan" is working? This would be great, because it's much easier to set panning of "10,10" and reduce the widget width&height by 20px.

    Charly