[mpeg2] Re: Jumpy Video

[Torsten Howard <torsten@inetw.net>]

One more question.  This is a long time in coming.
Setting PAL/NTSC dynamically.

How do I modify kernel parameters from user space?
I guess it would be necessary to write a /dev interface
for the kfir module?

If anyone has a pointer to a web page or book 
recommendation, I would be grateful.

Thanks,
Torsten



On Friday 17 August 2001 11:31 am, you wrote:
> Here is some info in the saa7113 by phillips:
>
> http://www.semiconductors.philips.com/acrobat/datasheets/SAA7113H_1.pdf
>
> I was quickly reviewing it, and you might want to check out:
>
> fig 15.2.7 and 15.2.8 - horizontal sync start and stop
> 15.2.9 -
>
> you might also want to start polling some of the info on page 15.2.19
> fig49, esp the HL, VL, HREF_HS..
>
> This is all from the I2C bus, you might want to grep the kfir code for some
> I2C code..   i just havent had the time to play with it.
>
> Good luck,
> Jason
>
> > > Thank
>
> you!  I was about to write and offer up my thoughts
> - the > problem looks like a vsync and hsync problem, and I was thinking
>
> > the synch signals were not being caught.
> >
> > I had no idea a TBC existed, I'll research.  Is it also possible to
> > increase the saa7113 tolerance in software?  If so, where would
> > I find it?
> >
> > Torsten
> >
> > On Friday 17 August 2001 09:41 am, you wrote:
> > > Might I sugggest acquring what is referred to as a TBC, or time base
> > > corrector with sync regeneration.  These could probably be found on
> > > ebay, or your local (high end) electronics store.
> > >
> > > This is probably due to the fact that the SAA7113 has a low tolerance
> > > for losing video sync, and the I2C interface for the driver is lacking
> > > updating the adc chip.
> > >
> > > Good luck,
> > > Jason
> > >
> > > Hi, I'm wondering if anyone may have some advice > for me.  Or even a
> > > solution!
> > >
> > > > I have jumpy video problems.  Not all the time - when
> > > > the video signal is strong and clear (recent video) I
> > > > can encode no problem.
> > > >
> > > > I have currently three (of about 30) movies that won't
> > > > record.  Two of the videos are old - 70's 8mm
> > > > transferred to videocasette.  The colors are washed
> > > > out, or not well saturated, and the image is not as
> > > > sharp as video produced with modern camcorders.
> > > >
> > > > The other movie is from the 80's - similar situation
> > > > but a better image.
> > > >
> > > > The audio has wierd problems where it goes a few
> > > > seconds, and the makes a sound like stopping a
> > > > record.  I don't know if it relates to the video.
> > > >
> > > > The video itself jumps around, holds steady for a
> > > > few seconds, then jumps again.  It really drives me
> > > > insane.
> > > >
> > > > Anyone with similar problems, or a solution?
> > > >
> > > > Thanks,
> > > > Torsten