Monday, September 29, 2014

PXL 2000 Decoder

Special thanks to Mike Leslie for helping with the project.  Mike suggested using the first derivative of the signal, rather than direct AM signal (this smooths out the DC offset).  :-)

Previous I posted some old notes about the PXL 2000 video signal here.   Writing a decoder seemed like an interesting project, and it came together a bit faster than I expected.  Now it's fully functional, though could use a few tweaks.

This decoder can convert a PXL 2000 video signal from either a wav file or line-in to digital video.   In theory, you may be able to recover signal from tapes that no longer play in a PXL 2000 camcorder (with proper boost/compression).

Screenshot:



Features:

  • can decode from line-in or wav file
  • shows preview of decoded video
  • brightness/contrast control
  • speed control
  • sync controls
  • converts video signal to png frames
  • resamples audio to normal speed
  • creates a sample avconv script (with calculated fps) that will create a video file
  • saves time code of each frame
  • offers both GUI and command line modes

Requirements:

  • Java JDK 6+ to compile, and 
  • You'll need something like avconv or ffmpeg to merge the decoded png's and audio to a video format. 
  • If you use a wav file, the decoder is currently tuned for  stereo 16-bit audio sampled at 192khtz.


Source code and documentation is at:

    https://github.com/sevkeifert/pxl-2000-decoder


4 comments:

T.Ishimuni said...

Magical. The finest retro-tech.
1987 would be proud ;-)

Unknown said...

could you hook a digital audio recorder directly to a pxl-2000?

Kevin said...

If you record from the rca video output it would be ntsc signal.

OTOH, if you wanted to record the native pxl signal to an external recorder, I think it might need to pull the signal off the play/record head. There used to to be cassette adapters but I'm not sure they'll work work with the high frequencies used by the pxl.

polycube said...

OMG. I am so happy to live in a future where people do this... and I was looking for this exact tool for a couple of PXL cassettes I discovered in my stuff. So. Ok. Here goes.