AVANT 0.94 - Decoding pay TV
============================
  Last Updated: 19-11-98
============================

1.0 Overview
2.0 Use
    2.1 Is it legal ?
    2.2 What does AVANT need ?
    2.3 How I can start AVANT ?
    3.4 What's about the performance ?
    2.5 Where can I get AVANT ?
    2.6 How does AVANT work ?
    2.7 History
3.0 Other software Pay-TV hacks
4.0 Credits

1.0 OVERVIEW
============

AVANT is the Anti Videocrypt Anti Nagravision Tool. AVANT can decrypt
Videocrypt (VCI, VCII) and Nagravision/Syster crypted TV-channels on
Windows 95 computers with a TV-Card. Sadly AVANT isn't very fast.
It works only black and white because the capturing of encrypted signal
disturb the colour information.

2.0 Use
=======

2.1 Is it legal ?
---------------
I don't know much about the legality. But I ask you: does this sound
legal? You are on the better side, if you don't use AVANT...
But AVANT don't require secret information (keys...) to decode.
 *  This software is only provided for scientific demonstration
 *  purposes as an example of an interesting signal processing
 *  algorithm. The authors reject any responsibility for pay-TV
 *  piracy abuses of this software.

2.2 What does AVANT need ?
--------------------------
You should have a videocapturecard and drivers for WIN95 (or NT). My
capturecard is a Happauge Win/TV (Bt848-Chip). I work also on a
MiroPCTV. Other cards should work, but they must support the preview
mode. If they only support the overlay mode, AVANT don't work, because
this mode is a hardware function that displays the contents of the
capture buffer on the monitor directly (DMA).
AVANT supports only 15/16Bit Pal and 24Bit Pal and your capture
screensize should be 768x576 (768x567 was wrong), 1024x768, 704x576,
352x288. Other resolution need the userresolution in the
decodeoptions (you have to fill in this by yourself).


AVANT needs some dll's. You can get them were you AVANT can get (2.5).

2.3 How I can start AVANT ?
---------------------------
First make sure that your TV-card supports the preview mode (Options->
preview). If only overlay works, AVANT cant decode.
Now you choose your input source (Options->Source...). Only Pal
channels are working. In AVANT you can select the tuner but you can't
select the channels.
Then choose in Options->Format... Full Resolution and 15, 16 or
24 bit RGB.
Choose the Options->Decryptsettings... Menu. Here you can select
Videocrypt or Nagravision decode. If you use 16 Bit Pal make sure,
that you selected R=5 G=6 B=5. (15 Bit R=5 G=5 B=5)
If your capturecard supports none of the AVANT resolutions,  write
your own resolution in the userresolution field.

 description of the options:
   VC:
     -half resolution: use only every second pixel, is faster
     -correct edge   : select, if you want decode
     -mark edge, mark brake, show deadzone:
                       select, if you want to study the algorithm
     -removed pixel columns:
                     : the algorithm needs to know, where the picture
                       begins, the value isn't for every TV card the
                       same. You have to find out the best values.
     -odd, even, all : odd and even is faster

   NAGRA / SYSTER:
     -odd, even, all : odd and even is faster
     -compare steps  : the size of the steps, higher values are faster
     -deepness       : how many lines are compared, lower is faster
     -ignore black liens:
                     : if selected all black lines aren't used (for
			movies)
     -limit of black lines
                     : low values are darker

You shold use Full Resolution (768x568). Otherwise there's a problem with
the Bt848 Chip. It adds lines together (from every frame). This means,
that some information of the picture are lost. This is not a bug, this
is a feature (better quality for normal, not encoded pictures).

3.4 What's about the performance ?
----------------------------------
performance 768*576, 24bit (since 0.92):

VC
                                  Cyrix 133       Celeron 400 MHz
full                        :      0.12 fps           0.6 fps
half resolution             :      0.21 fps           1.0 fps
half line                   :      0.23 fps           1.1 fps
half resolution, half line  :      0.33 fps           1.6 fps

Nagra
                                  Cyrix 133       Celeron 400 MHz
full                        :       0.57 fps          2   fps
half line                   :       1    fps          2.8 fps

2.5 Where can I get AVANT ?
---------------------------
From my Homepage:
http://members.xoom.com/raez/
or from SALP, the best place for TV-Card based hacks:
http://eurosat.com/salp/


2.6 How does AVANT work ?
-------------------------
The C sourcecode of AVANT is free. Load it down and make your faster AVANT!

2.7 History
-----------
AVANT 0.9  : basic version (worked only on Hauppauge?)
AVANT 0.91 : added support for 15/16Bit modes (worked only on Hauppauge?)
AVANT 0.92 : added resolution 768x567 and 384x288 (Miro PcTV)
                 thanks Peter Kooiman for the fix for the Miro PcTV
AVANT 0.93 : added new resolutions : 768x576 (768x567 was wrong),
                 1024x768, 704x576, 352x288
             it is now possible, to select a user resolution (decodeoptions)
                 limit of the userresolution: 1024 x 768
             the options are now in the registry stored:
                 HKEY_CURRENT_USER\Software\RAEZ\AVANT\Options
AVANT 0.94 : removed some compiler-warnigs (also the version of RedRat
                 gave me about 40 warnings) now I have only 19 warnings...


3.0 Other software Pay-TV hacks
===============================
For Nagravision, there are some good  real-time hacks available. There is a hack
on linux systems. Also AVT (came from AVANT) is a betterone than AVANT.

The best place for TV-Card based hacks is http://freetv.notrix.de/. Great Page.

4.0 Credits
===========
The VC algorithm is from Markus Kuhn. Thanks to him.
His (interesting) site: http://www.cl.cam.ac.uk/~mgk25/

Peter Kooiman, ClrScr for new resolutions

RedRat for changes to compile with VC++ 5.0 (marked with 19980802RedRat)
