I think the phase correction in the fix_packet function is not correct. I was wondering why your implementation gives much poorer quality images compared to the LRPT decoder from Robonuka. I am implementing my own Meteor M2 decoder, and I researched a lot how it works and what could be the problem. There is no write access to your repository, so here is what I've changed in your code, it gives much better images now.
var j:integer;
d:pshortinta;
b:shortint;
begin
d:=data;
case shift of
4:for j:=0 to len div 2-1 do begin
b:=d[j*2+0];
d[j*2+0]:= -d[j*2+1];
d[j*2+1]:= -b;
end;
5:for j:=0 to len div 2-1 do begin
d[j*2+0]:=-d[j*2+0];
end;
6:for j:=0 to len div 2-1 do begin
b:=d[j*2+0];
d[j*2+0]:= d[j*2+1];
d[j*2+1]:= b;
end;
7:for j:=0 to len div 2-1 do begin
d[j*2+1]:=-d[j*2+1];
end;
end;
end;```
I think the phase correction in the fix_packet function is not correct. I was wondering why your implementation gives much poorer quality images compared to the LRPT decoder from Robonuka. I am implementing my own Meteor M2 decoder, and I researched a lot how it works and what could be the problem. There is no write access to your repository, so here is what I've changed in your code, it gives much better images now.