WSJT-X/libm65/extract.F

110 lines
3.1 KiB
Fortran

subroutine extract(s3,nadd,ncount,nhist,decoded,ltext)
real s3(64,63)
real tmp(4032)
character decoded*22
integer era(51),dat4(12),indx(64)
integer mrsym(63),mr2sym(63),mrprob(63),mr2prob(63)
logical first,ltext
data first/.true./,nsec1/0/
save
nfail=0
1 continue
! call timer('demod64a',0)
call demod64a(s3,nadd,mrsym,mrprob,mr2sym,mr2prob,ntest,nlow)
! call timer('demod64a',1)
if(ntest.lt.50 .or. nlow.gt.20) then
ncount=-999 !Flag bad data
go to 900
endif
call chkhist(mrsym,nhist,ipk)
if(nhist.ge.20) then
nfail=nfail+1
call pctile(s3,tmp,4032,50,base) ! ### or, use ave from demod64a
do j=1,63
s3(ipk,j)=base
enddo
if(nfail.gt.30) then
decoded=' '
ncount=-1
go to 900
endif
go to 1
endif
call graycode(mrsym,63,-1)
call interleave63(mrsym,-1)
call interleave63(mrprob,-1)
ndec=1
nemax=30 !Was 200 (30)
maxe=8
xlambda=13.0 !Was 12
if(ndec.eq.1) then
call graycode(mr2sym,63,-1)
call interleave63(mr2sym,-1)
call interleave63(mr2prob,-1)
nsec1=nsec1+1
write(22,rec=1) nsec1,xlambda,maxe,200,
+ mrsym,mrprob,mr2sym,mr2prob
call flush(22)
! call timer('kvasd ',0)
#ifdef UNIX
iret=system('./kvasd -q > dev_null')
#else
iret=system('kvasd -q > dev_null')
#endif
! call timer('kvasd ',1)
if(iret.ne.0) then
if(first) write(*,1000) iret
1000 format('Error in KV decoder, or no KV decoder present.'/
+ 'Return code:',i8,'. Will use BM algorithm.')
ndec=0
first=.false.
go to 20
endif
read(22,rec=2) nsec2,ncount,dat4
j=nsec2 !Silence compiler warning
decoded=' '
ltext=.false.
if(ncount.ge.0) then
call unpackmsg(dat4,decoded) !Unpack the user message
if(iand(dat4(10),8).ne.0) ltext=.true.
do i=2,12
if(dat4(i).ne.dat4(1)) go to 20
enddo
write(13,*) 'Bad decode?',nhist,nfail,ipk,
+ ' ',dat4,decoded
ncount=-1 !Suppress supposedly bogus decodes
decoded=' '
endif
endif
20 if(ndec.eq.0) then
call indexx(63,mrprob,indx)
do i=1,nemax
j=indx(i)
if(mrprob(j).gt.120) then
ne2=i-1
go to 2
endif
era(i)=j-1
enddo
ne2=nemax
2 decoded=' '
do nerase=0,ne2,2
call rs_decode(mrsym,era,nerase,dat4,ncount)
if(ncount.ge.0) then
call unpackmsg(dat4,decoded)
go to 900
endif
enddo
endif
900 return
end