Add a standalone FT8 decoder, for testing.

CMakeLists.txt

@@ -452,6 +452,8 @@ set (wsjt_FSRCS
   lib/ft8/ft8b.f90
   lib/ft8/ft8code.f90
   lib/ft8/ft8_downsample.f90
+  lib/ft8.f90
+  lib/ft8dec.f90
   lib/ft8/ft8sim.f90
   lib/gen4.f90
   lib/gen65.f90
@@ -1245,6 +1247,9 @@ target_link_libraries (jt65 wsjt_fort wsjt_cxx)
 add_executable (ft8code lib/ft8/ft8code.f90 wsjtx.rc)
 target_link_libraries (ft8code wsjt_fort wsjt_cxx)
 
+add_executable (ft8 lib/ft8.f90 wsjtx.rc)
+target_link_libraries (ft8 wsjt_fort wsjt_cxx)
+
 add_executable (ft8sim lib/ft8/ft8sim.f90 wsjtx.rc)
 target_link_libraries (ft8sim wsjt_fort wsjt_cxx)
 

lib/ft8.f90

@@ -0,0 +1,49 @@
+program ft8
+
+  integer*2 iwave(15*12000)
+  logical lft8apon,lapcqonly,nagain,newdat
+  character*12 mycall12,hiscall12
+  character*6 hisgrid6
+  character arg*8,infile*80
+  integer ihdr(11)
+
+  nargs=iargc()
+  if(nargs.lt.3) then
+     print*,'Usage:   ft8 nfa  nfb ndepth    infile'
+     print*,'Example: ft8 200 4000   3  181201_180315.wav'
+     go to 999
+  endif
+  call getarg(1,arg)
+  read(arg,*) nfa
+  call getarg(2,arg)
+  read(arg,*) nfb
+  call getarg(3,arg)
+  read(arg,*) ndepth
+  nfiles=nargs-3
+
+  nQSOProgress=0
+  nfqso=1500
+  nftx=0
+  newdat=.true.
+  nutc=0
+  ncontest=0
+  nagain=.false.
+  lft8apon=.false.
+  lapcqonly=.false.
+  napwid=75
+  mycall12='K1ABC'
+  hiscall12='W9XYZ'
+  hisgrid6='EN37wb'
+
+  do ifile=1,nfiles
+     call getarg(3+ifile,infile)
+     open(10,file=infile,status='old',access='stream')
+     read(10) ihdr,iwave
+     close(10)
+
+     call ft8dec(iwave,nQSOProgress,nfqso,nftx,newdat,            &
+          nutc,nfa,nfb,ndepth,ncontest,nagain,lft8apon,lapcqonly, &
+          napwid,mycall12,hiscall12,hisgrid6)
+  enddo
+
+999 end program ft8

lib/ft8dec.f90

@@ -0,0 +1,111 @@
+subroutine ft8dec(iwave,nQSOProgress,nfqso,nftx,newdat,        &
+       nutc,nfa,nfb,ndepth,ncontest,nagain,lft8apon,lapcqonly, &
+       napwid,mycall12,hiscall12,hisgrid6)
+!    use wavhdr
+    use timer_module, only: timer
+    include 'ft8/ft8_params.f90'
+!    type(hdr) h
+
+    parameter (MAXCAND=300)
+    real s(NH1,NHSYM)
+    real sbase(NH1)
+    real candidate(3,MAXCAND)
+    real dd(15*12000)
+    logical, intent(in) :: lft8apon,lapcqonly,nagain
+    logical newdat,lsubtract,ldupe
+    character*12 mycall12,hiscall12,mycall12_0
+    character*6 hisgrid6
+    integer*2 iwave(15*12000)
+    integer apsym2(58)
+    character datetime*13,msg37*37
+!   character message*22
+    character*37 allmessages(100)
+    integer allsnrs(100)
+    data mycall12_0/'dummy'/
+    save s,dd,mycall12_0
+
+    if(mycall12.ne.mycall12_0) then
+       mycall12_0=mycall12
+    endif
+
+    write(datetime,1001) nutc        !### TEMPORARY ###
+1001 format("000000_",i6.6)
+
+    call ft8apset(mycall12,hiscall12,apsym2)
+    dd=iwave
+    ndecodes=0
+    allmessages='                                     '
+    allsnrs=0
+    ifa=nfa
+    ifb=nfb
+    if(nagain) then
+       ifa=nfqso-10
+       ifb=nfqso+10
+    endif
+
+! For now:
+! ndepth=1: no subtraction, 1 pass, belief propagation only
+! ndepth=2: subtraction, 3 passes, belief propagation only
+! ndepth=3: subtraction, 3 passes, bp+osd
+    if(ndepth.eq.1) npass=1
+    if(ndepth.ge.2) npass=3
+    do ipass=1,npass
+      newdat=.true.  ! Is this a problem? I hijacked newdat.
+      syncmin=1.5
+      if(ipass.eq.1) then
+        lsubtract=.true.
+        if(ndepth.eq.1) lsubtract=.false.
+      elseif(ipass.eq.2) then
+        n2=ndecodes
+        if(ndecodes.eq.0) cycle
+        lsubtract=.true.
+      elseif(ipass.eq.3) then
+        if((ndecodes-n2).eq.0) cycle
+        lsubtract=.false. 
+      endif 
+      call timer('sync8   ',0)
+      maxc=MAXCAND
+      call sync8(dd,ifa,ifb,syncmin,nfqso,maxc,s,candidate,   &
+           ncand,sbase)
+      call timer('sync8   ',1)
+      do icand=1,ncand
+        sync=candidate(3,icand)
+        f1=candidate(1,icand)
+        xdt=candidate(2,icand)
+        xbase=10.0**(0.1*(sbase(nint(f1/3.125))-40.0))
+        nsnr0=min(99,nint(10.0*log10(sync) - 25.5))    !### empirical ###
+        call timer('ft8b    ',0)
+        call ft8b(dd,newdat,nQSOProgress,nfqso,nftx,ndepth,lft8apon,      &
+             lapcqonly,napwid,lsubtract,nagain,ncontest,iaptype,mycall12,   &
+             hiscall12,sync,f1,xdt,xbase,apsym2,nharderrors,dmin,           &
+             nbadcrc,iappass,iera,msg37,xsnr)
+        call timer('ft8b    ',1)
+        nsnr=nint(xsnr) 
+        xdt=xdt-0.5
+        hd=nharderrors+dmin
+        if(nbadcrc.eq.0) then
+           ldupe=.false.
+           do id=1,ndecodes
+              if(msg37.eq.allmessages(id).and.nsnr.le.allsnrs(id)) ldupe=.true.
+           enddo
+           if(.not.ldupe) then
+              ndecodes=ndecodes+1
+              allmessages(ndecodes)=msg37
+              allsnrs(ndecodes)=nsnr
+           endif
+!           write(81,1004) nutc,ncand,icand,ipass,iaptype,iappass,        &
+!                nharderrors,dmin,hd,min(sync,999.0),nint(xsnr),          &
+!                xdt,nint(f1),msg37
+!1004          format(i6.6,2i4,3i2,i3,3f6.1,i4,f6.2,i5,2x,a37)
+!           flush(81)
+           if(.not.ldupe) then
+              qual=1.0-(nharderrors+dmin)/60.0 ! scale qual to [0.0,1.0]
+              write(*,1010) min(sync,999.0),nsnr,xdt,nint(f1),   &
+                   iaptype,qual,msg37
+1010          format(f5.1,i4,f5.2,i5,i3,f5.1,1x,a37)
+           endif
+        endif
+      enddo
+  enddo
+  return
+end subroutine ft8dec