From 42b6ef859c9f4587d6b99e5fab2611bd08647e51 Mon Sep 17 00:00:00 2001
From: Steven Franke <s.j.franke@icloud.com>
Date: Tue, 12 Jul 2016 18:29:46 +0000
Subject: [PATCH] Remove bit re-ordering in msk144.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6908 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
---
 lib/detectmsk144.f90 | 8 ++------
 lib/genmsk144.f90    | 9 ++-------
 2 files changed, 4 insertions(+), 13 deletions(-)

diff --git a/lib/detectmsk144.f90 b/lib/detectmsk144.f90
index 5705439b6..062085df8 100644
--- a/lib/detectmsk144.f90
+++ b/lib/detectmsk144.f90
@@ -39,8 +39,7 @@ subroutine detectmsk144(cbig,n,pchk_file,lines,nmessages,nutc,ntol)
   real tonespec(NFFT)
   real*8 dt, df, fs, pi, twopi
   real softbits(144)
-  real*8 unscrambledsoftbits(128)
-  real lratio(128)
+  real*8 lratio(128)
   logical first
   data first/.true./
   data s8/0,1,1,1,0,0,1,0/
@@ -352,12 +351,9 @@ subroutine detectmsk144(cbig,n,pchk_file,lines,nmessages,nutc,ntol)
               lratio(49:128)=softbits(65:65+80-1)
               lratio=exp(2.0*lratio/(sigma*sigma))
   
-              unscrambledsoftbits(1:127:2)=lratio(1:64)
-              unscrambledsoftbits(2:128:2)=lratio(65:128)
-
               max_iterations=10
               max_dither=1
-              call ldpc_decode(unscrambledsoftbits, decoded, &
+              call ldpc_decode(lratio, decoded, &
                            max_iterations, niterations, max_dither, ndither)
 
               if( niterations .ge. 0.0 ) then
diff --git a/lib/genmsk144.f90 b/lib/genmsk144.f90
index fe7afb737..949621393 100644
--- a/lib/genmsk144.f90
+++ b/lib/genmsk144.f90
@@ -31,7 +31,6 @@ subroutine genmsk144(msg0,ichk,msgsent,i4tone,itype,pchk_file)
   integer*1, target:: i1Msg8BitBytes(10)  !80 bits represented in 10 bytes 
   integer*1 codeword(128)                 !Encoded bits before re-ordering
   integer*1 msgbits(80)                   !72-bit message + 8-bit hash
-  integer*1 reorderedcodeword(128)        !Odd bits first, then even
   integer*1 bitseq(144)                   !Tone #s, data and sync (values 0-1)
   integer*1 i1hash(4)
   integer*1 b7(7)
@@ -124,17 +123,13 @@ subroutine genmsk144(msg0,ichk,msgsent,i4tone,itype,pchk_file)
 
      call ldpc_encode(msgbits,codeword)
 
-! Reorder the bits.
-     reorderedcodeword(1:64)=codeword(1:127:2)
-     reorderedcodeword(65:128)=codeword(2:128:2)
-
 !Create 144-bit channel vector:
 !8-bit sync word + 48 bits + 8-bit sync word + 80 bits
      bitseq=0 
      bitseq(1:8)=s8
-     bitseq(9:56)=reorderedcodeword(1:48)
+     bitseq(9:56)=codeword(1:48)
      bitseq(57:64)=s8
-     bitseq(65:144)=reorderedcodeword(49:128)
+     bitseq(65:144)=codeword(49:128)
      bitseq=2*bitseq-1
 
      xq(1:6)=bitseq(1)*pp(7:12)   !first bit is mapped to 1st half-symbol on q