#!/bin/bash
  
  # Copyright 2012  Johns Hopkins University (Author: Daniel Povey)
  #                 Korbinian Riedhammer
  
  # Decoding script that does fMLLR.  This can be on top of delta+delta-delta, or
  # LDA+MLLT features.
  
  # There are 3 models involved potentially in this script,
  # and for a standard, speaker-independent system they will all be the same.
  # The "alignment model" is for the 1st-pass decoding and to get the 
  # Gaussian-level alignments for the "adaptation model" the first time we
  # do fMLLR.  The "adaptation model" is used to estimate fMLLR transforms
  # and to generate state-level lattices.  The lattices are then rescored
  # with the "final model".
  #
  # The following table explains where we get these 3 models from.
  # Note: $srcdir is one level up from the decoding directory.
  #
  #   Model              Default source:                 
  #
  #  "alignment model"   $srcdir/final.alimdl              --alignment-model <model>
  #                     (or $srcdir/final.mdl if alimdl absent)
  #  "adaptation model"  $srcdir/final.mdl                 --adapt-model <model>
  #  "final model"       $srcdir/final.mdl                 --final-model <model>
  
  
  # Begin configuration section
  alignment_model=
  adapt_model=
  final_model=
  transform_dir=
  stage=0
  acwt=0.083333 # Acoustic weight used in getting fMLLR transforms, and also in 
                # lattice generation.
  max_active=7000
  beam=13.0
  lattice_beam=6.0
  nj=4
  silence_weight=0.01
  cmd=run.pl
  si_dir=
  fmllr_update_type=full
  # End configuration section
  
  echo "$0 $@"  # Print the command line for logging
  
  [ -f ./path.sh ] && . ./path.sh; # source the path.
  . parse_options.sh || exit 1;
  
  if [ $# != 4 ]; then
     echo "Usage: steps/tandem/mk_aslf_lda_mllt.sh [options] <graph-dir> <data1-dir> <data2-dir> <decode-dir>"
     echo " e.g.: steps/tandem/mk_aslf_lda_mllt.sh exp/tri2b/graph {mfcc,bottleneck}/data/test_dev93 exp/tri2b/decode_dev93"
     echo "main options (for others, see top of script file)"
     echo "  --config <config-file>                   # config containing options"
     echo "  --nj <nj>                                # number of parallel jobs"
     echo "  --cmd <cmd>                              # Command to run in parallel with"
     echo "  --adapt-model <adapt-mdl>                # Model to compute transforms with"
     echo "  --alignment-model <ali-mdl>              # Model to get Gaussian-level alignments for"
     echo "                                           # 1st pass of transform computation."
     echo "  --final-model <finald-mdl>               # Model to finally decode with"
     echo "  --si-dir <speaker-indep-decoding-dir>    # use this to skip 1st pass of decoding"
     echo "                                           # Caution-- must be with same tree"
     echo "  --acwt <acoustic-weight>                 # default 0.08333 ... used to get posteriors"
  
     exit 1;
  fi
  
  
  graphdir=$1
  data1=$2
  data2=$3
  dir=`echo $4 | sed 's:/$::g'` # remove any trailing slash.
  
  srcdir=`dirname $dir`; # Assume model directory one level up from decoding directory.
  
  mkdir -p $dir/log`
  
  sdata1=$data1/split$nj;
  sdata2=$data2/split$nj;
  [[ -d $sdata1 && $data1/feats.scp -ot $sdata1 ]] || split_data.sh $data1 $nj || exit 1;
  [[ -d $sdata2 && $data2/feats.scp -ot $sdata2 ]] || split_data.sh $data2 $nj || exit 1;
  
  echo $nj > $dir/num_jobs
  
  # Some checks.  Note: we don't need $srcdir/tree but we expect
  # it should exist, given the current structure of the scripts.
  for f in $graphdir/HCLG.fst $data1/feats.scp $data2/feats.scp $srcdir/tree; do
    [ ! -f $f ] && echo "$0: no such file $f" && exit 1;
  done
  
  
  ## Some checks, and setting of defaults for variables.
  [ "$nj" -ne "`cat $dir/num_jobs`" ] && echo "Mismatch in #jobs with si-dir" && exit 1;
  [ -z "$adapt_model" ] && adapt_model=$srcdir/final.mdl
  [ -z "$final_model" ] && final_model=$srcdir/final.mdl
  for f in $adapt_model $final_model; do
    [ ! -f $f ] && echo "$0: no such file $f" && exit 1;
  done
  ##
  
  
  # Set up features.
  
  splice_opts=`cat $srcdir/splice_opts 2>/dev/null` # frame-splicing options.
  normft2=`cat $srcdir/normft2 2>/dev/null`
  
  if [ -f $srcdir/final.mat ]; then feat_type=lda; else feat_type=delta; fi
  
  case $feat_type in
    delta) 
    	echo "$0: feature type is $feat_type"
    	;;
    lda) 
    	echo "$0: feature type is $feat_type"
      ;;
    *) echo "$0: invalid feature type $feat_type" && exit 1;
  esac
  
  # set up feature stream 1;  this are usually spectral features, so we will add
  # deltas or splice them
  feats1="ark,s,cs:apply-cmvn --norm-vars=false --utt2spk=ark:$sdata1/JOB/utt2spk scp:$sdata1/JOB/cmvn.scp scp:$sdata1/JOB/feats.scp ark:- |"
  
  if [ "$feat_type" == "delta" ]; then
    feats1="$feats1 add-deltas ark:- ark:- |"
  elif [ "$feat_type" == "lda" ]; then
    feats1="$feats1 splice-feats $splice_opts ark:- ark:- | transform-feats $srcdir/lda.mat ark:- ark:- |"
  fi
  
  # set up feature stream 2;  this are usually bottleneck or posterior features, 
  # which may be normalized if desired
  feats2="scp:$sdata2/JOB/feats.scp"
  
  if [ "$normft2" == "true" ]; then
    echo "Using cmvn for feats2"
    feats2="ark,s,cs:apply-cmvn --norm-vars=false --utt2spk=ark:$sdata2/JOB/utt2spk scp:$sdata2/JOB/cmvn.scp $feats2 ark:- |"
  fi
  
  # assemble tandem features
  sifeats="ark,s,cs:paste-feats '$feats1' '$feats2' ark:- |"
  
  # add transformation, if applicable
  if [ "$feat_type" == "lda" ]; then
    sifeats="$sifeats transform-feats $srcdir/final.mat ark:- ark:- |"
  fi
  
  if [ -e $dir/trans.1. ]; then
    echo "Using fMLLR transforms in $dir"
    feats="$sifeats transform-feats --utt2spk=ark:$sdata1/JOB/utt2spk ark:$dir/trans.JOB ark:- ark:- |"
  elif [ ! -z "$transform_dir" ]; then
    echo "$0: using transforms from $transform_dir"
    [ ! -f $transform_dir/trans.1 ] && echo "$0: no such file $transform_dir/trans.1" && exit 1;
    [ "$nj" -ne "`cat $transform_dir/num_jobs`" ] \
      && echo "$0: #jobs mismatch with transform-dir." && exit 1;
    feats="$sifeats transform-feats --utt2spk=ark:$sdata1/JOB/utt2spk ark,s,cs:$transform_dir/trans.JOB ark:- ark:- |"
  elif grep 'transform-feats --utt2spk' $srcdir/log/acc.0.1.log 2>/dev/null; then
    echo "$0: **WARNING**: you seem to be using an SGMM system trained with transforms,"
    echo "  but you are not providing the --transform-dir option in test time."
  fi
  
  
  # Rescore the state-level lattices with the final adapted features, and the final model
  # (which by default is $srcdir/final.mdl, but which may be specified on the command line,
  # useful in case of discriminatively trained systems).
  # At this point we prune and determinize the lattices and write them out, ready for 
  # language model rescoring.
  
  echo "Rescoring lattices, converting to slf"
  mkdir -p $dir/slf
  $cmd JOB=1:$nj $dir/log/rescore.slf.JOB.log \
    lattice-align-words $graphdir/phones/word_boundary.int $final_model "ark:gunzip -c $dir/lat.JOB.gz |" ark:- \| \
    gmm-rescore-lattice $final_model ark:- "$feats" ark,t:- \| \
    utils/int2sym.pl -f 3 $graphdir/words.txt \| \
    utils/convert_slf.pl - $dir/slf
  
  exit 0;