#!/bin/bash
  
  # Copyright 2012-2014  Johns Hopkins University (Author: Daniel Povey)
  #                      Vimal Manohar
  # Apache 2.0
  
  ##Changes
  # Vimal Manohar (Jan 2014):
  # Added options to boost silence probabilities in the model before
  # decoding. This can help in favoring the silence phones when 
  # some silence regions are wrongly decoded as speech phones like glottal stops
  
  # Begin configuration section.  
  transform_dir=
  iter=
  model= # You can specify the model to use (e.g. if you want to use the .alimdl)
  boost_silence=1.0         # Boost silence pdfs in the model by this factor before decoding
  silence_phones_list=      # List of silence phones that would be boosted before decoding
  stage=0
  nj=4
  cmd=run.pl
  max_active=7000
  beam=13.0
  lattice_beam=6.0
  acwt=0.083333 # note: only really affects pruning (scoring is on lattices).
  write_alignments=false  # The output directory is treated like an alignment directory
  write_words=true
  # End configuration section.
  
  echo "$0 $@"  # Print the command line for logging
  
  [ -f ./path.sh ] && . ./path.sh; # source the path.
  . parse_options.sh || exit 1;
  
  [ -z $silence_phones_list ] && boost_silence=1.0
  
  if [ $# != 3 ]; then
     echo "Usage: $0 [options] <graph-dir> <data-dir> <decode-dir>"
     echo "... where <decode-dir> is assumed to be a sub-directory of the directory"
     echo " where the model is.  This version produces just linear output, no lattices"
     echo ""
     echo "e.g.: steps/decode.sh exp/mono/graph_tgpr data/test_dev93 exp/mono/decode_dev93_tgpr"
     echo ""
     echo "This script works on CMN + (delta+delta-delta | LDA+MLLT) features; it works out"
     echo "what type of features you used (assuming it's one of these two)"
     echo ""
     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 "  --iter <iter>                                    # Iteration of model to test."
     echo "  --model <model>                                  # which model to use (e.g. to"
     echo "                                                   # specify the final.alimdl)"
     echo "  --write-alignments <true|false>                  # if true, output ali.*.gz"
     echo "  --write-words <true|false>                       # if true, output words.*.gz"
     echo "  --cmd (utils/run.pl|utils/queue.pl <queue opts>) # how to run jobs."
     echo "  --transform-dir <trans-dir>                      # dir to find fMLLR transforms "
     echo "  --acwt <float>                                   # acoustic scale used for lattice generation "
     exit 1;
  fi
  
  
  graphdir=$1
  data=$2
  dir=$3
  srcdir=`dirname $dir`; # The model directory is one level up from decoding directory.
  sdata=$data/split$nj;
  
  mkdir -p $dir/log
  [[ -d $sdata && $data/feats.scp -ot $sdata ]] || split_data.sh $data $nj || exit 1;
  echo $nj > $dir/num_jobs
  
  if [ -z "$model" ]; then # if --model <mdl> was not specified on the command line...
    if [ -z $iter ]; then model=$srcdir/final.mdl; 
    else model=$srcdir/$iter.mdl; fi
  fi
  
  for f in $sdata/1/feats.scp $sdata/1/cmvn.scp $model $graphdir/HCLG.fst; do
    [ ! -f $f ] && echo "decode.sh: no such file $f" && exit 1;
  done
  
  if [ -f $srcdir/final.mat ]; then feat_type=lda; else feat_type=delta; fi
  echo "decode.sh: feature type is $feat_type";
  
  splice_opts=`cat $srcdir/splice_opts 2>/dev/null`
  cmvn_opts=`cat $srcdir/cmvn_opts 2>/dev/null`
  delta_opts=`cat $srcdir/delta_opts 2>/dev/null`
  
  utils/lang/check_phones_compatible.sh $graphdir/phones.txt $srcdir/phones.txt || exit 1;
  
  if $write_alignments; then
    # Copy model and options that are generally expected in an alignment 
    # directory.
    cp $graphdir/phones.txt $dir || exit 1;
  
    cp $srcdir/{tree,final.mdl} $dir || exit 1;
    cp $srcdir/final.alimdl $dir 2>/dev/null
    cp $srcdir/final.occs $dir;
    cp $srcdir/splice_opts $dir 2>/dev/null # frame-splicing options.
    cp $srcdir/cmvn_opts $dir 2>/dev/null # cmn/cmvn option.
    cp $srcdir/delta_opts $dir 2>/dev/null
  fi
  
  case $feat_type in
    delta) feats="ark,s,cs:apply-cmvn $cmvn_opts --utt2spk=ark:$sdata/JOB/utt2spk scp:$sdata/JOB/cmvn.scp scp:$sdata/JOB/feats.scp ark:- | add-deltas $delta_opts ark:- ark:- |";;
    lda) feats="ark,s,cs:apply-cmvn $cmvn_opts --utt2spk=ark:$sdata/JOB/utt2spk scp:$sdata/JOB/cmvn.scp scp:$sdata/JOB/feats.scp ark:- | splice-feats $splice_opts ark:- ark:- | transform-feats $srcdir/final.mat ark:- ark:- |"
      if $write_alignments; then
        cp $srcdir/final.mat $dir
        cp $srcdir/full.mat $dir 2>/dev/null
      fi
      ;;
    *) echo "Invalid feature type $feat_type" && exit 1;
  esac
  if [ ! -z "$transform_dir" ]; then # add transforms to features...
    echo "Using fMLLR transforms from $transform_dir"
    [ ! -f $transform_dir/trans.1 ] && echo "Expected $transform_dir/trans.1 to exist."
    [ "`cat $transform_dir/num_jobs`" -ne $nj ] && \
       echo "Mismatch in number of jobs with $transform_dir";
    feats="$feats transform-feats --utt2spk=ark:$sdata/JOB/utt2spk ark:$transform_dir/trans.JOB ark:- ark:- |"
  fi
  
  if [ $stage -le 0 ]; then
    if $write_alignments; then
      ali="ark:|gzip -c > $dir/ali.JOB.gz"
    else
      ali="ark:/dev/null"
    fi
    if $write_words; then
      words="ark:|gzip -c > $dir/words.JOB.gz"
    else
      words="ark:/dev/null"
    fi
  
    [ ! -z "$silence_phones_list" ]  && \
      model="gmm-boost-silence --boost=$boost_silence $silence_phones_list $model - |"
  
    if [ -f "$graphdir/num_pdfs" ]; then
      [ "`cat $graphdir/num_pdfs`" -eq `am-info --print-args=false $model | grep pdfs | awk '{print $NF}'` ] || \
        { echo "Mismatch in number of pdfs with $model"; exit 1; }
    fi
    $cmd JOB=1:$nj $dir/log/decode.JOB.log \
      gmm-decode-faster --max-active=$max_active --beam=$beam  \
      --acoustic-scale=$acwt --allow-partial=true --word-symbol-table=$graphdir/words.txt \
      "$model" $graphdir/HCLG.fst "$feats" "$words" "$ali" || exit 1;
  fi
  
  exit 0;