#!/bin/bash
  # Copyright 2015-2017   David Snyder
  #           2015        Johns Hopkins University (Author: Daniel Garcia-Romero)
  #           2015        Johns Hopkins University (Author: Daniel Povey)
  # Apache 2.0
  
  # This script derives a full-covariance UBM from DNN posteriors and
  # speaker recognition features.
  
  # Begin configuration section.
  nj=8
  cmd="run.pl"
  stage=-2
  delta_window=3
  delta_order=2
  use_gpu=true
  nnet_job_opt=
  cleanup=true
  chunk_size=256
  stage=0
  # End configuration section.
  
  echo "$0 $@"  # Print the command line for logging
  
  if [ -f path.sh ]; then . ./path.sh; fi
  . parse_options.sh || exit 1;
  
  if [ $# != 4 ]; then
    echo "Usage: steps/init_full_ubm_from_dnn.sh <data-speaker-id> <data-dnn> <dnn-model> <new-ubm-dir>"
    echo "Initializes a full-covariance UBM from DNN posteriors and speaker recognition features."
    echo " e.g.: steps/init_full_ubm_from_dnn.sh data/train data/train_dnn exp/dnn/final.mdl exp/full_ubm"
    echo "main options (for others, see top of script file)"
    echo "  --config <config-file>                           # config containing options"
    echo "  --cmd (utils/run.pl|utils/queue.pl <queue opts>) # how to run jobs."
    echo "  --nj <n|16>                                      # number of parallel training jobs"
    echo "  --delta-window <n|3>                             # delta window size"
    echo "  --delta-order <n|2>                              # delta order"
    echo "  --use-gpu <true/false>                           # Use GPU to extract DNN posteriors"
    echo "  --chunk-size <n|256>                             # Number of frames processed at a time by the DNN"
    echo "  --nnet-job-opt <option|''>                       # Options for the DNN jobs which add to or"
    echo "                                                   # replace those specified by --cmd"
    exit 1;
  fi
  
  data=$1     # Features for the GMM
  data_dnn=$2 # Features for the DNN
  nnet=$3
  dir=$4
  
  gpu_opt=""
  nnet_job_opt=""
  if $use_gpu; then
    nnet_job_opt="$nnet_job_opt --gpu 1"
    gpu_opt="--use-gpu=yes"
    if ! cuda-compiled; then
      echo "$0: WARNING: you are trying to use the GPU but you have not compiled"
      echo "   for CUDA.  If you have GPUs and have nvcc installed, go to src/"
      echo "   and do ./configure; make"
      exit 1
    fi
  else
    echo "$0: without using a GPU this will be slow."
    gpu_opt="--use-gpu=no"
  fi
  
  
  for f in $data/feats.scp $data/vad.scp ${data_dnn}/feats.scp \
      ${data_dnn}/vad.scp $nnet; do
    [ ! -f $f ] && echo "No such file $f" && exit 1;
  done
  
  mkdir -p $dir/log
  echo $nj > $dir/num_jobs
  sdata=$data/split$nj;
  utils/split_data.sh $data $nj || exit 1;
  
  sdata_dnn=$data_dnn/split$nj;
  utils/split_data.sh $data_dnn $nj || exit 1;
  
  delta_opts="--delta-window=$delta_window --delta-order=$delta_order"
  echo $delta_opts > $dir/delta_opts
  
  logdir=$dir/log
  
  nnet_feats="ark,s,cs:apply-cmvn-sliding --center=true scp:$sdata_dnn/JOB/feats.scp ark:- |"
  
  feats="ark,s,cs:add-deltas $delta_opts scp:$sdata/JOB/feats.scp ark:- | \
  apply-cmvn-sliding --norm-vars=false --center=true --cmn-window=300 ark:- ark:- | \
  select-voiced-frames ark:- scp,s,cs:$sdata/JOB/vad.scp ark:- |"
  
  # Parse the output of nnet-am-info to find the size of the output layer
  # of the TDNN.  This will also correspond to the number of components
  # in the ancillary GMM.
  num_components=`grep -oP 'output-dim\ \K[0-9]+' <(nnet-am-info $nnet 2> /dev/null)`
  
  if [ $stage -le 0 ]; then
    echo "$0: accumulating stats from DNN posteriors and speaker ID features"
    for g in $(seq $nj); do
      $cmd $nnet_job_opt $dir/log/make_stats.$g.log \
      nnet-am-compute $gpu_opt \
        --chunk-size=${chunk_size} --apply-log=true $nnet \
        "`echo $nnet_feats | sed s/JOB/$g/g`" \
        ark:- \
        \| select-voiced-frames ark:- scp,s,cs:$sdata/$g/vad.scp ark:- \
        \| logprob-to-post ark:- ark:- \| \
        fgmm-global-acc-stats-post ark:- $num_components \
        "`echo $feats | sed s/JOB/$g/g`" \
        $dir/stats.$g.acc || exit 1 &
    done
    wait
  fi
  
  if [ $stage -le 1 ]; then
    echo "$0: initializing GMM from stats"
    $cmd $dir/log/init.log \
      fgmm-global-init-from-accs --verbose=2 \
      "fgmm-global-sum-accs - $dir/stats.*.acc |" $num_components \
      $dir/final.ubm || exit 1;
  fi
  
  if $cleanup; then
    echo "$0: removing stats"
    for g in $(seq $nj); do
      rm $dir/stats.$g.acc || exit 1
    done
  fi