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-rw-r--r--media/pocketsphinx/src/ngram_search_fwdtree.c1573
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diff --git a/media/pocketsphinx/src/ngram_search_fwdtree.c b/media/pocketsphinx/src/ngram_search_fwdtree.c
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--- a/media/pocketsphinx/src/ngram_search_fwdtree.c
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@@ -1,1573 +0,0 @@
-/* -*- c-basic-offset: 4; indent-tabs-mode: nil -*- */
-/* ====================================================================
- * Copyright (c) 2008 Carnegie Mellon University. All rights
- * reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * This work was supported in part by funding from the Defense Advanced
- * Research Projects Agency and the National Science Foundation of the
- * United States of America, and the CMU Sphinx Speech Consortium.
- *
- * THIS SOFTWARE IS PROVIDED BY CARNEGIE MELLON UNIVERSITY ``AS IS'' AND
- * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY
- * NOR ITS EMPLOYEES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- * ====================================================================
- *
- */
-
-/**
- * @file ngram_search_fwdtree.c Lexicon tree search.
- */
-
-/* System headers. */
-#include <string.h>
-#include <assert.h>
-
-/* SphinxBase headers. */
-#include <sphinxbase/ckd_alloc.h>
-#include <sphinxbase/listelem_alloc.h>
-#include <sphinxbase/err.h>
-
-/* Local headers. */
-#include "ngram_search_fwdtree.h"
-#include "phone_loop_search.h"
-
-/* Turn this on to dump channels for debugging */
-#define __CHAN_DUMP__ 0
-#if __CHAN_DUMP__
-#define chan_v_eval(chan) hmm_dump_vit_eval(&(chan)->hmm, stderr)
-#else
-#define chan_v_eval(chan) hmm_vit_eval(&(chan)->hmm)
-#endif
-
-/*
- * Allocate that part of the search channel tree structure that is independent of the
- * LM in use.
- */
-static void
-init_search_tree(ngram_search_t *ngs)
-{
- int32 w, ndiph, i, n_words, n_ci;
- dict_t *dict = ps_search_dict(ngs);
- bitvec_t *dimap;
-
- n_words = ps_search_n_words(ngs);
- ngs->homophone_set = ckd_calloc(n_words, sizeof(*ngs->homophone_set));
-
- /* Find #single phone words, and #unique first diphones (#root channels) in dict. */
- ndiph = 0;
- ngs->n_1ph_words = 0;
- n_ci = bin_mdef_n_ciphone(ps_search_acmod(ngs)->mdef);
- /* Allocate a bitvector with flags for each possible diphone. */
- dimap = bitvec_alloc(n_ci * n_ci);
- for (w = 0; w < n_words; w++) {
- if (!dict_real_word(dict, w))
- continue;
- if (dict_is_single_phone(dict, w))
- ++ngs->n_1ph_words;
- else {
- int ph0, ph1;
- ph0 = dict_first_phone(dict, w);
- ph1 = dict_second_phone(dict, w);
- /* Increment ndiph the first time we see a diphone. */
- if (bitvec_is_clear(dimap, ph0 * n_ci + ph1)) {
- bitvec_set(dimap, ph0 * n_ci + ph1);
- ++ndiph;
- }
- }
- }
- E_INFO("%d unique initial diphones\n", ndiph);
- bitvec_free(dimap);
-
- /* Add remaining dict words (</s>, <s>, <sil>, noise words) to single-phone words */
- ngs->n_1ph_words += dict_num_fillers(dict) + 2;
- ngs->n_root_chan_alloc = ndiph + 1;
- /* Verify that these are all *actually* single-phone words,
- * otherwise really bad things will happen to us. */
- for (w = 0; w < n_words; ++w) {
- if (dict_real_word(dict, w))
- continue;
- if (!dict_is_single_phone(dict, w)) {
- E_WARN("Filler word %d = %s has more than one phone, ignoring it.\n",
- w, dict_wordstr(dict, w));
- --ngs->n_1ph_words;
- }
- }
-
- /* Allocate and initialize root channels */
- ngs->root_chan =
- ckd_calloc(ngs->n_root_chan_alloc, sizeof(*ngs->root_chan));
- for (i = 0; i < ngs->n_root_chan_alloc; i++) {
- hmm_init(ngs->hmmctx, &ngs->root_chan[i].hmm, TRUE, -1, -1);
- ngs->root_chan[i].penult_phn_wid = -1;
- ngs->root_chan[i].next = NULL;
- }
-
- /* Permanently allocate and initialize channels for single-phone
- * words (1/word). */
- ngs->rhmm_1ph = ckd_calloc(ngs->n_1ph_words, sizeof(*ngs->rhmm_1ph));
- i = 0;
- for (w = 0; w < n_words; w++) {
- if (!dict_is_single_phone(dict, w))
- continue;
- /* Use SIL as right context for these. */
- ngs->rhmm_1ph[i].ci2phone = bin_mdef_silphone(ps_search_acmod(ngs)->mdef);
- ngs->rhmm_1ph[i].ciphone = dict_first_phone(dict, w);
- hmm_init(ngs->hmmctx, &ngs->rhmm_1ph[i].hmm, TRUE,
- bin_mdef_pid2ssid(ps_search_acmod(ngs)->mdef, ngs->rhmm_1ph[i].ciphone),
- bin_mdef_pid2tmatid(ps_search_acmod(ngs)->mdef, ngs->rhmm_1ph[i].ciphone));
- ngs->rhmm_1ph[i].next = NULL;
-
- ngs->word_chan[w] = (chan_t *) &(ngs->rhmm_1ph[i]);
- i++;
- }
-
- ngs->single_phone_wid = ckd_calloc(ngs->n_1ph_words,
- sizeof(*ngs->single_phone_wid));
- E_INFO("%d root, %d non-root channels, %d single-phone words\n",
- ngs->n_root_chan, ngs->n_nonroot_chan, ngs->n_1ph_words);
-}
-
-/*
- * One-time initialization of internal channels in HMM tree.
- */
-static void
-init_nonroot_chan(ngram_search_t *ngs, chan_t * hmm, int32 ph, int32 ci, int32 tmatid)
-{
- hmm->next = NULL;
- hmm->alt = NULL;
- hmm->info.penult_phn_wid = -1;
- hmm->ciphone = ci;
- hmm_init(ngs->hmmctx, &hmm->hmm, FALSE, ph, tmatid);
-}
-
-/*
- * Allocate and initialize search channel-tree structure.
- * At this point, all the root-channels have been allocated and partly initialized
- * (as per init_search_tree()), and channels for all the single-phone words have been
- * allocated and initialized. None of the interior channels of search-trees have
- * been allocated.
- * This routine may be called on every utterance, after reinit_search_tree() clears
- * the search tree created for the previous utterance. Meant for reconfiguring the
- * search tree to suit the currently active LM.
- */
-static void
-create_search_tree(ngram_search_t *ngs)
-{
- chan_t *hmm;
- root_chan_t *rhmm;
- int32 w, i, j, p, ph, tmatid;
- int32 n_words;
- dict_t *dict = ps_search_dict(ngs);
- dict2pid_t *d2p = ps_search_dict2pid(ngs);
-
- n_words = ps_search_n_words(ngs);
-
- E_INFO("Creating search tree\n");
-
- for (w = 0; w < n_words; w++)
- ngs->homophone_set[w] = -1;
-
- E_INFO("before: %d root, %d non-root channels, %d single-phone words\n",
- ngs->n_root_chan, ngs->n_nonroot_chan, ngs->n_1ph_words);
-
- ngs->n_1ph_LMwords = 0;
- ngs->n_root_chan = 0;
- ngs->n_nonroot_chan = 0;
-
- for (w = 0; w < n_words; w++) {
- int ciphone, ci2phone;
-
- /* Ignore dictionary words not in LM */
- if (!ngram_model_set_known_wid(ngs->lmset, dict_basewid(dict, w)))
- continue;
-
- /* Handle single-phone words individually; not in channel tree */
- if (dict_is_single_phone(dict, w)) {
- E_DEBUG(1,("single_phone_wid[%d] = %s\n",
- ngs->n_1ph_LMwords, dict_wordstr(dict, w)));
- ngs->single_phone_wid[ngs->n_1ph_LMwords++] = w;
- continue;
- }
-
- /* Find a root channel matching the initial diphone, or
- * allocate one if not found. */
- ciphone = dict_first_phone(dict, w);
- ci2phone = dict_second_phone(dict, w);
- for (i = 0; i < ngs->n_root_chan; ++i) {
- if (ngs->root_chan[i].ciphone == ciphone
- && ngs->root_chan[i].ci2phone == ci2phone)
- break;
- }
- if (i == ngs->n_root_chan) {
- rhmm = &(ngs->root_chan[ngs->n_root_chan]);
- rhmm->hmm.tmatid = bin_mdef_pid2tmatid(ps_search_acmod(ngs)->mdef, ciphone);
- /* Begin with CI phone? Not sure this makes a difference... */
- hmm_mpx_ssid(&rhmm->hmm, 0) =
- bin_mdef_pid2ssid(ps_search_acmod(ngs)->mdef, ciphone);
- rhmm->ciphone = ciphone;
- rhmm->ci2phone = ci2phone;
- ngs->n_root_chan++;
- }
- else
- rhmm = &(ngs->root_chan[i]);
-
- E_DEBUG(3,("word %s rhmm %d\n", dict_wordstr(dict, w), rhmm - ngs->root_chan));
- /* Now, rhmm = root channel for w. Go on to remaining phones */
- if (dict_pronlen(dict, w) == 2) {
- /* Next phone is the last; not kept in tree; add w to penult_phn_wid set */
- if ((j = rhmm->penult_phn_wid) < 0)
- rhmm->penult_phn_wid = w;
- else {
- for (; ngs->homophone_set[j] >= 0; j = ngs->homophone_set[j]);
- ngs->homophone_set[j] = w;
- }
- }
- else {
- /* Add remaining phones, except the last, to tree */
- ph = dict2pid_internal(d2p, w, 1);
- tmatid = bin_mdef_pid2tmatid(ps_search_acmod(ngs)->mdef, dict_pron(dict, w, 1));
- hmm = rhmm->next;
- if (hmm == NULL) {
- rhmm->next = hmm = listelem_malloc(ngs->chan_alloc);
- init_nonroot_chan(ngs, hmm, ph, dict_pron(dict, w, 1), tmatid);
- ngs->n_nonroot_chan++;
- }
- else {
- chan_t *prev_hmm = NULL;
-
- for (; hmm && (hmm_nonmpx_ssid(&hmm->hmm) != ph); hmm = hmm->alt)
- prev_hmm = hmm;
- if (!hmm) { /* thanks, rkm! */
- prev_hmm->alt = hmm = listelem_malloc(ngs->chan_alloc);
- init_nonroot_chan(ngs, hmm, ph, dict_pron(dict, w, 1), tmatid);
- ngs->n_nonroot_chan++;
- }
- }
- E_DEBUG(3,("phone %s = %d\n",
- bin_mdef_ciphone_str(ps_search_acmod(ngs)->mdef,
- dict_second_phone(dict, w)), ph));
- for (p = 2; p < dict_pronlen(dict, w) - 1; p++) {
- ph = dict2pid_internal(d2p, w, p);
- tmatid = bin_mdef_pid2tmatid(ps_search_acmod(ngs)->mdef, dict_pron(dict, w, p));
- if (!hmm->next) {
- hmm->next = listelem_malloc(ngs->chan_alloc);
- hmm = hmm->next;
- init_nonroot_chan(ngs, hmm, ph, dict_pron(dict, w, p), tmatid);
- ngs->n_nonroot_chan++;
- }
- else {
- chan_t *prev_hmm = NULL;
-
- for (hmm = hmm->next; hmm && (hmm_nonmpx_ssid(&hmm->hmm) != ph);
- hmm = hmm->alt)
- prev_hmm = hmm;
- if (!hmm) { /* thanks, rkm! */
- prev_hmm->alt = hmm = listelem_malloc(ngs->chan_alloc);
- init_nonroot_chan(ngs, hmm, ph, dict_pron(dict, w, p), tmatid);
- ngs->n_nonroot_chan++;
- }
- }
- E_DEBUG(3,("phone %s = %d\n",
- bin_mdef_ciphone_str(ps_search_acmod(ngs)->mdef,
- dict_pron(dict, w, p)), ph));
- }
-
- /* All but last phone of w in tree; add w to hmm->info.penult_phn_wid set */
- if ((j = hmm->info.penult_phn_wid) < 0)
- hmm->info.penult_phn_wid = w;
- else {
- for (; ngs->homophone_set[j] >= 0; j = ngs->homophone_set[j]);
- ngs->homophone_set[j] = w;
- }
- }
- }
-
- ngs->n_1ph_words = ngs->n_1ph_LMwords;
-
- /* Add filler words to the array of 1ph words. */
- for (w = 0; w < n_words; ++w) {
- /* Skip anything that doesn't actually have a single phone. */
- if (!dict_is_single_phone(dict, w))
- continue;
- /* Also skip "real words" and things that are in the LM. */
- if (dict_real_word(dict, w))
- continue;
- if (ngram_model_set_known_wid(ngs->lmset, dict_basewid(dict, w)))
- continue;
- E_DEBUG(1,("single_phone_wid[%d] = %s\n",
- ngs->n_1ph_words, dict_wordstr(dict, w)));
- ngs->single_phone_wid[ngs->n_1ph_words++] = w;
- }
-
- if (ngs->n_nonroot_chan >= ngs->max_nonroot_chan) {
- /* Give some room for channels for new words added dynamically at run time */
- ngs->max_nonroot_chan = ngs->n_nonroot_chan + 128;
- E_INFO("after: max nonroot chan increased to %d\n", ngs->max_nonroot_chan);
-
- /* Free old active channel list array if any and allocate new one */
- if (ngs->active_chan_list)
- ckd_free_2d(ngs->active_chan_list);
- ngs->active_chan_list = ckd_calloc_2d(2, ngs->max_nonroot_chan,
- sizeof(**ngs->active_chan_list));
- }
-
- if (!ngs->n_root_chan)
- E_ERROR("No word from the language model has pronunciation in the dictionary\n");
-
- E_INFO("after: %d root, %d non-root channels, %d single-phone words\n",
- ngs->n_root_chan, ngs->n_nonroot_chan, ngs->n_1ph_words);
-}
-
-static void
-reinit_search_subtree(ngram_search_t *ngs, chan_t * hmm)
-{
- chan_t *child, *sibling;
-
- /* First free all children under hmm */
- for (child = hmm->next; child; child = sibling) {
- sibling = child->alt;
- reinit_search_subtree(ngs, child);
- }
-
- /* Now free hmm */
- hmm_deinit(&hmm->hmm);
- listelem_free(ngs->chan_alloc, hmm);
-}
-
-/*
- * Delete search tree by freeing all interior channels within search tree and
- * restoring root channel state to the init state (i.e., just after init_search_tree()).
- */
-static void
-reinit_search_tree(ngram_search_t *ngs)
-{
- int32 i;
- chan_t *hmm, *sibling;
-
- for (i = 0; i < ngs->n_root_chan; i++) {
- hmm = ngs->root_chan[i].next;
-
- while (hmm) {
- sibling = hmm->alt;
- reinit_search_subtree(ngs, hmm);
- hmm = sibling;
- }
-
- ngs->root_chan[i].penult_phn_wid = -1;
- ngs->root_chan[i].next = NULL;
- }
- ngs->n_nonroot_chan = 0;
-}
-
-void
-ngram_fwdtree_init(ngram_search_t *ngs)
-{
- /* Allocate bestbp_rc, lastphn_cand, last_ltrans */
- ngs->bestbp_rc = ckd_calloc(bin_mdef_n_ciphone(ps_search_acmod(ngs)->mdef),
- sizeof(*ngs->bestbp_rc));
- ngs->lastphn_cand = ckd_calloc(ps_search_n_words(ngs),
- sizeof(*ngs->lastphn_cand));
- init_search_tree(ngs);
- create_search_tree(ngs);
-}
-
-static void
-deinit_search_tree(ngram_search_t *ngs)
-{
- int i, w, n_words;
-
- n_words = ps_search_n_words(ngs);
- for (i = 0; i < ngs->n_root_chan_alloc; i++) {
- hmm_deinit(&ngs->root_chan[i].hmm);
- }
- if (ngs->rhmm_1ph) {
- for (i = w = 0; w < n_words; ++w) {
- if (!dict_is_single_phone(ps_search_dict(ngs), w))
- continue;
- hmm_deinit(&ngs->rhmm_1ph[i].hmm);
- ++i;
- }
- ckd_free(ngs->rhmm_1ph);
- ngs->rhmm_1ph = NULL;
- }
- ngs->n_root_chan = 0;
- ngs->n_root_chan_alloc = 0;
- ckd_free(ngs->root_chan);
- ngs->root_chan = NULL;
- ckd_free(ngs->single_phone_wid);
- ngs->single_phone_wid = NULL;
- ckd_free(ngs->homophone_set);
- ngs->homophone_set = NULL;
-}
-
-void
-ngram_fwdtree_deinit(ngram_search_t *ngs)
-{
- double n_speech = (double)ngs->n_tot_frame
- / cmd_ln_int32_r(ps_search_config(ngs), "-frate");
-
- E_INFO("TOTAL fwdtree %.2f CPU %.3f xRT\n",
- ngs->fwdtree_perf.t_tot_cpu,
- ngs->fwdtree_perf.t_tot_cpu / n_speech);
- E_INFO("TOTAL fwdtree %.2f wall %.3f xRT\n",
- ngs->fwdtree_perf.t_tot_elapsed,
- ngs->fwdtree_perf.t_tot_elapsed / n_speech);
-
- /* Reset non-root channels. */
- reinit_search_tree(ngs);
- /* Free the search tree. */
- deinit_search_tree(ngs);
- /* Free other stuff. */
- ngs->max_nonroot_chan = 0;
- ckd_free_2d(ngs->active_chan_list);
- ngs->active_chan_list = NULL;
- ckd_free(ngs->cand_sf);
- ngs->cand_sf = NULL;
- ckd_free(ngs->bestbp_rc);
- ngs->bestbp_rc = NULL;
- ckd_free(ngs->lastphn_cand);
- ngs->lastphn_cand = NULL;
-}
-
-int
-ngram_fwdtree_reinit(ngram_search_t *ngs)
-{
- /* Reset non-root channels. */
- reinit_search_tree(ngs);
- /* Free the search tree. */
- deinit_search_tree(ngs);
- /* Reallocate things that depend on the number of words. */
- ckd_free(ngs->lastphn_cand);
- ngs->lastphn_cand = ckd_calloc(ps_search_n_words(ngs),
- sizeof(*ngs->lastphn_cand));
- ckd_free(ngs->word_chan);
- ngs->word_chan = ckd_calloc(ps_search_n_words(ngs),
- sizeof(*ngs->word_chan));
- /* Rebuild the search tree. */
- init_search_tree(ngs);
- create_search_tree(ngs);
- return 0;
-}
-
-void
-ngram_fwdtree_start(ngram_search_t *ngs)
-{
- ps_search_t *base = (ps_search_t *)ngs;
- int32 i, w, n_words;
- root_chan_t *rhmm;
-
- n_words = ps_search_n_words(ngs);
-
- /* Reset utterance statistics. */
- memset(&ngs->st, 0, sizeof(ngs->st));
- ptmr_reset(&ngs->fwdtree_perf);
- ptmr_start(&ngs->fwdtree_perf);
-
- /* Reset backpointer table. */
- ngs->bpidx = 0;
- ngs->bss_head = 0;
-
- /* Reset word lattice. */
- for (i = 0; i < n_words; ++i)
- ngs->word_lat_idx[i] = NO_BP;
-
- /* Reset active HMM and word lists. */
- ngs->n_active_chan[0] = ngs->n_active_chan[1] = 0;
- ngs->n_active_word[0] = ngs->n_active_word[1] = 0;
-
- /* Reset scores. */
- ngs->best_score = 0;
- ngs->renormalized = 0;
-
- /* Reset other stuff. */
- for (i = 0; i < n_words; i++)
- ngs->last_ltrans[i].sf = -1;
- ngs->n_frame = 0;
-
- /* Clear the hypothesis string. */
- ckd_free(base->hyp_str);
- base->hyp_str = NULL;
-
- /* Reset the permanently allocated single-phone words, since they
- * may have junk left over in them from FWDFLAT. */
- for (i = 0; i < ngs->n_1ph_words; i++) {
- w = ngs->single_phone_wid[i];
- rhmm = (root_chan_t *) ngs->word_chan[w];
- hmm_clear(&rhmm->hmm);
- }
-
- /* Start search with <s>; word_chan[<s>] is permanently allocated */
- rhmm = (root_chan_t *) ngs->word_chan[dict_startwid(ps_search_dict(ngs))];
- hmm_clear(&rhmm->hmm);
- hmm_enter(&rhmm->hmm, 0, NO_BP, 0);
-}
-
-/*
- * Mark the active senones for all senones belonging to channels that are active in the
- * current frame.
- */
-static void
-compute_sen_active(ngram_search_t *ngs, int frame_idx)
-{
- root_chan_t *rhmm;
- chan_t *hmm, **acl;
- int32 i, w, *awl;
-
- acmod_clear_active(ps_search_acmod(ngs));
-
- /* Flag active senones for root channels */
- for (i = ngs->n_root_chan, rhmm = ngs->root_chan; i > 0; --i, rhmm++) {
- if (hmm_frame(&rhmm->hmm) == frame_idx)
- acmod_activate_hmm(ps_search_acmod(ngs), &rhmm->hmm);
- }
-
- /* Flag active senones for nonroot channels in HMM tree */
- i = ngs->n_active_chan[frame_idx & 0x1];
- acl = ngs->active_chan_list[frame_idx & 0x1];
- for (hmm = *(acl++); i > 0; --i, hmm = *(acl++)) {
- acmod_activate_hmm(ps_search_acmod(ngs), &hmm->hmm);
- }
-
- /* Flag active senones for individual word channels */
- i = ngs->n_active_word[frame_idx & 0x1];
- awl = ngs->active_word_list[frame_idx & 0x1];
- for (w = *(awl++); i > 0; --i, w = *(awl++)) {
- for (hmm = ngs->word_chan[w]; hmm; hmm = hmm->next) {
- acmod_activate_hmm(ps_search_acmod(ngs), &hmm->hmm);
- }
- }
- for (i = 0; i < ngs->n_1ph_words; i++) {
- w = ngs->single_phone_wid[i];
- rhmm = (root_chan_t *) ngs->word_chan[w];
-
- if (hmm_frame(&rhmm->hmm) == frame_idx)
- acmod_activate_hmm(ps_search_acmod(ngs), &rhmm->hmm);
- }
-}
-
-static void
-renormalize_scores(ngram_search_t *ngs, int frame_idx, int32 norm)
-{
- root_chan_t *rhmm;
- chan_t *hmm, **acl;
- int32 i, w, *awl;
-
- /* Renormalize root channels */
- for (i = ngs->n_root_chan, rhmm = ngs->root_chan; i > 0; --i, rhmm++) {
- if (hmm_frame(&rhmm->hmm) == frame_idx) {
- hmm_normalize(&rhmm->hmm, norm);
- }
- }
-
- /* Renormalize nonroot channels in HMM tree */
- i = ngs->n_active_chan[frame_idx & 0x1];
- acl = ngs->active_chan_list[frame_idx & 0x1];
- for (hmm = *(acl++); i > 0; --i, hmm = *(acl++)) {
- hmm_normalize(&hmm->hmm, norm);
- }
-
- /* Renormalize individual word channels */
- i = ngs->n_active_word[frame_idx & 0x1];
- awl = ngs->active_word_list[frame_idx & 0x1];
- for (w = *(awl++); i > 0; --i, w = *(awl++)) {
- for (hmm = ngs->word_chan[w]; hmm; hmm = hmm->next) {
- hmm_normalize(&hmm->hmm, norm);
- }
- }
- for (i = 0; i < ngs->n_1ph_words; i++) {
- w = ngs->single_phone_wid[i];
- rhmm = (root_chan_t *) ngs->word_chan[w];
- if (hmm_frame(&rhmm->hmm) == frame_idx) {
- hmm_normalize(&rhmm->hmm, norm);
- }
- }
-
- ngs->renormalized = TRUE;
-}
-
-static int32
-eval_root_chan(ngram_search_t *ngs, int frame_idx)
-{
- root_chan_t *rhmm;
- int32 i, bestscore;
-
- bestscore = WORST_SCORE;
- for (i = ngs->n_root_chan, rhmm = ngs->root_chan; i > 0; --i, rhmm++) {
- if (hmm_frame(&rhmm->hmm) == frame_idx) {
- int32 score = chan_v_eval(rhmm);
- if (score BETTER_THAN bestscore)
- bestscore = score;
- ++ngs->st.n_root_chan_eval;
- }
- }
- return (bestscore);
-}
-
-static int32
-eval_nonroot_chan(ngram_search_t *ngs, int frame_idx)
-{
- chan_t *hmm, **acl;
- int32 i, bestscore;
-
- i = ngs->n_active_chan[frame_idx & 0x1];
- acl = ngs->active_chan_list[frame_idx & 0x1];
- bestscore = WORST_SCORE;
- ngs->st.n_nonroot_chan_eval += i;
-
- for (hmm = *(acl++); i > 0; --i, hmm = *(acl++)) {
- int32 score = chan_v_eval(hmm);
- assert(hmm_frame(&hmm->hmm) == frame_idx);
- if (score BETTER_THAN bestscore)
- bestscore = score;
- }
-
- return bestscore;
-}
-
-static int32
-eval_word_chan(ngram_search_t *ngs, int frame_idx)
-{
- root_chan_t *rhmm;
- chan_t *hmm;
- int32 i, w, bestscore, *awl, j, k;
-
- k = 0;
- bestscore = WORST_SCORE;
- awl = ngs->active_word_list[frame_idx & 0x1];
-
- i = ngs->n_active_word[frame_idx & 0x1];
- for (w = *(awl++); i > 0; --i, w = *(awl++)) {
- assert(bitvec_is_set(ngs->word_active, w));
- bitvec_clear(ngs->word_active, w);
- assert(ngs->word_chan[w] != NULL);
-
- for (hmm = ngs->word_chan[w]; hmm; hmm = hmm->next) {
- int32 score;
-
- assert(hmm_frame(&hmm->hmm) == frame_idx);
- score = chan_v_eval(hmm);
- /*printf("eval word chan %d score %d\n", w, score); */
-
- if (score BETTER_THAN bestscore)
- bestscore = score;
-
- k++;
- }
- }
-
- /* Similarly for statically allocated single-phone words */
- j = 0;
- for (i = 0; i < ngs->n_1ph_words; i++) {
- int32 score;
-
- w = ngs->single_phone_wid[i];
- rhmm = (root_chan_t *) ngs->word_chan[w];
- if (hmm_frame(&rhmm->hmm) < frame_idx)
- continue;
-
- score = chan_v_eval(rhmm);
- /* printf("eval 1ph word chan %d score %d\n", w, score); */
- if (score BETTER_THAN bestscore && w != ps_search_finish_wid(ngs))
- bestscore = score;
-
- j++;
- }
-
- ngs->st.n_last_chan_eval += k + j;
- ngs->st.n_nonroot_chan_eval += k + j;
- ngs->st.n_word_lastchan_eval +=
- ngs->n_active_word[frame_idx & 0x1] + j;
-
- return bestscore;
-}
-
-static int32
-evaluate_channels(ngram_search_t *ngs, int16 const *senone_scores, int frame_idx)
-{
- int32 bs;
-
- hmm_context_set_senscore(ngs->hmmctx, senone_scores);
- ngs->best_score = eval_root_chan(ngs, frame_idx);
- if ((bs = eval_nonroot_chan(ngs, frame_idx)) BETTER_THAN ngs->best_score)
- ngs->best_score = bs;
- if ((bs = eval_word_chan(ngs, frame_idx)) BETTER_THAN ngs->best_score)
- ngs->best_score = bs;
- ngs->last_phone_best_score = bs;
-
- return ngs->best_score;
-}
-
-/*
- * Prune currently active root channels for next frame. Also, perform exit
- * transitions out of them and activate successors.
- * score[] of pruned root chan set to WORST_SCORE elsewhere.
- */
-static void
-prune_root_chan(ngram_search_t *ngs, int frame_idx)
-{
- root_chan_t *rhmm;
- chan_t *hmm;
- int32 i, nf, w;
- int32 thresh, newphone_thresh, lastphn_thresh, newphone_score;
- chan_t **nacl; /* next active list */
- lastphn_cand_t *candp;
- phone_loop_search_t *pls;
-
- nf = frame_idx + 1;
- thresh = ngs->best_score + ngs->dynamic_beam;
- newphone_thresh = ngs->best_score + ngs->pbeam;
- lastphn_thresh = ngs->best_score + ngs->lpbeam;
- nacl = ngs->active_chan_list[nf & 0x1];
- pls = (phone_loop_search_t *)ps_search_lookahead(ngs);
-
- for (i = 0, rhmm = ngs->root_chan; i < ngs->n_root_chan; i++, rhmm++) {
- E_DEBUG(3,("Root channel %d frame %d score %d thresh %d\n",
- i, hmm_frame(&rhmm->hmm), hmm_bestscore(&rhmm->hmm), thresh));
- /* First check if this channel was active in current frame */
- if (hmm_frame(&rhmm->hmm) < frame_idx)
- continue;
-
- if (hmm_bestscore(&rhmm->hmm) BETTER_THAN thresh) {
- hmm_frame(&rhmm->hmm) = nf; /* rhmm will be active in next frame */
- E_DEBUG(3,("Preserving root channel %d score %d\n", i, hmm_bestscore(&rhmm->hmm)));
- /* transitions out of this root channel */
- /* transition to all next-level channels in the HMM tree */
- newphone_score = hmm_out_score(&rhmm->hmm) + ngs->pip;
- if (pls != NULL || newphone_score BETTER_THAN newphone_thresh) {
- for (hmm = rhmm->next; hmm; hmm = hmm->alt) {
- int32 pl_newphone_score = newphone_score
- + phone_loop_search_score(pls, hmm->ciphone);
- if (pl_newphone_score BETTER_THAN newphone_thresh) {
- if ((hmm_frame(&hmm->hmm) < frame_idx)
- || (newphone_score BETTER_THAN hmm_in_score(&hmm->hmm))) {
- hmm_enter(&hmm->hmm, newphone_score,
- hmm_out_history(&rhmm->hmm), nf);
- *(nacl++) = hmm;
- }
- }
- }
- }
-
- /*
- * Transition to last phone of all words for which this is the
- * penultimate phone (the last phones may need multiple right contexts).
- * Remember to remove the temporary newword_penalty.
- */
- if (pls != NULL || newphone_score BETTER_THAN lastphn_thresh) {
- for (w = rhmm->penult_phn_wid; w >= 0;
- w = ngs->homophone_set[w]) {
- int32 pl_newphone_score = newphone_score
- + phone_loop_search_score
- (pls, dict_last_phone(ps_search_dict(ngs),w));
- E_DEBUG(3,("word %s newphone_score %d\n", dict_wordstr(ps_search_dict(ngs), w), newphone_score));
- if (pl_newphone_score BETTER_THAN lastphn_thresh) {
- candp = ngs->lastphn_cand + ngs->n_lastphn_cand;
- ngs->n_lastphn_cand++;
- candp->wid = w;
- candp->score =
- newphone_score - ngs->nwpen;
- candp->bp = hmm_out_history(&rhmm->hmm);
- }
- }
- }
- }
- }
- ngs->n_active_chan[nf & 0x1] = (int)(nacl - ngs->active_chan_list[nf & 0x1]);
-}
-
-/*
- * Prune currently active nonroot channels in HMM tree for next frame. Also, perform
- * exit transitions out of such channels and activate successors.
- */
-static void
-prune_nonroot_chan(ngram_search_t *ngs, int frame_idx)
-{
- chan_t *hmm, *nexthmm;
- int32 nf, w, i;
- int32 thresh, newphone_thresh, lastphn_thresh, newphone_score;
- chan_t **acl, **nacl; /* active list, next active list */
- lastphn_cand_t *candp;
- phone_loop_search_t *pls;
-
- nf = frame_idx + 1;
-
- thresh = ngs->best_score + ngs->dynamic_beam;
- newphone_thresh = ngs->best_score + ngs->pbeam;
- lastphn_thresh = ngs->best_score + ngs->lpbeam;
- pls = (phone_loop_search_t *)ps_search_lookahead(ngs);
-
- acl = ngs->active_chan_list[frame_idx & 0x1]; /* currently active HMMs in tree */
- nacl = ngs->active_chan_list[nf & 0x1] + ngs->n_active_chan[nf & 0x1];
-
- for (i = ngs->n_active_chan[frame_idx & 0x1], hmm = *(acl++); i > 0;
- --i, hmm = *(acl++)) {
- assert(hmm_frame(&hmm->hmm) >= frame_idx);
-
- if (hmm_bestscore(&hmm->hmm) BETTER_THAN thresh) {
- /* retain this channel in next frame */
- if (hmm_frame(&hmm->hmm) != nf) {
- hmm_frame(&hmm->hmm) = nf;
- *(nacl++) = hmm;
- }
-
- /* transition to all next-level channel in the HMM tree */
- newphone_score = hmm_out_score(&hmm->hmm) + ngs->pip;
- if (pls != NULL || newphone_score BETTER_THAN newphone_thresh) {
- for (nexthmm = hmm->next; nexthmm; nexthmm = nexthmm->alt) {
- int32 pl_newphone_score = newphone_score
- + phone_loop_search_score(pls, nexthmm->ciphone);
- if ((pl_newphone_score BETTER_THAN newphone_thresh)
- && ((hmm_frame(&nexthmm->hmm) < frame_idx)
- || (newphone_score
- BETTER_THAN hmm_in_score(&nexthmm->hmm)))) {
- if (hmm_frame(&nexthmm->hmm) != nf) {
- /* Keep this HMM on the active list */
- *(nacl++) = nexthmm;
- }
- hmm_enter(&nexthmm->hmm, newphone_score,
- hmm_out_history(&hmm->hmm), nf);
- }
- }
- }
-
- /*
- * Transition to last phone of all words for which this is the
- * penultimate phone (the last phones may need multiple right contexts).
- * Remember to remove the temporary newword_penalty.
- */
- if (pls != NULL || newphone_score BETTER_THAN lastphn_thresh) {
- for (w = hmm->info.penult_phn_wid; w >= 0;
- w = ngs->homophone_set[w]) {
- int32 pl_newphone_score = newphone_score
- + phone_loop_search_score
- (pls, dict_last_phone(ps_search_dict(ngs),w));
- if (pl_newphone_score BETTER_THAN lastphn_thresh) {
- candp = ngs->lastphn_cand + ngs->n_lastphn_cand;
- ngs->n_lastphn_cand++;
- candp->wid = w;
- candp->score =
- newphone_score - ngs->nwpen;
- candp->bp = hmm_out_history(&hmm->hmm);
- }
- }
- }
- }
- else if (hmm_frame(&hmm->hmm) != nf) {
- hmm_clear(&hmm->hmm);
- }
- }
- ngs->n_active_chan[nf & 0x1] = (int)(nacl - ngs->active_chan_list[nf & 0x1]);
-}
-
-/*
- * Execute the transition into the last phone for all candidates words emerging from
- * the HMM tree. Attach LM scores to such transitions.
- * (Executed after pruning root and non-root, but before pruning word-chan.)
- */
-static void
-last_phone_transition(ngram_search_t *ngs, int frame_idx)
-{
- int32 i, j, k, nf, bp, bpend, w;
- lastphn_cand_t *candp;
- int32 *nawl;
- int32 thresh;
- int32 bestscore, dscr;
- chan_t *hmm;
- bptbl_t *bpe;
- int32 n_cand_sf = 0;
-
- nf = frame_idx + 1;
- nawl = ngs->active_word_list[nf & 0x1];
- ngs->st.n_lastphn_cand_utt += ngs->n_lastphn_cand;
-
- /* For each candidate word (entering its last phone) */
- /* If best LM score and bp for candidate known use it, else sort cands by startfrm */
- for (i = 0, candp = ngs->lastphn_cand; i < ngs->n_lastphn_cand; i++, candp++) {
- int32 start_score;
-
- /* This can happen if recognition fails. */
- if (candp->bp == -1)
- continue;
- /* Backpointer entry for it. */
- bpe = &(ngs->bp_table[candp->bp]);
-
- /* Subtract starting score for candidate, leave it with only word score */
- start_score = ngram_search_exit_score
- (ngs, bpe, dict_first_phone(ps_search_dict(ngs), candp->wid));
- assert(start_score BETTER_THAN WORST_SCORE);
- candp->score -= start_score;
-
- /*
- * If this candidate not occurred in an earlier frame, prepare for finding
- * best transition score into last phone; sort by start frame.
- */
- /* i.e. if we don't have an entry in last_ltrans for this
- * <word,sf>, then create one */
- if (ngs->last_ltrans[candp->wid].sf != bpe->frame + 1) {
- /* Look for an entry in cand_sf matching the backpointer
- * for this candidate. */
- for (j = 0; j < n_cand_sf; j++) {
- if (ngs->cand_sf[j].bp_ef == bpe->frame)
- break;
- }
- /* Oh, we found one, so chain onto it. */
- if (j < n_cand_sf)
- candp->next = ngs->cand_sf[j].cand;
- else {
- /* Nope, let's make a new one, allocating cand_sf if necessary. */
- if (n_cand_sf >= ngs->cand_sf_alloc) {
- if (ngs->cand_sf_alloc == 0) {
- ngs->cand_sf =
- ckd_calloc(CAND_SF_ALLOCSIZE,
- sizeof(*ngs->cand_sf));
- ngs->cand_sf_alloc = CAND_SF_ALLOCSIZE;
- }
- else {
- ngs->cand_sf_alloc += CAND_SF_ALLOCSIZE;
- ngs->cand_sf = ckd_realloc(ngs->cand_sf,
- ngs->cand_sf_alloc
- * sizeof(*ngs->cand_sf));
- E_INFO("cand_sf[] increased to %d entries\n",
- ngs->cand_sf_alloc);
- }
- }
-
- /* Use the newly created cand_sf. */
- j = n_cand_sf++;
- candp->next = -1; /* End of the chain. */
- ngs->cand_sf[j].bp_ef = bpe->frame;
- }
- /* Update it to point to this candidate. */
- ngs->cand_sf[j].cand = i;
-
- ngs->last_ltrans[candp->wid].dscr = WORST_SCORE;
- ngs->last_ltrans[candp->wid].sf = bpe->frame + 1;
- }
- }
-
- /* Compute best LM score and bp for new cands entered in the sorted lists above */
- for (i = 0; i < n_cand_sf; i++) {
- /* For the i-th unique end frame... */
- bp = ngs->bp_table_idx[ngs->cand_sf[i].bp_ef];
- bpend = ngs->bp_table_idx[ngs->cand_sf[i].bp_ef + 1];
- for (bpe = &(ngs->bp_table[bp]); bp < bpend; bp++, bpe++) {
- if (!bpe->valid)
- continue;
- /* For each candidate at the start frame find bp->cand transition-score */
- for (j = ngs->cand_sf[i].cand; j >= 0; j = candp->next) {
- int32 n_used;
- candp = &(ngs->lastphn_cand[j]);
- dscr =
- ngram_search_exit_score
- (ngs, bpe, dict_first_phone(ps_search_dict(ngs), candp->wid));
- if (dscr BETTER_THAN WORST_SCORE) {
- assert(!dict_filler_word(ps_search_dict(ngs), candp->wid));
- dscr += ngram_tg_score(ngs->lmset,
- dict_basewid(ps_search_dict(ngs), candp->wid),
- bpe->real_wid,
- bpe->prev_real_wid,
- &n_used)>>SENSCR_SHIFT;
- }
-
- if (dscr BETTER_THAN ngs->last_ltrans[candp->wid].dscr) {
- ngs->last_ltrans[candp->wid].dscr = dscr;
- ngs->last_ltrans[candp->wid].bp = bp;
- }
- }
- }
- }
-
- /* Update best transitions for all candidates; also update best lastphone score */
- bestscore = ngs->last_phone_best_score;
- for (i = 0, candp = ngs->lastphn_cand; i < ngs->n_lastphn_cand; i++, candp++) {
- candp->score += ngs->last_ltrans[candp->wid].dscr;
- candp->bp = ngs->last_ltrans[candp->wid].bp;
-
- if (candp->score BETTER_THAN bestscore)
- bestscore = candp->score;
- }
- ngs->last_phone_best_score = bestscore;
-
- /* At this pt, we know the best entry score (with LM component) for all candidates */
- thresh = bestscore + ngs->lponlybeam;
- for (i = ngs->n_lastphn_cand, candp = ngs->lastphn_cand; i > 0; --i, candp++) {
- if (candp->score BETTER_THAN thresh) {
- w = candp->wid;
-
- ngram_search_alloc_all_rc(ngs, w);
-
- k = 0;
- for (hmm = ngs->word_chan[w]; hmm; hmm = hmm->next) {
- if ((hmm_frame(&hmm->hmm) < frame_idx)
- || (candp->score BETTER_THAN hmm_in_score(&hmm->hmm))) {
- assert(hmm_frame(&hmm->hmm) != nf);
- hmm_enter(&hmm->hmm,
- candp->score, candp->bp, nf);
- k++;
- }
- }
- if (k > 0) {
- assert(bitvec_is_clear(ngs->word_active, w));
- assert(!dict_is_single_phone(ps_search_dict(ngs), w));
- *(nawl++) = w;
- bitvec_set(ngs->word_active, w);
- }
- }
- }
- ngs->n_active_word[nf & 0x1] = (int)(nawl - ngs->active_word_list[nf & 0x1]);
-}
-
-/*
- * Prune currently active word channels for next frame. Also, perform exit
- * transitions out of such channels and active successors.
- */
-static void
-prune_word_chan(ngram_search_t *ngs, int frame_idx)
-{
- root_chan_t *rhmm;
- chan_t *hmm, *thmm;
- chan_t **phmmp; /* previous HMM-pointer */
- int32 nf, w, i, k;
- int32 newword_thresh, lastphn_thresh;
- int32 *awl, *nawl;
-
- nf = frame_idx + 1;
- newword_thresh = ngs->last_phone_best_score + ngs->wbeam;
- lastphn_thresh = ngs->last_phone_best_score + ngs->lponlybeam;
-
- awl = ngs->active_word_list[frame_idx & 0x1];
- nawl = ngs->active_word_list[nf & 0x1] + ngs->n_active_word[nf & 0x1];
-
- /* Dynamically allocated last channels of multi-phone words */
- for (i = ngs->n_active_word[frame_idx & 0x1], w = *(awl++); i > 0;
- --i, w = *(awl++)) {
- k = 0;
- phmmp = &(ngs->word_chan[w]);
- for (hmm = ngs->word_chan[w]; hmm; hmm = thmm) {
- assert(hmm_frame(&hmm->hmm) >= frame_idx);
-
- thmm = hmm->next;
- if (hmm_bestscore(&hmm->hmm) BETTER_THAN lastphn_thresh) {
- /* retain this channel in next frame */
- hmm_frame(&hmm->hmm) = nf;
- k++;
- phmmp = &(hmm->next);
-
- /* Could if ((! skip_alt_frm) || (frame_idx & 0x1)) the following */
- if (hmm_out_score(&hmm->hmm) BETTER_THAN newword_thresh) {
- /* can exit channel and recognize word */
- ngram_search_save_bp(ngs, frame_idx, w,
- hmm_out_score(&hmm->hmm),
- hmm_out_history(&hmm->hmm),
- hmm->info.rc_id);
- }
- }
- else if (hmm_frame(&hmm->hmm) == nf) {
- phmmp = &(hmm->next);
- }
- else {
- hmm_deinit(&hmm->hmm);
- listelem_free(ngs->chan_alloc, hmm);
- *phmmp = thmm;
- }
- }
- if ((k > 0) && (bitvec_is_clear(ngs->word_active, w))) {
- assert(!dict_is_single_phone(ps_search_dict(ngs), w));
- *(nawl++) = w;
- bitvec_set(ngs->word_active, w);
- }
- }
- ngs->n_active_word[nf & 0x1] = (int)(nawl - ngs->active_word_list[nf & 0x1]);
-
- /*
- * Prune permanently allocated single-phone channels.
- * NOTES: score[] of pruned channels set to WORST_SCORE elsewhere.
- */
- for (i = 0; i < ngs->n_1ph_words; i++) {
- w = ngs->single_phone_wid[i];
- rhmm = (root_chan_t *) ngs->word_chan[w];
- E_DEBUG(3,("Single phone word %s frame %d score %d thresh %d outscore %d nwthresh %d\n",
- dict_wordstr(ps_search_dict(ngs),w),
- hmm_frame(&rhmm->hmm), hmm_bestscore(&rhmm->hmm),
- lastphn_thresh, hmm_out_score(&rhmm->hmm), newword_thresh));
- if (hmm_frame(&rhmm->hmm) < frame_idx)
- continue;
- if (hmm_bestscore(&rhmm->hmm) BETTER_THAN lastphn_thresh) {
- hmm_frame(&rhmm->hmm) = nf;
-
- /* Could if ((! skip_alt_frm) || (frame_idx & 0x1)) the following */
- if (hmm_out_score(&rhmm->hmm) BETTER_THAN newword_thresh) {
- E_DEBUG(4,("Exiting single phone word %s with %d > %d, %d\n",
- dict_wordstr(ps_search_dict(ngs),w),
- hmm_out_score(&rhmm->hmm),
- lastphn_thresh, newword_thresh));
- ngram_search_save_bp(ngs, frame_idx, w,
- hmm_out_score(&rhmm->hmm),
- hmm_out_history(&rhmm->hmm), 0);
- }
- }
- }
-}
-
-static void
-prune_channels(ngram_search_t *ngs, int frame_idx)
-{
- /* Clear last phone candidate list. */
- ngs->n_lastphn_cand = 0;
- /* Set the dynamic beam based on maxhmmpf here. */
- ngs->dynamic_beam = ngs->beam;
- if (ngs->maxhmmpf != -1
- && ngs->st.n_root_chan_eval + ngs->st.n_nonroot_chan_eval > ngs->maxhmmpf) {
- /* Build a histogram to approximately prune them. */
- int32 bins[256], bw, nhmms, i;
- root_chan_t *rhmm;
- chan_t **acl, *hmm;
-
- /* Bins go from zero (best score) to edge of beam. */
- bw = -ngs->beam / 256;
- memset(bins, 0, sizeof(bins));
- /* For each active root channel. */
- for (i = 0, rhmm = ngs->root_chan; i < ngs->n_root_chan; i++, rhmm++) {
- int32 b;
-
- /* Put it in a bin according to its bestscore. */
- b = (ngs->best_score - hmm_bestscore(&rhmm->hmm)) / bw;
- if (b >= 256)
- b = 255;
- ++bins[b];
- }
- /* For each active non-root channel. */
- acl = ngs->active_chan_list[frame_idx & 0x1]; /* currently active HMMs in tree */
- for (i = ngs->n_active_chan[frame_idx & 0x1], hmm = *(acl++);
- i > 0; --i, hmm = *(acl++)) {
- int32 b;
-
- /* Put it in a bin according to its bestscore. */
- b = (ngs->best_score - hmm_bestscore(&hmm->hmm)) / bw;
- if (b >= 256)
- b = 255;
- ++bins[b];
- }
- /* Walk down the bins to find the new beam. */
- for (i = nhmms = 0; i < 256; ++i) {
- nhmms += bins[i];
- if (nhmms > ngs->maxhmmpf)
- break;
- }
- ngs->dynamic_beam = -(i * bw);
- }
-
- prune_root_chan(ngs, frame_idx);
- prune_nonroot_chan(ngs, frame_idx);
- last_phone_transition(ngs, frame_idx);
- prune_word_chan(ngs, frame_idx);
-}
-
-/*
- * Limit the number of word exits in each frame to maxwpf. And also limit the number of filler
- * words to 1.
- */
-static void
-bptable_maxwpf(ngram_search_t *ngs, int frame_idx)
-{
- int32 bp, n;
- int32 bestscr, worstscr;
- bptbl_t *bpe, *bestbpe, *worstbpe;
-
- /* Don't prune if no pruing. */
- if (ngs->maxwpf == -1 || ngs->maxwpf == ps_search_n_words(ngs))
- return;
-
- /* Allow only one filler word exit (the best) per frame */
- bestscr = (int32) 0x80000000;
- bestbpe = NULL;
- n = 0;
- for (bp = ngs->bp_table_idx[frame_idx]; bp < ngs->bpidx; bp++) {
- bpe = &(ngs->bp_table[bp]);
- if (dict_filler_word(ps_search_dict(ngs), bpe->wid)) {
- if (bpe->score BETTER_THAN bestscr) {
- bestscr = bpe->score;
- bestbpe = bpe;
- }
- bpe->valid = FALSE;
- n++; /* No. of filler words */
- }
- }
- /* Restore bestbpe to valid state */
- if (bestbpe != NULL) {
- bestbpe->valid = TRUE;
- --n;
- }
-
- /* Allow up to maxwpf best entries to survive; mark the remaining with valid = 0 */
- n = (ngs->bpidx
- - ngs->bp_table_idx[frame_idx]) - n; /* No. of entries after limiting fillers */
- for (; n > ngs->maxwpf; --n) {
- /* Find worst BPTable entry */
- worstscr = (int32) 0x7fffffff;
- worstbpe = NULL;
- for (bp = ngs->bp_table_idx[frame_idx]; (bp < ngs->bpidx); bp++) {
- bpe = &(ngs->bp_table[bp]);
- if (bpe->valid && (bpe->score WORSE_THAN worstscr)) {
- worstscr = bpe->score;
- worstbpe = bpe;
- }
- }
- /* FIXME: Don't panic! */
- if (worstbpe == NULL)
- E_FATAL("PANIC: No worst BPtable entry remaining\n");
- worstbpe->valid = FALSE;
- }
-}
-
-static void
-word_transition(ngram_search_t *ngs, int frame_idx)
-{
- int32 i, k, bp, w, nf;
- int32 rc;
- int32 thresh, newscore, pl_newscore;
- bptbl_t *bpe;
- root_chan_t *rhmm;
- struct bestbp_rc_s *bestbp_rc_ptr;
- phone_loop_search_t *pls;
- dict_t *dict = ps_search_dict(ngs);
- dict2pid_t *d2p = ps_search_dict2pid(ngs);
-
- /*
- * Transition to start of new word instances (HMM tree roots); but only if words
- * other than </s> finished here.
- * But, first, find the best starting score for each possible right context phone.
- */
- for (i = bin_mdef_n_ciphone(ps_search_acmod(ngs)->mdef) - 1; i >= 0; --i)
- ngs->bestbp_rc[i].score = WORST_SCORE;
- k = 0;
- pls = (phone_loop_search_t *)ps_search_lookahead(ngs);
- /* Ugh, this is complicated. Scan all word exits for this frame
- * (they have already been created by prune_word_chan()). */
- for (bp = ngs->bp_table_idx[frame_idx]; bp < ngs->bpidx; bp++) {
- bpe = &(ngs->bp_table[bp]);
- ngs->word_lat_idx[bpe->wid] = NO_BP;
-
- if (bpe->wid == ps_search_finish_wid(ngs))
- continue;
- k++;
-
- /* DICT2PID */
- /* Array of HMM scores corresponding to all the possible right
- * context expansions of the final phone. It's likely that a
- * lot of these are going to be missing, actually. */
- if (bpe->last2_phone == -1) { /* implies s_idx == -1 */
- /* No right context expansion. */
- for (rc = 0; rc < bin_mdef_n_ciphone(ps_search_acmod(ngs)->mdef); ++rc) {
- if (bpe->score BETTER_THAN ngs->bestbp_rc[rc].score) {
- E_DEBUG(4,("bestbp_rc[0] = %d lc %d\n",
- bpe->score, bpe->last_phone));
- ngs->bestbp_rc[rc].score = bpe->score;
- ngs->bestbp_rc[rc].path = bp;
- ngs->bestbp_rc[rc].lc = bpe->last_phone;
- }
- }
- }
- else {
- xwdssid_t *rssid = dict2pid_rssid(d2p, bpe->last_phone, bpe->last2_phone);
- int32 *rcss = &(ngs->bscore_stack[bpe->s_idx]);
- for (rc = 0; rc < bin_mdef_n_ciphone(ps_search_acmod(ngs)->mdef); ++rc) {
- if (rcss[rssid->cimap[rc]] BETTER_THAN ngs->bestbp_rc[rc].score) {
- E_DEBUG(4,("bestbp_rc[%d] = %d lc %d\n",
- rc, rcss[rssid->cimap[rc]], bpe->last_phone));
- ngs->bestbp_rc[rc].score = rcss[rssid->cimap[rc]];
- ngs->bestbp_rc[rc].path = bp;
- ngs->bestbp_rc[rc].lc = bpe->last_phone;
- }
- }
- }
- }
- if (k == 0)
- return;
-
- nf = frame_idx + 1;
- thresh = ngs->best_score + ngs->dynamic_beam;
- /*
- * Hypothesize successors to words finished in this frame.
- * Main dictionary, multi-phone words transition to HMM-trees roots.
- */
- for (i = ngs->n_root_chan, rhmm = ngs->root_chan; i > 0; --i, rhmm++) {
- bestbp_rc_ptr = &(ngs->bestbp_rc[rhmm->ciphone]);
-
- newscore = bestbp_rc_ptr->score + ngs->nwpen + ngs->pip;
- pl_newscore = newscore
- + phone_loop_search_score(pls, rhmm->ciphone);
- if (pl_newscore BETTER_THAN thresh) {
- if ((hmm_frame(&rhmm->hmm) < frame_idx)
- || (newscore BETTER_THAN hmm_in_score(&rhmm->hmm))) {
- hmm_enter(&rhmm->hmm, newscore,
- bestbp_rc_ptr->path, nf);
- /* DICT2PID: Another place where mpx ssids are entered. */
- /* Look up the ssid to use when entering this mpx triphone. */
- hmm_mpx_ssid(&rhmm->hmm, 0) =
- dict2pid_ldiph_lc(d2p, rhmm->ciphone, rhmm->ci2phone, bestbp_rc_ptr->lc);
- assert(hmm_mpx_ssid(&rhmm->hmm, 0) != BAD_SSID);
- }
- }
- }
-
- /*
- * Single phone words; no right context for these. Cannot use bestbp_rc as
- * LM scores have to be included. First find best transition to these words.
- */
- for (i = 0; i < ngs->n_1ph_LMwords; i++) {
- w = ngs->single_phone_wid[i];
- ngs->last_ltrans[w].dscr = (int32) 0x80000000;
- }
- for (bp = ngs->bp_table_idx[frame_idx]; bp < ngs->bpidx; bp++) {
- bpe = &(ngs->bp_table[bp]);
- if (!bpe->valid)
- continue;
-
- for (i = 0; i < ngs->n_1ph_LMwords; i++) {
- int32 n_used;
- w = ngs->single_phone_wid[i];
- newscore = ngram_search_exit_score
- (ngs, bpe, dict_first_phone(dict, w));
- E_DEBUG(4, ("initial newscore for %s: %d\n",
- dict_wordstr(dict, w), newscore));
- if (newscore != WORST_SCORE)
- newscore += ngram_tg_score(ngs->lmset,
- dict_basewid(dict, w),
- bpe->real_wid,
- bpe->prev_real_wid,
- &n_used)>>SENSCR_SHIFT;
-
- /* FIXME: Not sure how WORST_SCORE could be better, but it
- * apparently happens. */
- if (newscore BETTER_THAN ngs->last_ltrans[w].dscr) {
- ngs->last_ltrans[w].dscr = newscore;
- ngs->last_ltrans[w].bp = bp;
- }
- }
- }
-
- /* Now transition to in-LM single phone words */
- for (i = 0; i < ngs->n_1ph_LMwords; i++) {
- w = ngs->single_phone_wid[i];
- /* Never transition into the start word (for one thing, it is
- a non-event in the language model.) */
- if (w == dict_startwid(ps_search_dict(ngs)))
- continue;
- rhmm = (root_chan_t *) ngs->word_chan[w];
- newscore = ngs->last_ltrans[w].dscr + ngs->pip;
- pl_newscore = newscore + phone_loop_search_score(pls, rhmm->ciphone);
- if (pl_newscore BETTER_THAN thresh) {
- bpe = ngs->bp_table + ngs->last_ltrans[w].bp;
- if ((hmm_frame(&rhmm->hmm) < frame_idx)
- || (newscore BETTER_THAN hmm_in_score(&rhmm->hmm))) {
- hmm_enter(&rhmm->hmm,
- newscore, ngs->last_ltrans[w].bp, nf);
- /* DICT2PID: another place where mpx ssids are entered. */
- /* Look up the ssid to use when entering this mpx triphone. */
- hmm_mpx_ssid(&rhmm->hmm, 0) =
- dict2pid_ldiph_lc(d2p, rhmm->ciphone, rhmm->ci2phone,
- dict_last_phone(dict, bpe->wid));
- assert(hmm_mpx_ssid(&rhmm->hmm, 0) != BAD_SSID);
- }
- }
- }
-
- /* Remaining words: <sil>, noise words. No mpx for these! */
- w = ps_search_silence_wid(ngs);
- rhmm = (root_chan_t *) ngs->word_chan[w];
- bestbp_rc_ptr = &(ngs->bestbp_rc[ps_search_acmod(ngs)->mdef->sil]);
- newscore = bestbp_rc_ptr->score + ngs->silpen + ngs->pip;
- pl_newscore = newscore
- + phone_loop_search_score(pls, rhmm->ciphone);
- if (pl_newscore BETTER_THAN thresh) {
- if ((hmm_frame(&rhmm->hmm) < frame_idx)
- || (newscore BETTER_THAN hmm_in_score(&rhmm->hmm))) {
- hmm_enter(&rhmm->hmm,
- newscore, bestbp_rc_ptr->path, nf);
- }
- }
- for (w = dict_filler_start(dict); w <= dict_filler_end(dict); w++) {
- if (w == ps_search_silence_wid(ngs))
- continue;
- /* Never transition into the start word (for one thing, it is
- a non-event in the language model.) */
- if (w == dict_startwid(ps_search_dict(ngs)))
- continue;
- rhmm = (root_chan_t *) ngs->word_chan[w];
- /* If this was not actually a single-phone word, rhmm will be NULL. */
- if (rhmm == NULL)
- continue;
- newscore = bestbp_rc_ptr->score + ngs->fillpen + ngs->pip;
- pl_newscore = newscore
- + phone_loop_search_score(pls, rhmm->ciphone);
- if (pl_newscore BETTER_THAN thresh) {
- if ((hmm_frame(&rhmm->hmm) < frame_idx)
- || (newscore BETTER_THAN hmm_in_score(&rhmm->hmm))) {
- hmm_enter(&rhmm->hmm,
- newscore, bestbp_rc_ptr->path, nf);
- }
- }
- }
-}
-
-static void
-deactivate_channels(ngram_search_t *ngs, int frame_idx)
-{
- root_chan_t *rhmm;
- int i;
-
- /* Clear score[] of pruned root channels */
- for (i = ngs->n_root_chan, rhmm = ngs->root_chan; i > 0; --i, rhmm++) {
- if (hmm_frame(&rhmm->hmm) == frame_idx) {
- hmm_clear(&rhmm->hmm);
- }
- }
- /* Clear score[] of pruned single-phone channels */
- for (i = 0; i < ngs->n_1ph_words; i++) {
- int32 w = ngs->single_phone_wid[i];
- rhmm = (root_chan_t *) ngs->word_chan[w];
- if (hmm_frame(&rhmm->hmm) == frame_idx) {
- hmm_clear(&rhmm->hmm);
- }
- }
-}
-
-int
-ngram_fwdtree_search(ngram_search_t *ngs, int frame_idx)
-{
- int16 const *senscr;
-
- /* Activate our HMMs for the current frame if need be. */
- if (!ps_search_acmod(ngs)->compallsen)
- compute_sen_active(ngs, frame_idx);
-
- /* Compute GMM scores for the current frame. */
- if ((senscr = acmod_score(ps_search_acmod(ngs), &frame_idx)) == NULL)
- return 0;
- ngs->st.n_senone_active_utt += ps_search_acmod(ngs)->n_senone_active;
-
- /* Mark backpointer table for current frame. */
- ngram_search_mark_bptable(ngs, frame_idx);
-
- /* If the best score is equal to or worse than WORST_SCORE,
- * recognition has failed, don't bother to keep trying. */
- if (ngs->best_score == WORST_SCORE || ngs->best_score WORSE_THAN WORST_SCORE)
- return 0;
- /* Renormalize if necessary */
- if (ngs->best_score + (2 * ngs->beam) WORSE_THAN WORST_SCORE) {
- E_INFO("Renormalizing Scores at frame %d, best score %d\n",
- frame_idx, ngs->best_score);
- renormalize_scores(ngs, frame_idx, ngs->best_score);
- }
-
- /* Evaluate HMMs */
- evaluate_channels(ngs, senscr, frame_idx);
- /* Prune HMMs and do phone transitions. */
- prune_channels(ngs, frame_idx);
- /* Do absolute pruning on word exits. */
- bptable_maxwpf(ngs, frame_idx);
- /* Do word transitions. */
- word_transition(ngs, frame_idx);
- /* Deactivate pruned HMMs. */
- deactivate_channels(ngs, frame_idx);
-
- ++ngs->n_frame;
- /* Return the number of frames processed. */
- return 1;
-}
-
-void
-ngram_fwdtree_finish(ngram_search_t *ngs)
-{
- int32 i, w, cf, *awl;
- root_chan_t *rhmm;
- chan_t *hmm, **acl;
-
- /* This is the number of frames processed. */
- cf = ps_search_acmod(ngs)->output_frame;
- /* Add a mark in the backpointer table for one past the final frame. */
- ngram_search_mark_bptable(ngs, cf);
-
- /* Deactivate channels lined up for the next frame */
- /* First, root channels of HMM tree */
- for (i = ngs->n_root_chan, rhmm = ngs->root_chan; i > 0; --i, rhmm++) {
- hmm_clear(&rhmm->hmm);
- }
-
- /* nonroot channels of HMM tree */
- i = ngs->n_active_chan[cf & 0x1];
- acl = ngs->active_chan_list[cf & 0x1];
- for (hmm = *(acl++); i > 0; --i, hmm = *(acl++)) {
- hmm_clear(&hmm->hmm);
- }
-
- /* word channels */
- i = ngs->n_active_word[cf & 0x1];
- awl = ngs->active_word_list[cf & 0x1];
- for (w = *(awl++); i > 0; --i, w = *(awl++)) {
- /* Don't accidentally free single-phone words! */
- if (dict_is_single_phone(ps_search_dict(ngs), w))
- continue;
- bitvec_clear(ngs->word_active, w);
- if (ngs->word_chan[w] == NULL)
- continue;
- ngram_search_free_all_rc(ngs, w);
- }
-
- /*
- * The previous search code did a postprocessing of the
- * backpointer table here, but we will postpone this until it is
- * absolutely necessary, i.e. when generating a word graph.
- * Likewise we don't actually have to decide what the exit word is
- * until somebody requests a backtrace.
- */
-
- ptmr_stop(&ngs->fwdtree_perf);
- /* Print out some statistics. */
- if (cf > 0) {
- double n_speech = (double)(cf + 1)
- / cmd_ln_int32_r(ps_search_config(ngs), "-frate");
- E_INFO("%8d words recognized (%d/fr)\n",
- ngs->bpidx, (ngs->bpidx + (cf >> 1)) / (cf + 1));
- E_INFO("%8d senones evaluated (%d/fr)\n", ngs->st.n_senone_active_utt,
- (ngs->st.n_senone_active_utt + (cf >> 1)) / (cf + 1));
- E_INFO("%8d channels searched (%d/fr), %d 1st, %d last\n",
- ngs->st.n_root_chan_eval + ngs->st.n_nonroot_chan_eval,
- (ngs->st.n_root_chan_eval + ngs->st.n_nonroot_chan_eval) / (cf + 1),
- ngs->st.n_root_chan_eval, ngs->st.n_last_chan_eval);
- E_INFO("%8d words for which last channels evaluated (%d/fr)\n",
- ngs->st.n_word_lastchan_eval,
- ngs->st.n_word_lastchan_eval / (cf + 1));
- E_INFO("%8d candidate words for entering last phone (%d/fr)\n",
- ngs->st.n_lastphn_cand_utt, ngs->st.n_lastphn_cand_utt / (cf + 1));
- E_INFO("fwdtree %.2f CPU %.3f xRT\n",
- ngs->fwdtree_perf.t_cpu,
- ngs->fwdtree_perf.t_cpu / n_speech);
- E_INFO("fwdtree %.2f wall %.3f xRT\n",
- ngs->fwdtree_perf.t_elapsed,
- ngs->fwdtree_perf.t_elapsed / n_speech);
- }
- /* dump_bptable(ngs); */
-}