/**
* Return average of N-beat outprob for pseudo state set.
*
* @param wrk [i/o] HMM computation work area
* @param t [in] input frame
* @param lset [in] pseudo state set
* @param param [in] input parameter data
*
* @return outprob log probability, average of top N states in @a lset.
*/
static LOGPROB
outprob_cd_nbest(HMMWork *wrk, int t, CD_State_Set *lset, HTK_Param *param)
{
LOGPROB prob;
int i, k, n;
n = 0;
for(i=0;i<lset->num;i++) {
prob = outprob_state(wrk, t, lset->s[i], param);
/*jlog("\t\t%d:%f\n", i, prob);*/
if (prob <= LOG_ZERO) continue;
if (n == 0 || prob <= wrk->cd_nbest_maxprobs[n-1]) {
if (n == wrk->cd_nbest_maxn) continue;
wrk->cd_nbest_maxprobs[n] = prob;
n++;
} else {
for(k=0; k<n; k++) {
if (prob > wrk->cd_nbest_maxprobs[k]) {
memmove(&(wrk->cd_nbest_maxprobs[k+1]), &(wrk->cd_nbest_maxprobs[k]),
sizeof(LOGPROB) * (n - k - ( (n == wrk->cd_nbest_maxn) ? 1 : 0)));
wrk->cd_nbest_maxprobs[k] = prob;
break;
}
}
if (n < wrk->cd_nbest_maxn) n++;
}
}
prob = 0.0;
for(i=0;i<n;i++) {
/*jlog("\t\t\t- %d: %f\n", i, wrk->cd_nbest_maxprobs[i]);*/
prob += wrk->cd_nbest_maxprobs[i];
}
return(prob/(float)n);
}
/**
* Top function to compute the output probability of a HMM state.
*
* @param wrk [i/o] HMM computation work area
* @param t [in] input frame
* @param hmmstate [in] HMM state
* @param param [in] input parameter data
*
* @return the computed log output probability.
*/
LOGPROB
outprob(HMMWork *wrk, int t, HMM_STATE *hmmstate, HTK_Param *param)
{
if (hmmstate->is_pseudo_state) {
return(outprob_cd(wrk, t, hmmstate->out.cdset, param));
} else {
return(outprob_state(wrk, t, hmmstate->out.state, param));
}
}
/**
* Return maximum outprob of the pseudo state set.
*
* @param wrk [i/o] HMM computation work area
* @param t [in] input frame
* @param lset [in] pseudo state set
* @param param [in] input parameter data
*
* @return maximum output log probability among states in @a lset.
*/
static LOGPROB
outprob_cd_max(HMMWork *wrk, int t, CD_State_Set *lset, HTK_Param *param)
{
LOGPROB maxprob, prob;
int i;
maxprob = LOG_ZERO;
for(i=0;i<lset->num;i++) {
prob = outprob_state(wrk, t, lset->s[i], param);
if (maxprob < prob) maxprob = prob;
}
return(maxprob);
}
/**
* Return average outprob of the pseudo state set.
*
* @param wrk [i/o] HMM computation work area
* @param t [in] input frame
* @param lset [in] pseudo state set
* @param param [in] input parameter data
*
* @return average output log probability of states in @a lset.
*/
static LOGPROB
outprob_cd_avg(HMMWork *wrk, int t, CD_State_Set *lset, HTK_Param *param)
{
LOGPROB sum, p;
int i,j;
sum = 0.0;
j = 0;
for(i=0;i<lset->num;i++) {
p = outprob_state(wrk, t, lset->s[i], param);
if (p > LOG_ZERO) {
sum += p;
j++;
}
}
return(sum/(float)j);
}
/**
* <JA>
* 木構造化辞書上の状態の出力確率を計算する.
*
* @param wchmm [in] 木構造化辞書情報
* @param node [in] ノード番号
* @param last_wid [in] 直前単語（単語先頭のトライフォン計算に用いる）
* @param t [in] 時間フレーム
* @param param [in] 特徴量パラメータ構造体 (@a t 番目のベクトルについて計算する)
*
* @return 出力確率の対数値を返す.
* </JA>
* <EN>
* Calculate output probability on a tree lexion node. This function
* calculates log output probability of an input vector on time frame @a t
* in input paramter @a param at a node on tree lexicon.
*
* @param wchmm [in] tree lexicon structure
* @param node [in] node ID to compute the output probability
* @param last_wid [in] word ID of last word hypothesis (used when the node is
* within the word beginning phone and triphone is used.
* @param t [in] time frame of input vector in @a param to compute.
* @param param [in] input parameter structure
*
* @return the computed log probability.
* </EN>
* @callgraph
* @callergraph
*/
LOGPROB
outprob_style(WCHMM_INFO *wchmm, int node, int last_wid, int t, HTK_Param *param)
{
char rbuf[MAX_HMMNAME_LEN]; ///< Local workarea for HMM name conversion
#ifndef PASS1_IWCD
/* if cross-word triphone handling is disabled, we simply compute the
output prob of the state */
return(outprob_state(wchmm->hmmwrk, t, wchmm->state[node].out, param));
#else /* PASS1_IWCD */
/* state type and context cache is considered */
HMM_Logical *ohmm, *rhmm;
RC_INFO *rset;
LRC_INFO *lrset;
CD_Set *lcd;
WORD_INFO *winfo = wchmm->winfo;
HTK_HMM_INFO *hmminfo = wchmm->hmminfo;
/* the actual computation is different according to their context dependency
handling */
switch(wchmm->outstyle[node]) {
case AS_STATE:
/* normal state (word-internal or context-independent )*/
/* compute as usual */
return(outprob_state(wchmm->hmmwrk, t, wchmm->state[node].out.state, param));
case AS_LSET:
/* node in word end phone */
/* compute approximated value using the state set in pseudo phone */
return(outprob_cd(wchmm->hmmwrk, t, wchmm->state[node].out.lset, param));
case AS_RSET:
/* note in the beginning phone of word */
/* depends on the last word hypothesis to compute the actual triphone */
rset = wchmm->state[node].out.rset;
/* consult cache */
if (rset->cache.state == NULL || rset->lastwid_cache != last_wid) {
/* cache miss...calculate */
/* rset contains either defined biphone or pseudo biphone */
if (last_wid != WORD_INVALID) {
/* lookup triphone with left-context (= last phoneme) */
if ((ohmm = get_left_context_HMM(rset->hmm, (winfo->wseq[last_wid][winfo->wlen[last_wid]-1])->name, hmminfo)) != NULL) {
rhmm = ohmm;
} else {
/* if triphone not found, try to use the bi-phone itself */
rhmm = rset->hmm;
/* If the bi-phone is explicitly specified in hmmdefs/HMMList,
use it. if both triphone and biphone not found in user-given
hmmdefs/HMMList, use "pseudo" phone, as same as the end of word */
if (debug2_flag) {
if (rhmm->is_pseudo) {
error_missing_left_triphone(rset->hmm, (winfo->wseq[last_wid][winfo->wlen[last_wid]-1])->name);
}
}
}
} else {
/* if last word is WORD_INVALID try to use the bi-phone itself */
rhmm = rset->hmm;
/* If the bi-phone is explicitly specified in hmmdefs/HMMList,
use it. if not, use "pseudo" phone, as same as the end of word */
if (debug2_flag) {
if (rhmm->is_pseudo) {
error_missing_left_triphone(rset->hmm, (winfo->wseq[last_wid][winfo->wlen[last_wid]-1])->name);
}
}
}
/* rhmm may be a pseudo phone */
/* store to cache */
if (rhmm->is_pseudo) {
rset->last_is_lset = TRUE;
rset->cache.lset = &(rhmm->body.pseudo->stateset[rset->state_loc]);
} else {
rset->last_is_lset = FALSE;
rset->cache.state = rhmm->body.defined->s[rset->state_loc];
}
rset->lastwid_cache = last_wid;
}
/* calculate outprob and return */
if (rset->last_is_lset) {
return(outprob_cd(wchmm->hmmwrk, t, rset->cache.lset, param));
} else {
return(outprob_state(wchmm->hmmwrk, t, rset->cache.state, param));
}
case AS_LRSET:
/* node in word with only one phoneme --- both beginning and end */
lrset = wchmm->state[node].out.lrset;
if (lrset->cache.state == NULL || lrset->lastwid_cache != last_wid) {
/* cache miss...calculate */
rhmm = lrset->hmm;
/* lookup cdset for given left context (= last phoneme) */
strcpy(rbuf, rhmm->name);
if (last_wid != WORD_INVALID) {
add_left_context(rbuf, (winfo->wseq[last_wid][winfo->wlen[last_wid]-1])->name);
}
if (wchmm->category_tree) {
#ifdef USE_OLD_IWCD
lcd = lcdset_lookup_by_hmmname(hmminfo, rbuf);
#else
/* use category-indexed cdset */
if (last_wid != WORD_INVALID &&
(ohmm = get_left_context_HMM(rhmm, (winfo->wseq[last_wid][winfo->wlen[last_wid]-1])->name, hmminfo)) != NULL) {
lcd = lcdset_lookup_with_category(wchmm, ohmm, lrset->category);
} else {
lcd = lcdset_lookup_with_category(wchmm, rhmm, lrset->category);
}
#endif
} else {
lcd = lcdset_lookup_by_hmmname(hmminfo, rbuf);
}
if (lcd != NULL) { /* found, set to cache */
lrset->last_is_lset = TRUE;
lrset->cache.lset = &(lcd->stateset[lrset->state_loc]);
lrset->lastwid_cache = last_wid;
} else {
/* no relating lcdset found, falling to normal state */
if (rhmm->is_pseudo) {
lrset->last_is_lset = TRUE;
lrset->cache.lset = &(rhmm->body.pseudo->stateset[lrset->state_loc]);
lrset->lastwid_cache = last_wid;
} else {
lrset->last_is_lset = FALSE;
lrset->cache.state = rhmm->body.defined->s[lrset->state_loc];
lrset->lastwid_cache = last_wid;
}
}
/*printf("[%s->%s]\n", lrset->hmm->name, rhmm->name);*/
}
/* calculate outprob and return */
if (lrset->last_is_lset) {
return(outprob_cd(wchmm->hmmwrk, t, lrset->cache.lset, param));
} else {
return(outprob_state(wchmm->hmmwrk, t, lrset->cache.state, param));
}
default:
/* should not happen */
j_internal_error("outprob_style: no outprob style??\n");
return(LOG_ZERO);
}
#endif /* PASS1_IWCD */
}
