1 files changed, 560 insertions, 0 deletions

diff --git a/media/sphinxbase/src/libsphinxbase/lm/lm3g_templates.c b/media/sphinxbase/src/libsphinxbase/lm/lm3g_templates.c
new file mode 100644
index 000000000..080cfa8e6
--- /dev/null
+++ b/media/sphinxbase/src/libsphinxbase/lm/lm3g_templates.c
@@ -0,0 +1,560 @@
+/* -*- c-basic-offset: 4; indent-tabs-mode: nil -*- */
+/* ====================================================================
+ * Copyright (c) 1999-2007 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 lm3g_templates.c Core Sphinx 3-gram code used in
+ * DMP/DMP32/ARPA (for now) model code.
+ */
+
+#include <assert.h>
+
+/* Locate a specific bigram within a bigram list */
+#define BINARY_SEARCH_THRESH	16
+static int32
+find_bg(bigram_t * bg, int32 n, int32 w)
+{
+    int32 i, b, e;
+
+    /* Binary search until segment size < threshold */
+    b = 0;
+    e = n;
+    while (e - b > BINARY_SEARCH_THRESH) {
+        i = (b + e) >> 1;
+        if (bg[i].wid < w)
+            b = i + 1;
+        else if (bg[i].wid > w)
+            e = i;
+        else
+            return i;
+    }
+
+    /* Linear search within narrowed segment */
+    for (i = b; (i < e) && (bg[i].wid != w); i++);
+    return ((i < e) ? i : -1);
+}
+
+static int32
+lm3g_bg_score(NGRAM_MODEL_TYPE *model,
+              int32 lw1, int32 lw2, int32 *n_used)
+{
+    int32 i, n, b, score;
+    bigram_t *bg;
+
+    if (lw1 < 0 || model->base.n < 2) {
+        *n_used = 1;
+        return model->lm3g.unigrams[lw2].prob1.l;
+    }
+
+    b = FIRST_BG(model, lw1);
+    n = FIRST_BG(model, lw1 + 1) - b;
+    bg = model->lm3g.bigrams + b;
+
+    if ((i = find_bg(bg, n, lw2)) >= 0) {
+        /* Access mode = bigram */
+        *n_used = 2;
+        score = model->lm3g.prob2[bg[i].prob2].l;
+    }
+    else {
+        /* Access mode = unigram */
+        *n_used = 1;
+        score = model->lm3g.unigrams[lw1].bo_wt1.l + model->lm3g.unigrams[lw2].prob1.l;
+    }
+
+    return (score);
+}
+
+static void
+load_tginfo(NGRAM_MODEL_TYPE *model, int32 lw1, int32 lw2)
+{
+    int32 i, n, b, t;
+    bigram_t *bg;
+    tginfo_t *tginfo;
+
+    /* First allocate space for tg information for bg lw1,lw2 */
+    tginfo = (tginfo_t *) listelem_malloc(model->lm3g.le);
+    tginfo->w1 = lw1;
+    tginfo->tg = NULL;
+    tginfo->next = model->lm3g.tginfo[lw2];
+    model->lm3g.tginfo[lw2] = tginfo;
+
+    /* Locate bigram lw1,lw2 */
+    b = model->lm3g.unigrams[lw1].bigrams;
+    n = model->lm3g.unigrams[lw1 + 1].bigrams - b;
+    bg = model->lm3g.bigrams + b;
+
+    if ((n > 0) && ((i = find_bg(bg, n, lw2)) >= 0)) {
+        tginfo->bowt = model->lm3g.bo_wt2[bg[i].bo_wt2].l;
+
+        /* Find t = Absolute first trigram index for bigram lw1,lw2 */
+        b += i;                 /* b = Absolute index of bigram lw1,lw2 on disk */
+        t = FIRST_TG(model, b);
+
+        tginfo->tg = model->lm3g.trigrams + t;
+
+        /* Find #tg for bigram w1,w2 */
+        tginfo->n_tg = FIRST_TG(model, b + 1) - t;
+    }
+    else {                      /* No bigram w1,w2 */
+        tginfo->bowt = 0;
+        tginfo->n_tg = 0;
+    }
+}
+
+/* Similar to find_bg */
+static int32
+find_tg(trigram_t * tg, int32 n, uint32 w)
+{
+    int32 i, b, e;
+
+    b = 0;
+    e = n;
+    while (e - b > BINARY_SEARCH_THRESH) {
+        i = (b + e) >> 1;
+        if (tg[i].wid < w)
+            b = i + 1;
+        else if (tg[i].wid > w)
+            e = i;
+        else
+            return i;
+    }
+
+    for (i = b; (i < e) && (tg[i].wid != w); i++);
+    return ((i < e) ? i : -1);
+}
+
+static int32
+lm3g_tg_score(NGRAM_MODEL_TYPE *model, int32 lw1,
+              int32 lw2, int32 lw3, int32 *n_used)
+{
+    ngram_model_t *base = &model->base;
+    int32 i, n, score;
+    trigram_t *tg;
+    tginfo_t *tginfo, *prev_tginfo;
+
+    if ((base->n < 3) || (lw1 < 0) || (lw2 < 0))
+        return (lm3g_bg_score(model, lw2, lw3, n_used));
+
+    prev_tginfo = NULL;
+    for (tginfo = model->lm3g.tginfo[lw2]; tginfo; tginfo = tginfo->next) {
+        if (tginfo->w1 == lw1)
+            break;
+        prev_tginfo = tginfo;
+    }
+
+    if (!tginfo) {
+        load_tginfo(model, lw1, lw2);
+        tginfo = model->lm3g.tginfo[lw2];
+    }
+    else if (prev_tginfo) {
+        prev_tginfo->next = tginfo->next;
+        tginfo->next = model->lm3g.tginfo[lw2];
+        model->lm3g.tginfo[lw2] = tginfo;
+    }
+
+    tginfo->used = 1;
+
+    /* Trigrams for w1,w2 now pointed to by tginfo */
+    n = tginfo->n_tg;
+    tg = tginfo->tg;
+    if ((i = find_tg(tg, n, lw3)) >= 0) {
+        /* Access mode = trigram */
+        *n_used = 3;
+        score = model->lm3g.prob3[tg[i].prob3].l;
+    }
+    else {
+        score = tginfo->bowt + lm3g_bg_score(model, lw2, lw3, n_used);
+    }
+
+    return (score);
+}
+
+static int32
+lm3g_template_score(ngram_model_t *base, int32 wid,
+                      int32 *history, int32 n_hist,
+                      int32 *n_used)
+{
+    NGRAM_MODEL_TYPE *model = (NGRAM_MODEL_TYPE *)base;
+    switch (n_hist) {
+    case 0:
+        /* Access mode: unigram */
+        *n_used = 1;
+        return model->lm3g.unigrams[wid].prob1.l;
+    case 1:
+        return lm3g_bg_score(model, history[0], wid, n_used);
+    case 2:
+    default:
+        /* Anything greater than 2 is the same as a trigram for now. */
+        return lm3g_tg_score(model, history[1], history[0], wid, n_used);
+    }
+}
+
+static int32
+lm3g_template_raw_score(ngram_model_t *base, int32 wid,
+                        int32 *history, int32 n_hist,
+                          int32 *n_used)
+{
+    NGRAM_MODEL_TYPE *model = (NGRAM_MODEL_TYPE *)base;
+    int32 score;
+
+    switch (n_hist) {
+    case 0:
+        /* Access mode: unigram */
+        *n_used = 1;
+        /* Undo insertion penalty. */
+        score = model->lm3g.unigrams[wid].prob1.l - base->log_wip;
+        /* Undo language weight. */
+        score = (int32)(score / base->lw);
+        /* Undo unigram interpolation */
+        if (strcmp(base->word_str[wid], "<s>") != 0) { /* FIXME: configurable start_sym */
+            /* This operation is numerically unstable, so try to avoid it
+             * as possible */
+            if (base->log_uniform + base->log_uniform_weight > logmath_get_zero(base->lmath)) {
+               score = logmath_log(base->lmath,
+                            logmath_exp(base->lmath, score)
+                            - logmath_exp(base->lmath, 
+                                          base->log_uniform + base->log_uniform_weight));
+            }
+        }
+        return score;
+    case 1:
+        score = lm3g_bg_score(model, history[0], wid, n_used);
+        break;
+    case 2:
+    default:
+        /* Anything greater than 2 is the same as a trigram for now. */
+        score = lm3g_tg_score(model, history[1], history[0], wid, n_used);
+        break;
+    }
+    /* FIXME (maybe): This doesn't undo unigram weighting in backoff cases. */
+    return (int32)((score - base->log_wip) / base->lw);
+}
+
+static int32
+lm3g_template_add_ug(ngram_model_t *base,
+                       int32 wid, int32 lweight)
+{
+    NGRAM_MODEL_TYPE *model = (NGRAM_MODEL_TYPE *)base;
+    return lm3g_add_ug(base, &model->lm3g, wid, lweight);
+}
+
+static void
+lm3g_template_flush(ngram_model_t *base)
+{
+    NGRAM_MODEL_TYPE *model = (NGRAM_MODEL_TYPE *)base;
+    lm3g_tginfo_reset(base, &model->lm3g);
+}
+
+typedef struct lm3g_iter_s {
+    ngram_iter_t base;
+    unigram_t *ug;
+    bigram_t *bg;
+    trigram_t *tg;
+} lm3g_iter_t;
+
+static ngram_iter_t *
+lm3g_template_iter(ngram_model_t *base, int32 wid,
+                   int32 *history, int32 n_hist)
+{
+    NGRAM_MODEL_TYPE *model = (NGRAM_MODEL_TYPE *)base;
+    lm3g_iter_t *itor = (lm3g_iter_t *)ckd_calloc(1, sizeof(*itor));
+
+    ngram_iter_init((ngram_iter_t *)itor, base, n_hist, FALSE);
+
+    if (n_hist == 0) {
+        /* Unigram is the easiest. */
+        itor->ug = model->lm3g.unigrams + wid;
+        return (ngram_iter_t *)itor;
+    }
+    else if (n_hist == 1) {
+        int32 i, n, b;
+        /* Find the bigram, as in bg_score above (duplicate code...) */
+        itor->ug = model->lm3g.unigrams + history[0];
+        b = FIRST_BG(model, history[0]);
+        n = FIRST_BG(model, history[0] + 1) - b;
+        itor->bg = model->lm3g.bigrams + b;
+        /* If no such bigram exists then fail. */
+        if ((i = find_bg(itor->bg, n, wid)) < 0) {
+            ngram_iter_free((ngram_iter_t *)itor);
+            return NULL;
+        }
+        itor->bg += i;
+        return (ngram_iter_t *)itor;
+    }
+    else if (n_hist == 2) {
+        int32 i, n;
+        tginfo_t *tginfo, *prev_tginfo;
+        /* Find the trigram, as in tg_score above (duplicate code...) */
+        itor->ug = model->lm3g.unigrams + history[1];
+        prev_tginfo = NULL;
+        for (tginfo = model->lm3g.tginfo[history[0]];
+             tginfo; tginfo = tginfo->next) {
+            if (tginfo->w1 == history[1])
+                break;
+            prev_tginfo = tginfo;
+        }
+
+        if (!tginfo) {
+            load_tginfo(model, history[1], history[0]);
+            tginfo = model->lm3g.tginfo[history[0]];
+        }
+        else if (prev_tginfo) {
+            prev_tginfo->next = tginfo->next;
+            tginfo->next = model->lm3g.tginfo[history[0]];
+            model->lm3g.tginfo[history[0]] = tginfo;
+        }
+
+        tginfo->used = 1;
+
+        /* Trigrams for w1,w2 now pointed to by tginfo */
+        n = tginfo->n_tg;
+        itor->tg = tginfo->tg;
+        if ((i = find_tg(itor->tg, n, wid)) >= 0) {
+            itor->tg += i;
+            /* Now advance the bigram pointer accordingly.  FIXME:
+             * Note that we actually already found the relevant bigram
+             * in load_tginfo. */
+            itor->bg = model->lm3g.bigrams;
+            while (FIRST_TG(model, (itor->bg - model->lm3g.bigrams + 1))
+                   <= (itor->tg - model->lm3g.trigrams))
+                ++itor->bg;
+            return (ngram_iter_t *)itor;
+        }
+        else {
+            ngram_iter_free((ngram_iter_t *)itor);
+            return (ngram_iter_t *)NULL;
+        }
+    }
+    else {
+        /* Should not happen. */
+        assert(n_hist == 0); /* Guaranteed to fail. */
+        ngram_iter_free((ngram_iter_t *)itor);
+        return NULL;
+    }
+}
+
+static ngram_iter_t *
+lm3g_template_mgrams(ngram_model_t *base, int m)
+{
+    NGRAM_MODEL_TYPE *model = (NGRAM_MODEL_TYPE *)base;
+    lm3g_iter_t *itor = (lm3g_iter_t *)ckd_calloc(1, sizeof(*itor));
+    ngram_iter_init((ngram_iter_t *)itor, base, m, FALSE);
+
+    itor->ug = model->lm3g.unigrams;
+    itor->bg = model->lm3g.bigrams;
+    itor->tg = model->lm3g.trigrams;
+
+    /* Advance bigram pointer to match first trigram. */
+    if (m > 1 && base->n_counts[1] > 1)  {
+        while (FIRST_TG(model, (itor->bg - model->lm3g.bigrams + 1))
+               <= (itor->tg - model->lm3g.trigrams))
+            ++itor->bg;
+    }
+
+    /* Advance unigram pointer to match first bigram. */
+    if (m > 0 && base->n_counts[0] > 1) {
+        while (itor->ug[1].bigrams <= (itor->bg - model->lm3g.bigrams))
+            ++itor->ug;
+    }
+
+    return (ngram_iter_t *)itor;
+}
+
+static ngram_iter_t *
+lm3g_template_successors(ngram_iter_t *bitor)
+{
+    NGRAM_MODEL_TYPE *model = (NGRAM_MODEL_TYPE *)bitor->model;
+    lm3g_iter_t *from = (lm3g_iter_t *)bitor;
+    lm3g_iter_t *itor = (lm3g_iter_t *)ckd_calloc(1, sizeof(*itor));
+
+    itor->ug = from->ug;
+    switch (bitor->m) {
+    case 0:
+        /* Next itor bigrams is the same as this itor bigram or
+	   itor bigrams is more than total count. This means no successors */
+        if (((itor->ug + 1) - model->lm3g.unigrams < bitor->model->n_counts[0] &&
+	    itor->ug->bigrams == (itor->ug + 1)->bigrams) || 
+	    itor->ug->bigrams == bitor->model->n_counts[1])
+	    goto done;
+	    
+        /* Start iterating from first bigram successor of from->ug. */
+        itor->bg = model->lm3g.bigrams + itor->ug->bigrams;
+        break;
+    case 1:
+        itor->bg = from->bg;
+        
+        /* This indicates no successors */
+        if (((itor->bg + 1) - model->lm3g.bigrams < bitor->model->n_counts[1] &&
+    	    FIRST_TG (model, itor->bg - model->lm3g.bigrams) == 
+    	    FIRST_TG (model, (itor->bg + 1) - model->lm3g.bigrams)) ||
+	    FIRST_TG (model, itor->bg - model->lm3g.bigrams) == bitor->model->n_counts[2])
+    	    goto done;
+    	    
+        /* Start iterating from first trigram successor of from->bg. */
+        itor->tg = (model->lm3g.trigrams 
+                    + FIRST_TG(model, (itor->bg - model->lm3g.bigrams)));
+#if 0
+        printf("%s %s => %d (%s)\n",
+               model->base.word_str[itor->ug - model->lm3g.unigrams],
+               model->base.word_str[itor->bg->wid],
+               FIRST_TG(model, (itor->bg - model->lm3g.bigrams)),
+               model->base.word_str[itor->tg->wid]);
+#endif
+        break;
+    case 2:
+    default:
+        /* All invalid! */
+        goto done;
+    }
+
+    ngram_iter_init((ngram_iter_t *)itor, bitor->model, bitor->m + 1, TRUE);
+    return (ngram_iter_t *)itor;
+    done:
+        ckd_free(itor);
+        return NULL;
+}
+
+static int32 const *
+lm3g_template_iter_get(ngram_iter_t *base,
+                       int32 *out_score, int32 *out_bowt)
+{
+    NGRAM_MODEL_TYPE *model = (NGRAM_MODEL_TYPE *)base->model;
+    lm3g_iter_t *itor = (lm3g_iter_t *)base;
+
+    base->wids[0] = itor->ug - model->lm3g.unigrams;
+    if (itor->bg) base->wids[1] = itor->bg->wid;
+    if (itor->tg) base->wids[2] = itor->tg->wid;
+#if 0
+    printf("itor_get: %d %d %d\n", base->wids[0], base->wids[1], base->wids[2]);
+#endif
+
+    switch (base->m) {
+    case 0:
+        *out_score = itor->ug->prob1.l;
+        *out_bowt = itor->ug->bo_wt1.l;
+        break;
+    case 1:
+        *out_score = model->lm3g.prob2[itor->bg->prob2].l;
+        if (model->lm3g.bo_wt2)
+            *out_bowt = model->lm3g.bo_wt2[itor->bg->bo_wt2].l;
+        else
+            *out_bowt = 0;
+        break;
+    case 2:
+        *out_score = model->lm3g.prob3[itor->tg->prob3].l;
+        *out_bowt = 0;
+        break;
+    default: /* Should not happen. */
+        return NULL;
+    }
+    return base->wids;
+}
+
+static ngram_iter_t *
+lm3g_template_iter_next(ngram_iter_t *base)
+{
+    NGRAM_MODEL_TYPE *model = (NGRAM_MODEL_TYPE *)base->model;
+    lm3g_iter_t *itor = (lm3g_iter_t *)base;
+
+    switch (base->m) {
+    case 0:
+        ++itor->ug;
+        /* Check for end condition. */
+        if (itor->ug - model->lm3g.unigrams >= base->model->n_counts[0])
+            goto done;
+        break;
+    case 1:
+        ++itor->bg;
+        /* Check for end condition. */
+        if (itor->bg - model->lm3g.bigrams >= base->model->n_counts[1])
+            goto done;
+        /* Advance unigram pointer if necessary in order to get one
+         * that points to this bigram. */
+        while (itor->bg - model->lm3g.bigrams >= itor->ug[1].bigrams) {
+            /* Stop if this is a successor iterator, since we don't
+             * want a new unigram. */
+            if (base->successor)
+                goto done;
+            ++itor->ug;
+            if (itor->ug == model->lm3g.unigrams + base->model->n_counts[0]) {
+                E_ERROR("Bigram %d has no valid unigram parent\n",
+                        itor->bg - model->lm3g.bigrams);
+                goto done;
+            }
+        }
+        break;
+    case 2:
+        ++itor->tg;
+        /* Check for end condition. */
+        if (itor->tg - model->lm3g.trigrams >= base->model->n_counts[2])
+            goto done;
+        /* Advance bigram pointer if necessary. */
+        while (itor->tg - model->lm3g.trigrams >=
+            FIRST_TG(model, (itor->bg - model->lm3g.bigrams + 1))) {
+            if (base->successor)
+                goto done;
+            ++itor->bg;
+            if (itor->bg == model->lm3g.bigrams + base->model->n_counts[1]) {
+                E_ERROR("Trigram %d has no valid bigram parent\n",
+                        itor->tg - model->lm3g.trigrams);
+
+               goto done;
+            }
+        }
+        /* Advance unigram pointer if necessary. */
+        while (itor->bg - model->lm3g.bigrams >= itor->ug[1].bigrams) {
+            ++itor->ug;
+            if (itor->ug == model->lm3g.unigrams + base->model->n_counts[0]) {
+                E_ERROR("Trigram %d has no valid unigram parent\n",
+                        itor->tg - model->lm3g.trigrams);
+                goto done;
+            }
+        }
+        break;
+    default: /* Should not happen. */
+        goto done;
+    }
+
+    return (ngram_iter_t *)itor;
+done:
+    ngram_iter_free(base);
+    return NULL;
+}
+
+static void
+lm3g_template_iter_free(ngram_iter_t *base)
+{
+    ckd_free(base);
+}