Make seg_iter and hyp behave as expected in kws search (fixes #122)

cython/test/config_test.py

@@ -124,6 +124,7 @@ def test_config__iter(self):
         self.assertEqual(default_len, len(config))
         config["hmm"] = os.path.join(MODELDIR, "en-us", "en-us")
         config["fsg"] = os.path.join(DATADIR, "goforward.fsg")
+        config["lm"] = None  # It won't do this automatically
         config["dict"] = os.path.join(DATADIR, "turtle.dic")
         self.assertEqual(default_len, len(config))
         for key in config:

cython/test/kws_test.py

@@ -13,15 +13,15 @@ def test_kws(self):
         stream = open(os.path.join(DATADIR, "goforward.raw"), "rb")
 
         # Process audio chunk by chunk. On keyphrase detected perform action and restart search
-        decoder = Decoder(keyphrase="forward",
+        decoder = Decoder(kws=os.path.join(DATADIR, "goforward.kws"),
                           loglevel="INFO",
-                          lm=None,
-                          kws_threshold=1e20)
+                          lm=None)
         decoder.start_utt()
-        while True:
+        keywords = ["forward", "meters"]
+        while keywords:
             buf = stream.read(1024)
             if buf:
-                decoder.process_raw(buf, False, False)
+                decoder.process_raw(buf)
             else:
                 break
             if decoder.hyp() != None:
@@ -34,10 +34,26 @@ def test_kws(self):
                 print("Detected keyphrase, restarting search")
                 for seg in decoder.seg():
                     self.assertTrue(seg.end_frame > seg.start_frame)
-                    self.assertEqual(seg.word, "forward")
+                    self.assertEqual(seg.word, keywords.pop(0))
                 decoder.end_utt()
                 decoder.start_utt()
         stream.close()
+        decoder.end_utt()
+
+        # Detect keywords in a batch utt, make sure they show up in the right order
+        stream = open(os.path.join(DATADIR, "goforward.raw"), "rb")
+        decoder.start_utt()
+        decoder.process_raw(stream.read(), full_utt=True)
+        decoder.end_utt()
+        print(
+            [
+                (seg.word, seg.prob, seg.start_frame, seg.end_frame)
+                for seg in decoder.seg()
+            ]
+        )
+        self.assertEqual(decoder.hyp().hypstr, "forward meters")
+        self.assertEqual(["forward", "meters"],
+                         [seg.word for seg in decoder.seg()])
 
 
 if __name__ == "__main__":

src/kws_detections.c

@@ -102,6 +102,7 @@ kws_detections_hyp_str(kws_detections_t *detections, int frame, int delay)
 
     hyp_str = (char *)ckd_calloc(len, sizeof(char));
     c = hyp_str;
+    detections->detect_list = glist_reverse(detections->detect_list);
     for (gn = detections->detect_list; gn; gn = gnode_next(gn)) {
 	kws_detection_t *det = (kws_detection_t *)gnode_ptr(gn);
 	if (det->ef < frame - delay) {
@@ -115,6 +116,7 @@ kws_detections_hyp_str(kws_detections_t *detections, int frame, int delay)
         c--;
 	*c = '\0';
     }
+    detections->detect_list = glist_reverse(detections->detect_list);
     return hyp_str;
 }
 

src/kws_search.c

@@ -76,13 +76,14 @@ static void
 kws_seg_free(ps_seg_t *seg)
 {
     kws_seg_t *itor = (kws_seg_t *)seg;
+    ckd_free(itor->detections);
     ckd_free(itor);
 }
 
 static void
 kws_seg_fill(kws_seg_t *itor)
 {
-    kws_detection_t* detection = (kws_detection_t*)gnode_ptr(itor->detection);
+    kws_detection_t* detection = itor->detections[itor->pos];
 
     itor->base.text = detection->keyphrase;
     itor->base.wid = BAD_S3WID;
@@ -98,12 +99,7 @@ kws_seg_next(ps_seg_t *seg)
 {
     kws_seg_t *itor = (kws_seg_t *)seg;
 
-    gnode_t *detect_head = gnode_next(itor->detection);
-    while (detect_head != NULL && ((kws_detection_t*)gnode_ptr(detect_head))->ef > itor->last_frame)
-         detect_head = gnode_next(detect_head);
-    itor->detection = detect_head;
-
-    if (!itor->detection) {
+    if (++itor->pos == itor->n_detections) {
         kws_seg_free(seg);
         return NULL;
     }
@@ -124,18 +120,31 @@ kws_search_seg_iter(ps_search_t * search)
     kws_search_t *kwss = (kws_search_t *)search;
     kws_seg_t *itor;
     gnode_t *detect_head = kwss->detections->detect_list;
+    gnode_t *gn;
 
     while (detect_head != NULL && ((kws_detection_t*)gnode_ptr(detect_head))->ef > kwss->frame - kwss->delay)
 	detect_head = gnode_next(detect_head);
 
     if (!detect_head)
         return NULL;
 
-    itor = (kws_seg_t *)ckd_calloc(1, sizeof(*itor));
+    /* Count and reverse them into the vector. */
+    itor = ckd_calloc(1, sizeof(*itor));
+    for (gn = detect_head; gn; gn = gnode_next(gn))
+        itor->n_detections++;
+    itor->detections = ckd_calloc(itor->n_detections, sizeof(*itor->detections));
+    itor->pos = itor->n_detections - 1;
+    for (gn = detect_head; gn; gn = gnode_next(gn))
+        itor->detections[itor->pos--] = (kws_detection_t *)gnode_ptr(gn);
+    itor->pos = 0;
+
+    /* Copy the detections here to get them in the right order and
+     * avoid undefined behaviour if recognition continues during
+     * iteration. */
+
     itor->base.vt = &kws_segfuncs;
     itor->base.search = search;
     itor->base.lwf = 1.0;
-    itor->detection = detect_head;
     itor->last_frame = kwss->frame - kwss->delay;
     kws_seg_fill(itor);
     return (ps_seg_t *)itor;

src/kws_search.h

@@ -57,9 +57,11 @@ extern "C" {
  * Segmentation "iterator" for KWS history.
  */
 typedef struct kws_seg_s {
-    ps_seg_t base;       /**< Base structure. */
-    gnode_t *detection;  /**< Keyphrase detection correspondent to segment. */
-    frame_idx_t last_frame; /**< Last frame to raise the detection */
+    ps_seg_t base;                /**< Base structure. */
+    kws_detection_t **detections; /**< Vector of current detections. */
+    frame_idx_t last_frame;       /**< Last frame to raise the detection. */
+    int n_detections;             /**< Size of vector. */
+    int pos;                      /**< Position of iterator. */
 } kws_seg_t;
 
 typedef struct kws_keyphrase_s {

test/data/goforward.kws

@@ -3,6 +3,7 @@ something
 bad line / here
 just bad line /
 forward
+meters
 
 non_existign_word
 

test/unit/test_keyphrase.c

@@ -19,5 +19,5 @@ main(int argc, char *argv[])
                     "hmm: \"" MODELDIR "/en-us/en-us\","
                     "kws: \"" DATADIR "/goforward.kws\","
                     "dict: \"" MODELDIR "/en-us/cmudict-en-us.dict\""));
-    return ps_decoder_test(config, "KEYPHRASE", "forward");
+    return ps_decoder_test(config, "KEYPHRASE", "forward meters");
 }