SphinxBase  5prealpha
sphinx_lm_eval.c
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41 #include <sphinxbase/logmath.h>
42 #include <sphinxbase/ngram_model.h>
43 #include <sphinxbase/cmd_ln.h>
44 #include <sphinxbase/ckd_alloc.h>
45 #include <sphinxbase/err.h>
46 #include <sphinxbase/pio.h>
47 #include <sphinxbase/strfuncs.h>
48 
49 #include <stdio.h>
50 #include <string.h>
51 #include <math.h>
52 
53 static const arg_t defn[] = {
54  { "-help",
56  "no",
57  "Shows the usage of the tool"},
58 
59  { "-logbase",
61  "1.0001",
62  "Base in which all log-likelihoods calculated" },
63 
64  { "-lm",
65  ARG_STRING,
66  NULL,
67  "Language model file"},
68 
69  { "-probdef",
70  ARG_STRING,
71  NULL,
72  "Probability definition file for classes in LM"},
73 
74  { "-lmctlfn",
75  ARG_STRING,
76  NULL,
77  "Control file listing a set of language models"},
78 
79  { "-lmname",
80  ARG_STRING,
81  NULL,
82  "Name of language model in -lmctlfn to use for all utterances" },
83 
84  { "-lsn",
85  ARG_STRING,
86  NULL,
87  "Transcription file to evaluate"},
88 
89  { "-text",
90  ARG_STRING,
91  "Text string to evaluate"},
92 
93  { "-mmap",
95  "no",
96  "Use memory-mapped I/O for reading binary LM files"},
97 
98  { "-lw",
100  "1.0",
101  "Language model weight" },
102 
103  { "-wip",
104  ARG_FLOAT32,
105  "1.0",
106  "Word insertion probability" },
107 
108  { "-verbose",
109  ARG_BOOLEAN,
110  "no",
111  "Print details of perplexity calculation" },
112 
113  /* FIXME: Support -lmstartsym, -lmendsym, -lmctlfn, -ctl_lm */
114  { NULL, 0, NULL, NULL }
115 };
116 
117 static int verbose;
118 
119 static int
120 calc_entropy(ngram_model_t *lm, char **words, int32 n,
121  int32 *out_n_ccs, int32 *out_n_oovs, int32 *out_lm_score)
122 {
123  int32 *wids;
124  int32 startwid;
125  int32 i, ch, nccs, noovs, unk;
126 
127  if (n == 0)
128  return 0;
129 
130  unk = ngram_unknown_wid(lm);
131 
132  /* Reverse this array into an array of word IDs. */
133  wids = ckd_calloc(n, sizeof(*wids));
134  for (i = 0; i < n; ++i)
135  wids[n-i-1] = ngram_wid(lm, words[i]);
136  /* Skip <s> as it's a context cue (HACK, this should be configurable). */
137  startwid = ngram_wid(lm, "<s>");
138 
139  /* Now evaluate the list of words in reverse using the
140  * remainder of the array as the history. */
141  ch = noovs = nccs = 0;
142  for (i = 0; i < n; ++i) {
143  int32 n_used;
144  int32 prob;
145 
146  /* Skip <s> as it's a context cue (HACK, this should be configurable). */
147  if (wids[i] == startwid) {
148  ++nccs;
149  continue;
150  }
151  /* Skip and count OOVs. */
152  if (wids[i] == NGRAM_INVALID_WID || wids[i] == unk) {
153  ++noovs;
154  continue;
155  }
156  /* Sum up information for each N-gram */
157  prob = ngram_ng_score(lm,
158  wids[i], wids + i + 1,
159  n - i - 1, &n_used);
160  if (verbose) {
161  int m;
162  printf("log P(%s|", ngram_word(lm, wids[i]));
163  m = i + ngram_model_get_size(lm) - 1;
164  if (m >= n)
165  m = n - 1;
166  while (m > i) {
167  printf("%s ", ngram_word(lm, wids[m--]));
168  }
169  printf(") = %d\n", prob);
170  }
171  ch -= prob;
172  }
173 
174  if (out_n_ccs) *out_n_ccs = nccs;
175  if (out_n_oovs) *out_n_oovs = noovs;
176 
177  /* Calculate cross-entropy CH = - 1/N sum log P(W|H) */
178  n -= (nccs + noovs);
179  if (n <= 0)
180  return 0;
181  if (out_lm_score)
182  *out_lm_score = -ch;
183  return ch / n;
184 }
185 
186 static void
187 evaluate_file(ngram_model_t *lm, logmath_t *lmath, const char *lsnfn)
188 {
189  FILE *fh;
190  lineiter_t *litor;
191  int32 nccs, noovs, nwords, lscr;
192  float64 ch, log_to_log2;;
193 
194  if ((fh = fopen(lsnfn, "r")) == NULL)
195  E_FATAL_SYSTEM("failed to open transcript file %s", lsnfn);
196 
197  /* We have to keep ch in floating-point to avoid overflows, so
198  * we might as well use log2. */
199  log_to_log2 = log(logmath_get_base(lmath)) / log(2);
200  lscr = nccs = noovs = nwords = 0;
201  ch = 0.0;
202  for (litor = lineiter_start(fh); litor; litor = lineiter_next(litor)) {
203  char **words;
204  int32 n, tmp_ch, tmp_noovs, tmp_nccs, tmp_lscr;
205 
206  n = str2words(litor->buf, NULL, 0);
207  if (n < 0)
208  E_FATAL("str2words(line, NULL, 0) = %d, should not happen\n", n);
209  if (n == 0) /* Do nothing! */
210  continue;
211  words = ckd_calloc(n, sizeof(*words));
212  str2words(litor->buf, words, n);
213 
214  /* Remove any utterance ID (FIXME: has to be a single "word") */
215  if (words[n-1][0] == '('
216  && words[n-1][strlen(words[n-1])-1] == ')')
217  n = n - 1;
218 
219  tmp_ch = calc_entropy(lm, words, n, &tmp_nccs,
220  &tmp_noovs, &tmp_lscr);
221 
222  ch += (float64) tmp_ch * (n - tmp_nccs - tmp_noovs) * log_to_log2;
223  nccs += tmp_nccs;
224  noovs += tmp_noovs;
225  lscr += tmp_lscr;
226  nwords += n;
227 
228  ckd_free(words);
229  }
230 
231  ch /= (nwords - nccs - noovs);
232  printf("cross-entropy: %f bits\n", ch);
233 
234  /* Calculate perplexity pplx = exp CH */
235  printf("perplexity: %f\n", pow(2.0, ch));
236  printf("lm score: %d\n", lscr);
237 
238  /* Report OOVs and CCs */
239  printf("%d words evaluated\n", nwords);
240  printf("%d OOVs (%.2f%%), %d context cues removed\n",
241  noovs, (double)noovs / nwords * 100, nccs);
242 }
243 
244 static void
245 evaluate_string(ngram_model_t *lm, logmath_t *lmath, const char *text)
246 {
247  char *textfoo;
248  char **words;
249  int32 n, ch, noovs, nccs, lscr;
250 
251  /* Split it into an array of strings. */
252  textfoo = ckd_salloc(text);
253  n = str2words(textfoo, NULL, 0);
254  if (n < 0)
255  E_FATAL("str2words(textfoo, NULL, 0) = %d, should not happen\n", n);
256  if (n == 0) /* Do nothing! */
257  return;
258  words = ckd_calloc(n, sizeof(*words));
259  str2words(textfoo, words, n);
260 
261  ch = calc_entropy(lm, words, n, &nccs, &noovs, &lscr);
262 
263  printf("input: %s\n", text);
264  printf("cross-entropy: %f bits\n",
265  ch * log(logmath_get_base(lmath)) / log(2));
266 
267  /* Calculate perplexity pplx = exp CH */
268  printf("perplexity: %f\n", logmath_exp(lmath, ch));
269  printf("lm score: %d\n", lscr);
270 
271  /* Report OOVs and CCs */
272  printf("%d words evaluated\n", n);
273  printf("%d OOVs, %d context cues removed\n",
274  noovs, nccs);
275 
276  ckd_free(textfoo);
277  ckd_free(words);
278 }
279 
280 int
281 main(int argc, char *argv[])
282 {
283  cmd_ln_t *config;
284  ngram_model_t *lm = NULL;
285  logmath_t *lmath;
286  const char *lmfn, *probdefn, *lsnfn, *text;
287 
288  if ((config = cmd_ln_parse_r(NULL, defn, argc, argv, TRUE)) == NULL)
289  return 1;
290 
291  verbose = cmd_ln_boolean_r(config, "-verbose");
292 
293  /* Create log math object. */
294  if ((lmath = logmath_init
295  (cmd_ln_float64_r(config, "-logbase"), 0, 0)) == NULL) {
296  E_FATAL("Failed to initialize log math\n");
297  }
298 
299  /* Load the language model. */
300  lmfn = cmd_ln_str_r(config, "-lm");
301  if (lmfn == NULL
302  || (lm = ngram_model_read(config, lmfn,
303  NGRAM_AUTO, lmath)) == NULL) {
304  E_FATAL("Failed to load language model from %s\n",
305  cmd_ln_str_r(config, "-lm"));
306  }
307  if ((probdefn = cmd_ln_str_r(config, "-probdef")) != NULL)
308  ngram_model_read_classdef(lm, probdefn);
310  cmd_ln_float32_r(config, "-lw"),
311  cmd_ln_float32_r(config, "-wip"));
312 
313  /* Now evaluate some text. */
314  lsnfn = cmd_ln_str_r(config, "-lsn");
315  text = cmd_ln_str_r(config, "-text");
316  if (lsnfn) {
317  evaluate_file(lm, lmath, lsnfn);
318  }
319  else if (text) {
320  evaluate_string(lm, lmath, text);
321  }
322 
323  return 0;
324 }
Command-line and other configurationparsing and handling.
SPHINXBASE_EXPORT ngram_model_t * ngram_model_read(cmd_ln_t *config, const char *file_name, ngram_file_type_t file_type, logmath_t *lmath)
Read an N-Gram model from a file on disk.
Definition: ngram_model.c:124
Miscellaneous useful string functions.
#define ckd_calloc(n, sz)
Macros to simplify the use of above functions.
Definition: ckd_alloc.h:248
SPHINXBASE_EXPORT int32 ngram_unknown_wid(ngram_model_t *model)
Get the unknown word ID for a language model.
Definition: ngram_model.c:550
Sphinx&#39;s memory allocation/deallocation routines.
SPHINXBASE_EXPORT int32 ngram_wid(ngram_model_t *model, const char *word)
Look up numerical word ID.
Definition: ngram_model.c:585
#define NGRAM_INVALID_WID
Impossible word ID.
Definition: ngram_model.h:83
SPHINXBASE_EXPORT cmd_ln_t * cmd_ln_parse_r(cmd_ln_t *inout_cmdln, arg_t const *defn, int32 argc, char *argv[], int32 strict)
Parse a list of strings into argumetns.
Definition: cmd_ln.c:556
#define ARG_STRING
String argument (optional).
Definition: cmd_ln.h:114
Line iterator for files.
Definition: pio.h:177
#define ckd_salloc(ptr)
Macro for ckd_salloc
Definition: ckd_alloc.h:264
SPHINXBASE_EXPORT char const * cmd_ln_str_r(cmd_ln_t *cmdln, char const *name)
Retrieve a string from a command-line object.
Definition: cmd_ln.c:949
SPHINXBASE_EXPORT void ckd_free(void *ptr)
Test and free a 1-D array.
Definition: ckd_alloc.c:244
SPHINXBASE_EXPORT logmath_t * logmath_init(float64 base, int shift, int use_table)
Initialize a log math computation table.
Definition: logmath.c:62
#define ARG_FLOAT32
Definition: cmd_ln.h:148
#define ARG_FLOAT64
Definition: cmd_ln.h:152
SPHINXBASE_EXPORT int ngram_model_apply_weights(ngram_model_t *model, float32 lw, float32 wip)
Apply a language weight, insertion penalty, and unigram weight to a language model.
Definition: ngram_model.c:360
N-Gram language models.
SPHINXBASE_EXPORT float64 logmath_get_base(logmath_t *lmath)
Get the log base.
Definition: logmath.c:368
SPHINXBASE_EXPORT lineiter_t * lineiter_next(lineiter_t *li)
Move to the next line in the file.
Definition: pio.c:347
SPHINXBASE_EXPORT lineiter_t * lineiter_start(FILE *fh)
Start reading lines from a file.
Definition: pio.c:264
SPHINXBASE_EXPORT int32 ngram_model_get_size(ngram_model_t *model)
Get the order of the N-gram model (i.e.
Definition: ngram_model.c:569
Implementation of logging routines.
#define E_FATAL_SYSTEM(...)
Print error text; Call perror(&quot;&quot;); exit(errno);.
Definition: err.h:90
#define ARG_BOOLEAN
Boolean (true/false) argument (optional).
Definition: cmd_ln.h:118
Argument definition structure.
SPHINXBASE_EXPORT int32 ngram_model_read_classdef(ngram_model_t *model, const char *file_name)
Read a class definition file and add classes to a language model.
Definition: ngram_model.c:1027
SPHINXBASE_EXPORT int32 str2words(char *line, char **wptr, int32 n_wptr)
Convert a line to an array of &quot;words&quot;, based on whitespace separators.
Definition: strfuncs.c:123
Opaque structure used to hold the results of command-line parsing.
#define cmd_ln_boolean_r(c, n)
Retrieve a boolean value from a command-line object.
Definition: cmd_ln.h:334
cmd_ln_t * config
Configuration parameters.
Definition: sphinx_fe.c:74
#define E_FATAL(...)
Exit with non-zero status after error message.
Definition: err.h:81
Common implementation of ngram_model_t.
SPHINXBASE_EXPORT const char * ngram_word(ngram_model_t *model, int32 wid)
Look up word string for numerical word ID.
Definition: ngram_model.c:596
Fast integer logarithmic addition operations.
SPHINXBASE_EXPORT float64 logmath_exp(logmath_t *lmath, int logb_p)
Convert integer log in base B to linear floating point.
Definition: logmath.c:456
Determine file type automatically.
Definition: ngram_model.h:78
SPHINXBASE_EXPORT int32 ngram_ng_score(ngram_model_t *model, int32 wid, int32 *history, int32 n_hist, int32 *n_used)
Quick general N-Gram score lookup.
Definition: ngram_model.c:375
file IO related operations.