"""WER print functions.
The functions here are used to print the computed statistics
with human-readable formatting.
They have a file argument, but you can also just use
contextlib.redirect_stdout, which may give a nicer syntax.
Authors
* Aku Rouhe 2020
"""
import sys
from speechbrain.utils import edit_distance
def print_wer_summary(wer_details, file=sys.stdout):
"""Prints out WER summary details in human-readable format.
This function essentially mirrors the Kaldi compute-wer output format.
Arguments
---------
wer_details : dict
Dict of wer summary details,
see ``speechbrain.utils.edit_distance.wer_summary``
for format.
file : stream
Where to write. (default: sys.stdout)
"""
print(
"%WER {WER:.2f} [ {num_edits} / {num_scored_tokens}, {insertions} ins, {deletions} del, {substitutions} sub ]".format( # noqa
**wer_details
),
file=file,
end="",
)
print(
(
" [PARTIAL]"
if wer_details["num_scored_sents"] < wer_details["num_ref_sents"]
else ""
),
file=file,
)
print(
"%SER {SER:.2f} [ {num_erroneous_sents} / {num_scored_sents} ]".format(
**wer_details
),
file=file,
)
print(
"Scored {num_scored_sents} sentences, {num_absent_sents} not present in hyp.".format( # noqa
**wer_details
),
file=file,
)
def print_alignments(
details_by_utterance,
file=sys.stdout,
empty_symbol="<eps>",
separator=" ; ",
print_header=True,
sample_separator=None,
):
"""Print WER summary and alignments.
Arguments
---------
details_by_utterance : list
List of wer details by utterance,
see ``speechbrain.utils.edit_distance.wer_details_by_utterance``
for format. Has to have alignments included.
file : stream
Where to write. (default: sys.stdout)
empty_symbol : str
Symbol to use when aligning to nothing.
separator : str
String that separates each token in the output. Note the spaces in the
default.
print_header: bool
Whether to print headers
sample_separator: str
A separator to put between samples (optional)
"""
if print_header:
_print_alignments_global_header(
file=file, empty_symbol=empty_symbol, separator=separator
)
for dets in details_by_utterance:
if dets["scored"]:
if print_header:
_print_alignment_header(dets, file=file)
_print_alignment(
dets["alignment"],
dets["ref_tokens"],
dets["hyp_tokens"],
file=file,
empty_symbol=empty_symbol,
separator=separator,
)
if sample_separator:
print(sample_separator, file=file)
# The following internal functions are used to
# print out more specific things
def _print_top_wer_utts(top_non_empty, top_empty, file=sys.stdout):
print("=" * 80, file=file)
print("UTTERANCES WITH HIGHEST WER", file=file)
if top_non_empty:
print(
"Non-empty hypotheses -- utterances for which output was produced:",
file=file,
)
for dets in top_non_empty:
print("{key} %WER {WER:.2f}".format(**dets), file=file)
else:
print("No utterances which had produced output!", file=file)
if top_empty:
print(
"Empty hypotheses -- utterances for which no output was produced:",
file=file,
)
for dets in top_empty:
print("{key} %WER {WER:.2f}".format(**dets), file=file)
else:
print("No utterances which had not produced output!", file=file)
def _print_top_wer_spks(spks_by_wer, file=sys.stdout):
print("=" * 80, file=file)
print("SPEAKERS WITH HIGHEST WER", file=file)
for dets in spks_by_wer:
print("{speaker} %WER {WER:.2f}".format(**dets), file=file)
def _print_alignment(
alignment, a, b, empty_symbol="<eps>", separator=" ; ", file=sys.stdout
):
# First, get equal length text for all:
a_padded = []
b_padded = []
ops_padded = []
for op, i, j in alignment: # i indexes a, j indexes b
op_string = str(op)
a_string = str(a[i]) if i is not None else empty_symbol
b_string = str(b[j]) if j is not None else empty_symbol
# NOTE: the padding does not actually compute printed length,
# but hopefully we can assume that printed length is
# at most the str len
pad_length = max(len(op_string), len(a_string), len(b_string))
a_padded.append(a_string.center(pad_length))
b_padded.append(b_string.center(pad_length))
ops_padded.append(op_string.center(pad_length))
# Then print, in the order Ref, op, Hyp
print(separator.join(a_padded), file=file)
print(separator.join(ops_padded), file=file)
print(separator.join(b_padded), file=file)
def _print_alignments_global_header(
empty_symbol="<eps>", separator=" ; ", file=sys.stdout
):
print("=" * 80, file=file)
print("ALIGNMENTS", file=file)
print("", file=file)
print("Format:", file=file)
print("<utterance-id>, WER DETAILS", file=file)
# Print the format with the actual
# print_alignment function, using artificial data:
a = ["reference", "on", "the", "first", "line"]
b = ["and", "hypothesis", "on", "the", "third"]
alignment = [
(edit_distance.EDIT_SYMBOLS["ins"], None, 0),
(edit_distance.EDIT_SYMBOLS["sub"], 0, 1),
(edit_distance.EDIT_SYMBOLS["eq"], 1, 2),
(edit_distance.EDIT_SYMBOLS["eq"], 2, 3),
(edit_distance.EDIT_SYMBOLS["sub"], 3, 4),
(edit_distance.EDIT_SYMBOLS["del"], 4, None),
]
_print_alignment(
alignment,
a,
b,
file=file,
empty_symbol=empty_symbol,
separator=separator,
)
def _print_alignment_header(wer_details, file=sys.stdout):
print("=" * 80, file=file)
print(
"{key}, %WER {WER:.2f} [ {num_edits} / {num_ref_tokens}, {insertions} ins, {deletions} del, {substitutions} sub ]".format( # noqa
**wer_details
),
file=file,
)