Source code for bob.bio.base.script.gen

"""Generate random scores.
"""
import os
import logging
import numpy
import click
from bob.extension.scripts.click_helper import verbosity_option
from bob.io.base import create_directories_safe
from bob.measure.script import common_options

logger = logging.getLogger(__name__)


[docs]def gen_score_distr( mean_neg, mean_pos, sigma_neg=10, sigma_pos=10, n_neg=5000, n_pos=5000, seed=0 ): """Generate scores from normal distributions Parameters ---------- mean_neg : float Mean for negative scores mean_pos : float Mean for positive scores sigma_neg : float STDev for negative scores sigma_pos : float STDev for positive scores n_pos: int The number of positive scores generated n_neg: int The number of negative scores generated seed: int A value to initialize the Random Number generator. Giving the same value (or not specifying 'seed') on two different calls will generate the same lists of scores. Returns ------- neg_scores : :any:`list` Negatives scores pos_scores : :any:`list` Positive scores """ logger.debug("Initializing RNG.") numpy.random.seed(seed) logger.info(f"Generating {n_neg} negative and {n_pos} positive scores.") neg_scores = numpy.random.normal(loc=mean_neg, scale=sigma_neg, size=n_neg) pos_scores = numpy.random.normal(loc=mean_pos, scale=sigma_pos, size=n_pos) return neg_scores, pos_scores
[docs]def write_scores_to_file( neg, pos, filename, n_subjects=5, n_probes_per_subject=5, n_unknown_subjects=0, neg_unknown=None, five_col=False, ): """ Writes score distributions Parameters ---------- neg : :py:class:`numpy.ndarray` Scores for negative samples. pos : :py:class:`numpy.ndarray` Scores for positive samples. filename : str The path to write the score to. n_subjects: int Number of different subjects n_probes_per_subject: int Number of different samples used as probe for each subject n_unknown_subjects: int The number of unknown (no registered model) subjects neg_unknown: None or list The of unknown subjects scores five_col : bool If 5-colum format, else 4-column """ logger.debug(f"Creating result directories ('{filename}').") create_directories_safe(os.path.dirname(filename)) s_subjects = ["x%d" % i for i in range(n_subjects)] logger.debug("Writing scores to files.") with open(filename, "wt") as f: # Generate one line per probe (unless "--force-count" specified) logger.debug("Writing positive scores.") for i, score in enumerate(pos): s_name = s_subjects[int(i / n_probes_per_subject) % n_subjects] s_five = " " if not five_col else " d" + s_name + " " probe_id = "%s_%d" % (s_name, i % n_probes_per_subject) f.write("%s%s%s %s %f\n" % (s_name, s_five, s_name, probe_id, score)) # Generate one line per probe against each ref (unless "--force-count" specified) logger.debug("Writing negative scores.") for i, score in enumerate(neg): n_impostors = n_subjects - 1 ref = s_subjects[int(i / n_probes_per_subject / n_impostors) % n_subjects] impostors = [s for s in s_subjects if s != ref] # ignore pos probe = impostors[int(i / n_probes_per_subject) % n_impostors] s_five = " " if not five_col else " d" + ref probe_id = "%s_%d" % (probe, i % n_probes_per_subject) f.write("%s%s%s %s %f\n" % (ref, s_five, probe, probe_id, score)) logger.debug("Writing unknown scores.") if neg_unknown is not None: s_unknown_subjects = ["u%d" % i for i in range(n_unknown_subjects)] for i, score in enumerate(neg_unknown): ref = s_subjects[ int(i / n_probes_per_subject / n_unknown_subjects) % n_subjects ] probe = s_unknown_subjects[ int(i / n_probes_per_subject) % n_unknown_subjects ] s_five = " " if not five_col else " d" + ref + " " probe_id = "%s_%d" % (probe, i % n_probes_per_subject) f.write("%s%s%s %s %f\n" % (ref, s_five, probe, probe_id, score))
@click.command( epilog=""" Scores generation examples: Output 'scores-dev' and 'scores-eval' in a new folder 'generated_scores/': $ bob bio gen ./generated_scores Output scores similar to a system evaluated on the AT&T dataset dev group: $ bob bio gen -s 20 -p 5 ./generated_scores Output a given number of scores in each file: $ bob bio gen -f --n-neg 500 --n-pos 100 ./generated_scores Include unknown subjects scores: $ bob bio gen -s 5 -u 2 ./generated_scores Change the mean and standard deviation of the scores distributions: $ bob bio gen -mm 1 -sp 0.3 -mnm -1 -sn 0.5 ./generated_scores You can observe the distributions histograms in a pdf file with: $ bob bio hist -e ./generated_scores/scores-{dev,eval} -o hist_gen.pdf """ ) @click.argument("outdir") @click.option( "-mm", "--mean-match", default=10, type=click.FLOAT, show_default=True, help="Mean for the positive scores distribution", ) @click.option( "-mnm", "--mean-non-match", default=-10, type=click.FLOAT, show_default=True, help="Mean for the negative scores distribution", ) @click.option( "-p", "--n-probes-per-subject", default=5, type=click.INT, show_default=True, help="Number of probes per subject", ) @click.option( "-s", "--n-subjects", default=50, type=click.INT, show_default=True, help="Number of subjects", ) @click.option( "-sp", "--sigma-positive", default=10, type=click.FLOAT, show_default=True, help="Variance for the positive score distributions", ) @click.option( "-sn", "--sigma-negative", default=10, type=click.FLOAT, show_default=True, help="Variance for the negative score distributions", ) @click.option( "-u", "--n-unknown-subjects", default=0, type=click.INT, show_default=True, help="Number of unknown subjects (useful for openset plots)", ) @click.option( "-f", "--force-count", "force_count", is_flag=True, help="Use --n-pos and --n-neg amounts instead of the subject and sample counts", ) @click.option( "--n-pos", "n_pos", default=5000, type=click.INT, show_default=True, help="Number of Positive verifications (number of lines in the file)", ) @click.option( "--n-neg", "n_neg", default=5000, type=click.INT, show_default=True, help="Number of Negative verifications (number of lines in the file)", ) @click.option( "--n-unk", "n_unk", default=5000, type=click.INT, show_default=True, help="Number of Unknown verifications (number of lines in the file)", ) @click.option("--five-col/--four-col", default=False, show_default=True) @verbosity_option() def gen( outdir, mean_match, mean_non_match, n_probes_per_subject, n_subjects, sigma_positive, sigma_negative, n_unknown_subjects, five_col, force_count, n_pos, n_neg, n_unk, **kwargs, ): """Generate random scores. Generates random scores in 4col or 5col format. The scores are generated using Gaussian distribution whose mean and variance are an input parameter. The generated scores can be used as hypothetical datasets. This command generates scores relative to the number of subjects and probes per subjects, unless the -f flag is set. In that case, the --n-pos and --n-neg options are used as number of genuine and impostor comparisons. """ # Compute the number of verifications needed if force_count: neg_count, pos_count, unknown_count = n_neg, n_pos, n_unk else: # One reference (model), and `n_probes_per_subject` probes per subject neg_count = n_subjects * n_probes_per_subject * (n_subjects - 1) pos_count = n_probes_per_subject * n_subjects unknown_count = n_unknown_subjects * n_subjects * n_probes_per_subject # Generate the data logger.info("Generating dev scores.") neg_dev, pos_dev = gen_score_distr( mean_non_match, mean_match, sigma_negative, sigma_positive, n_neg=neg_count, n_pos=pos_count, seed=0, ) logger.info("Generating eval scores.") neg_eval, pos_eval = gen_score_distr( mean_non_match, mean_match, sigma_negative, sigma_positive, n_neg=neg_count, n_pos=pos_count, seed=1, ) # For simplicity I will use the same distribution for dev-eval if n_unknown_subjects: logger.info("Generating unknown scores.") neg_unknown, _ = gen_score_distr( mean_non_match, mean_match, sigma_negative, sigma_positive, n_neg=unknown_count, n_pos=0, seed=2, ) else: neg_unknown = None # Write the data into files logger.info("Saving results.") write_scores_to_file( neg_dev, pos_dev, os.path.join(outdir, "scores-dev"), n_subjects, n_probes_per_subject, n_unknown_subjects, neg_unknown, five_col, ) write_scores_to_file( neg_eval, pos_eval, os.path.join(outdir, "scores-eval"), n_subjects, n_probes_per_subject, n_unknown_subjects, neg_unknown, five_col, )