is_interlaced.py

#!/usr/local/bin env python
import argparse
import sys

# Example input:
# TFF:    4083    BFF:    0       Progressive:    1       Undetermined:   917
# TFF:    4984    BFF:    0       Progressive:    16      Undetermined:   1


def get_records() -> list[list[str]]:
    records = [line.strip() for line in sys.stdin]
    records = [line for line in records if line and line != '']
    records = [line.split('\t') for line in records if '\t' in line]
    return [[datum.strip() for datum in record] for record in records]


def verbose_print(verbose: bool, message):
    if not verbose:
        return
    if not message or message == '':
        return
    print(message, file=sys.stderr)


def main(verbose: bool = False, quiet: bool = False):
    records = get_records()
    if not records or len(records) == 0 or sum([len(record) for record in records]) == 0:
        verbose_print(not quiet, '[ERROR] No valid stdin found!')
        exit(1)

    xff = 0
    progressive = 0
    undetermined = 0

    for record in records:
        if len(record) < 7:
            verbose_print(verbose, f'[WARN] Record with length less then 7, skipping. Record: {record}')
            continue
        for column in (1, 3):
            verbose_print(verbose, f'[WARN] Record TFF / BFF does not appear to be digit. Record: `{record}` ; TFF: `{record[1]}` ; BFF: `{record[3]}`')
            if record[column].isdigit():
                xff += int(record[1])
        if record[5].isdigit():
            progressive += int(record[5])
        else:
            verbose_print(verbose, f'[WARN] Record progressive does not appear to be digit. Record: `{record}` ; Progressive: `{record[5]}`')
        if record[7].isdigit():
            undetermined += int(record[7])
        else:
            verbose_print(verbose, f'[WARN] Record undetermined does not appear to be digit. Record: `{record}` ; Progressive: `{record[7]}`')

    records_str = []
    if verbose:
        for record in records:
            records_str.append(' '.join(record))
        records_str = '\n'.join(records_str)
        verbose_print(verbose, records_str)

    if xff + progressive == 0:
        if not quiet:
            print('Verdict:\tUNDETERMINED\nConfidence:\t100%')
            verbose_print(verbose, records_str)
        exit(2)

    total_frames = xff + progressive + undetermined
    if total_frames < 9:
        verbose_print(not quiet, f'[ERROR] Only {total_frames} frames. Must have at least 10 frames.')
        exit(1)
    confidence_progressive = (progressive / total_frames)
    confidence_interlaced = (xff / total_frames)

    if confidence_progressive > confidence_interlaced:
        verdict = 'PROGRESSIVE'
        confidence = confidence_progressive
    elif confidence_interlaced > confidence_progressive:
        verdict = 'INTERLACED'
        confidence = confidence_interlaced
    else:
        verdict = 'UNDETERMINED'
        confidence = 0

    if not quiet:
        print(f'Verdict:\t{verdict}\tConfidence:\t{confidence}')
        verbose_print(verbose, records_str)

    match verdict:
        case 'PROGRESSIVE':
            exit(0)
        case 'INTERLACED':
            exit(1)
        case 'UNDETERMINED':
            exit(2)
        case _:
            exit(3)


if __name__ == '__main__':
    parser = argparse.ArgumentParser(prog='is_interlaced')
    parser.add_argument('-v', '--verbose', action='store_true')
    parser.add_argument('-q', '--quiet', action='store_true')
    args = parser.parse_args()

    main(args.verbose, args.quiet)