compute-wer.py

import sys
import numpy
#bian bian 

def cmp_result(label, rec):
    dist_mat = numpy.zeros((len(label) + 1, len(rec) + 1), dtype='int32')
    dist_mat[0, :] = range(len(rec) + 1)
    dist_mat[:, 0] = range(len(label) + 1)
    for i in range(1, len(label) + 1):
        for j in range(1, len(rec) + 1):
            hit_score = dist_mat[i - 1, j - 1] + (label[i - 1] != rec[j - 1])
            ins_score = dist_mat[i, j - 1] + 1
            del_score = dist_mat[i - 1, j] + 1
            dist_mat[i, j] = min(hit_score, ins_score, del_score)

    dist = dist_mat[len(label), len(rec)]
    return dist, len(label)



def process(recfile, labelfile, resultfile, direction):
    total_dist = 0
    total_label = 0
    total_line = 0
    total_line_rec = 0
    total_line_error1  = 0
    total_line_error2 = 0 
    rec_mat = {}
    label_mat = {}
    result = {}
    with open(recfile) as f_rec:
        for line in f_rec:
            tmp = line.split()
            key = tmp[0]
            latex = tmp[1:]
            rec_mat[key] = latex
    with open(labelfile) as f_label:
        for line in f_label:
            tmp = line.split()
            key = tmp[0]
            if direction == 1:
                latex = tmp[1:]
            else:
                latex = tmp[1:][::-1]
            label_mat[key] = latex
    for key_rec in rec_mat:
        label = label_mat[key_rec]
        rec = rec_mat[key_rec]
        dist, llen = cmp_result(label, rec)
        total_dist += dist
        total_label += llen
        total_line += 1
        if dist == 0:
            total_line_rec += 1

        elif dist ==1:
            total_line_error1 +=1
        elif dist ==2:
            total_line_error2 +=1
        else:
            result[key_rec] = ''.join(label)+'\t'+''.join(rec)


    wer = float(total_dist) / total_label*100
    sacc = float(total_line_rec) / total_line *100
    sacc1 = float(total_line_rec+total_line_error1) /total_line *100
    sacc2 = float(total_line_rec+total_line_error1+total_line_error2) / total_line *100
    print('valid WER {:.4f},ExpRate {:.4f},{:.4f},{:.4f}'.format(wer,sacc,sacc1,sacc2))
    f_result = open(resultfile, 'w')
    f_result.write('WER {}\n'.format(wer/100))
    f_result.write('ExpRate {}\n'.format(sacc/100))
    f_result.close()

if __name__ == '__main__':
    if len(sys.argv) != 5:
        print('compute-wer.py recfile labelfile resultfile direction')
        sys.exit(0)
    process(sys.argv[1], sys.argv[2], sys.argv[3], int(sys.argv[4]))