Annotations convertion to PASCAL VOC XML format

annotations.py

import os
import json
from pprint import pprint

def save_image_set_txt(path, index):
    f = open(path, 'w')
    for ind in index:
        f.write(ind+'\n')
    f.close()

converted_annotations = '../notebooks/annotations/'
train_img_names = []

with open('../../Downloads/rectangles.json') as data_file:    
    data = json.load(data_file)

for i in range(len(data)):
    # get INDEX name for annotations (image filename without extension)
    INDEX = data[i]['filename'][17:-4]
    train_img_names.append(INDEX)
    
    # add basic annotations info     
    f = open(converted_annotations + INDEX + '.xml','w')
    line = "<annotation>" + '\n'
    f.write(line)
    line = '\t\t<folder>' + "folder" + '</folder>' + '\n'
    f.write(line)
    line = '\t\t<filename>' +  INDEX + '</filename>' + '\n'
    f.write(line)
    line = '\t\t<source>\n\t\t<database>Source</database>\n\t</source>\n'
    f.write(line)
#     TODO: add proper image sizes
#     (width, height) = image.shape[0], image.shape[1]
    (width, height) = 500, 500
    line = '\t<size>\n\t\t<width>'+ str(width) + '</width>\n\t\t<height>' + str(height) + '</height>\n\t'
    line += '\t<depth>3</depth>\n\t</size>'
    f.write(line)
    line = '\n\t<segmented>Unspecified</segmented>'
    f.write(line)
    
    for annotation in data[i]['annotations']:          
        x=int(annotation['x'])
        y=int(annotation['y'])
        w=int(annotation['width'])
        h=int(annotation['height'])
        line = '\n\t<object>'
        line += '\n\t\t<name>'+annotation['class']+'</name>\n\t\t<pose>Unspecified</pose>'
        line += '\n\t\t<truncated>Unspecified</truncated>\n\t\t<difficult>0</difficult>'
        line += '\n\t\t<bndbox>\n\t\t\t<xmin>' + str(x) + '</xmin>'            
        line += '\n\t\t\t<ymin>' + str(y) + '</ymin>'
        line += '\n\t\t\t<xmax>' + str(x+w) + '</xmax>'
        line += '\n\t\t\t<ymax>' + str(y+h) + '</ymax>'
        line += '\n\t\t</bndbox>'
        line += '\n\t</object>\n' 
        f.write(line) 
        
    line = "</annotation>" + '\n'
    f.write(line)
    f.close()
    
save_image_set_txt('train.txt', train_img_names)