Python pgm解析和格式转换 - maohaihua/ros_study GitHub Wiki

https://blog.csdn.net/u012005313/article/details/83685584

from future import print_function

import cv2 import time import os import operator import numpy as np import argparse from PIL import Image

author = 'zj'

image_formats = ['jpg', 'JPG', 'jpeg', 'JPEG', 'png', 'PNG']

def is_pgm_file(in_path): if not os.path.isfile(in_path): return False if in_path is not str and not in_path.endswith('.pgm'): return False return True

def convert_pgm_by_PIL(in_path, out_path): if not is_pgm_file(in_path): raise Exception("%s 不是一个PGM文件" % in_path) # 读取文件 im = Image.open(in_path) im.save(out_path)

def convert_pgm_P5(in_path, out_path): """ 将pgm文件转换成其它图像格式 读取二进制文件，先读取幻数，再读取宽和高，以及最大值 :param in_path: 输入pgm文件路径 :param out_path: 输出文件路径 """ if not is_pgm_file(in_path): raise Exception("%s 不是一个PGM文件" % in_path) with open(in_path, 'rb') as f: # 读取两个字节 - 幻数，并解码成字符串 magic_number = f.readline().strip().decode('utf-8') if not operator.eq(magic_number, "P5"): raise Exception("该图像有误") # 读取高和宽 width, height = f.readline().strip().decode('utf-8').split(' ') width = int(width) height = int(height) # 读取最大值 maxval = f.readline().strip() # 每次读取灰度值的字节数 if int(maxval) < 256: one_reading = 1 else: one_reading = 2 # 创建空白图像，大小为(行，列)=(height, width) img = np.zeros((height, width)) img[:, :] = [[ord(f.read(one_reading)) for j in range(width)] for i in range(height)] cv2.imwrite(out_path, img) print('%s save ok' % out_path)

def convert_pgm_P5_batch(in_dir, out_dir, res_format): """ 批量转换PGM文件 :param in_dir: pgm文件夹路径 :param out_dir: 输出文件夹路径 :param res_format: 结果图像格式 """ if not os.path.isdir(in_dir): raise Exception('%s 不是路径' % in_dir) if not os.path.isdir(out_dir): raise Exception('%s 不是路径' % out_dir) if not res_format in image_formats: raise Exception('%s 暂不支持' % res_format) file_list = os.listdir(in_dir) for file_name in file_list: file_path = os.path.join(in_dir, file_name) # 若为pgm文件路径，那么将其进行格式转换 if is_pgm_file(file_path): file_out_path = os.path.join(out_dir, os.path.splitext(file_name)[0] + '.' + res_format) convert_pgm_P5(file_path, file_out_path) # 若为目录，则新建结果文件目录，递归处理 elif os.path.isdir(file_path): file_out_dir = os.path.join(out_dir, file_name) if not os.path.exists(file_out_dir): os.mkdir(file_out_dir) convert_pgm_P5_batch(file_path, file_out_dir, res_format) else: pass print('batch operation over')

if name == 'main': script_start_time = time.time()

parser = argparse.ArgumentParser(description='Format Converter - PGM')

### Positional arguments

### Optional arguments

parser.add_argument('-i', '--input', type=str, help='Path to the pgm file')
parser.add_argument('-o', '--output', type=str, help='Path to the result file')
parser.add_argument('--input_dir', type=str, help='Dir to the pgm files')
parser.add_argument('--output_dir', type=str, help='Dir to the result files')
parser.add_argument('-f', '--format', default='png', type=str, help='result image format')
parser.add_argument('-b', '--batch', action="store_true", default=False, help='Batch processing')

args = vars(parser.parse_args())
# print(args)
in_path = args['input']
out_path = args['output']

isbatch = args['batch']
in_dir = args['input_dir']
out_dir = args['output_dir']
res_format = args['format']

if in_path is not None and out_path is not None:
    # 转换单个pgm文件格式
    convert_pgm_P5(in_path, out_path)
    # convert_pgm_by_PIL(in_path, out_path)
elif isbatch:
    # 批量转换
    convert_pgm_P5_batch(in_dir, out_dir, res_format)
else:
    print('请输入相应参数')

print('Script took %s seconds.' % (time.time() - script_start_time,))