从零开始使用Detectron训练第三方数据集是什么体验（三）

电玩女神 2022-03-20 15:56 185阅读 0赞

**从零开始使用Detectron训练第三方数据集是什么体验（三）**

> **本栏目分为6个部分：**
> 
>  *  [第1部分：Detectron框架简介与安装][1_Detectron]
>  *  [第2部分（本文）：使用LabelImgPlus对图片进行标注][2_LabelImgPlus]
>  *  第3部分（本文）：数据集处理
>  *  [第4部分：在detectron上部署数据集][4_detectron]
>  *  [第5部分：训练][5]
>  *  [第6部分：测试][6]  
>     GitHub： [https://github.com/zhiweichen95/detectron\_my][https_github.com_zhiweichen95_detectron_my]

**第3部分：数据集处理**

### 文章目录 ###

*  0 前言
 *   *  0.1 准备工作
 *  1 xml转json
 *  2 制作txt文件

# 0 前言 #

本节将对上一节使用LabelImgPlus工具标注好的数据需要进一步处理。对于Detectron框架来说，本人采用了VOC数据集的格式与树形结构存放图片数据。具体为何要这样处理，在下一节的“在detectron上部署数据集”将会详细说明。  
  本节将对上一节使用LabelImgPlus工具标注好的数据需要进一步处理。对于Detectron框架来说，本人采用了VOC数据集的格式与树形结构存放图片数据。

## 0.1 准备工作 ##

将训练图片放在同一个文件夹中，将测试图片放在同一个文件夹中。

# 1 xml转json #

xml2json.py文件如下：

# coding=utf-8
    import xml.etree.ElementTree as ET
    import os
    import json
    import collections
    
    coco = dict()
    coco['images'] = []
    coco['type'] = 'instances'
    coco['annotations'] = []
    coco['categories'] = []
    
    #category_set = dict()
    image_set = set()
    image_id = 2019100001  # train:2018xxx; val:2019xxx; test:2020xxx
    category_item_id = 1
    annotation_id = 1
    category_set = ['people', 'bicycle', 'electric bicycle'] #这里填写好检测的类别
    '''
    def addCatItem(name):
        global category_item_id
        category_item = dict()
        category_item['supercategory'] = 'none'
        category_item_id += 1
        category_item['id'] = category_item_id
        category_item['name'] = name
        coco['categories'].append(category_item)
        category_set[name] = category_item_id
        return category_item_id
    '''
    
    
    def addCatItem(name):
        '''
        增加json格式中的categories部分
        '''
        global category_item_id
        category_item = collections.OrderedDict()
        category_item['supercategory'] = 'none'
        category_item['id'] = category_item_id
        category_item['name'] = name
        coco['categories'].append(category_item)
        category_item_id += 1
    
    
    def addImgItem(file_name, size):
        global image_id
        if file_name is None:
            raise Exception('Could not find filename tag in xml file.')
        if size['width'] is None:
            raise Exception('Could not find width tag in xml file.')
        if size['height'] is None:
            raise Exception('Could not find height tag in xml file.')
        # image_item = dict()    #按照一定的顺序，这里采用collections.OrderedDict()
        image_item = collections.OrderedDict()
        jpg_name = os.path.splitext(file_name)[0] + '.png'
        image_item['file_name'] = jpg_name
        image_item['width'] = size['width']
        image_item['height'] = size['height']
        image_item['id'] = image_id
        coco['images'].append(image_item)
        image_set.add(jpg_name)
        image_id = image_id + 1
        return image_id
    
    
    def addAnnoItem(object_name, image_id, category_id, bbox):
        global annotation_id
        #annotation_item = dict()
        annotation_item = collections.OrderedDict()
        annotation_item['segmentation'] = []
        seg = []
        # bbox[] is x,y,w,h
        # left_top
        seg.append(bbox[0])
        seg.append(bbox[1])
        # left_bottom
        seg.append(bbox[0])
        seg.append(bbox[1] + bbox[3])
        # right_bottom
        seg.append(bbox[0] + bbox[2])
        seg.append(bbox[1] + bbox[3])
        # right_top
        seg.append(bbox[0] + bbox[2])
        seg.append(bbox[1])
        annotation_item['segmentation'].append(seg)
        annotation_item['area'] = bbox[2] * bbox[3]
        annotation_item['iscrowd'] = 0
        annotation_item['image_id'] = image_id
        annotation_item['bbox'] = bbox
        annotation_item['category_id'] = category_id
        annotation_item['id'] = annotation_id
        annotation_item['ignore'] = 0
        annotation_id += 1
        coco['annotations'].append(annotation_item)
    
    
    def parseXmlFiles(xml_path):
        xmllist = os.listdir(xml_path)
        xmllist.sort()
        for f in xmllist:
            if not f.endswith('.xml'):
                continue
    
            bndbox = dict()
            size = dict()
            current_image_id = None
            current_category_id = None
            file_name = None
            size['width'] = None
            size['height'] = None
            size['depth'] = None
    
            xml_file = os.path.join(xml_path, f)
            print(xml_file)
    
            tree = ET.parse(xml_file)
            root = tree.getroot()  # 抓根结点元素
    
            if root.tag != 'annotation':  # 根节点标签
                raise Exception(
                    'pascal voc xml root element should be annotation, rather than {}'.format(root.tag))
    
            # elem is <folder>, <filename>, <size>, <object>
            for elem in root:
                current_parent = elem.tag
                current_sub = None
                object_name = None
    
                # elem.tag, elem.attrib，elem.text
                if elem.tag == 'folder':
                    continue
    
                if elem.tag == 'filename':
                    file_name = elem.text
                    if file_name in category_set:
                        raise Exception('file_name duplicated')
    
                # add img item only after parse <size> tag
                elif current_image_id is None and file_name is not None and size['width'] is not None:
                    if file_name not in image_set:
                        current_image_id = addImgItem(file_name, size)  # 图片信息
                        print('add image with {} and {}'.format(file_name, size))
                    else:
                        raise Exception('duplicated image: {}'.format(file_name))
                        # subelem is <width>, <height>, <depth>, <name>, <bndbox>
                for subelem in elem:
                    bndbox['xmin'] = None
                    bndbox['xmax'] = None
                    bndbox['ymin'] = None
                    bndbox['ymax'] = None
    
                    current_sub = subelem.tag
                    if current_parent == 'object' and subelem.tag == 'name':
                        object_name = subelem.text
                        # if object_name not in category_set:
                        #    current_category_id = addCatItem(object_name)
                        # else:
                        #current_category_id = category_set[object_name]
                        current_category_id = category_set.index(
                            object_name) + 1  # index默认从0开始,但是json文件是从1开始，所以+1
                    elif current_parent == 'size':
                        if size[subelem.tag] is not None:
                            raise Exception('xml structure broken at size tag.')
                        size[subelem.tag] = int(subelem.text)
    
                    # option is <xmin>, <ymin>, <xmax>, <ymax>, when subelem is <bndbox>
                    for option in subelem:
                        if current_sub == 'bndbox':
                            if bndbox[option.tag] is not None:
                                raise Exception(
                                    'xml structure corrupted at bndbox tag.')
                            bndbox[option.tag] = int(option.text)
    
                    # only after parse the <object> tag
                    if bndbox['xmin'] is not None:
                        if object_name is None:
                            raise Exception('xml structure broken at bndbox tag')
                        if current_image_id is None:
                            raise Exception('xml structure broken at bndbox tag')
                        if current_category_id is None:
                            raise Exception('xml structure broken at bndbox tag')
                        bbox = []
                        # x
                        bbox.append(bndbox['xmin'])
                        # y
                        bbox.append(bndbox['ymin'])
                        # w
                        bbox.append(bndbox['xmax'] - bndbox['xmin'])
                        # h
                        bbox.append(bndbox['ymax'] - bndbox['ymin'])
                        print(
                            'add annotation with {},{},{},{}'.format(object_name, current_image_id - 1, current_category_id, bbox))
                        addAnnoItem(object_name, current_image_id -
                                    1, current_category_id, bbox)
        # categories部分
        for categoryname in category_set:
            addCatItem(categoryname)
    
    
    if __name__ == '__main__':
        xml_path = 'dataset/train_anatation'
        json_file = 'dataset/train.json'
        # xml_path = 'dataset/test_anatation'
        # json_file = 'dataset/test.json'
        parseXmlFiles(xml_path)
        json.dump(coco, open(json_file, 'w'))

运行好该代码后分别可以得到两个文件：train.json，test.json.

# 2 制作txt文件 #

ImageSetsMainCreate.py文件如下：

# -*- coding: utf-8 -*-
    # @Author: zhiwei
    # @Date:   2019-01-31 09:38:58
    # @Last Modified by:   zhiwei
    # @Last Modified time: 2019-01-31 10:21:58
    #
    import os
    import re
    
    fp1_path = "dataset/ok/JPEGImages"
    f = open('dataset/ok/VOCdevkit2007/VOC2007/ImageSets/Main/train.txt', 'w')
    s = ""
    i = 0
    for filename in os.listdir(fp1_path):
        # bicycle_train.txt
        # if re.match('^bicycle.+', filename) != None:
        #     s1 = os.path.splitext(os.path.basename(filename))[0]
        #     s = s + s1 + ' ' + str(1) + "\n"
        # else:
        #     s1 = os.path.splitext(os.path.basename(filename))[0]
        #     s = s + s1 + ' ' + str(0) + "\n"
    
        # electric bicycle_train.txt
        # if "electric_bicycle" in filename:
        #     s1 = os.path.splitext(os.path.basename(filename))[0]
        #     s = s + s1 + ' ' + str(1) + "\n"
        # else:
        #     s1 = os.path.splitext(os.path.basename(filename))[0]
        #     s = s + s1 + ' ' + str(0) + "\n"
    
        # train.txt
        s1 = os.path.splitext(os.path.basename(filename))[0]
        s = s + s1 + "\n"
    
    print s
    
    f.write(s)
    print len([name for name in os.listdir(fp1_path)])

使用该代码生成了8个txt文件，如下：  
![在这里插入图片描述][20190213212657523.png]  
文件内容格式如下（以bicycle\_test.txt为例，把所有的100张测试图片都囊括）：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p3X19jaGVu_size_16_color_FFFFFF_t_70]  
需要注意的是test.txt和train.txt两个文件的格式如下：（以train.txt为例，一共有200个）  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p3X19jaGVu_size_16_color_FFFFFF_t_70 1]

--------------------

第三部分到此结束。如有任何问题，欢迎留言交流学习。

[1_Detectron]: https://blog.csdn.net/zw__chen/article/details/86723277
[2_LabelImgPlus]: https://blog.csdn.net/zw__chen/article/details/87188004
[4_detectron]: https://blog.csdn.net/zw__chen/article/details/87209669
[5]: https://blog.csdn.net/zw__chen/article/details/87210932
[6]: https://blog.csdn.net/zw__chen/article/details/87213064
[https_github.com_zhiweichen95_detectron_my]: https://github.com/zhiweichen95/detectron_my
[20190213212657523.png]: /images/20220320/13c94d0a4ba24ef8921f9c7befc4ef5b.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p3X19jaGVu_size_16_color_FFFFFF_t_70]: /images/20220320/a31194b813f3451188fb738736a47406.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p3X19jaGVu_size_16_color_FFFFFF_t_70 1]: /images/20220320/fffba77aa9b34f739784fb008cc5d881.png