将注记从Mask-RCNN数据集格式转换为COCO格式

import json
import os

def convert_mask_rcnn_to_coco(mask_rcnn_ann_file, mask_rcnn_images_dir, coco_output_dir):
    # 读取 Mask R-CNN 标注文件
    with open(mask_rcnn_ann_file, 'r') as f:
        mask_rcnn_data = json.load(f)
    
    # 初始化 COCO 格式的数据结构
    coco_data = {
        "images": [],
        "annotations": [],
        "categories": [
            {"id": 1, "name": "object"}  # 假设只有一个类别
        ]
    }
    
    image_id_map = {}
    annotation_id = 1
    
    for image_info in mask_rcnn_data['images']:
        image_id = image_info['id']
        image_filename = image_info['file_name']
        image_id_map[image_id] = len(coco_data['images'])
        
        coco_image_info = {
            "id": image_id_map[image_id],
            "file_name": image_filename,
            "width": image_info['width'],
            "height": image_info['height']
        }
        coco_data['images'].append(coco_image_info)
    
    for annotation in mask_rcnn_data['annotations']:
        image_id = annotation['image_id']
        category_id = 1  # 假设只有一个类别
        
        coco_annotation = {
            "id": annotation_id,
            "image_id": image_id_map[image_id],
            "category_id": category_id,
            "segmentation": annotation['segmentation'],
            "bbox": annotation['bbox'],
            "area": annotation['area'],
            "iscrowd": 0
        }
        coco_data['annotations'].append(coco_annotation)
        annotation_id += 1
    
    # 保存 COCO 格式的标注文件
    os.makedirs(coco_output_dir, exist_ok=True)
    coco_ann_file = os.path.join(coco_output_dir, 'instances.json')
    with open(coco_ann_file, 'w') as f:
        json.dump(coco_data, f)

# 示例调用
mask_rcnn_ann_file = 'path/to/mask_rcnn/annotations.json'
mask_rcnn_images_dir = 'path/to/mask_rcnn/images'
coco_output_dir = 'path/to/coco/output'

convert_mask_rcnn_to_coco(mask_rcnn_ann_file, mask_rcnn_images_dir, coco_output_dir)