# Labelme json檔轉換

###### tags: `醫療影像計畫`

* 解決一次只能讀取一個json檔的問題
* 解決label標籤不統一的問題
* [參考資料](https://zhuanlan.zhihu.com/p/159837405)

問題如下:

由於有些圖片可能不包含所有的標籤，因此會導致顏色不統一，例如圖一中紅色區域為狗，圖二中紅色區域為貓

圖一
圖二

顏色的劃分是根據lanbel_names.txt的label名字決定的，其中排在第一位的標籤對應區域即為紅色，第二位對應為綠色，往後不斷對應顏色。

## 解決一次只能讀取一個json檔的問題

* 由於labelme_json_to_dataset一次只能處理一個json file，迴圈執行著這個命令

import os
def json2data(path)
    fileList = os.listdir(path)
    #獲得該路徑(path)下文件列表
    order_load=" labelme_json_to_dataset "+path+"/"        
    for i in fileList:
        order=order_load+i
        #獲得comand的命令(labelme_json_to_dataset)的部分
        val = os.system(order)
        print(val)
json2data('輸入路徑位置')

## 解決label標籤不統一的問題

* 解決方案為更改labelme_json_to_dataset，使label可以自行設定，同時保證標籤的統一

import argparse
import base64
import json
import os
import os.path as osp

import imgviz
import PIL.Image

from labelme.logger import logger
from labelme import utils


def main():
    logger.warning(
        "This script is aimed to demonstrate how to convert the "
        "JSON file to a single image dataset."
    )
    logger.warning(
        "It won't handle multiple JSON files to generate a "
        "real-use dataset."
    )

    parser = argparse.ArgumentParser()
    parser.add_argument("json_file")
    parser.add_argument("-o", "--out", default=None)
    args = parser.parse_args()

    json_file = args.json_file

    if args.out is None:
        out_dir = osp.basename(json_file).replace(".", "_")
        out_dir = osp.join(osp.dirname(json_file), out_dir)
    else:
        out_dir = args.out
    if not osp.exists(out_dir):
        os.mkdir(out_dir)

    data = json.load(open(json_file))
    imageData = data.get("imageData")

    if not imageData:
        imagePath = os.path.join(os.path.dirname(json_file), data["imagePath"])
        with open(imagePath, "rb") as f:
            imageData = f.read()
            imageData = base64.b64encode(imageData).decode("utf-8")
    img = utils.img_b64_to_arr(imageData)
    #-----------------------------更改部分從這裡開始------------------------------
    # label_name_to_value = {"_background_": 0}
    # for shape in sorted(data["shapes"], key=lambda x: x["label"]):
    #     label_name = shape["label"]
    #     if label_name in label_name_to_value:
    #         label_value = label_name_to_value[label_name]
    #     else:
    #         label_value = len(label_name_to_value)
    #         label_name_to_value[label_name] = label_value
    label_name_to_value={'_background_': 0, 'glottis': 1, 'throat_left': 2, 'throat_right': 3}
    
    lbl, _ = utils.shapes_to_label(
        img.shape, data["shapes"], label_name_to_value
    )

    # label_names = [None] * (max(label_name_to_value.values()) + 1)
    # for name, value in label_name_to_value.items():
    #     label_names[value] = name
    label_names =['_background_', 'glottis', 'throat_left', 'throat_right']
    #-----------------------------更改部分到這裡結束------------------------------ 

    lbl_viz = imgviz.label2rgb(
        label=lbl, img=imgviz.asgray(img), label_names=label_names, loc="rb"
    )

    PIL.Image.fromarray(img).save(osp.join(out_dir, "img.png"))
    utils.lblsave(osp.join(out_dir, "label.png"), lbl)
    PIL.Image.fromarray(lbl_viz).save(osp.join(out_dir, "label_viz.png"))

    with open(osp.join(out_dir, "label_names.txt"), "w") as f:
        for lbl_name in label_names:
            f.write(lbl_name + "\n")
    # 更改缺少的部分 ----------->增加info.yaml檔案
    import yaml
    logger.warning('info.yaml is being replaced by label_names.txt')
    info = dict(label_names=label_names)
    with open(osp.join(out_dir, 'info.yaml'), 'w') as f:
        yaml.safe_dump(info, f, default_flow_style=False)        
    #-----------------------------更改部分到這裡結束------------------------------ 

    logger.info("Saved to: {}".format(out_dir))


if __name__ == "__main__":
    main()