'TypeErrorを修正する方法：タイプbytesのオブジェクトはJSONシリアル化可能ではありません'

Question

Microsoft Azures Vision APIを使用して、ローカルJPEG画像から手書きのテキストを認識しています。私はMicrosoftのソースコードを編集して、URLからではなくローカルソースから画像を認識できるようにしています。ただし、このエラーの対処方法がわかりません： 'TypeError：タイプbytesのオブジェクトはJSONシリアル化できません'。

image_path = "/Users/FelixWallis/Downloads/IMG_2430.jpg" image_data = open(image_path, "rb").read() headers = {'Ocp-Apim-Subscription-Key': subscription_key} params = {'mode': 'Handwritten'} response = requests.post( text_recognition_url, headers=headers, params=params, json=image_data) response.raise_for_status() operation_url = response.headers["Operation-Location"] analysis = {} poll = True while (poll): response_final = requests.get( response.headers["Operation-Location"], headers=headers) analysis = response_final.json() time.sleep(1) if ("recognitionResult" in analysis): poll= False if ("status" in analysis and analysis['status'] == 'Failed'): poll= False polygons=[] if ("recognitionResult" in analysis): # Extract the recognized text, with bounding boxes. polygons = [(line["boundingBox"], line["text"]) for line in analysis["recognitionResult"]["lines"]] plt.figure(figsize=(15, 15)) image = Image.open(BytesIO(image_data)) ax = plt.imshow(image) for polygon in polygons: vertices = [(polygon[0][i], polygon[0][i+1]) for i in range(0, len(polygon[0]), 2)] text = polygon[1] patch = Polygon(vertices, closed=True, fill=False, linewidth=2, color='y') ax.axes.add_patch(patch) plt.text(vertices[0][0], vertices[0][1], text, fontsize=20, va="top") _ = plt.axis("off")

トレースバック：

TypeError Traceback (most recent call last) <ipython-input-2-9eba870c3121> in <module> 32 params = {'mode': 'Handwritten'} 33 response = requests.post( ---> 34 text_recognition_url, headers=headers, params=params, json=image_data) 35 response.raise_for_status() 36 /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/requests/api.py in post(url, data, json, **kwargs) 114 """ 115 --> 116 return request('post', url, data=data, json=json, **kwargs) 117 118 /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/requests/api.py in request(method, url, **kwargs) 58 # cases, and look like a memory leak in others. 59 with sessions.Session() as session: ---> 60 return session.request(method=method, url=url, **kwargs) 61 62 /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/requests/sessions.py in request(self, method, url, params, data, headers, cookies, files, auth, timeout, allow_redirects, proxies, hooks, stream, verify, cert, json) 517 hooks=hooks, 518 ) --> 519 prep = self.prepare_request(req) 520 521 proxies = proxies or {} /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/requests/sessions.py in prepare_request(self, request) 460 auth=merge_setting(auth, self.auth), 461 cookies=merged_cookies, --> 462 hooks=merge_hooks(request.hooks, self.hooks), 463 ) 464 return p /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/requests/models.py in prepare(self, method, url, headers, files, data, params, auth, cookies, hooks, json) 314 self.prepare_headers(headers) 315 self.prepare_cookies(cookies) --> 316 self.prepare_body(data, files, json) 317 self.prepare_auth(auth, url) 318 /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/requests/models.py in prepare_body(self, data, files, json) 464 # provides this natively, but Python 3 gives a Unicode string. 465 content_type = 'application/json' --> 466 body = complexjson.dumps(json) 467 if not isinstance(body, bytes): 468 body = body.encode('utf-8') /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/json/__init__.py in dumps(obj, skipkeys, ensure_ascii, check_circular, allow_nan, cls, indent, separators, default, sort_keys, **kw) 229 cls is None and indent is None and separators is None and 230 default is None and not sort_keys and not kw): --> 231 return _default_encoder.encode(obj) 232 if cls is None: 233 cls = JSONEncoder /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/json/encoder.py in encode(self, o) 197 # exceptions aren't as detailed. The list call should be roughly 198 # equivalent to the PySequence_Fast that ''.join() would do. --> 199 chunks = self.iterencode(o, _one_shot=True) 200 if not isinstance(chunks, (list, Tuple)): 201 chunks = list(chunks) /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/json/encoder.py in iterencode(self, o, _one_shot) 255 self.key_separator, self.item_separator, self.sort_keys, 256 self.skipkeys, _one_shot) --> 257 return _iterencode(o, 0) 258 259 def _make_iterencode(markers, _default, _encoder, _indent, _floatstr, /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/json/encoder.py in default(self, o) 177 178 """ --> 179 raise TypeError(f'Object of type {o.__class__.__name__} ' 180 f'is not JSON serializable') 181 TypeError: Object of type bytes is not JSON serializable

Peter Pan · Accepted Answer

コードとエラー情報によると、この問題は、ローカルイメージのimage_data値を誤ったパラメーターjson（dataである必要があります）に渡し、ローカルイメージのContent-Typeヘッダーが欠落していることが原因で発生しました。メソッドrequests.postについては、 Recognize Text APIの参照を注意深く参照してください。

これが参考としての私のコードです。

import requests image_path = '<the file path, like /Users/FelixWallis/Downloads/IMG_2430.jpg>' image_data = open(image_path, "rb").read() headers = { 'Ocp-Apim-Subscription-Key': '<your subscription key>', 'Content-Type': 'application/octet-stream' } params = {'mode': 'Handwritten'} text_recognition_url = 'https://<your cognitive service region, such as southeastasia for me>.api.cognitive.Microsoft.com/vision/v2.0/recognizeText' response = requests.post(text_recognition_url, headers=headers, params=params, data=image_data) print(response.raw.status) # the result is 202 print(response.raise_for_status()) # the result is None operation_url = response.headers["Operation-Location"] print(operation_url) # the result for me is like https://southeastasia.api.cognitive.Microsoft.com/vision/v2.0/textOperations/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx