API improvements

cat_detection.py

@@ -1,48 +1,58 @@
 from io import BytesIO
 
-import torch
-import torch.nn.functional as F
+import numpy as np
 from PIL import Image
-from torchvision.models.resnet import resnet50, ResNet50_Weights
-from torchvision.transforms import transforms
-
-model = resnet50(weights=ResNet50_Weights.DEFAULT)
-
-model.eval()
-
-# Define the image transformations
-preprocess = transforms.Compose([
-    transforms.Resize(256),
-    transforms.CenterCrop(224),
-    transforms.ToTensor(),
-    transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]),
-])
+from keras.src.applications.resnet import preprocess_input, decode_predictions
+from keras.applications.resnet import ResNet50
 
 
-def is_cat(image):
+"""
+    Recognition file.
+    Model is ResNet50. Pretrained model to image recognition.
+    If model recognize cat then returns response with first ten CAT predictions.
+    If first prediction is not a cat then returns False.
+    If prediction is not a cat (is not within list_of_labels) then skips this prediction.
+    Format of response:
+    {
+        'label': {label}
+        'score': {score}
+    }
+"""
+
+
+model = ResNet50(weights='imagenet')
+
+
+# PRIVATE Preprocess image method
+def _preprocess_image(image):
     try:
         img = Image.open(BytesIO(image.read()))
-
-        # Preprocess the image
-        img_t = preprocess(img)
-        batch_t = torch.unsqueeze(img_t, 0)
-
-        # Make the prediction
-        out = model(batch_t)
-
-        # Apply softmax to get probabilities
-        probabilities = F.softmax(out, dim=1)
-
-        # Get the maximum predicted class and its probability
-        max_prob, max_class = torch.max(probabilities, dim=1)
-        max_prob = max_prob.item()
-        max_class = max_class.item()
-
-        # Check if the maximum predicted class is within the range 281-285
-        if 281 <= max_class <= 285:
-            return max_class, max_prob
-        else:
-            return max_class, None
+        img = img.resize((224, 224))
+        img_array = np.array(img)
+        img_array = np.expand_dims(img_array, axis=0)
+        img_array = preprocess_input(img_array)
+        return img_array
     except Exception as e:
-        print("Error while processing the image:", e)
+        print(f"Error preprocessing image: {e}")
         return None
+
+
+# Generate response
+def _generate_response(decoded_predictions, list_of_labels):
+    results = {}
+    for i, (imagenet_id, label, score) in enumerate(decoded_predictions):
+        if i == 0 and label not in list_of_labels:
+            return None
+        if score < 0.01:
+            break
+        if label in list_of_labels:
+            results[len(results) + 1] = {"label": label, "score": round(float(score), 2)}
+    return results
+
+
+# Cat detection
+def detect_cat(image_file, list_of_labels):
+    img_array = _preprocess_image(image_file)
+    prediction = model.predict(img_array)
+    decoded_predictions = decode_predictions(prediction, top=10)[0]
+    return _generate_response(decoded_predictions, list_of_labels)

docs.md

@@ -1,9 +0,0 @@
-# Api
-
-Port -> 5000
-
-endpoint -> /detect-cat
-
-Key -> 'Image'
-
-Value -> {UPLOADED_FILE}

docs/docs.md

@@ -0,0 +1,53 @@
+# Api
+
+Port -> 5000
+
+endpoint -> api/v1/detect-cat
+
+Key -> 'Image'
+
+Value -> {UPLOADED_FILE}
+
+Flask Rest API application to cat recognition.
+If request is valid then send response with results of recognition.
+If key named 'Image' in body does not occur then returns 400 (BAD REQUEST).
+Otherwise, returns 200 with results of recognition.
+Format of response:
+```json
+{
+    "lang": "{users_lang}",
+    "results": {
+        "{filename}": {
+            "isCat": "{is_cat}",
+            "results": {
+                "1": "{result}",
+                "2": "{result}",
+                "3": "{result}",
+                "4": "{result}",
+                "5": "{result}",
+                "6": "{result}",
+                "7": "{result}",
+                "8": "{result}",
+                "9": "{result}",
+                "10": "{result}"
+            }
+        }
+    },
+    "errors": [
+        "{error_message}",
+        "{error_message}"
+    ]
+}
+```
+Format of result:
+```json
+    {
+        "label": "{label}",
+        "score": "{score}"
+    }
+```
+
+Example response:
+```json
+
+```

language_label_mapper.py

@@ -0,0 +1,26 @@
+from jproperties import Properties
+
+"""
+    Translator method.
+    If everything fine then returns translated labels.
+    Else throws an Exception and returns untranslated labels.
+"""
+
+
+def translate(to_translate, lang):
+    try:
+        config = Properties()
+
+        # Load properties file for given lang
+        with open(f"resources/{lang}.properties", 'rb') as config_file:
+            config.load(config_file, encoding='UTF-8')
+
+        # Translate labels for given to_translate dictionary
+        for index, label_info in to_translate.items():
+            label = label_info.get("label")
+            to_translate[index]["label"] = config.get(label).data
+        return to_translate, None
+    except Exception as e:
+        error_message = f"Error translating labels: {e}"
+        print(error_message)
+        return to_translate, error_message

main.py

@@ -1,37 +1,105 @@
-from flask import Flask, request, jsonify, session
+from flask import Flask, request, Response, json
+from cat_detection import detect_cat
+from language_label_mapper import translate
+from validator import validate
+
+""" 
+    Flask Rest API application to cat recognition.
+    If request is valid then send response with results of recognition.
+    If key named 'Image' in body does not occurred then returns 400 (BAD REQUEST).
+    Otherwise returns 200 with results of recognition.
+    Format of response:
+        {
+            "lang": {users_lang},
+            "results": {
+                {filename}: {
+                    "isCat": {is_cat},
+                    "results": {
+                        "1": {result}
+                        "2": {result}
+                        "3": {result}
+                        ...
+                        "10" {result}
+                    }
+                },
+                ...
+            },
+            errors[
+                {error_message},
+                {error_message},
+                ...
+            ]
+        }
+    To see result format -> cat_detection.py
+"""
 
-from cat_detection import is_cat
 
 # Define flask app
 app = Flask(__name__)
 app.secret_key = 'secret_key'
 
+# Available cats
+list_of_labels = [
+    'lynx',
+    'lion',
+    'tiger',
+    'cheetah',
+    'leopard',
+    'jaguar',
+    'tabby',
+    'Egyptian_cat',
+    'cougar',
+    'Persian_cat',
+    'Siamese_cat',
+    'snow_leopard',
+    'tiger_cat'
+]
 
-@app.route('/detect-cat', methods=['POST'])
+# Available languages
+languages = {'pl', 'en'}
+
+
+@app.route('/api/v1/detect-cat', methods=['POST'])
 def upload_file():
-    # 'Key' in body should be named as 'image'. Type should be 'File' and in 'Value' we should upload image from disc.
-    file = request.files['image']
-    if file.filename == '':
-        return jsonify({'error': "File name is empty. Please name a file."}), 400
-    max_class, max_prob = is_cat(file)
+    # Validate request
+    error_messages = validate(request)
 
-    # Save result in session
-    session['result'] = max_class, max_prob
+    # If any errors occurred, return 400 (BAD REQUEST)
+    if len(error_messages) > 0:
+        errors = json.dumps(
+            {
+                'errors': error_messages
+            }
+        )
+        return Response(errors, status=400, mimetype='application/json')
 
-    # Tworzenie komunikatu na podstawie wyniku analizy zdjęcia
-    translator = {
-        281: "tabby cat",
-        282: "tiger cat",
-        283: "persian cat",
-        284: "siamese cat",
-        285: "egyptian cat"
+    # Get files from request
+    files = request.files.getlist('image')
+
+    # Get user's language (Value in header 'Accept-Language'). Default value is English
+    lang = request.accept_languages.best_match(languages, default='en')
+
+    # Define JSON structure for results
+    results = {
+        'lang': lang,
+        'results': {},
+        'errors': []
     }
-    if max_prob is not None:
-        result = f"The image is recognized as '{translator[max_class]}' with a probability of {round(max_prob * 100, 2)}%"
-    else:
-        result = f"The image is not recognized as a class within the range 281-285 ({max_class})"
 
-    return jsonify({'result': result}), 200
+    # Generate results
+    for file in files:
+        predictions = detect_cat(file, list_of_labels)
+        if predictions is not None:
+            predictions, error_messages = translate(predictions, lang)
+        results['results'][file.filename] = {
+            'isCat': False if not predictions else True,
+            **({'predictions': predictions} if predictions is not None else {})
+        }
+        if error_messages is not None and predictions is None:
+            results['errors'].append(error_messages)
+
+    # Send response with 200 (Success)
+    return Response(json.dumps(results), status=200, mimetype='application/json')
 
 
 if __name__ == '__main__':

resources/en.properties

@@ -0,0 +1,14 @@
+# EN
+lynx=lynx
+lion=lion
+tiger=tiger
+cheetah=cheetah
+leopard=leopard
+jaguar=jaguar
+tabby=tabby
+Egyptian_cat=Egyptian cat
+cougar=cougar
+Persian_cat=Persian cat
+Siamese_cat=Siamese cat
+snow_leopard=snow leopard
+tiger_cat=tiger cat

resources/pl.properties

@@ -0,0 +1,14 @@
+# PL
+lynx=ryś
+lion=lew
+tiger=tygrys
+cheetah=gepard
+leopard=lampart
+jaguar=jaguar
+tabby=kot pręgowany
+Egyptian_cat=kot egipski
+cougar=puma
+Persian_cat=kot perski
+Siamese_cat=kot syjamski
+snow_leopard=lampart śnieżny
+tiger_cat=kot tygrysi

validator.py

@@ -0,0 +1,33 @@
+import imghdr
+
+"""
+    Validation method.
+    If everything fine then returns empty list.
+    Else returns list of error messages.
+"""
+
+# Allowed extensions
+allowed_extensions = {'jpg', 'jpeg', 'png'}
+
+
+def validate(request):
+    errors = []
+    try:
+        images = request.files.getlist('image')
+
+        # Case 1 - > request has no 'Image' Key in body
+        if images is None:
+            raise KeyError("'Image' key not found in request.")
+
+        # Case 2 - > if some of the images has no filename
+        if not images or all(img.filename == '' for img in images):
+            raise ValueError("Value of 'Image' key is empty.")
+
+        # Case 3 -> if some of the images has wrong extension
+        for img in images:
+            if imghdr.what(img) not in allowed_extensions:
+                raise ValueError(f"Given file '{img.filename}' has no allowed extension. "
+                                 f"Allowed extensions: {allowed_extensions}.")
+    except Exception as e:
+        errors.append(e.args[0])
+    return errors