Backend python save img and inference

I'm trying to implement a method with the python backend to be able to save my inference images, it works. I also return the result of my inference :

import triton_python_backend_utils as pb_utils
import numpy as np
from PIL import Image
import os
import time
import json

class TritonPythonModel:
    def initialize(self, args):
        print('Initializing...')
        self.model_config = json.loads(args['model_config'])
        self.model_dir = args['model_repository']
        self.model_version = args['model_version']

        # Créer un dossier logs spécifique au modèle
        self.log_dir = os.path.join(self.model_dir, self.model_version, 'logs')
        os.makedirs(self.log_dir, exist_ok=True)
        print(f'Log directory initialized to: {self.log_dir}')

    def execute(self, requests):
        responses = []
        for request in requests:
            try:
                input_tensor = pb_utils.get_input_tensor_by_name(request, "images")
                input_image = input_tensor.as_numpy()

                print(f"Original input shape: {input_image.shape}, dtype: {input_image.dtype}", flush=True)
                print(f"Min value: {input_image.min()}, Max value: {input_image.max()}", flush=True)

                if input_image.ndim == 4:
                    input_image = input_image.squeeze(0)  # Remove batch dimension
                input_image = input_image.transpose(1, 2, 0)  # Change from CHW to HWC format

                # Normalize the image if necessary
                if input_image.max() <= 1.0:
                    input_image = (input_image * 255).astype(np.uint8)
                else:
                    input_image = input_image.astype(np.uint8)

                print(f"Processed input shape: {input_image.shape}, dtype: {input_image.dtype}", flush=True)
                print(f"Min value: {input_image.min()}, Max value: {input_image.max()}", flush=True)

                timestamp = int(time.time() * 1000)

                try:
                    img = Image.fromarray(input_image, 'RGB')
                    unique_filename = f"image_{timestamp}.png"
                    save_path = os.path.join(self.log_dir, unique_filename)
                    img.save(save_path, format='PNG')
                    print(f"Image saved successfully to: {save_path}", flush=True)

                    output_tensor = pb_utils.Tensor("output0", input_tensor.as_numpy())

                    # Créer la réponse d'inférence
                    inference_response = pb_utils.InferenceResponse(output_tensors=[output_tensor])
                    responses.append(inference_response)

                except Exception as e:
                    print(f"Error saving image: {str(e)}", flush=True)


            except Exception as e:
                print(f"Error processing image: {str(e)}", flush=True)
                error = pb_utils.TritonError(f"An error occurred while processing the image: {str(e)}")
                responses.append(pb_utils.InferenceResponse(error=error))

        return responses

    def finalize(self):
        print('Cleaning up...', flush=True)

with my client I have to adapt my code if I use the backend or not:

def process_triton_results(output_data, image_name, labels, log_mode=False):
    if log_mode:
        # Method for log mode (Python backend)
        image_data = output_data[0]
        mean_value = np.mean(image_data)

        if mean_value > 0.5:
            predicted_class = 1  # GOOD
            confidence = mean_value
        else:
            predicted_class = 0  # BAD
            confidence = 1 - mean_value
    else:
        # Standard method (without custom Python backend)
        class_probabilities = output_data[0][0]
        predicted_class = np.argmax(class_probabilities)
        confidence = class_probabilities[predicted_class]

    processed_results = {
        "file_name": image_name,
        "predicted_label": labels[int(predicted_class)] if labels else f"Class_{predicted_class}",
        "confidence": round(float(confidence), 4)
    }
    return processed_results

but depending on whether I'm using a model with a backend or a model without a backend, for the same image and the same model (onnx), I don't get the same inference score...I must have an error in my code but I don't know where, if you can help me.