import torch
import gradio as gr
import torchvision.transforms as transforms

device = torch.device("cuda") if torch.cuda.is_available() else torch.device("cpu")

efficientnet = torch.hub.load('NVIDIA/DeepLearningExamples:torchhub', 'nvidia_efficientnet_b0', pretrained=True)
utils = torch.hub.load('NVIDIA/DeepLearningExamples:torchhub', 'nvidia_convnets_processing_utils')

efficientnet.eval().to(device)

def inference(img):

  img_transforms = transforms.Compose(
                [transforms.Resize(256), transforms.CenterCrop(224), transforms.ToTensor()]
  )

  img = img_transforms(img)
  with torch.no_grad():
    # mean and std are not multiplied by 255 as they are in training script
    # torch dataloader reads data into bytes whereas loading directly
    # through PIL creates a tensor with floats in [0,1] range
    mean = torch.tensor([0.485, 0.456, 0.406]).view(1, 3, 1, 1)
    std = torch.tensor([0.229, 0.224, 0.225]).view(1, 3, 1, 1)
    img = img.float()
    img = img.unsqueeze(0).sub_(mean).div_(std)

  batch = torch.cat(
    [img]
  ).to(device)
  with torch.no_grad():
      output = torch.nn.functional.softmax(efficientnet(batch), dim=1)
      
    
  results = utils.pick_n_best(predictions=output, n=5)
  
  return results
  
title="EfficientNet"
description="Gradio demo for EfficientNet,EfficientNets are a family of image classification models, which achieve state-of-the-art accuracy, being an order-of-magnitude smaller and faster. Trained with mixed precision using Tensor Cores. To use it, simply upload your image or click on one of the examples below. Read more at the links below"

article = "<p style='text-align: center'><a href='https://arxiv.org/abs/1905.11946'>EfficientNet: Rethinking Model Scaling for Convolutional Neural Networks</a> | <a href='https://github.com/NVIDIA/DeepLearningExamples/tree/master/PyTorch/Classification/ConvNets/efficientnet'>Github Repo</a></p>"

examples=[['food.jpeg']]
gr.Interface(inference,gr.inputs.Image(type="pil"),"text",title=title,description=description,article=article,examples=examples).launch()