app.py

import pathlib
import validators
import requests
import gradio as gr
# For running inference on the TF-Hub module.
import tensorflow as tf

# For downloading the image.
import matplotlib.pyplot as plt
import tempfile
from six import BytesIO

# For drawing onto the image.
import numpy as np
from PIL import Image
from PIL import ImageColor
from PIL import ImageDraw
from PIL import ImageFont
from PIL import ImageOps

print("load model...")
detector = tf.saved_model.load("model")


def draw_bounding_box_on_image(image,
                               ymin,
                               xmin,
                               ymax,
                               xmax,
                               color,
                               font,
                               thickness=4,
                               display_str_list=()):
    """Adds a bounding box to an image."""
    draw = ImageDraw.Draw(image)
    im_width, im_height = image.size
    (left, right, top, bottom) = (xmin * im_width, xmax * im_width,
                                  ymin * im_height, ymax * im_height)
    draw.line([(left, top), (left, bottom), (right, bottom), (right, top),
               (left, top)],
              width=thickness,
              fill=color)

    # If the total height of the display strings added to the top of the bounding
    # box exceeds the top of the image, stack the strings below the bounding box
    # instead of above.
    display_str_heights = [font.getsize(ds)[1] for ds in display_str_list]
    # Each display_str has a top and bottom margin of 0.05x.
    total_display_str_height = (1 + 2 * 0.05) * sum(display_str_heights)

    if top > total_display_str_height:
        text_bottom = top
    else:
        text_bottom = top + total_display_str_height
    # Reverse list and print from bottom to top.
    for display_str in display_str_list[::-1]:
        text_width, text_height = font.getsize(display_str)
        margin = np.ceil(0.05 * text_height)
        draw.rectangle([(left, text_bottom - text_height - 2 * margin),
                        (left + text_width, text_bottom)],
                       fill=color)
        draw.text((left + margin, text_bottom - text_height - margin),
                  display_str,
                  fill="black",
                  font=font)
        text_bottom -= text_height - 2 * margin


"""Overlay labeled boxes on an image with formatted scores and label names."""


def draw_boxes(image, boxes, class_names, scores, max_boxes=10, min_score=0.1):
    colors = list(ImageColor.colormap.values())

    try:
        font = ImageFont.truetype("/usr/share/fonts/truetype/liberation/LiberationSansNarrow-Regular.ttf",
                                  25)
    except IOError:
        print("Font not found, using default font.")
        font = ImageFont.load_default()

    for i in range(min(boxes.shape[0], max_boxes)):
        if scores[i][0] >= min_score:
            ymin, xmin, ymax, xmax = tuple(boxes[i][0])
            display_str = "{}: {}%".format(class_names[i],
                                           int(100 * scores[i][0]))
            color = colors[hash(class_names[i]) % len(colors)]
            image_pil = Image.fromarray(np.uint8(image)).convert("RGB")
            draw_bounding_box_on_image(
                image_pil,
                ymin,
                xmin,
                ymax,
                xmax,
                color,
                font,
                display_str_list=[display_str])
            np.copyto(image, np.array(image_pil))
    return image


def run_detector(url_input, image_input, minscore=0.1):

    if (validators.url(url_input)):
        img = Image.open(requests.get(url_input, stream=True).raw)
    elif (image_input):
        img = image_input

    converted_img = tf.image.convert_image_dtype(img, tf.uint8)[
        tf.newaxis, ...]
    result = detector(converted_img)

    result = {key: value.numpy() for key, value in result.items()}

    print("Found %d objects." % len(result["detection_scores"]))
    labels = ["cyclist" for _ in range(len(result["detection_scores"]))]
    print(labels)

    image_with_boxes = draw_boxes(
        np.array(img), result["detection_boxes"],
        labels, result["detection_scores"], min_score=minscore)

    return image_with_boxes


css = '''
h1#title {
  text-align: center;
}
'''
demo = gr.Blocks(css=css)

title = """<h1 id="title">Custom Cyclists detector</h1>"""
description = "todo"


def set_example_image(example: list) -> dict:
    return gr.Image.update(value=example[0])


def set_example_url(example: list) -> dict:
    return gr.Textbox.update(value=example[0])


urls = ["https://hips.hearstapps.com/hmg-prod.s3.amazonaws.com/images/cyclist-on-path-by-sea-royalty-free-image-1656931301.jpg?crop=0.727xw:0.699xh;0.134xw,0.169xh&resize=640:*"]

with demo:
    gr.Markdown(title)
    gr.Markdown(description)
    slider_input = gr.Slider(minimum=0.0, maximum=1,
                             value=0.2, label='Prediction Threshold')

    with gr.Tabs():
        with gr.TabItem('Image URL'):
            with gr.Row():
                url_input = gr.Textbox(
                    lines=2, label='Enter valid image URL here..')
                img_output_from_url = gr.Image(shape=(640, 640))

            with gr.Row():
                example_url = gr.Dataset(components=[url_input], samples=[
                                         [str(url)] for url in urls])

            url_but = gr.Button('Detect')

        with gr.TabItem('Image Upload'):
            with gr.Row():
                img_input = gr.Image(type='pil')
                img_output_from_upload = gr.Image(shape=(650, 650))

            with gr.Row():
                example_images = gr.Dataset(components=[img_input],
                                            samples=[[path.as_posix()]
                                                     for path in sorted(pathlib.Path('images').rglob('*.jpg'))])

            img_but = gr.Button('Detect')

    url_but.click(run_detector, inputs=[
                  url_input, img_input, slider_input], outputs=img_output_from_url, queue=True)
    img_but.click(run_detector, inputs=[
                  url_input, img_input, slider_input], outputs=img_output_from_upload, queue=True)
    example_images.click(fn=set_example_image, inputs=[
                         example_images], outputs=[img_input])
    example_url.click(fn=set_example_url, inputs=[
                      example_url], outputs=[url_input])


demo.launch(enable_queue=True)