Bounding box detection

In this experimental launch, we are providing developers with a powerful tool for object detection and localization within images and video. By accurately identifying and delineating objects with bounding boxes, developers can unlock a wide range of applications and enhance the intelligence of their projects.

Key Benefits:

  • Simple: Integrate object detection capabilities into your applications with ease, regardless of your computer vision expertise.
  • Customizable: Produce bounding boxes based on custom instructions (e.g. "I want to see bounding boxes of all the green objects in this image"), without having to train a custom model.

Technical Details:

  • Input: Your prompt and associated images or video frames.
  • Output: Bounding boxes in the [y_min, x_min, y_max, x_max] format. The top left corner is the origin. The x and y axis go horizontally and vertically, respectively. Coordinate values are normalized to 0-1000 for every image.
  • Visualization: AI Studio users will see bounding boxes plotted within the UI. Vertex AI users should visualize their bounding boxes through custom visualization code.

Gen AI SDK for Python

Learn how to install or update the Google Gen AI SDK for Python.
For more information, see the Gen AI SDK for Python API reference documentation or the python-genai GitHub repository.
Set environment variables to use the Gen AI SDK with Vertex AI: 

# Replace the `GOOGLE_CLOUD_PROJECT` and `GOOGLE_CLOUD_LOCATION` values
# with appropriate values for your project.
export GOOGLE_CLOUD_PROJECT=GOOGLE_CLOUD_PROJECT
export GOOGLE_CLOUD_LOCATION=us-central1
export GOOGLE_GENAI_USE_VERTEXAI=True
 

import requests

from google import genai
from google.genai.types import (
    GenerateContentConfig,
    HttpOptions,
    Part,
    SafetySetting,
)

from PIL import Image, ImageColor, ImageDraw

from pydantic import BaseModel

class BoundingBox(BaseModel):
    """
    Represents a bounding box with its 2D coordinates and associated label.

    Attributes:
        box_2d (list[int]): A list of integers representing the 2D coordinates of the bounding box,
                            typically in the format [x_min, y_min, x_max, y_max].
        label (str): A string representing the label or class associated with the object within the bounding box.
    """

    box_2d: list[int]
    label: str

def plot_bounding_boxes(image_uri: str, bounding_boxes: list[BoundingBox]) -> None:
    """
    Plots bounding boxes on an image with markers for each a name, using PIL, normalized coordinates, and different colors.

    Args:
        img_path: The path to the image file.
        bounding_boxes: A list of bounding boxes containing the name of the object
        and their positions in normalized [y1 x1 y2 x2] format.
    """

    with Image.open(requests.get(image_uri, stream=True, timeout=10).raw) as im:
        width, height = im.size
        draw = ImageDraw.Draw(im)

        colors = list(ImageColor.colormap.keys())

        for i, bbox in enumerate(bounding_boxes):
            y1, x1, y2, x2 = bbox.box_2d
            abs_y1 = int(y1 / 1000 * height)
            abs_x1 = int(x1 / 1000 * width)
            abs_y2 = int(y2 / 1000 * height)
            abs_x2 = int(x2 / 1000 * width)

            color = colors[i % len(colors)]

            draw.rectangle(
                ((abs_x1, abs_y1), (abs_x2, abs_y2)), outline=color, width=4
            )
            if bbox.label:
                draw.text((abs_x1 + 8, abs_y1 + 6), bbox.label, fill=color)

        im.show()

client = genai.Client(http_options=HttpOptions(api_version="v1"))

config = GenerateContentConfig(
    system_instruction="""
    Return bounding boxes as an array with labels.
    Never return masks. Limit to 25 objects.
    If an object is present multiple times, give each object a unique label
    according to its distinct characteristics (colors, size, position, etc..).
    """,
    temperature=0.5,
    safety_settings=[
        SafetySetting(
            category="HARM_CATEGORY_DANGEROUS_CONTENT",
            threshold="BLOCK_ONLY_HIGH",
        ),
    ],
    response_mime_type="application/json",
    response_schema=list[BoundingBox],
)

image_uri = "https://storage.googleapis.com/generativeai-downloads/images/socks.jpg"

response = client.models.generate_content(
    model="gemini-2.0-flash-001",
    contents=[
        Part.from_uri(
            file_uri=image_uri,
            mime_type="image/jpeg",
        ),
        "Output the positions of the socks with a face. Label according to position in the image.",
    ],
    config=config,
)
print(response.text)
plot_bounding_boxes(image_uri, response.parsed)

# Example response:
# [
#     {"box_2d": [36, 246, 380, 492], "label": "top left sock with face"},
#     {"box_2d": [260, 663, 640, 917], "label": "top right sock with face"},
# ]