Image stitching for mapping in Drone Programming - Mini Project: Build & Apply

Image Stitching for Mapping

📖 Scenario: You are programming a drone to create a map by stitching together images it takes while flying over a field. Each image has a unique ID and a position coordinate. Your task is to combine these images into a single stitched map based on their positions.

🎯 Goal: Build a simple program that takes a dictionary of images with their positions, sets a stitching threshold, selects images close enough to stitch, and outputs the list of images that will be stitched together.

📋 What You'll Learn

Create a dictionary called images with image IDs as keys and their (x, y) positions as values.

Create a variable called stitch_threshold to set the maximum distance between images to be stitched.

Use a for loop with variables img1 and pos1 to iterate over images.items().

Inside the loop, use another for loop with variables img2 and pos2 to iterate over images.items().

Calculate the distance between pos1 and pos2 and if it is less than or equal to stitch_threshold, add the pair (img1, img2) to a list called stitch_pairs.

Print the stitch_pairs list.

💡 Why This Matters

🌍 Real World

Drones capture many images of land or buildings. Stitching these images creates a complete map or model.

💼 Career

Understanding image stitching helps in drone programming, mapping, surveying, and geographic information systems (GIS).

1

Create the images dictionary

Create a dictionary called images with these exact entries: 'img1': (0, 0), 'img2': (3, 4), 'img3': (6, 8), 'img4': (10, 10).

Drone Programming

# Create the images dictionary with exact keys and position tuples
# Your code here

Need a hint?

Use curly braces {} to create a dictionary. Each key is a string like 'img1' and each value is a tuple with two numbers.

2

Set the stitching threshold

Create a variable called stitch_threshold and set it to 5.

Drone Programming

images = {'img1': (0, 0), 'img2': (3, 4), 'img3': (6, 8), 'img4': (10, 10)}
# Set stitch_threshold to 5
# Your code here

Need a hint?

Just write stitch_threshold = 5 on a new line.

3

Find image pairs to stitch

Create an empty list called stitch_pairs. Use a for loop with variables img1 and pos1 to iterate over images.items(). Inside it, use another for loop with variables img2 and pos2 to iterate over images.items(). Calculate the distance between pos1 and pos2 using the formula ((pos1[0] - pos2[0])**2 + (pos1[1] - pos2[1])**2)**0.5. If the distance is less than or equal to stitch_threshold and img1 is not equal to img2, add the tuple (img1, img2) to stitch_pairs.

Drone Programming

images = {'img1': (0, 0), 'img2': (3, 4), 'img3': (6, 8), 'img4': (10, 10)}
stitch_threshold = 5
# Create stitch_pairs list and add pairs of images within threshold
# Your code here

Need a hint?

Remember to check that img1 is not the same as img2 to avoid pairing an image with itself.

4

Print the stitching pairs

Write print(stitch_pairs) to display the list of image pairs that will be stitched together.

Drone Programming

images = {'img1': (0, 0), 'img2': (3, 4), 'img3': (6, 8), 'img4': (10, 10)}
stitch_threshold = 5
stitch_pairs = []
for img1, pos1 in images.items():
    for img2, pos2 in images.items():
        distance = ((pos1[0] - pos2[0])**2 + (pos1[1] - pos2[1])**2)**0.5
        if distance <= stitch_threshold and img1 != img2:
            stitch_pairs.append((img1, img2))
# Print the stitch_pairs list
# Your code here

Need a hint?

Just write print(stitch_pairs) to see the pairs.