9/26/2023

QR detector python code

 refer to code:


.

import cv2
#pip install pyzbar
from pyzbar.pyzbar import decode

def scan_qr_code():
# Start the webcam
cap = cv2.VideoCapture(0)
cap.set(3, 640) # Set the width of the window
cap.set(4, 480) # Set the height of the window
while True:
success, img = cap.read()
if not success:
print("Failed to grab frame")
break
# Decode the QR Code
for barcode in decode(img):
# Get the QR Code position
my_data = barcode.data.decode('utf-8')
pts = barcode.polygon
if len(pts) == 4: # If we have 4 points, then we have a QR code
pts2 = barcode.rect
cv2.putText(img, my_data, (pts2[0], pts2[1]), cv2.FONT_HERSHEY_SIMPLEX, 0.9, (255, 0, 255), 2)
for point in pts:
cv2.circle(img, (point[0], point[1]), 5, (0, 255, 0), cv2.FILLED)
# Display the frame
cv2.imshow('QR Code Scanner', img)
if cv2.waitKey(1) & 0xFF == ord('q'): # Press 'q' to quit
break
cap.release()
cv2.destroyAllWindows()

if __name__ == "__main__":
scan_qr_code()

..


you need to install pyzbar


Thank you.

www.marearts.com

🙇🏻‍♂️




9/23/2023

python code to convert heic (Mac image) to jpeg

 refer to code:


.

# pip install pyheif pillow
# brew install libheif



import os
import subprocess

input_folder = "./input/path"
output_folder = "./output/path"

if not os.path.exists(output_folder):
os.makedirs(output_folder)

for filename in os.listdir(input_folder):
if filename.endswith(".heic") or filename.endswith(".HEIC"):
heic_path = os.path.join(input_folder, filename)
jpeg_path = os.path.join(output_folder, os.path.splitext(filename)[0] + ".jpg")

# Run heif-convert to convert the HEIC file to JPEG
subprocess.run(["heif-convert", heic_path, jpeg_path])

print("Conversion complete!")


..


Thank you.



9/22/2023

Download Youtube Video, url to local video file.

The code need to install two YouTube downloader package.

Those are pytube, youtube_dl.

This code try to use one of them because sometime it's fail in certain library.


Enjoy code:

.

import ssl
from pytube import YouTube
import youtube_dl

#pip install pytube
#pip install youtube_dl


def configure_ssl():
try:
_create_unverified_https_context = ssl._create_unverified_context
except AttributeError:
pass
else:
ssl._create_default_https_context = _create_unverified_https_context

def pytube_download(video_url):
try:
yt = YouTube(video_url)
video = yt.streams.get_highest_resolution()
print(f"Downloading: {video.title}")
video.download()
print("Video downloaded successfully using pytube.")
return True
except Exception as e:
print(f"An error occurred while downloading the video with pytube: {e}")
return False

def download_youtube_video(video_url):
download_options = {
'format': 'best',
'outtmpl': '%(title)s-%(id)s.%(ext)s', # Set the output filename format
'progress_hooks': [hook],
}

try:
with youtube_dl.YoutubeDL(download_options) as ydl:
ydl.download([video_url])
print("Video downloaded successfully using youtube-dl.")
except Exception as e:
print(f"An error occurred while downloading the video with youtube-dl: {e}")

def hook(d):
if d['status'] == 'downloading':
print(d['_percent_str'], end="\r")

def main(video_url):
configure_ssl()
if not pytube_download(video_url):
download_youtube_video(video_url)

# Example usage:
if __name__ == "__main__":
video_url = 'https://youtu.be/MareArts' # Add your video url here
main(video_url)

..


Thank you.

www.marearts.com

🙇🏻‍♂️

9/19/2023

3D mesh generation form 3D cloud points, using open3D

 refer to code


.

import open3d as o3d
import numpy as np
import os

def load_point_cloud(file_path):
print("Loading point cloud...")
return o3d.io.read_point_cloud(file_path)

def estimate_normals(pcd):
print("Estimating normals...")
pcd.estimate_normals(search_param=o3d.geometry.KDTreeSearchParamHybrid(radius=0.1, max_nn=30))
return pcd

def remove_invalid_normals(pcd):
print("Removing invalid normals...")
valid_indices = np.where(np.linalg.norm(np.asarray(pcd.normals), axis=1) != 0)[0]
return pcd.select_by_index(valid_indices)

def poisson_reconstruction(pcd):
print("Performing Poisson surface reconstruction...")
mesh, _ = o3d.geometry.TriangleMesh.create_from_point_cloud_poisson(pcd, depth=8)
return mesh

def simplify_mesh(mesh):
print("Simplifying mesh...")
return mesh.simplify_quadric_decimation(target_number_of_triangles=10000)

def save_mesh(mesh, file_path):
print(f"Mesh saved to '{file_path}'")
o3d.io.write_triangle_mesh(file_path, mesh)

def main():
file_path = "/path/3d_cloud.ply"
pcd = load_point_cloud(file_path)
pcd = estimate_normals(pcd)
pcd = remove_invalid_normals(pcd)
mesh = poisson_reconstruction(pcd)
mesh = simplify_mesh(mesh)
mesh_file = os.path.join(os.path.dirname(file_path), 'mesh.ply')
save_mesh(mesh, mesh_file)

if __name__ == "__main__":
main()

..


install open3d using pip install open3d


Thank you.

www.marearts.com

🙇🏻‍♂️

print image exif python code

 refer to code:


.

from PIL import Image, ExifTags
import os

def print_exif_data(directory_path):
"""
Print the EXIF data of every JPEG image in the given directory.
Args:
directory_path (str): Path to the directory containing JPEG images.
"""
# Loop through all files in the directory
for filename in os.listdir(directory_path):
if filename.lower().endswith('.jpg') or filename.lower().endswith('.jpeg'):
filepath = os.path.join(directory_path, filename)
# Open image file
image = Image.open(filepath)
# Extract EXIF data
exif_data = image._getexif()
if exif_data is not None:
# Print EXIF data
print(f"EXIF data for {filename}:")
for tag_id, value in exif_data.items():
tag_name = ExifTags.TAGS.get(tag_id, tag_id)
print(f"{tag_name} ({tag_id}): {value}")
print('-' * 50)
else:
print(f"No EXIF data found for {filename}")
print('-' * 50)

if __name__ == "__main__":
# Define the directory path
directory_path = "/your_path/images"
# Print EXIF data
print_exif_data(directory_path)

..


this is example result 

.




EXIF data for IMG_5602.JPG:
ResolutionUnit (296): 2
ExifOffset (34665): 224
Make (271): Apple
Model (272): iPhone 12 Pro
Software (305): 16.6.1
Orientation (274): 6
DateTime (306): 2023:09:18 16:32:55
YCbCrPositioning (531): 1
XResolution (282): 72.0
YResolution (283): 72.0
HostComputer (316): iPhone 12 Pro
ExifVersion (36864): b'0232'
ComponentsConfiguration (37121): b'\x01\x02\x03\x00'
ShutterSpeedValue (37377): 5.915630897377497
DateTimeOriginal (36867): 2023:09:18 16:32:55
DateTimeDigitized (36868): 2023:09:18 16:32:55
ApertureValue (37378): 1.3561438092556088
BrightnessValue (37379): 2.0295000055765606
ExposureBiasValue (37380): 0.0
MeteringMode (37383): 5
Flash (37385): 16
FocalLength (37386): 4.2
ColorSpace (40961): 65535
ExifImageWidth (40962): 4032
FocalLengthIn35mmFilm (41989): 26
SceneCaptureType (41990): 0
OffsetTime (36880): +03:00
OffsetTimeOriginal (36881): +03:00
OffsetTimeDigitized (36882): +03:00
SubsecTimeOriginal (37521): 447
SubsecTimeDigitized (37522): 447
ExifImageHeight (40963): 3024
SensingMethod (41495): 2
ExposureTime (33434): 0.016666666666666666
FNumber (33437): 1.6
SceneType (41729): b'\x01'
ExposureProgram (34850): 2
ISOSpeedRatings (34855): 160
ExposureMode (41986): 0
FlashPixVersion (40960): b'0100'
WhiteBalance (41987): 0
LensSpecification (42034): (4.2, 4.2, 1.6, 1.6)
LensMake (42035): Apple
LensModel (42036): iPhone 12 Pro back camera 4.2mm f/1.6
MakerNote (37500): b"Apple iOS\x00\x00\x01MM\x00,\x00\x01\x00\t\x00\x00\x00\x0....

..


this is code to update exif

.

from PIL import Image
from PIL.ExifTags import TAGS, TAGS_V2

def update_exif_dimensions(image_path):
# Open the image
img = Image.open(image_path)
# Get EXIF data
exif_data = img._getexif()
# Convert it to a dictionary for easier access
exif_dict = {TAGS.get(k, k): v for k, v in exif_data.items()}
# Update ExifImageWidth and ExifImageHeight with actual dimensions
exif_dict['ExifImageWidth'] = img.width
exif_dict['ExifImageHeight'] = img.height
# Update the EXIF data in the image
img._getexif().update(exif_dict)
# Save the image with updated EXIF data
img.save(image_path)

# Update for a specific image
image_path = "path/to/your/image.jpg" # Replace with the actual path to your image
update_exif_dimensions(image_path)


..


Thank you.

🙇🏻‍♂️

www.marearts.com

9/14/2023

convert you opencv camera calibration yaml file to openSFM camera.json file

 refer to code:


.

from PIL import Image
import json
import yaml
import os
import argparse

def get_image_dimensions(image_path):
with Image.open(image_path) as img:
return img.size

def convert_yaml_to_opensfm_json(yaml_file, json_file, image_path):
image_width, image_height = get_image_dimensions(image_path)

with open(yaml_file, 'r') as f:
calibration_data = yaml.safe_load(f)

# Extract the camera matrix and distortion coefficients
camera_matrix = calibration_data['camera_matrix']
dist_coeff = calibration_data['dist_coeff']

# Compute the normalized focal length
focal_normalized = camera_matrix[0][0] / image_width

# Prepare the JSON data
json_data = {
f"custom_camera {image_width} {image_height} perspective 0.0": {
"projection_type": "perspective",
"width": image_width,
"height": image_height,
"focal": focal_normalized,
"k1": dist_coeff[0][0],
"k2": dist_coeff[0][1]
}
}

# Write the JSON data to file
with open(json_file, 'w') as f:
json.dump(json_data, f, indent=4)

def main():
yaml_file="calibration.yaml"
json_file="./camera_models.json"
image_path="IMG_5306.JPG"
convert_yaml_to_opensfm_json(yaml_file, json_file, image_path)

if __name__ == '__main__':
main()

..


reference :

https://github.com/mapillary/OpenSfM/issues/95

https://opensfm.org/docs/geometry.html#camera-models


Thank you.

www.marearts.com

🙇🏻‍♂️