Helene Photogrametery Data Download

Download Flight Data

Set up environment

import sys
import subprocess
from pathlib import Path
from IPython.display import display

v = sys.version_info
print(f"We are using Python {v.major}.{v.minor}.{v.micro}")

# Append GRASS to the python system path
sys.path.append(
    subprocess.check_output(["grass", "--config", "python_path"], text=True).strip()
)

# Import GRASS libraries
import grass.script as gs
import grass.jupyter as gj

# GRASS Variables
grassdata = "grassdata"
project_name = "Swannanoa"
mapset = "flight"

We are using Python 3.10.12

GRASS

Create project

gs.create_project(path=grassdata, name=project_name, epsg="3358", overwrite=False)

Start GRASS session

# Start GRASS in the recently created project
session = gj.init(Path(grassdata, project_name))

Define Query Parameters

project = '`CAP - H-TS Helene 2024`' # Queried at API level
mission = "'24-1-5849'"
flight = "'A0046B'" # Swannanowa

url = f"https://services.arcgis.com/XG15cJAlne2vxtgt/ArcGIS/rest/services/Image_Points_view/FeatureServer/3/query?where=project+%3D+%27CAP+-+H-TS+Helene+2024%27+and+mission+%3D+%2724-1-5849%27+and+flight+%3D+%27{flight}%27&objectIds=&time=&geometry=&geometryType=esriGeometryEnvelope&inSR=&spatialRel=esriSpatialRelIntersects&resultType=none&distance=0.0&units=esriSRUnit_Meter&relationParam=&returnGeodetic=false&outFields=*&returnGeometry=true&featureEncoding=esriDefault&multipatchOption=xyFootprint&maxAllowableOffset=&geometryPrecision=&outSR=3358&defaultSR=&datumTransformation=&applyVCSProjection=false&returnIdsOnly=false&returnUniqueIdsOnly=false&returnCountOnly=false&returnExtentOnly=false&returnQueryGeometry=false&returnDistinctValues=false&cacheHint=false&orderByFields=&groupByFieldsForStatistics=&outStatistics=&having=&resultOffset=&resultRecordCount=&returnZ=false&returnM=false&returnTrueCurves=false&returnExceededLimitFeatures=true&quantizationParameters=&sqlFormat=none&f=geojson&token="

Import Data

gs.run_command("v.import", input=url, output="image_points", overwrite=True)

Get data info

gs.run_command("v.info", map="image_points", flags="c" )

INTEGER|cat
INTEGER|OBJECTID
TEXT|id
TEXT|filename
TEXT|original_filename
DOUBLE PRECISION|longitude
DOUBLE PRECISION|latitude
INTEGER|altitude
DOUBLE PRECISION|heading
INTEGER|exif_photo_date
TEXT|exif_camera_maker
TEXT|exif_camera_model
INTEGER|exif_focal_length
TEXT|url
INTEGER|image_type
TEXT|project
TEXT|mission
TEXT|flight
TEXT|exif_hash
TEXT|GlobalID
INTEGER|CreationDate
TEXT|Creator
INTEGER|EditDate
TEXT|Editor

Set region

gs.run_command("g.region", vector="image_points", res=10)

View Data

# m = gj.Map()
# m.d_vect(map="image_points")
# display(m.show())

Read data into pandas DataFrame

import pandas as pd

points_json = gs.parse_command("v.db.select",
    map="image_points",
    format="json",
    flags=""
)

points_df = pd.DataFrame(points_json["records"])
points_df.head()

	cat	OBJECTID	id	filename	original_filename	longitude	latitude	altitude	heading	exif_photo_date	...	image_type	project	mission	flight	exif_hash	GlobalID	CreationDate	Creator	EditDate	Editor
0	1	120606	d97114c4-eed0-4ccd-90a7-3f2e11c8d580	None	DSC_0263.JPG	-82.163263	35.436860	771	235.5	958048008.0	...	3	CAP - H-TS Helene 2024	24-C-5836	A0001	f61d98abd014485411ceac7c4c07b70f7eb72596760ded...	a2c14f97-4cbb-487a-87cf-d4d1c1fcab2e	963647308	ImageEvents_Editor	963647308	ImageEvents_Editor
1	2	120607	6ce484f2-018e-423f-bce7-6eaad9c244f3	None	DSC_0264.JPG	-82.163695	35.436928	770	235.9	958049008.0	...	3	CAP - H-TS Helene 2024	24-C-5836	A0001	3a5d8ce54df9d67061388cd9bd043acd8be5372f97a835...	8558530c-5f3f-4ab3-aff4-3edc24d289ee	963647352	ImageEvents_Editor	963647352	ImageEvents_Editor
2	3	120608	cde7ac76-489a-4727-8960-0eee4a5e0502	None	DSC_0333.JPG	-82.173335	35.434563	652	255.6	958212008.0	...	3	CAP - H-TS Helene 2024	24-C-5836	A0001	fd95aec2cf70f69597e2d40ce55d3fda3d11eeffa54337...	e22ed4ae-6d25-4373-9602-bee109a51dca	963706222	ImageEvents_Editor	963706222	ImageEvents_Editor
3	4	120609	8377e5c7-c2b5-4751-bfa7-78d872330dae	None	DSC_0267.JPG	-82.164995	35.437093	763	226.8	958052008.0	...	3	CAP - H-TS Helene 2024	24-C-5836	A0001	c92560989bb8f88d7bee2d0b47da7eaa443752cfef9436...	a1a3d79c-8552-454a-bb6a-e06d98df8233	963797387	ImageEvents_Editor	963797387	ImageEvents_Editor
4	5	120610	3073c812-6915-4906-bf7a-8eb2b072d4d5	None	DSC_0333.JPG	-82.173335	35.434563	652	255.6	958212008.0	...	3	CAP - H-TS Helene 2024	24-C-5836	A0001	fd95aec2cf70f69597e2d40ce55d3fda3d11eeffa54337...	612a97c6-2fbc-498f-9cb7-003cb595529e	963799987	ImageEvents_Editor	963799987	ImageEvents_Editor

5 rows × 24 columns

Download images for processing

import os
import requests
from concurrent.futures import ThreadPoolExecutor, as_completed

# Function to download an image from a URL
def download_image(url, save_path, session):
    try:
        response = session.get(url)
        response.raise_for_status()  # Check for HTTP errors
        with open(save_path, 'wb') as file:
            file.write(response.content)
        print(f"Downloaded {url} to {save_path}")
    except requests.RequestException as e:
        print(f"Failed to download {url}: {e}")

# Main function to set up the thread pool and download images
def run(urls, save_dir, num_threads=4):
    if not os.path.exists(save_dir):
        os.makedirs(save_dir)

    with ThreadPoolExecutor(max_workers=num_threads) as executor:
        with requests.Session() as session:
            futures = []
            for url in urls:
                filename = os.path.basename(url)
                save_path = os.path.join(save_dir, filename)
                futures.append(executor.submit(download_image, url, save_path, session))

            for future in as_completed(futures):
                future.result()  # This will raise 

Run the download command

Make sure to set appropriate threads for your system.

url_list = list(points_df.url.values)

run(urls=url_list, save_dir="imagery_data/nadir/{flight}", num_threads=32)

Example output

Run data in your favorite photogrametry software

• WebODM
• Agisoft Metashape