CoastCam - Code for processing USGS CoastCam data

This resides under ../crs/src/CoastCam on my laptop and under ../src/CoastCam on my Workspaces instance.

Main routines are in two files:

• coastcam.py - Main calibration and rectification routines
• coastcam_funcs.py - Various helper and utility routines

coastcam.py

Main routines

• class TargetGrid(target_grid_info,z=0.0) - Build grid onto which image(s) will be rectified
• class CameraCalibration(cfg, intrinsics, extrinsics) - Generate camera calibration object w/ transformation matrices
• rectify_images(cfg, target_grid, image_files, intrinsic_cal_list, extrinsic_cal_list, fs=None, interp_method = 'rgi') - Georectify and blend images from multiple cameras

Functions called by main routines

• _convert_beta(self) - Changes world coordinates to local coordinate_system
• assembleP(lcp, beta) - Assembles and returns Projective (P) matrix from LCP and Beta values
• apply_weights_to_pixels(K, W) - Return pixel intensities (K) weighted by W.
• local_transform_points( xo, yo, ang, flag, xin, yin) - Transforms points between local World Coordinates and Geographical (either direction)
• local_transform_extrinsics(local_xo,local_yo,local_angd,flag,extrinsics_in) - Tranforms extrinsic vector between Local World Coordinates and Geographical
• angle2R(azimuth, tilt, swing) - Assembles and returns a rotation matrix R from azimuth, tilt, and swing (roll)
• assemble_image_weights(K) - Return weight matrix W used for image merging.
• get_pixels(nx, ny, nc, DU, DV, image, interp_method='rgi') - Return pixel values for each xyz point from the image
• find_distort_UV(target_grid, calibration) - get UV for pinhole camera

coastcam_funcs.py - Collection of utility routines

Image quality

• estimate_sharpness(img) - Estimate image sharpness and contrast
• average_color(img) - Calculate the average pixel intensity of an image
• detect_blur_fft(img, size=60, vis=False) - Use high-frequency content of image fft to determine blur

JSON

def json2dict(jsonfile) - Read a .json file into a dict

Date/time/filename

• dts2unix(date_time_string, timezone='eastern') - Return the unix epoch time and a datetime object with aware UTC time zone
• unix2dts(unixnumber, timezone='eastern') - Get local time from unix number
• filetime2timestr(filepath, timezone='eastern') - Return the local time and the Unix Epoch string from an image filename or path
• timestr2filename(date_time_str, camera = 'c1', image_type = 'timex', timezone='eastern') - Return a filename given a date_time_str and other info

Subfolders

./awss - Shell scripts with useful AWS CLI commands for examining S3

./data - Image files and calibration data for tests

./misc - Misc. code that probably should not be in this repo

./original_code - Code from Axiom provided by Brittany Bruder with minimum modifications to run with USACE examples

• rectifyer.py - Axiom code for rectification
• calibration.py - Axiom code for reading .mat calib files and generating transformation matrices
• test_rectificatyion.ipynb - Code to test Axiom routines with USACE data

./tests - Examples and test code

./util - Utilities

• write_IOEO_to_json.m - Matlab script to convert calibrations in .mat format to JSON files.
• parse_s3_inventory.ipynb

Test notebooks to explore various processing

test_read_json_cal_files.ipynb - Code to read calibration files in proposed .json format.
test_bucket_read.ipynb - Demos using fsspec to read/write files to S3 buckets.
test_R2Calc.ipynb - Python version of Stockdon equation.
test_time_funcs.ipynb - Demo of datetime routines and converting file names to times.
test_histogram_balance.ipynb - Demo of using histogram balance to better match images.