INFO - Please read the following information carefully:

INFO - find_wl_contours2: A method for extracting shorelines that uses the sand water interface detected with the model to refine the threshold that's used to detect shorelines .
  - This is the default method used when there are enough sand pixels within the reference shoreline buffer.

INFO - find_wl_contours1: This shoreline extraction method uses a threshold to differentiate between water and land pixels in images, relying on Modified Normalized Difference Water Index (MNDWI) values. However, it may inaccurately classify snow and ice as water, posing a limitation in certain environments.
  - This is only used when not enough sand pixels are detected within the reference shoreline buffer.

INFO - ---------------------------------------------------------------------------------------------------------------------
INFO - Extracting shorelines for L5 Minimum Shoreline Length: 500


INFO - WARNING: CoastSat has hard-coded the value for the minimum shoreline length for L7 to 200


INFO - Extracting shorelines for L7 Minimum Shoreline Length: 200


INFO - Extracting shorelines for L8 Minimum Shoreline Length: 500


INFO - L8 2025-11-13-22-11-40 cloud cover : 0.00%
INFO - L8 2025-11-13-22-11-40: sand: 0.15% ,whitewater: 0.02% ,water: 0.63%
INFO - L8 2025-11-13-22-11-40: Less than 50 sand pixels detected within reference shoreline buffer. Using find_wl_contours1
ERROR - L8 2025-11-13-22-11-40: Could not map shoreline due to error no valid pixels found in reference shoreline buffer.
Traceback (most recent call last):
  File "/home/ubuntu/.local/lib/python3.12/site-packages/coastsat/SDS_shoreline.py", line 1061, in extract_shorelines
    shoreline, t_mndwi = find_shoreline_optical(
                         ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/.local/lib/python3.12/site-packages/coastsat/SDS_shoreline.py", line 216, in find_shoreline_optical
    contours_mwi, t_mndwi = find_wl_contours1(im_mndwi, cloud_mask, im_ref_buffer)
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/.local/lib/python3.12/site-packages/coastsat/SDS_shoreline.py", line 1426, in find_wl_contours1
    raise ValueError("no valid pixels found in reference shoreline buffer.")
ValueError: no valid pixels found in reference shoreline buffer.

WARNING - L8 2025-11-20-22-17-54: Skipped due to cloud cover 31.23% > threshold 10.00%
INFO - L8 2025-12-06-22-17-51 cloud cover : 6.24%
INFO - L8 2025-12-06-22-17-51: sand: 0.69% ,whitewater: 0.00% ,water: 53.21%
INFO - L8 2025-12-06-22-17-51: Greater than 50 sand pixels detected within reference shoreline buffer. Using find_wl_contours2
INFO - Number of shorelines before removing shorelines < 500m: 13 shorelines. Number of shorelines after filtering shorelines: 0 shorelines
INFO - L8 2025-12-15-22-11-40 cloud cover : 0.00%
INFO - L8 2025-12-15-22-11-40: sand: 0.00% ,whitewater: 0.00% ,water: 0.00%
INFO - L8 2025-12-15-22-11-40: Less than 50 sand pixels detected within reference shoreline buffer. Using find_wl_contours1
ERROR - L8 2025-12-15-22-11-40: Could not map shoreline due to error no valid pixels found in reference shoreline buffer.
Traceback (most recent call last):
  File "/home/ubuntu/.local/lib/python3.12/site-packages/coastsat/SDS_shoreline.py", line 1061, in extract_shorelines
    shoreline, t_mndwi = find_shoreline_optical(
                         ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/.local/lib/python3.12/site-packages/coastsat/SDS_shoreline.py", line 216, in find_shoreline_optical
    contours_mwi, t_mndwi = find_wl_contours1(im_mndwi, cloud_mask, im_ref_buffer)
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/.local/lib/python3.12/site-packages/coastsat/SDS_shoreline.py", line 1426, in find_wl_contours1
    raise ValueError("no valid pixels found in reference shoreline buffer.")
ValueError: no valid pixels found in reference shoreline buffer.

INFO - Extracting shorelines for L9 Minimum Shoreline Length: 500


WARNING - L9 2025-11-12-22-17-59: Skipped due to cloud cover 51.65% > threshold 10.00%
INFO - L9 2025-12-07-22-11-45 cloud cover : 0.00%
INFO - L9 2025-12-07-22-11-45: sand: 0.00% ,whitewater: 0.00% ,water: 0.50%
INFO - L9 2025-12-07-22-11-45: Less than 50 sand pixels detected within reference shoreline buffer. Using find_wl_contours1
ERROR - L9 2025-12-07-22-11-45: Could not map shoreline due to error no valid pixels found in reference shoreline buffer.
Traceback (most recent call last):
  File "/home/ubuntu/.local/lib/python3.12/site-packages/coastsat/SDS_shoreline.py", line 1061, in extract_shorelines
    shoreline, t_mndwi = find_shoreline_optical(
                         ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/.local/lib/python3.12/site-packages/coastsat/SDS_shoreline.py", line 216, in find_shoreline_optical
    contours_mwi, t_mndwi = find_wl_contours1(im_mndwi, cloud_mask, im_ref_buffer)
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/ubuntu/.local/lib/python3.12/site-packages/coastsat/SDS_shoreline.py", line 1426, in find_wl_contours1
    raise ValueError("no valid pixels found in reference shoreline buffer.")
ValueError: no valid pixels found in reference shoreline buffer.

INFO - L9 2025-12-14-22-17-57 cloud cover : 7.99%
INFO - L9 2025-12-14-22-17-57: sand: 1.74% ,whitewater: 0.13% ,water: 49.29%
INFO - L9 2025-12-14-22-17-57: Greater than 50 sand pixels detected within reference shoreline buffer. Using find_wl_contours2
INFO - Number of shorelines before removing shorelines < 500m: 15 shorelines. Number of shorelines after filtering shorelines: 3 shorelines
INFO - Number of shoreline points before removing points within 300m of cloud mask 548
INFO - Number of shoreline points after removing points within 300m of cloud mask 397
INFO - Number of shoreline points before removing points within 30m of no data pixel 397
INFO - Number of shoreline points after removing points within 30m of no data pixel 397