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 2025-07-22-22-26-26 cloud cover : 0.00%
INFO - L8 2025-07-22-22-26-26: sand: 0.00% ,whitewater: 4.28% ,water: 53.46%
INFO - L8 2025-07-22-22-26-26: Less than 50 sand pixels detected within reference shoreline buffer. Using find_wl_contours1
INFO - Number of shorelines before removing shorelines < 500m: 4 shorelines. Number of shorelines after filtering shorelines: 2 shorelines
INFO - Number of shoreline points before removing points within 300m of cloud mask 592
INFO - Number of shoreline points after removing points within 300m of cloud mask 592
INFO - Number of shoreline points before removing points within 30m of no data pixel 592
INFO - Number of shoreline points after removing points within 30m of no data pixel 592
WARNING - L8 2025-07-29-22-32-38: Skipped due to cloud cover 12.49% > threshold 10.00%
WARNING - L8 2025-08-07-22-26-33: Skipped due to cloud cover 25.75% > threshold 10.00%
WARNING - L8 2025-08-23-22-26-37: Skipped due to cloud cover 39.06% > threshold 10.00%
INFO - Extracting shorelines for L9 Minimum Shoreline Length: 500


INFO - L9 2025-07-30-22-26-27 cloud cover : 2.65%
INFO - L9 2025-07-30-22-26-27: sand: 0.00% ,whitewater: 1.94% ,water: 52.63%
INFO - L9 2025-07-30-22-26-27: Less than 50 sand pixels detected within reference shoreline buffer. Using find_wl_contours1
INFO - Number of shorelines before removing shorelines < 500m: 5 shorelines. Number of shorelines after filtering shorelines: 2 shorelines
INFO - Number of shoreline points before removing points within 300m of cloud mask 388
INFO - Number of shoreline points after removing points within 300m of cloud mask 261
INFO - Number of shoreline points before removing points within 30m of no data pixel 261
INFO - Number of shoreline points after removing points within 30m of no data pixel 261
WARNING - L9 2025-08-15-22-26-39: Skipped due to cloud cover 84.23% > threshold 10.00%
INFO - L9 2025-08-22-22-32-52 cloud cover : 0.00%
INFO - L9 2025-08-22-22-32-52: sand: 0.00% ,whitewater: 0.00% ,water: 1.53%
INFO - L9 2025-08-22-22-32-52: Less than 50 sand pixels detected within reference shoreline buffer. Using find_wl_contours1
ERROR - L9 2025-08-22-22-32-52: 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.