diff --git a/README.md b/README.md
index a162d72..ac8310d 100644
--- a/README.md
+++ b/README.md
@@ -134,7 +134,8 @@ options:
                 streak is no more than ``sf_xtol``.
        * `'sf_nfa': 1` - Number of false alarms, allowed number of unaligned points in a streak.
        * `'sf_num_threads': int` - Number of threads to use for peak finder algorithm
-       * `'sf_mask_rois': list[(int, int, int, int)]` - [optional] list of `(y_min, y_max, x_min, x_max)` coordinates of ROIs to mask out during peak finding; can be used to mask out bad regions as well as to reduce data size to e.g. one quadrant for the purpose of speedup. 
+       * `'sf_mask_rois': list[(int, int, int, int)]` - [optional] list of `(y_min, y_max, x_min, x_max)` coordinates of ROIs to mask out during peak finding.
+       * `'sf_crop_roi': [int, int, int, int]` - [optional] run streak finder on a cropped image, e.g. one quadrant, for purpose of spedup.
 
      Algorithm Output:
        * `'number_of_streaks': int` - Indicates the count of identified streaks.
@@ -321,7 +322,7 @@ Example JSON for Convergent-Beam Diffraction Streak-Finder:
     "sf_min_size": 25,
     "sf_nfa": 1,
     "sf_num_threads": 32,
-    "sf_mask_rois": [[0, 2216, 2107, 4215]]     
+    "sf_crop_roi": [0, 2107, 0, 2216] 
 }
  ```
 # Acknowledgment