Add faster precision calculation

Author: VikParuchuri

benchmark/layout.py

@@ -106,7 +106,7 @@ def main():
 
     print(tabulate(table_data, headers=table_headers, tablefmt="github"))
     print(f"Took {surya_time / len(images):.2f} seconds per image, and {surya_time:.1f} seconds total.")
-    print("Precision and recall are over the mutual coverage of the detected boxes and the ground truth boxes at a .5 threshold.  There is a precision penalty for multiple boxes overlapping reference lines.")
+    print("Precision and recall are over the mutual coverage of the detected boxes and the ground truth boxes at a .5 threshold.")
     print(f"Wrote results to {result_path}")
 
 

surya/benchmark/metrics.py

@@ -55,6 +55,18 @@ def calculate_coverage(box, other_boxes, penalize_double=False):
     return covered_pixels_count / box_area
 
 
+def calculate_coverage_fast(box, other_boxes, penalize_double=False):
+    box_area = (box[2] - box[0]) * (box[3] - box[1])
+    if box_area == 0:
+        return 0
+
+    total_intersect = 0
+    for other_box in other_boxes:
+        total_intersect += intersection_area(box, other_box)
+
+    return min(1, total_intersect / box_area)
+
+
 def precision_recall(preds, references, threshold=.5, workers=8, penalize_double=True):
     if len(references) == 0:
         return {
@@ -68,10 +80,15 @@ def precision_recall(preds, references, threshold=.5, workers=8, penalize_double
             "recall": 0,
         }
 
+    # If we're not penalizing double coverage, we can use a faster calculation
+    coverage_func = calculate_coverage_fast
+    if penalize_double:
+        coverage_func = calculate_coverage
+
     with ProcessPoolExecutor(max_workers=workers) as executor:
-        precision_func = partial(calculate_coverage, penalize_double=penalize_double)
+        precision_func = partial(coverage_func, penalize_double=penalize_double)
         precision_iou = executor.map(precision_func, preds, repeat(references))
-        reference_iou = executor.map(calculate_coverage, references, repeat(preds))
+        reference_iou = executor.map(coverage_func, references, repeat(preds))
 
     precision_classes = [1 if i > threshold else 0 for i in precision_iou]
     precision = sum(precision_classes) / len(precision_classes)

surya/postprocessing/fonts.py

@@ -1,11 +1,11 @@
-from typing import List
+from typing import List, Optional
 import os
 import requests
 
 from surya.settings import settings
 
 
-def get_font_path(langs: List[str] | None = None) -> str:
+def get_font_path(langs: Optional[List[str]] = None) -> str:
     font_path = settings.RECOGNITION_RENDER_FONTS["all"]
     if langs is not None:
         for k in settings.RECOGNITION_RENDER_FONTS:

surya/settings.py

@@ -50,7 +50,7 @@ def TORCH_DEVICE_DETECTION(self) -> str:
     DETECTOR_IMAGE_CHUNK_HEIGHT: int = 1400 # Height at which to slice images vertically
     DETECTOR_TEXT_THRESHOLD: float = 0.6 # Threshold for text detection (above this is considered text)
     DETECTOR_BLANK_THRESHOLD: float = 0.35 # Threshold for blank space (below this is considered blank)
-    DETECTOR_POSTPROCESSING_CPU_WORKERS: int = 8 # Number of workers for postprocessing
+    DETECTOR_POSTPROCESSING_CPU_WORKERS: int = min(8, os.cpu_count()) # Number of workers for postprocessing
 
     # Text recognition
     RECOGNITION_MODEL_CHECKPOINT: str = "vikp/surya_rec"