do_image_rotation, do_work_of_slopes_new_curved: pass arrays via shared memory

src/eynollah/eynollah.py

@@ -95,6 +95,7 @@ from .utils.drop_capitals import (
 )
 from .utils.marginals import get_marginals
 from .utils.resize import resize_image
+from .utils.shm import share_ndarray
 from .utils import (
     boosting_headers_by_longshot_region_segmentation,
     crop_image_inside_box,
@@ -1582,9 +1583,11 @@ class Eynollah:
         if not len(contours):
             return [], [], [], [], [], [], []
         self.logger.debug("enter get_slopes_and_deskew_new_curved")
+        with share_ndarray(textline_mask_tot) as textline_mask_tot_shared:
+            with share_ndarray(mask_texts_only) as mask_texts_only_shared:
                 results = self.executor.map(partial(do_work_of_slopes_new_curved,
-                                            textline_mask_tot_ea=textline_mask_tot,
+                                            textline_mask_tot_ea=textline_mask_tot_shared,
-                                            mask_texts_only=mask_texts_only,
+                                            mask_texts_only=mask_texts_only_shared,
                                             num_col=num_col,
                                             scale_par=scale_par,
                                             slope_deskew=slope_deskew,
@@ -1594,6 +1597,7 @@ class Eynollah:
                                             plotter=self.plotter,),
                                     boxes, contours, contours_par, range(len(contours_par)))
                 #textline_polygons, boxes, text_regions, text_regions_par, box_coord, index_text_con, slopes = zip(*results)
+                results = list(results) # exhaust prior to release
         self.logger.debug("exit get_slopes_and_deskew_new_curved")
         return tuple(zip(*results))
 

src/eynollah/utils/separate_lines.py

@@ -15,6 +15,7 @@ from .contour import (
     return_contours_of_interested_textline,
     find_contours_mean_y_diff,
 )
+from .shm import share_ndarray, wrap_ndarray_shared
 from . import (
     find_num_col_deskew,
     crop_image_inside_box,
@@ -1454,7 +1455,8 @@ def separate_lines_new2(img_crop, thetha, num_col, slope_region, logger=None, pl
 
     return img_patch_interest_revised
 
-def do_image_rotation(angle, img, sigma_des, logger=None):
+@wrap_ndarray_shared(kw='img')
+def do_image_rotation(angle, img=None, sigma_des=1.0, logger=None):
     if logger is None:
         logger = getLogger(__package__)
     img_rot = rotate_image(img, angle)
@@ -1521,7 +1523,8 @@ def return_deskew_slop(img_patch_org, sigma_des,n_tot_angles=100,
 def get_smallest_skew(img, sigma_des, angles, logger=None, plotter=None, map=map):
     if logger is None:
         logger = getLogger(__package__)
-    results = list(map(partial(do_image_rotation, img=img, sigma_des=sigma_des, logger=logger), angles))
+    with share_ndarray(img) as img_shared:
+        results = list(map(partial(do_image_rotation, img=img_shared, sigma_des=sigma_des, logger=logger), angles))
     if plotter:
         plotter.save_plot_of_rotation_angle(angles, results)
     try:
@@ -1594,9 +1597,12 @@ def do_work_of_slopes_new(
 
     return cnt_clean_rot, box_text, contour, contour_par, crop_coor, index_r_con, slope
 
+@wrap_ndarray_shared(kw='textline_mask_tot_ea')
+@wrap_ndarray_shared(kw='mask_texts_only')
 def do_work_of_slopes_new_curved(
         box_text, contour, contour_par, index_r_con,
-        textline_mask_tot_ea, mask_texts_only, num_col, scale_par, slope_deskew,
+        textline_mask_tot_ea=None, mask_texts_only=None,
+        num_col=1, scale_par=1.0, slope_deskew=0.0,
         logger=None, MAX_SLOPE=999, KERNEL=None, plotter=None
 ):
     if KERNEL is None:

src/eynollah/utils/shm.py

@@ -0,0 +1,45 @@
+from multiprocessing import shared_memory
+from contextlib import contextmanager
+from functools import wraps
+import numpy as np
+
+@contextmanager
+def share_ndarray(array: np.ndarray):
+    size = np.dtype(array.dtype).itemsize * np.prod(array.shape)
+    shm = shared_memory.SharedMemory(create=True, size=size)
+    try:
+        shared_array = np.ndarray(array.shape, dtype=array.dtype, buffer=shm.buf)
+        shared_array[:] = array[:]
+        shared_array.flags["WRITEABLE"] = False
+        yield dict(shape=array.shape, dtype=array.dtype, name=shm.name)
+    finally:
+        shm.close()
+        shm.unlink()
+
+@contextmanager
+def ndarray_shared(array: dict):
+    shm = shared_memory.SharedMemory(name=array['name'])
+    try:
+        array = np.ndarray(array['shape'], dtype=array['dtype'], buffer=shm.buf)
+        yield array
+    finally:
+        shm.close()
+
+def wrap_ndarray_shared(kw=None):
+    def wrapper(f):
+        if kw is None:
+            @wraps(f)
+            def shared_func(array, *args, **kwargs):
+                with ndarray_shared(array) as ndarray:
+                    return f(ndarray, *args, **kwargs)
+            return shared_func
+        else:
+            @wraps(f)
+            def shared_func(*args, **kwargs):
+                array = kwargs.pop(kw)
+                with ndarray_shared(array) as ndarray:
+                    kwargs[kw] = ndarray
+                    return f(*args, **kwargs)
+            return shared_func
+    return wrapper
+