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pil2cv: allow (and drop) alpha channels on input imgs #168

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pil2cv: allow (and drop) alpha channels on input imgs #168

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dadb879
pil2cv: allow (and drop) alpha channels on input imgs
Jun 12, 2025
42a3cc2
cv2pil: limit color depth on output imgs
Jun 12, 2025
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11 changes: 1 addition & 10 deletions src/eynollah/ocrd_cli_binarization.py
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Original file line number Diff line number Diff line change
Expand Up @@ -10,16 +10,7 @@
from ocrd.decorators import ocrd_cli_options, ocrd_cli_wrap_processor

from .sbb_binarize import SbbBinarizer


def cv2pil(img):
return Image.fromarray(img.astype('uint8'))

def pil2cv(img):
# from ocrd/workspace.py
color_conversion = cv2.COLOR_GRAY2BGR if img.mode in ('1', 'L') else cv2.COLOR_RGB2BGR
pil_as_np_array = np.array(img).astype('uint8') if img.mode == '1' else np.array(img)
return cv2.cvtColor(pil_as_np_array, color_conversion)
from .utils.pil_cv2 import cv2pil, pil2cv

class SbbBinarizeProcessor(Processor):
# already employs GPU (without singleton process atm)
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10 changes: 8 additions & 2 deletions src/eynollah/utils/pil_cv2.py
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Original file line number Diff line number Diff line change
Expand Up @@ -7,12 +7,18 @@
# from sbb_binarization

def cv2pil(img):
return Image.fromarray(np.array(cvtColor(img, COLOR_BGR2RGB)))
# reduce depth because cvtColor is limited
return Image.fromarray(np.array(cvtColor(img.astype(np.uint8), COLOR_BGR2RGB)))

def pil2cv(img):
# from ocrd/workspace.py
color_conversion = COLOR_GRAY2BGR if img.mode in ('1', 'L') else COLOR_RGB2BGR
color_conversion = COLOR_GRAY2BGR if img.mode in ('1', 'L', 'LA') else COLOR_RGB2BGR
pil_as_np_array = np.array(img).astype('uint8') if img.mode == '1' else np.array(img)
# cvtColor cannot handle alpha
if pil_as_np_array.shape[-1] == 2:
pil_as_np_array = pil_as_np_array[:,:,0]
elif pil_as_np_array.shape[-1] == 4:
pil_as_np_array = pil_as_np_array[:,:,:3]
return cvtColor(pil_as_np_array, color_conversion)

def check_dpi(img):
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