def prepare_mask(self):
img = self.obj.sheet.get_page_image(self.obj.page_number)
width, height = self.obj.width, self.obj.height
matrix = list(img.recognize.matrix)
# Remove any offset from the matrix
matrix[4] = 0
matrix[5] = 0
matrix = cairo.Matrix(*matrix)
px_width, px_height = matrix.transform_distance(width, height)
px_width, px_height = int(math.ceil(px_width)), int(
math.ceil(px_height))
surf = cairo.ImageSurface(cairo.FORMAT_A1, px_width, px_height)
cr = cairo.Context(surf)
cr.set_source_rgba(0, 0, 0, 0)
cr.set_operator(cairo.OPERATOR_SOURCE)
cr.paint()
# Move to center and apply matrix
cr.translate(0.5 * px_width, 0.5 * px_height)
cr.transform(matrix)
cr.set_source_rgba(0, 0, 0, 1)
line_width = 1 / 72.0 * 25.4
cr.set_line_width(line_width)
matrix.invert()
xoff, yoff = matrix.transform_distance(px_width / 2.0, px_height / 2.0)
xoff = xoff - width / 2
yoff = yoff - width / 2
return cr, surf, line_width, width, height, xoff, yoff
def prepare_mask(self):
img = self.obj.sheet.get_page_image(self.obj.page_number)
width, height = self.obj.width, self.obj.height
matrix = list(img.recognize.matrix)
# Remove any offset from the matrix
matrix[4] = 0
matrix[5] = 0
matrix = cairo.Matrix(*matrix)
px_width, px_height = matrix.transform_distance(width, height)
px_width, px_height = int(math.ceil(px_width)), int(math.ceil(px_height))
surf = cairo.ImageSurface(cairo.FORMAT_A1, px_width, px_height)
cr = cairo.Context(surf)
cr.set_source_rgba(0, 0, 0, 0)
cr.set_operator(cairo.OPERATOR_SOURCE)
cr.paint()
# Move to center and apply matrix
cr.translate(0.5 * px_width, 0.5 * px_height)
cr.transform(matrix)
cr.set_source_rgba(0, 0, 0, 1)
line_width = 1 / 72.0 * 25.4
cr.set_line_width(line_width)
matrix.invert()
xoff, yoff = matrix.transform_distance(px_width / 2.0, px_height / 2.0)
xoff = xoff - width / 2
yoff = yoff - height / 2
return cr, surf, line_width, width, height, xoff, yoff