def strip_projections(image, num_strips=30):
newimg = image.image_copy()
bottom_contour = image.contour_bottom()
left_side = min([
i for i in range(len(bottom_contour) - 1)
if bottom_contour[i + 1] != np.inf and bottom_contour[i] == np.inf
])
right_side = max([
i for i in range(len(bottom_contour) - 1)
if bottom_contour[i + 1] == np.inf and bottom_contour[i] != np.inf
])
vert_strips = []
strip_dim = gc.Dim(1 + (right_side - left_side) // num_strips,
image.height)
for i in range(num_strips):
ul = gc.Point(left_side + strip_dim.ncols * i, 0)
subimg = image.subimage(ul, strip_dim)
vert_strips.append(subimg)
strip_centers = [
int((x + 0.5) * strip_dim.ncols + left_side) for x in range(num_strips)
]
strip_projections = [x.projection_rows() for x in vert_strips]
strip_proj_smooth = [moving_avg_filter(x) for x in strip_projections]
strip_log = [np.log(x / (max(x) + 1) + 1) for x in strip_proj_smooth]
anchor_points = []
# find runs of consecutive zeroes and take points in middle of these runs: anchors
for s in strip_log:
iszero = np.concatenate(([0], np.less(s, 0.2).view(np.int8), [0]))
absdiff = np.abs(np.diff(iszero))
ranges = np.where(absdiff == 1)[0].reshape(-1, 2)
anchors = [int((x[0] + x[1]) / 2) for x in ranges]
anchor_points.append(anchors)
for i, x in enumerate(strip_centers):
for y in anchor_points[i]:
newimg.draw_marker(gc.Point(x, y), 10, 3, 1)
newimg.to_rgb().to_pil().save('aaaaaaa.png')
def display_lines(self, clear=1):
"""Display the lines found by placing a box around them
in a display. If clear is true then any boxes already on
the displayed are cleared first."""
if self.image._display is None:
self.image.display()
display = self.image._display
if clear:
display.clear_all_boxes()
for s in self.sections:
for line in s.lines:
b = line.bbox
display.add_box(
core.Rect(core.Point(b.ul_x, b.ul_y),
core.Dim(b.ncols, b.nrows)))
def display_sections(self, clear=1):
"""Display the sections found by placing a box around them
in a display. If clear is true then any boxes already on
the displayed are cleared first."""
# display the sections
result = self.sections
if self.image._display is None:
self.image.display()
display = self.image._display
if clear:
display.clear_all_boxes()
for rect in result:
b = rect.bbox
display.add_box(
core.Rect(core.Point(b.ul_x, b.ul_y),
core.Dim(b.ncols, b.nrows)))
def rotate_bbox(cbox, angle, orig_dim, target_dim, radians=False):
pivot = gc.Point(orig_dim.ncols / 2, orig_dim.nrows / 2)
# amount to translate to compensate for padding added by gamera's rotation in preprocessing.
# i am pretty sure this is the most "correct" amount. my math might be off.
dx = (orig_dim.ncols - target_dim.ncols) / 2
dy = (orig_dim.nrows - target_dim.nrows) / 2
if not radians:
angle = angle * np.pi / 180
s = np.sin(angle)
c = np.cos(angle)
# move to origin
old_ulx = cbox.ulx - pivot.x
old_uly = cbox.uly - pivot.y
old_lrx = cbox.lrx - pivot.x
old_lry = cbox.lry - pivot.y
# rotate using a 2d rotation matrix
new_ulx = (old_ulx * c) - (old_uly * s)
new_uly = (old_ulx * s) + (old_uly * c)
new_lrx = (old_lrx * c) - (old_lry * s)
new_lry = (old_lrx * s) + (old_lry * c)
# move back to original position adjusted for padding
new_ulx += (pivot.x - dx)
new_uly += (pivot.y - dy)
new_lrx += (pivot.x - dx)
new_lry += (pivot.y - dy)
new_ul = np.round([new_ulx, new_uly]).astype('int16')
new_lr = np.round([new_lrx, new_lry]).astype('int16')
return CharBox(cbox.char, new_ul, new_lr)
def __init__(self, glyph):
self.center = 0
self.bbox = core.Rect(core.Point(glyph.ul_x, glyph.ul_y),
core.Dim(glyph.ncols, glyph.nrows))
self.glyphs = []
self.add_glyph(glyph)
def find_sections(self):
"""Find the sections within an image - this finds large blocks
of text making it possible to find the lines within complex
text layouts."""
glyphs = self.glyphs
FUDGE = self.__avg_glyph_size(glyphs) * self.section_search_size
# remove noise and large objects
self.__noise_size = FUDGE
self.__large_size = FUDGE * 20
new_glyphs = []
for g in glyphs:
if self.__section_size_test(g):
new_glyphs.append(g)
else:
if self.__fill:
g.fill_white()
glyphs = new_glyphs
# Sort the glyphs left-to-right and top-to-bottom
glyphs.sort(lambda x, y: cmp(x.ul_x, y.ul_x))
glyphs.sort(lambda x, y: cmp(x.ul_y, y.ul_y))
# Create rectangles for each glyph that are bigger by FUDGE
big_rects = []
for g in glyphs:
ul_y = max(0, g.ul_y - FUDGE)
ul_x = max(0, g.ul_x - FUDGE)
lr_y = min(self.image.lr_y, g.lr_y + FUDGE)
lr_x = min(self.image.lr_x, g.lr_x + FUDGE)
ul_x = int(ul_x)
ul_y = int(ul_y)
nrows = int(lr_y - ul_y + 1)
ncols = int(lr_x - ul_x + 1)
big_rects.append(
core.Rect(core.Point(ul_x, ul_y), core.Dim(ncols, nrows)))
# Search for intersecting glyphs and merge them. This is
# harder than it seems at first because we want everything
# to merge together that intersects regardless of the order
# in the list. It ends up being similar to connected-component
# labeling. This is prone to be kind-of slow.
current = 0
rects = big_rects
while (1):
# Find the indexexes of any rects that interesect with current
inter = self.__find_intersecting_rects(rects, current)
# If we found intersecting rectangles merge them with them current
# rect, remove them from the list, and start the whole process
# over. We start over to make certain that everything that should
# be merged is.
if len(inter):
g = rects[current]
new_rects = [g]
for i in range(len(rects)):
if i == current:
continue
if i in inter:
g.union(rects[i])
else:
new_rects.append(rects[i])
rects = new_rects
current = 0
# If we didn't find anything that intersected move on to the next
# rectangle.
else:
current += 1
# Bail when we are done.
if current >= len(rects):
break
# Create the sections
sections = []
for rect in rects:
sections.append(Section(rect))
# Place the original (small) glyphs into the sections
for glyph in self.glyphs:
if self.__section_size_test(glyph):
for s in sections:
if s.bbox.intersects(glyph):
s.add_glyph(glyph)
break
# Fix up the bounding boxes
for s in sections:
s.calculate_bbox()
self.sections = sections
