Files
orisys-sdk/src/orisys/Stitcher.py
T
2026-04-02 16:44:02 +08:00

1209 lines
47 KiB
Python

import os
import numpy as np
import scipy.fft
from scipy import ndimage
import cv2
class Stitcher:
def __init__(self,isstitch=False, config_stitcher=None,verbose=False):
# Settings
self.isstitch = isstitch
self.config_stitcher = config_stitcher
self.verbose = verbose
# Find Boxes Related
self.min_area_frac = config_stitcher["min_area_frac"]
self.max_area_frac = config_stitcher["max_area_frac"]
self.max_aspect_ratio = config_stitcher["max_aspect_ratio"]
# stitch related
self.stitch_valid = False
self.boxes = self.units = None
self.index = config_stitcher["index"]
self.stitch_calibration = self.tile_list = []
self.ncol = config_stitcher["n"][0]
self.nrow = config_stitcher["n"][1]
self.nominal_ov_pos=config_stitcher["nominal_ov_pos"]
self.margin=config_stitcher["margin"]
self.bound=self.nominal_ov_pos - self.margin
self.row_tol = config_stitcher["row_tol"]
self.box_size = config_stitcher["box_size"]
# stich related (BF-matching)
self._blend_coef_cache = {}
self._feature_stitch_cache = {
"ref_idx": None,
"moving_indices": None,
"tile_shapes": None,
"transforms": None,
"canvas": {},
}
self._feature_stitch_frame_idx = 0
self._feature_stitch_print_every = 30
self._feature_stitch_pad = 5
self._feature_stitch_match_brightness = False
if self.verbose:
print(f"Stitcher initialized with config: {self.config_stitcher}")
def configure_feature_stitch(self, *, match_brightness=None, pad=None, print_every=None):
"""Update runtime options for feature-based stitching."""
if match_brightness is not None:
self._feature_stitch_match_brightness = bool(match_brightness)
if pad is not None:
self._feature_stitch_pad = max(0, int(pad))
if print_every is not None:
self._feature_stitch_print_every = max(1, int(print_every))
def _get_blend_coef(self, ov_pos, dim, ndim):
key = (ov_pos, dim, ndim)
coef = self._blend_coef_cache.get(key)
if coef is not None:
return coef
blend_coef = np.linspace(1.0, 0.0, ov_pos, dtype=np.float32)
if dim == 1:
blend_coef = blend_coef.reshape(1, ov_pos, 1) if ndim == 3 else blend_coef.reshape(1, ov_pos)
else:
blend_coef = blend_coef.reshape(ov_pos, 1, 1) if ndim == 3 else blend_coef.reshape(ov_pos, 1)
self._blend_coef_cache[key] = blend_coef
return blend_coef
def stitch_rt_optimized(self, change_sv=False, s_mean=28., v_mean=180., blend=True):
feature_stitched = self.stitch_feature_optimized(
blend=blend,
match_brightness=self._feature_stitch_match_brightness,
pad=self._feature_stitch_pad,
print_every=self._feature_stitch_print_every,
)
if feature_stitched is not None:
return feature_stitched
# tile_list = self.tile_list
# stitch_calibration = self.stitch_calibration
# ncol = self.ncol
# nrow = self.nrow
# img_stitched_height = None
# for i in range(nrow):
# # Start with first tile of the row
# img_stitched_width = tile_list[i * ncol]
# # Stitch horizontally within the row
# for j in range(1, ncol):
# img_1 = img_stitched_width
# img_2 = tile_list[i * ncol + j]
# ov_pos = int(stitch_calibration[i * ncol + j - 1][1])
# ov_pos, ov1, ov2 = self.__find_ov(img_1, img_2, ov_pos, dim=1)
# img_stitched_width = self.__stitch_optimized(
# img_1, img_2, ov_pos, ov1, ov2, dim=1, blend=blend
# )
# # Stitch rows vertically
# if i == 0:
# img_stitched_height = img_stitched_width
# else:
# width_h = img_stitched_height.shape[1]
# width_w = img_stitched_width.shape[1]
# wdiff = width_h - width_w
# if wdiff != 0:
# if wdiff > 0:
# padding = (
# ((0, 0), (0, wdiff), (0, 0))
# if len(img_stitched_width.shape) == 3
# else ((0, 0), (0, wdiff))
# )
# img_stitched_width = np.pad(img_stitched_width, padding, mode='edge')
# else:
# img_stitched_width = img_stitched_width[:, :width_h]
# ov_pos_h = int(stitch_calibration[(i + 1) * nrow - 1][1])
# ov_pos_h, ov_h1, ov_h2 = self.__find_ov(
# img_stitched_height, img_stitched_width, ov_pos_h, dim=0
# )
# img_stitched_height = self.__stitch_optimized(
# img_stitched_height, img_stitched_width, ov_pos_h, ov_h1, ov_h2, dim=0, blend=blend
# )
# return img_stitched_height
def stitch_feature_optimized(self, blend=True, match_brightness=False, pad=5, print_every=30):
"""
Stitch the current tile grid by estimating tile-to-reference transforms once and
reusing them across frames. Falls back to overlap stitching when feature matching
cannot build a valid layout.
"""
plan = self._get_feature_stitch_plan()
if plan is None:
return None
ref_idx, t_ref, moving_indices, moving_tiles, selected_positions = plan
self._feature_stitch_frame_idx += 1
frame_idx = self._feature_stitch_frame_idx
tile_shapes = tuple(self.tile_list[pos].shape[:2] for pos in selected_positions)
cache = self._feature_stitch_cache
cache_changed = (
cache["ref_idx"] != ref_idx
or cache["moving_indices"] != moving_indices
or cache["tile_shapes"] != tile_shapes
)
if cache_changed:
cache["ref_idx"] = ref_idx
cache["moving_indices"] = moving_indices
cache["tile_shapes"] = tile_shapes
cache["transforms"] = None
cache["canvas"] = {}
if self.verbose:
print(
"Feature stitch tile selection: "
f"ref_idx={ref_idx}, moving_indices={list(moving_indices)}"
)
H_use_list = cache["transforms"]
if H_use_list is None:
do_verbose_first = self.verbose and frame_idx % print_every == 0
H_use_list = []
for j, tile in enumerate(moving_tiles):
H_use_j, _ = self._estimate_bfmatcher_stitch_transform(
t_ref,
tile,
verbose=(do_verbose_first and j == 0),
)
H_use_list.append(H_use_j)
cache["transforms"] = H_use_list
if not any(H is not None for H in H_use_list):
return None
return self._render_feature_tiles(
t_ref,
moving_tiles,
H_use_list,
pad=pad,
frame_idx=frame_idx,
print_every=print_every,
verbose=self.verbose,
match_brightness=match_brightness,
canvas_cache=cache["canvas"],
blend=blend,
)
# def __find_ov(self, img1, img2, ov_pos, dim=1):
# _dim = len(img1.shape)
# if dim == 1:
# if _dim == 3:
# # RGB case
# ov_1 = img1[:, -ov_pos:, :]
# ov_2 = img2[:, :ov_pos, :]
# else:
# # gray scale
# ov_1 = img1[:, -ov_pos:]
# ov_2 = img2[:, :ov_pos]
# elif dim == 0:
# if _dim == 3:
# ov_1 = img1[-ov_pos:, :, :]
# ov_2 = img2[:ov_pos, :, :]
# else:
# # gray scale
# ov_1 = img1[-ov_pos:, :]
# ov_2 = img2[:ov_pos, :]
# return ov_pos, ov_1, ov_2
def _get_feature_stitch_plan(self):
if not self.isstitch:
return None
if isinstance(self.index, int):
configured_indices = (self.index,)
elif isinstance(self.index, np.ndarray):
configured_indices = tuple(int(i) for i in self.index.tolist())
else:
configured_indices = tuple(int(i) for i in self.index)
total_tiles = len(configured_indices)
expected_tiles = self.nrow * self.ncol
if total_tiles <= 1 or total_tiles != expected_tiles or len(self.tile_list) < total_tiles:
return None
# Use the configured grid order from self.index and keep the same reference tile
# location as the original stitch setup.
ref_pos = (self.nrow // 2) * self.ncol + (self.ncol // 2)
if ref_pos >= total_tiles:
return None
selected_positions = tuple(range(total_tiles))
ref_idx = configured_indices[ref_pos]
moving_positions = tuple(pos for pos in selected_positions if pos != ref_pos)
moving_indices = tuple(configured_indices[pos] for pos in moving_positions)
moving_tiles = [self.tile_list[pos] for pos in moving_positions]
return ref_idx, self.tile_list[ref_pos], moving_indices, moving_tiles, selected_positions
def _tile_to_bgr(self, img):
if img.ndim == 2:
return cv2.cvtColor(img, cv2.COLOR_GRAY2BGR)
return img
def _tile_to_gray(self, bgr):
if bgr.ndim == 2:
return bgr
return cv2.cvtColor(bgr, cv2.COLOR_BGR2GRAY)
def _ensure_u8_gray(self, gray):
if gray.dtype == np.uint8:
return gray
return cv2.normalize(gray, None, 0, 255, cv2.NORM_MINMAX).astype(np.uint8)
def _preprocess_gray_for_orb(self, g0, g1):
g0 = cv2.GaussianBlur(g0, (5, 5), 0)
g1 = cv2.GaussianBlur(g1, (5, 5), 0)
g0 = cv2.equalizeHist(g0)
g1 = cv2.equalizeHist(g1)
return g0, g1
def _estimate_bfmatcher_stitch_transform(
self,
t0,
t1,
*,
ransac_reproj_thresh=5.0,
ratio=0.9,
orb_nfeatures=5000,
verbose=True,
):
"""
Estimate a 3x3 transform mapping tile coordinates into the reference tile frame.
"""
t0_bgr = self._tile_to_bgr(t0)
t1_bgr = self._tile_to_bgr(t1)
g0 = self._ensure_u8_gray(self._tile_to_gray(t0_bgr))
g1 = self._ensure_u8_gray(self._tile_to_gray(t1_bgr))
if verbose:
print(
f"BF stitcher debug: t0 dtype={t0.dtype}, t1 dtype={t1.dtype}, "
f"g0 dtype={g0.dtype}, g0 range=({np.min(g0)}, {np.max(g0)}), "
f"g1 dtype={g1.dtype}, g1 range=({np.min(g1)}, {np.max(g1)})"
)
g0, g1 = self._preprocess_gray_for_orb(g0, g1)
orb = cv2.ORB_create(
nfeatures=orb_nfeatures,
scaleFactor=1.2,
nlevels=8,
edgeThreshold=15,
fastThreshold=5,
)
k0, d0 = orb.detectAndCompute(g0, None)
k1, d1 = orb.detectAndCompute(g1, None)
info = {
"ok": False,
"method": None,
"inliers": 0,
"mean_err": None,
"good_matches": 0,
"k0": k0,
"k1": k1,
"t0_bgr": t0_bgr,
"t1_bgr": t1_bgr,
}
if d0 is None or d1 is None or len(k0) < 4 or len(k1) < 4:
if verbose:
print(
"OpenCV BFMatcher stitcher: not enough features.",
f"k0={0 if k0 is None else len(k0)}",
f"k1={0 if k1 is None else len(k1)}",
f"d0_is_none={d0 is None}",
f"d1_is_none={d1 is None}",
)
return None, info
matches = cv2.BFMatcher(cv2.NORM_HAMMING, crossCheck=False).knnMatch(d0, d1, k=2)
good = []
for m_n in matches:
if len(m_n) != 2:
continue
m, n = m_n
if m.distance < ratio * n.distance:
good.append(m)
info["good_matches"] = len(good)
if verbose:
print(f"BFMatcher good matches: {len(good)}")
if len(good) < 4:
return None, info
pts0 = np.float32([k0[m.queryIdx].pt for m in good]).reshape(-1, 1, 2)
pts1 = np.float32([k1[m.trainIdx].pt for m in good]).reshape(-1, 1, 2)
method = "affine_partial2d"
M, inlier_mask = cv2.estimateAffinePartial2D(
pts1,
pts0,
method=cv2.RANSAC,
ransacReprojThreshold=ransac_reproj_thresh,
)
if M is not None:
H = np.vstack([M, [0, 0, 1]]).astype(np.float64)
else:
method = "homography"
H, inlier_mask = cv2.findHomography(pts1, pts0, cv2.RANSAC, ransac_reproj_thresh)
info["method"] = method
info["inliers"] = int(inlier_mask.sum()) if inlier_mask is not None else 0
if verbose:
print(f"Estimated {method} inliers: {info['inliers']}")
if H is None:
return None, info
if abs(H[2, 2]) > 1e-12:
H = H / H[2, 2]
mean_err = 1e9
if inlier_mask is not None:
inlier_bool = inlier_mask.ravel().astype(bool)
if np.any(inlier_bool):
projected = cv2.perspectiveTransform(pts1[inlier_bool], H)
err = np.linalg.norm(
projected.reshape(-1, 2) - pts0[inlier_bool].reshape(-1, 2),
axis=1,
)
mean_err = float(err.mean()) if err.size else 1e9
info["mean_err"] = mean_err
info["ok"] = True
return H, info
def _translation_from_H_to_ref(self, H):
if H is None:
return 0.0, 0.0
H = np.asarray(H, dtype=np.float64)
if abs(H[2, 2]) > 1e-12:
H = H / H[2, 2]
pt = H @ np.array([[0.0], [0.0], [1.0]], dtype=np.float64)
return float(pt[0, 0]), float(pt[1, 0])
def _tile_weight_map(self, h, w, margin=16):
"""
Linear ramp weight that is 0 at tile edges and 1.0 at margin pixels inward.
Used for feathered blending at tile overlaps.
"""
wy = np.ones(h, dtype=np.float32)
wx = np.ones(w, dtype=np.float32)
m = min(margin, h // 2, w // 2)
if m > 0:
ramp = np.linspace(0.0, 1.0, m + 1, dtype=np.float32)[1:]
wy[:m] = ramp
wy[-m:] = ramp[::-1]
wx[:m] = ramp
wx[-m:] = ramp[::-1]
return wy[:, None] * wx[None, :]
def _blend_tile_inplace(self, blend, wsum, cov, src, weight, y0, x0, scratch=None):
"""Copy non-overlap tiles directly; blend only when this tile touches existing content."""
h, w = src.shape[:2]
H, W = blend.shape[:2]
y0d, x0d = max(0, y0), max(0, x0)
y1d, x1d = min(H, y0 + h), min(W, x0 + w)
if y0d >= y1d or x0d >= x1d:
return
sy0, sx0 = y0d - y0, x0d - x0
sh, sw = y1d - y0d, x1d - x0d
w_patch = weight[sy0 : sy0 + sh, sx0 : sx0 + sw]
blend_patch = blend[y0d:y1d, x0d:x1d]
wsum_patch = wsum[y0d:y1d, x0d:x1d]
cov_patch = cov[y0d:y1d, x0d:x1d]
src_patch = src[sy0 : sy0 + sh, sx0 : sx0 + sw]
if not np.any(cov_patch):
blend_patch[:] = src_patch
wsum_patch[:] = w_patch
elif scratch is not None:
s_src, s_alpha = scratch
sf = s_src[:sh, :sw]
sa = s_alpha[:sh, :sw]
sf[:] = src_patch
np.add(wsum_patch, w_patch, out=wsum_patch)
np.maximum(wsum_patch, 1e-6, out=sa)
np.divide(w_patch, sa, out=sa)
np.subtract(sf, blend_patch, out=sf)
sf[:, :, 0] *= sa
sf[:, :, 1] *= sa
sf[:, :, 2] *= sa
np.add(blend_patch, sf, out=blend_patch)
else:
total = wsum_patch + w_patch
alpha = w_patch / np.maximum(total, 1e-6)
src_patch_f = src_patch.astype(np.float32, copy=False)
blend_patch += (src_patch_f - blend_patch) * alpha[:, :, None]
wsum_patch[:] = total
cov_patch[:] = 1
def _mean_gray_bgr(self, bgr):
ch = cv2.mean(bgr)
return (ch[0] + ch[1] + ch[2]) / 3.0
def _match_bgr_brightness(self, tile_bgr, ref_mean_gray):
delta = int(round(ref_mean_gray - self._mean_gray_bgr(tile_bgr)))
if delta == 0:
return tile_bgr
lut = np.clip(np.arange(256, dtype=np.int16) + delta, 0, 255).astype(np.uint8)
return cv2.LUT(tile_bgr, lut)
def _largest_fully_covered_rect(self, cov):
if cov.size == 0:
return None
mask = cov > 0
if not np.any(mask):
return None
h, w = mask.shape
heights = np.zeros(w, dtype=np.int32)
best_area = 0
best_rect = None
for y in range(h):
heights = np.where(mask[y], heights + 1, 0)
stack = []
for x in range(w + 1):
cur_h = heights[x] if x < w else 0
start = x
while stack and stack[-1][1] > cur_h:
start0, h0 = stack.pop()
area = h0 * (x - start0)
if area > best_area:
best_area = area
best_rect = (y - h0 + 1, y + 1, start0, x)
start = start0
if not stack or stack[-1][1] < cur_h:
stack.append((start, cur_h))
return best_rect
def _compute_final_crop_rect(self, cov):
valid = cov > 0
if not np.any(valid):
return None
ys, xs = np.where(valid)
by0, by1 = int(ys.min()), int(ys.max()) + 1
bx0, bx1 = int(xs.min()), int(xs.max()) + 1
rect2 = self._largest_fully_covered_rect(cov[by0:by1, bx0:bx1])
if rect2 is None:
return by0, by1, bx0, bx1
y0, y1, x0, x1 = rect2
return by0 + y0, by0 + y1, bx0 + x0, bx0 + x1
def _geom_cache_key(self, t_ref_bgr, tiles_bgr_c, pad):
ref_h, ref_w = t_ref_bgr.shape[:2]
shapes = tuple(tb.shape[:2] for tb in tiles_bgr_c)
return ref_h, ref_w, shapes, pad
def _render_feature_tiles(
self,
t_ref_bgr,
tiles_bgr,
H_use_list,
*,
pad=5,
frame_idx=0,
print_every=30,
verbose=False,
match_brightness=False,
canvas_cache=None,
blend=True,
):
"""
Composite multiple tiles into one canvas using translation only, where each tile
origin maps into the reference tile coordinates.
"""
if H_use_list is None:
return None
if canvas_cache is None:
canvas_cache = {}
do_profile = verbose and frame_idx % print_every == 0
t_profile0 = cv2.getTickCount() / cv2.getTickFrequency() if do_profile else 0.0
if t_ref_bgr.ndim == 2:
t_ref_bgr = cv2.cvtColor(t_ref_bgr, cv2.COLOR_GRAY2BGR)
h0c, w0c = t_ref_bgr.shape[:2]
if match_brightness:
ref_mean_gray = self._mean_gray_bgr(t_ref_bgr)
tiles_bgr_c = [
self._match_bgr_brightness(
tb if tb.ndim == 3 else cv2.cvtColor(tb, cv2.COLOR_GRAY2BGR),
ref_mean_gray,
)
for tb in tiles_bgr
]
elif any(tb.ndim == 2 for tb in tiles_bgr):
tiles_bgr_c = [tb if tb.ndim == 3 else cv2.cvtColor(tb, cv2.COLOR_GRAY2BGR) for tb in tiles_bgr]
else:
tiles_bgr_c = tiles_bgr
t_after_brightness = cv2.getTickCount() / cv2.getTickFrequency() if do_profile else 0.0
geom_key = self._geom_cache_key(t_ref_bgr, tiles_bgr_c, pad)
geom_cache_hit = canvas_cache.get("geom_key") == geom_key
if not geom_cache_hit:
ref_corners = np.array([[0, 0], [w0c, 0], [w0c, h0c], [0, h0c]], dtype=np.float64)
pts = [ref_corners]
for tile_bgr, H_use in zip(tiles_bgr_c, H_use_list):
if H_use is None:
continue
hi, wi = tile_bgr.shape[:2]
tx, ty = self._translation_from_H_to_ref(H_use)
pts.append(
np.array(
[[tx, ty], [tx + wi, ty], [tx + wi, ty + hi], [tx, ty + hi]],
dtype=np.float64,
)
)
all_xy = np.concatenate(pts, axis=0)
x_min_f = float(all_xy[:, 0].min()) - pad
y_min_f = float(all_xy[:, 1].min()) - pad
x_max_f = float(all_xy[:, 0].max()) + pad
y_max_f = float(all_xy[:, 1].max()) + pad
out_w = max(1, int(np.ceil(x_max_f - x_min_f)))
out_h = max(1, int(np.ceil(y_max_f - y_min_f)))
ref_y0 = int(np.floor(-y_min_f))
ref_x0 = int(np.floor(-x_min_f))
pastes = []
for H_use in H_use_list:
if H_use is None:
pastes.append(None)
continue
tx, ty = self._translation_from_H_to_ref(H_use)
pastes.append((int(np.floor(ty - y_min_f)), int(np.floor(tx - x_min_f))))
_dr_y0 = max(0, ref_y0)
_dr_x0 = max(0, ref_x0)
_dr_y1 = min(out_h, ref_y0 + h0c)
_dr_x1 = min(out_w, ref_x0 + w0c)
for _tb, _pa in zip(tiles_bgr_c, pastes):
if _pa is None:
continue
_py, _px = _pa
_th, _tw = _tb.shape[:2]
_dr_y0 = min(_dr_y0, max(0, _py))
_dr_x0 = min(_dr_x0, max(0, _px))
_dr_y1 = max(_dr_y1, min(out_h, _py + _th))
_dr_x1 = max(_dr_x1, min(out_w, _px + _tw))
canvas_cache["geom_key"] = geom_key
canvas_cache["out_w"] = out_w
canvas_cache["out_h"] = out_h
canvas_cache["ref_y0"] = ref_y0
canvas_cache["ref_x0"] = ref_x0
canvas_cache["pastes"] = pastes
canvas_cache["x_min_f"] = x_min_f
canvas_cache["y_min_f"] = y_min_f
canvas_cache["crop_rect"] = None
canvas_cache["dirty_rect"] = (_dr_y0, _dr_y1, _dr_x0, _dr_x1)
canvas_cache["blend_buf"] = np.zeros((out_h, out_w, 3), dtype=np.float32)
canvas_cache["wsum_buf"] = np.zeros((out_h, out_w), dtype=np.float32)
canvas_cache["cov_buf"] = np.zeros((out_h, out_w), dtype=np.uint8)
canvas_cache["weight_maps"] = {}
else:
out_w = canvas_cache["out_w"]
out_h = canvas_cache["out_h"]
ref_y0 = canvas_cache["ref_y0"]
ref_x0 = canvas_cache["ref_x0"]
pastes = canvas_cache["pastes"]
t_after_geom = cv2.getTickCount() / cv2.getTickFrequency() if do_profile else 0.0
blend_buf = canvas_cache["blend_buf"]
wsum = canvas_cache["wsum_buf"]
cov = canvas_cache["cov_buf"]
weight_maps = canvas_cache["weight_maps"]
if geom_cache_hit:
_dr = canvas_cache.get("dirty_rect")
if _dr is not None:
_dy0, _dy1, _dx0, _dx1 = _dr
blend_buf[_dy0:_dy1, _dx0:_dx1] = 0
wsum[_dy0:_dy1, _dx0:_dx1] = 0
cov[_dy0:_dy1, _dx0:_dx1] = 0
else:
blend_buf.fill(0)
wsum.fill(0)
cov.fill(0)
t_after_reset = cv2.getTickCount() / cv2.getTickFrequency() if do_profile else 0.0
blend_margin = 16 if blend else 0
max_th = max(h0c, *(tb.shape[0] for tb in tiles_bgr_c)) if tiles_bgr_c else h0c
max_tw = max(w0c, *(tb.shape[1] for tb in tiles_bgr_c)) if tiles_bgr_c else w0c
_ss = canvas_cache.get("scratch_src")
_sa = canvas_cache.get("scratch_alpha")
if _ss is None or _ss.shape[0] < max_th or _ss.shape[1] < max_tw:
_ss = np.empty((max_th, max_tw, 3), dtype=np.float32)
canvas_cache["scratch_src"] = _ss
if _sa is None or _sa.shape[0] < max_th or _sa.shape[1] < max_tw:
_sa = np.empty((max_th, max_tw), dtype=np.float32)
canvas_cache["scratch_alpha"] = _sa
_scratch = (_ss, _sa)
blended_tiles = 0
for tile_bgr, H_use, paste in zip(tiles_bgr_c, H_use_list, pastes):
if H_use is None or paste is None:
continue
y0, x0 = paste
th, tw = tile_bgr.shape[:2]
wkey = (th, tw, blend_margin)
if wkey not in weight_maps:
weight_maps[wkey] = self._tile_weight_map(th, tw, blend_margin)
self._blend_tile_inplace(blend_buf, wsum, cov, tile_bgr, weight_maps[wkey], y0, x0, _scratch)
blended_tiles += 1
ref_wkey = (h0c, w0c, blend_margin)
if ref_wkey not in weight_maps:
weight_maps[ref_wkey] = self._tile_weight_map(h0c, w0c, blend_margin)
self._blend_tile_inplace(blend_buf, wsum, cov, t_ref_bgr, weight_maps[ref_wkey], ref_y0, ref_x0, _scratch)
t_after_blend = cv2.getTickCount() / cv2.getTickFrequency() if do_profile else 0.0
crop_rect = canvas_cache.get("crop_rect")
if crop_rect is None:
crop_rect = self._compute_final_crop_rect(cov)
canvas_cache["crop_rect"] = crop_rect
if crop_rect is not None:
y0, y1, x0, x1 = crop_rect
roi = blend_buf[y0:y1, x0:x1]
else:
roi = blend_buf
rh, rw = roi.shape[:2]
stitch_buf = canvas_cache.get("stitch_buf")
if stitch_buf is None or stitch_buf.shape[0] != rh or stitch_buf.shape[1] != rw:
stitch_buf = np.empty((rh, rw, 3), dtype=np.uint8)
canvas_cache["stitch_buf"] = stitch_buf
cv2.convertScaleAbs(roi, dst=stitch_buf)
stitched = stitch_buf
t_after_finalize = cv2.getTickCount() / cv2.getTickFrequency() if do_profile else 0.0
if do_profile:
xmf = canvas_cache.get("x_min_f", 0.0)
ymf = canvas_cache.get("y_min_f", 0.0)
print(
f"stitch_feature_optimized: canvas out_w={out_w}, out_h={out_h}, "
f"x_min={xmf:.2f}, y_min={ymf:.2f}"
)
print(
"stitch_feature_optimized steps: "
f"brightness={t_after_brightness - t_profile0:.6f}s, "
f"geom={t_after_geom - t_after_brightness:.6f}s ({'hit' if geom_cache_hit else 'miss'}), "
f"reset={t_after_reset - t_after_geom:.6f}s, "
f"blend={t_after_blend - t_after_reset:.6f}s ({blended_tiles + 1} tiles incl ref), "
f"finalize={t_after_finalize - t_after_blend:.6f}s, "
f"total={t_after_finalize - t_profile0:.6f}s"
)
return stitched
def find_stitch_boxes(self,img_src,show = False):
img_corr = self.__correct_edge_bloom(img_src)
self.__detect_nonblack_regions(img_corr,show = show, row_tol = self.row_tol)
return len(self.boxes), self.boxes
# return self.boxes
def _copy_into_tile_buffer(self, src_view, dst, flip_x=True, flip_y=True):
if flip_x and flip_y:
cv2.flip(src_view, -1, dst)
elif flip_x:
cv2.flip(src_view, 1, dst)
elif flip_y:
cv2.flip(src_view, 0, dst)
else:
np.copyto(dst, src_view)
def get_stitch_unit(self, img, flip_x=True, flip_y=True,index = np.arange(15)):
"""
Extract each tile given by boxes (x0,y0,x1,y1), default flip both X and Y due to inverting lens.
- img: source image (use corrected image if you prefer)
- boxes: list of (x0,y0,x1,y1)
- flip_x, flip_y: booleans (performed sequentially: X then Y)
- overlay_original: if True paste onto original image copy, otherwise onto blank background
- bg_color: background color for blank canvas (B,G,R)
Returns: canvas image and list of flipped tiles as (x0,y0,flipped_tile)
"""
h, w = img.shape[:2]
active_index = index if self.units is None else self.index
if isinstance(active_index, int):
selected_index = {active_index}
else:
selected_index = set(active_index)
flipped_units = [] if self.units is None else self.units
for i, (x0, y0, x1, y1) in enumerate(self.boxes):
if i not in selected_index:
continue
x0 = max(0, int(x0)); y0 = max(0, int(y0))
x1 = min(w, int(x1)); y1 = min(h, int(y1))
if x1 <= x0 or y1 <= y0:
continue
src_view = img[y0:y1, x0:x1]
if self.units is None:
tile = np.empty_like(src_view)
self._copy_into_tile_buffer(src_view, tile, flip_x=flip_x, flip_y=flip_y)
flipped_units.append((x0, y0, tile))
else:
_, _, tile = flipped_units[i]
if tile.shape != src_view.shape or tile.dtype != src_view.dtype:
tile = np.empty_like(src_view)
self._copy_into_tile_buffer(src_view, tile, flip_x=flip_x, flip_y=flip_y)
flipped_units[i] = (x0, y0, tile)
self.units = flipped_units
return True
def extract_tiles(self):
if not self.isstitch:
# tile_idx = self.__get_tile_index_by_position(self.pos_default[7][0], self.pos_default[7][1])
tile_idx = 7
# if tile_idx is None:
# tile_idx = 7
# Ensure index is always iterable (list or array)
self.index = [tile_idx] if isinstance(tile_idx, int) else tile_idx
self.ncol = 1
self.nrow = 1
tile_list = self.__get_tile_by_index(self.index)
self.tile_list = tile_list
return tile_list
# def stitch_cal(self):
# # init
# tile_list = self.tile_list
# img_stitched_height = None
# stitch_calibration = []
# # Flip col and row for porting
# nrow, ncol = self.ncol, self.nrow
# if not self.isstitch:
# return self.tile_list[0], None
# for i in range(ncol):
# img_stitched_width = None
# for j in range(nrow):
# if j == 0:
# img_j0 = tile_list[i*ncol]
# img_stitched_width = img_j0
# else:
# img_1 = tile_list[i*ncol + j-1]
# img_2 = tile_list[i*ncol + j]
# ov_pos, ov1, ov2, c_corr = self.__get_ov(img_1.astype(np.float32), img_2.astype(np.float32), dim=1)
# stitch_calibration.append(["hor {}".format(j-1),ov_pos])
# # stitch images with stacking
# img_stitched_width = self.__stitch_optimized(img_stitched_width, img_2, ov_pos, ov1, ov2, blend=True, dim=1)
# if i == 0:
# img_stitched_height = img_stitched_width
# stitch_calibration.append(["ver {}".format(i),0])
# pass
# else:
# width = img_stitched_height.shape[1]
# width_new = img_stitched_width.shape[1]
# wdiff = width - width_new
# if wdiff > 0:
# img_stitched_width = np.hstack((img_stitched_width, img_stitched_width[:, -wdiff:]))
# elif wdiff < 0:
# img_stitched_width = img_stitched_width[:, :wdiff]
# ov_pos_h, ov_h1, ov_h2, c_corr = self.__get_ov(img_stitched_height, img_stitched_width, dim=0)
# stitch_calibration.append(["ver {}".format(i),ov_pos_h])
# img_stitched_height = self.__stitch_optimized(img_stitched_height, img_stitched_width, ov_pos_h, ov_h1, ov_h2, blend=True, dim=0)
# self.stitch_calibration = stitch_calibration
# return img_stitched_height, stitch_calibration
# def __stitch_optimized(self, img1, img2, ov_pos, ov1, ov2, blend=True, dim=1):
# _dim = len(img1.shape)
# # Clamp overlap for safety
# if dim == 1:
# ov_pos = int(max(0, min(ov_pos, img1.shape[1], img2.shape[1])))
# else:
# ov_pos = int(max(0, min(ov_pos, img1.shape[0], img2.shape[0])))
# # Fast blend path with cached coefficient tensors
# if not blend or ov_pos <= 1:
# ov = ov1
# else:
# blend_coef = self._get_blend_coef(ov_pos, dim, _dim)
# ov = (
# ov1.astype(np.float32, copy=False) * blend_coef
# + ov2.astype(np.float32, copy=False) * (1.0 - blend_coef)
# ).astype(np.uint8)
# # Build stitched output with one target allocation and slice writes
# if dim == 1:
# left_w = img1.shape[1] - ov_pos
# right_w = img2.shape[1] - ov_pos
# out_w = left_w + ov_pos + right_w
# if _dim == 3:
# stitched_img = np.empty((img1.shape[0], out_w, img1.shape[2]), dtype=img1.dtype)
# if left_w > 0:
# stitched_img[:, :left_w, :] = img1[:, :left_w, :]
# if ov_pos > 0:
# stitched_img[:, left_w:left_w + ov_pos, :] = ov
# if right_w > 0:
# stitched_img[:, left_w + ov_pos:, :] = img2[:, ov_pos:, :]
# else:
# stitched_img = np.empty((img1.shape[0], out_w), dtype=img1.dtype)
# if left_w > 0:
# stitched_img[:, :left_w] = img1[:, :left_w]
# if ov_pos > 0:
# stitched_img[:, left_w:left_w + ov_pos] = ov
# if right_w > 0:
# stitched_img[:, left_w + ov_pos:] = img2[:, ov_pos:]
# else:
# top_h = img1.shape[0] - ov_pos
# bottom_h = img2.shape[0] - ov_pos
# out_h = top_h + ov_pos + bottom_h
# if _dim == 3:
# stitched_img = np.empty((out_h, img1.shape[1], img1.shape[2]), dtype=img1.dtype)
# if top_h > 0:
# stitched_img[:top_h, :, :] = img1[:top_h, :, :]
# if ov_pos > 0:
# stitched_img[top_h:top_h + ov_pos, :, :] = ov
# if bottom_h > 0:
# stitched_img[top_h + ov_pos:, :, :] = img2[ov_pos:, :, :]
# else:
# stitched_img = np.empty((out_h, img1.shape[1]), dtype=img1.dtype)
# if top_h > 0:
# stitched_img[:top_h, :] = img1[:top_h, :]
# if ov_pos > 0:
# stitched_img[top_h:top_h + ov_pos, :] = ov
# if bottom_h > 0:
# stitched_img[top_h + ov_pos:, :] = img2[ov_pos:, :]
# return stitched_img
# def __get_ov(self, img1, img2, dim=1):
# '''
# default dimension is along axis 1 (width of the images)
# '''
# # pass parameters
# nominal_ov = self.nominal_ov_pos
# bound_ov = self.bound
# cross_corr = []
# h1, w1 = img1.shape[:2]
# h2, w2 = img2.shape[:2]
# # clamp tested overlap to valid range (1..min dimension)
# max_possible = w1 if dim == 1 else h1
# max_possible = min(max_possible, w2 if dim == 1 else h2)
# lo = max(1, nominal_ov - bound_ov)
# hi = min(max_possible, nominal_ov + bound_ov)
# ov_space = range(lo, hi + 1)
# for ov in ov_space:
# if dim == 1:
# ov_area1 = img1[:, max(0, w1 - ov):, :]
# ov_area2 = img2[:, :min(ov, w2), :]
# elif dim == 0:
# ov_area1 = img1[max(0, h1 - ov):, :, :]
# ov_area2 = img2[:min(ov, h2), :, :]
# # require exact shape match (detect_nonblack_regions guarantees uniform tile size)
# if ov_area1.size == 0 or ov_area2.size == 0 or ov_area1.shape != ov_area2.shape:
# cross_corr.append(-1.0)
# continue
# # multi-channel cross correlation (average over channels)
# corr = 0.0
# for i in range(min(3, ov_area1.shape[2])):
# a = ov_area1[:, :, i].astype(np.float32)
# b = ov_area2[:, :, i].astype(np.float32)
# denom = np.sqrt(np.sum(a * a) * np.sum(b * b)) + 1e-12
# corr += float(np.sum(a * b) / denom)
# corr = corr / float(min(3, ov_area1.shape[2]))
# cross_corr.append(corr)
# # pick best overlap (ignore invalid entries)
# best_idx = int(np.argmax(cross_corr))
# ov_pos = list(ov_space)[best_idx]
# # extract the overlap regions (assume shapes match)
# if dim == 1:
# ov_1 = img1[:, max(0, w1 - ov_pos):, :].copy()
# ov_2 = img2[:, :min(ov_pos, w2), :].copy()
# else:
# ov_1 = img1[max(0, h1 - ov_pos):, :, :].copy()
# ov_2 = img2[:min(ov_pos, h2), :, :].copy()
# return ov_pos, ov_1, ov_2, cross_corr
# Helper functions for stitching
def __get_tile_index_by_position(self, x, y, tol=20):
"""
Find flipped tile whose top-left matches (x,y) within tol pixels.
flipped_units: list of (x,y,tile)
"""
i= 0
for xi, yi, tile in self.units:
if abs(int(x) - int(xi)) <= tol and abs(int(y) - int(yi)) <= tol:
# return tile
return i
i += 1
return None
def __get_tile_by_index(self, idx):
"""
Retrieve tile by index
"""
if isinstance(idx, int):
idx = [idx]
if len(idx) > len(self.units):
raise ValueError("Index exceeds number of tiles.")
tile_list = []
for i in range(len(idx)):
[xi, yi, tile] = self.units[idx[i]]
tile_list.append(tile)
return tile_list
def __correct_edge_bloom(self, img, method="divide", kernel_size=None, clip=True):
"""
Simple illumination correction to reduce edge bloom / vignetting. Only for getting tile boxes.
- method: "divide" (default) or "subtract"
* divide: img_corrected = (img / (bg + eps)) * gain -- preserves colors
* subtract: img_corrected = img - (bg - mean_bg) -- removes low-freq background
- kernel_size: size for large-kernel blur used as background estimate (odd int).
If None, chosen from image size.
Returns corrected uint8 image.
"""
if img is None:
raise ValueError("Input image is None.")
h, w = img.shape[:2]
if kernel_size is None:
# choose large kernel relative to image size, ensure odd
k = max(31, min(h, w) // 2)
if k % 2 == 0:
k += 1
kernel_size = k
# convert to float32 for stable ops
img_f = img.astype(np.float32)
# estimate background by large Gaussian blur (works well for smooth bloom)
bg = cv2.GaussianBlur(img_f, (kernel_size, kernel_size), 0)
if method == "subtract":
# remove low-frequency background but keep overall brightness
mean_bg = bg.mean(axis=(0, 1), keepdims=True)
corr = img_f - (bg - mean_bg)
else:
# divide: normalized gain correction
eps = 1e-6
# compute gain so that mid-level stays near 128
mean_bg = bg.mean(axis=(0, 1), keepdims=True) + eps
gain = (mean_bg * 0.5) # target scale; 0.5 keeps values reasonable
corr = (img_f / (bg + eps)) * gain
if clip:
corr = np.clip(corr, 0, 255).astype(np.uint8)
else:
corr = corr.astype(np.uint8)
return corr
def __get_unit_pos(self,idx):
if isinstance(idx, int):
idx = [idx]
if len(idx) > len(self.units):
raise ValueError("Index exceeds number of vision units.")
pos_list = []
for i in range(len(idx)):
[xi, yi, tile] = self.units[idx[i]]
pos_list.append((xi, yi))
return pos_list
# Computation Functions
def __detect_nonblack_regions(self, img, morph_k=3, n_boxes_target=15, bk_thresh_step=10, bk_thresh_max=100,show = False, row_tol = 0.4):
"""
Return binary mask of non-black regions and list of bounding boxes (x,y,w,h).
Uses adaptive thresholding on grayscale + small morphology to be robust to illumination.
New behavior: after finding candidate boxes, center-crop all boxes to the same
width/height (smallest found) so returned boxes share a common size.
"""
if img is None:
raise ValueError("Input image is None.")
h, w = img.shape[:2]
n_boxes = 0
bk_thresh = 0 # initial black threshold
bk_thresh_step = 5
bk_thresh_max = 150
# Also include a low global V threshold to capture colored but dark tiles
hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
v = hsv[:,:,2]
ww = hh = 0
while n_boxes != n_boxes_target and bk_thresh <= bk_thresh_max:
_, v_mask = cv2.threshold(v, bk_thresh, 255, cv2.THRESH_BINARY) # tune 50 if needed
mask = v_mask.copy()
# Exclude left and right boundary (20 pixels each) from detection
edge = 20
if w > edge * 2:
mask[:, :edge] = 0
mask[:, -edge:] = 0
# Morphology: remove small specks, fill small holes
k = max(1, morph_k)
kernel = cv2.getStructuringElement(cv2.MORPH_RECT, (k, k))
mask = cv2.morphologyEx(mask, cv2.MORPH_OPEN, kernel, iterations=1)
mask = cv2.morphologyEx(mask, cv2.MORPH_CLOSE, kernel, iterations=2)
# cv2.imshow("mask", mask)
# cv2.waitKey(0)
# find contours of candidate regions
contours, _ = cv2.findContours(mask, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
boxes = []
for c in contours:
x,y,ww,hh = cv2.boundingRect(c)
boxes.append((x,y,ww,hh))
# filter boxes by size (ignore too small or too large tiles)
boxes = self.__filter_boxes_by_size(boxes, (h, w))
n_boxes = len(boxes)
bk_thresh += bk_thresh_step
print("Detected {} candidate boxes with bk_thresh={}".format(n_boxes, bk_thresh - bk_thresh_step))
if n_boxes == 0:
self.boxes = []
return n_boxes
# compute common center-crop size: use minimum width/height among boxes
widths = [b[2] for b in boxes]
heights = [b[3] for b in boxes]
# target_w = max(1,int(min(widths)))
# target_h = max(1,int(min(heights)))
target_w = self.box_size[0]
target_h = self.box_size[1]
# center-crop each box to (target_w, target_h) inside original box bounds
cropped_boxes = []
for (x, y, ww, hh) in boxes:
cx = x + ww // 2
cy = y + hh // 2
nx0 = int(cx - target_w // 2)
ny0 = int(cy - target_h // 2)
# clamp to image bounds
nx0 = max(0, min(nx0, w - target_w))
ny0 = max(0, min(ny0, h - target_h))
# Convert to (x0, y0, x1, y1) format for direct image region retrieval
nx1 = nx0 + target_w
ny1 = ny0 + target_h
cropped_boxes.append((nx0, ny0, nx1, ny1))
# sort boxes left-to-right, top-to-bottom (useful for grid)
# Use quantized y-coordinates to group boxes into rows, making sorting robust to noise
if len(cropped_boxes) > 0:
# Calculate row tolerance based on typical box height (use median height)
heights = [b[3] - b[1] for b in cropped_boxes]
median_height = np.median(heights) if heights else target_h
# Use a fraction of the box height as tolerance (e.g., 20% of box height)
row_tolerance = max(1, int(median_height * row_tol))
# Quantize y-coordinates to group boxes into rows
def get_row_key(box):
y = box[1] # y0 coordinate
# Round y to nearest multiple of row_tolerance to group into rows
quantized_y = (y // row_tolerance) * row_tolerance
return (quantized_y, box[0]) # Sort by quantized row, then by x
cropped_boxes = sorted(cropped_boxes, key=get_row_key)
else:
cropped_boxes = sorted(cropped_boxes, key=lambda b: (b[1], b[0]))
self.boxes = cropped_boxes
img_with_boxes = self.draw_boxes(img= img)
if show:
cv2.imshow("Detected Boxes", img_with_boxes)
cv2.waitKey(0)
img_path = "./config/compound_eye.png"
if os.path.exists(img_path):
cv2.imwrite(img_path, img_with_boxes)
else:
os.makedirs(os.path.dirname(img_path), exist_ok=True)
cv2.imwrite(img_path, img_with_boxes)
# print("Check if compound eye detection image valid: {}".format(img_path))
return cropped_boxes
def draw_boxes(self, img, thickness=2):
"""
Draw bounding boxes on the image.
- img: input image (will be copied, not modified in-place)
- thickness: line thickness
Returns: image with drawn boxes
"""
if self.boxes is None or len(self.boxes) == 0:
print("No boxes to draw")
return img
img_draw = img.copy()
color=(0, 255, 0)
for i, (x0, y0, x1, y1) in enumerate(self.boxes):
# Draw rectangle
cv2.rectangle(img_draw, (x0, y0), (x1, y1), color, thickness)
# Draw index
text_size = cv2.getTextSize(str(i), cv2.FONT_HERSHEY_SIMPLEX, 0.6, 2)[0]
text_pos = (x0 + 5, y0 + text_size[1] + 5)
# Draw text background and text
cv2.rectangle(img_draw, (text_pos[0] - 2, text_pos[1] - text_size[1] - 2),
(text_pos[0] + text_size[0] + 2, text_pos[1] + 2), (0, 0, 0), -1)
cv2.putText(img_draw, str(i), text_pos, cv2.FONT_HERSHEY_SIMPLEX, 0.6, color, 2)
return img_draw
def __filter_boxes_by_size(self, boxes, img_shape):
"""
Remove boxes that are too small or too large relative to the image.
- boxes: list of (x,y,w,h)
- img_shape: (height, width)
- min_area_frac / max_area_frac: allowed area fraction of image
Returns filtered list of boxes.
"""
h, w = img_shape
img_area = h * w
min_area = img_area * float(self.min_area_frac)
max_area = img_area * float(self.max_area_frac)
filtered = []
for (x,y,ww,hh) in boxes:
area = ww * hh
if area < min_area or area > max_area or (abs(ww - hh) > self.max_aspect_ratio):
continue
filtered.append((x,y,ww,hh))
return filtered