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Tests / Test apps.device-host-agent.tests.test_e2e.test_public_sdk_reports_fake_device_success_and_runtime_failure failed
feat(perception): sample OCR text foreground/background colors
PaddleOCR itself returns no color info, only text/bounds/confidence.
Add pixel-level post-processing in perception/ocr.py: crop the
screenshot to each OCR box, split pixels into two luminance clusters
via Otsu threshold, and treat the minority cluster as the text stroke
(foreground) and the majority as the background. New
SceneElement.foreground_color/background_color fields ("#rrggbb",
None when not OCR-sourced or sampling fails) round-trip through
to_dict/from_dict alongside the existing accessibility-state fields.
Planner system prompt documents the new fields as a secondary signal.

pillow is promoted from an implicit paddleocr transitive dependency to
an explicit direct dependency since perception/ocr.py now imports PIL
directly; uv.lock re-resolved with no version change (already locked
at 12.3.0).
2026-07-15 20:58:47 +08:00

328 lines
10 KiB
Python

from __future__ import annotations
import os
import tempfile
import logging
from collections.abc import Iterable
from dataclasses import dataclass, replace
from numbers import Real
from pathlib import Path
from typing import Any
from core.models import Bounds, SceneElement
logger = logging.getLogger(__name__)
@dataclass(frozen=True)
class OCRBox:
text: str
bounds: Bounds
confidence: float | None = None
foreground_color: str | None = None
background_color: str | None = None
def to_scene_element(self, element_id: str) -> SceneElement:
return SceneElement(
id=element_id,
type="text",
text=self.text,
bounds=self.bounds,
confidence=self.confidence,
source="ocr",
foreground_color=self.foreground_color,
background_color=self.background_color,
)
class PaddleOCREngine:
def __init__(self, **kwargs: Any) -> None:
# Device screenshots are already upright, flat digital captures, not
# photographed paper documents, so PaddleOCR's document-preprocessing
# models (orientation classification + UVDoc unwarping) have nothing
# real to correct. Left at their library defaults (True), they still
# run, geometrically warp the image, and detect/recognize text against
# that warped image, returning box coordinates that no longer line up
# with the original screenshot. Callers can still opt back in via an
# explicit kwarg.
kwargs.setdefault("use_doc_orientation_classify", False)
kwargs.setdefault("use_doc_unwarping", False)
self.kwargs = kwargs
self._engine: Any | None = None
def extract(self, image: bytes | str | Path) -> list[OCRBox]:
engine = self._load()
image_input, temp_path = _image_input(image)
try:
if hasattr(engine, "predict"):
raw = engine.predict(input=image_input)
else:
raw = engine.ocr(image_input, cls=True)
boxes = parse_paddle_result(raw)
return _with_sampled_colors(boxes, image_input)
finally:
if temp_path:
temp_path.unlink(missing_ok=True)
def _load(self) -> Any:
if self._engine is None:
from paddleocr import PaddleOCR
self._engine = PaddleOCR(**self.kwargs)
return self._engine
def run_ocr(
image: bytes | str | Path,
*,
engine: PaddleOCREngine | None = None,
strict: bool = False,
) -> list[SceneElement]:
try:
boxes = (engine or PaddleOCREngine()).extract(image)
except Exception:
if strict:
raise
logger.warning("OCR extraction failed; continuing without OCR", exc_info=True)
return []
return [box.to_scene_element(f"ocr-{index:03d}") for index, box in enumerate(boxes)]
def _with_sampled_colors(boxes: list[OCRBox], image_path: str) -> list[OCRBox]:
if not boxes:
return boxes
try:
from PIL import Image
with Image.open(image_path) as source:
picture = source.convert("RGB")
sampled = []
for box in boxes:
foreground, background = _estimate_colors(picture, box.bounds)
sampled.append(
replace(
box,
foreground_color=foreground,
background_color=background,
)
)
return sampled
except Exception:
logger.warning(
"OCR color sampling failed; continuing without foreground/background colors",
exc_info=True,
)
return boxes
def _estimate_colors(picture: Any, bounds: Bounds) -> tuple[str | None, str | None]:
left = max(0, int(bounds.x))
top = max(0, int(bounds.y))
right = min(picture.width, int(round(bounds.right)))
bottom = min(picture.height, int(round(bounds.bottom)))
if right - left < 2 or bottom - top < 2:
return (None, None)
pixels = list(picture.crop((left, top, right, bottom)).get_flattened_data())
threshold = _otsu_threshold(pixels)
if threshold is None:
return (None, None)
dark = [pixel for pixel in pixels if _luminance(pixel) <= threshold]
light = [pixel for pixel in pixels if _luminance(pixel) > threshold]
if not dark or not light:
return (None, None)
# Text strokes normally cover a minority of the box's pixels regardless of
# whether the text is dark-on-light or light-on-dark, so the smaller of
# the two luminance clusters is treated as the foreground (text) color.
foreground, background = (dark, light) if len(dark) <= len(light) else (light, dark)
return _average_hex(foreground), _average_hex(background)
def _luminance(pixel: tuple[int, int, int]) -> float:
r, g, b = pixel
return 0.299 * r + 0.587 * g + 0.114 * b
def _otsu_threshold(pixels: list[tuple[int, int, int]]) -> float | None:
total = len(pixels)
if total == 0:
return None
histogram = [0] * 256
for pixel in pixels:
histogram[int(_luminance(pixel))] += 1
sum_total = sum(level * count for level, count in enumerate(histogram))
sum_background = 0.0
weight_background = 0
best_variance = -1.0
threshold = 0
for level, count in enumerate(histogram):
weight_background += count
if weight_background == 0:
continue
weight_foreground = total - weight_background
if weight_foreground == 0:
break
sum_background += level * count
mean_background = sum_background / weight_background
mean_foreground = (sum_total - sum_background) / weight_foreground
variance = (
weight_background
* weight_foreground
* (mean_background - mean_foreground) ** 2
)
if variance > best_variance:
best_variance = variance
threshold = level
return float(threshold)
def _average_hex(pixels: list[tuple[int, int, int]]) -> str:
count = len(pixels)
r = sum(pixel[0] for pixel in pixels) // count
g = sum(pixel[1] for pixel in pixels) // count
b = sum(pixel[2] for pixel in pixels) // count
return f"#{r:02x}{g:02x}{b:02x}"
def parse_paddle_result(raw: Any) -> list[OCRBox]:
boxes: list[OCRBox] = []
for item in _flatten_pages(raw):
parsed = _parse_line(item)
if parsed:
boxes.append(parsed)
return boxes
def _image_input(image: bytes | str | Path) -> tuple[str, Path | None]:
if isinstance(image, bytes):
handle = tempfile.NamedTemporaryFile(delete=False, suffix=".png")
try:
handle.write(image)
finally:
handle.close()
return handle.name, Path(handle.name)
return os.fspath(image), None
def _flatten_pages(raw: Any) -> Iterable[Any]:
if raw is None:
return []
if isinstance(raw, dict):
return _dict_lines(raw)
if isinstance(raw, list):
flattened: list[Any] = []
for page in raw:
if isinstance(page, dict):
flattened.extend(_dict_lines(page))
elif _looks_like_ocr_line(page):
flattened.append(page)
elif isinstance(page, list):
flattened.extend(page)
return flattened
json_attr = getattr(raw, "json", None)
if callable(json_attr):
return _flatten_pages(json_attr())
if isinstance(json_attr, (dict, list)):
return _flatten_pages(json_attr)
return []
def _dict_lines(data: dict[str, Any]) -> list[Any]:
result = data.get("res")
payload = result if isinstance(result, dict) else data
texts = _first_nonempty(payload, "rec_texts", "texts")
scores = _first_nonempty(payload, "rec_scores", "scores")
boxes = _first_nonempty(payload, "rec_boxes", "rec_polys", "dt_polys")
return [
{
"text": text,
"confidence": scores[index] if index < len(scores) else None,
"points": boxes[index] if index < len(boxes) else None,
}
for index, text in enumerate(texts)
]
def _looks_like_ocr_line(value: Any) -> bool:
return isinstance(value, (list, tuple)) and len(value) >= 2
def _parse_line(line: Any) -> OCRBox | None:
if isinstance(line, dict):
text = line.get("text")
points = _first_nonempty(line, "points", "box", "bounds")
confidence = line.get("confidence")
if not _has_items(text) or not _has_items(points):
return None
return OCRBox(
str(text), _bounds_from_points(points), _float_or_none(confidence)
)
if not _looks_like_ocr_line(line):
return None
points = line[0]
text_payload = line[1]
if isinstance(text_payload, (list, tuple)) and text_payload:
text = text_payload[0]
confidence = text_payload[1] if len(text_payload) > 1 else None
else:
text = text_payload
confidence = None
if not text:
return None
return OCRBox(str(text), _bounds_from_points(points), _float_or_none(confidence))
def _bounds_from_points(points: Any) -> Bounds:
if isinstance(points, dict):
return Bounds.from_dict(points)
if _has_length(points, 4) and all(isinstance(value, Real) for value in points):
x1, y1, x2, y2 = [float(value) for value in points]
return Bounds(x1, y1, x2 - x1, y2 - y1)
xs: list[float] = []
ys: list[float] = []
for point in points:
if isinstance(point, dict):
xs.append(float(point["x"]))
ys.append(float(point["y"]))
else:
xs.append(float(point[0]))
ys.append(float(point[1]))
return Bounds(min(xs), min(ys), max(xs) - min(xs), max(ys) - min(ys))
def _float_or_none(value: Any) -> float | None:
if value is None:
return None
return float(value)
def _first_nonempty(data: dict[str, Any], *keys: str) -> Any:
for key in keys:
value = data.get(key)
if _has_items(value):
return value
return []
def _has_items(value: Any) -> bool:
if value is None:
return False
try:
return len(value) > 0
except TypeError:
return bool(value)
def _has_length(value: Any, length: int) -> bool:
try:
return len(value) == length
except TypeError:
return False