changedetection.io/changedetectionio/content_fetchers/screenshot_handler.py

74 wiersze
2.7 KiB
Python

# Pages with a vertical height longer than this will use the 'stitch together' method.
# - Many GPUs have a max texture size of 16384x16384px (or lower on older devices).
# - If a page is taller than ~8000–10000px, it risks exceeding GPU memory limits.
# - This is especially important on headless Chromium, where Playwright may fail to allocate a massive full-page buffer.
from loguru import logger
from changedetectionio.content_fetchers import SCREENSHOT_MAX_HEIGHT_DEFAULT, SCREENSHOT_DEFAULT_QUALITY
def stitch_images_worker(pipe_conn, chunks_bytes, original_page_height, capture_height):
import os
import io
from PIL import Image, ImageDraw, ImageFont
try:
# Load images from byte chunks
images = [Image.open(io.BytesIO(b)) for b in chunks_bytes]
total_height = sum(im.height for im in images)
max_width = max(im.width for im in images)
# Create stitched image
stitched = Image.new('RGB', (max_width, total_height))
y_offset = 0
for im in images:
stitched.paste(im, (0, y_offset))
y_offset += im.height
# Draw caption on top (overlaid, not extending canvas)
draw = ImageDraw.Draw(stitched)
if original_page_height > capture_height:
caption_text = f"WARNING: Screenshot was {original_page_height}px but trimmed to {capture_height}px because it was too long"
padding = 10
font_size = 35
font_color = (255, 0, 0)
background_color = (255, 255, 255)
# Try to load a proper font
try:
font = ImageFont.truetype("arial.ttf", font_size)
except IOError:
font = ImageFont.load_default()
bbox = draw.textbbox((0, 0), caption_text, font=font)
text_width = bbox[2] - bbox[0]
text_height = bbox[3] - bbox[1]
# Draw white rectangle background behind text
rect_top = 0
rect_bottom = text_height + 2 * padding
draw.rectangle([(0, rect_top), (max_width, rect_bottom)], fill=background_color)
# Draw text centered horizontally, 10px padding from top of the rectangle
text_x = (max_width - text_width) // 2
text_y = padding
draw.text((text_x, text_y), caption_text, font=font, fill=font_color)
# Encode and send image
output = io.BytesIO()
stitched.save(output, format="JPEG", quality=int(os.getenv("SCREENSHOT_QUALITY", SCREENSHOT_DEFAULT_QUALITY)))
pipe_conn.send_bytes(output.getvalue())
stitched.close()
except Exception as e:
pipe_conn.send(f"error:{e}")
finally:
pipe_conn.close()