get_vga_frames.py

from aiohttp import web
import aiohttp_cors
from tqdm import tqdm
from PIL import Image
import os

# palette avoids glitchy dithering in gif
# ffmpeg -i frame-%d.png -vf "split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse" output.gif

N_FRAMES = 32
OUT_DIR = "frames"
app = web.Application()

async def receive_file(ws: web.WebSocketResponse) -> tuple[str, bytes]:
  name = await ws.receive_str()
  data = await ws.receive_bytes()
  return name, data

async def websocket_handler(request):
  print("connected")
  ws = web.WebSocketResponse()
  await ws.prepare(request)

  # Ignore first frame
  await receive_file(ws)
  
  for i in tqdm(range(N_FRAMES)):
    _, data = await receive_file(ws)
    img = Image.frombytes("RGBA", (736, 520), data)
    img = img.crop((46, 33, 686, 513))
    img.save(f"{OUT_DIR}/frame-{i}.png")
  
  await ws.close()

  return ws

app.add_routes([web.get('/', websocket_handler)])

cors = aiohttp_cors.setup(app, defaults={
  "*": aiohttp_cors.ResourceOptions(
      allow_credentials=True,
      expose_headers="*",
      allow_headers="*"
  )
})

for route in list(app.router.routes()):
  cors.add(route)

if __name__ == '__main__':
  os.makedirs(OUT_DIR, exist_ok=True)
  web.run_app(app, host="0.0.0.0", port=5000)