#!/usr/bin/env python3
"""Regenerates the JPEG fixtures used by tests/decode.rs.

Run from the repository root:  python3 tests/data/generate.py

Each fixture is a solid colour so the test can assert exact sample values
after decoding. Green is deliberate: it is the colour the ATEM keys on, and a
wrong YUV matrix or range shows up here before it shows up on stage.
"""
from PIL import Image
import pathlib

OUT = pathlib.Path(__file__).parent
W, H = 64, 32
GREEN = (0, 255, 0)

# PIL subsampling codes: 0 = 4:4:4, 1 = 4:2:2, 2 = 4:2:0
for name, subs in [("green-444.jpg", 0), ("green-422.jpg", 1), ("green-420.jpg", 2)]:
    Image.new("RGB", (W, H), GREEN).save(OUT / name, "JPEG", quality=95, subsampling=subs)

Image.new("L", (W, H), 128).save(OUT / "gray.jpg", "JPEG", quality=95)

for p in sorted(OUT.glob("*.jpg")):
    print(f"{p.name}: {p.stat().st_size} bytes")