index.py

import cv2
import numpy as np
import os
import math
import json

INPUT_IMAGE = "glyph_E4.png"
OUTPUT_DIR = "discord_emojis"
TARGET = 128

os.makedirs(OUTPUT_DIR, exist_ok=True)

# Load image with transparency
img = cv2.imread(INPUT_IMAGE, cv2.IMREAD_UNCHANGED)

# Create grayscale for detection
if img.shape[2] == 4:
    gray = cv2.cvtColor(img, cv2.COLOR_BGRA2GRAY)
else:
    gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)

# Detect glyph pixels
_, thresh = cv2.threshold(gray, 240, 255, cv2.THRESH_BINARY_INV)

contours, _ = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)

boxes = []

for c in contours:
    x, y, w, h = cv2.boundingRect(c)

    # ignore tiny noise
    if w * h < 30:
        continue

    boxes.append((x, y, w, h))

# Sort boxes top-to-bottom then left-to-right
boxes.sort(key=lambda b: (b[1] // 40, b[0]))

emoji_index = 0
mapping = {}

for (x, y, w, h) in boxes:

    glyph = img[y:y+h, x:x+w]

    # integer pixel-art scaling
    scale = TARGET // h
    if scale < 1:
        scale = 1

    new_w = w * scale
    new_h = h * scale

    resized = cv2.resize(
        glyph,
        (new_w, new_h),
        interpolation=cv2.INTER_NEAREST
    )

    tiles = math.ceil(new_w / TARGET)

    base_name = f"glyph_{emoji_index}"
    mapping[base_name] = []

    for t in range(tiles):

        # Transparent canvas
        canvas = np.zeros((TARGET, TARGET, 4), dtype=np.uint8)

        start = t * TARGET
        end = min(start + TARGET, new_w)

        part = resized[:, start:end]

        # Ensure RGBA
        if part.shape[2] == 3:
            part = cv2.cvtColor(part, cv2.COLOR_BGR2BGRA)

        # center vertically
        y_offset = (TARGET - new_h) // 2

        canvas[y_offset:y_offset+new_h, 0:part.shape[1]] = part

        filename = f"{base_name}_{t}.png"
        path = os.path.join(OUTPUT_DIR, filename)

        cv2.imwrite(path, canvas)

        mapping[base_name].append(filename)

    emoji_index += 1

# Save glyph mapping
with open(os.path.join(OUTPUT_DIR, "emoji_map.json"), "w") as f:
    json.dump(mapping, f, indent=4)

print("Discord emoji pack exported successfully.")