How to add an error dialog pop-up with Claude

Add stacked error dialogs to input.mp4. Each dialog is 80% of the frame width wide and 0.42 times that tall: a light gray (240, 240, 240) box with a dark gray outline and a soft drop shadow, a blue (0, 84, 227) title bar along the top (20% of the dialog's height) reading "Error" in bold white on the left with a small red close button on the right, a red (220, 30, 30) circle with a white X on the left (diameter 30% of the dialog height), the message "Dull skin detected." in black beside it, and a gray "OK" button with a blue outline centered near the bottom. Six dialogs appear one at a time, the first at 0.5 seconds and then one every 0.25 seconds, each scaling from 85% to full size over 0.08 seconds and staying on to the end. The first dialog's top-left corner is at 5% across and 8% down; each next one sits 3% of the width further right and 8.5% of the height further down, drawn on top of the ones before. Use Python with Pillow to draw the dialogs and their text and ffmpeg to put them on the video (don't rely on ffmpeg's drawtext filter), keep the audio, and save it as output.mp4.

#!/usr/bin/env python3
"""Error dialog pop-up: system error boxes with a red X and an OK button stack down the screen one after another.

Usage: python3 error-dialog-popup.py input.mp4 output.mp4
Needs ffmpeg and Pillow (pip install pillow).
"""
import json
import math
import subprocess
import sys
from pathlib import Path

from PIL import Image, ImageDraw, ImageFont

TITLE = "Error"                       # title bar text
MESSAGE = "Dull skin detected."       # message next to the red X
COUNT = 6                             # how many dialogs stack up
START = 0.5                           # second the first dialog appears
EVERY = 0.25                          # seconds between dialogs
WIDTH = 0.80                          # dialog width as a share of the frame width
FIRST = (0.05, 0.08)                  # first dialog's top-left corner (0-1 across and down)
STEP = (0.03, 0.085)                  # how far each next dialog moves right and down
TITLE_BAR = (0, 84, 227)              # title bar blue
X_RED = (220, 30, 30)                 # error icon red
FONTS = ["/System/Library/Fonts/Supplemental/Arial.ttf",          # macOS
         "/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf",       # Linux
         "C:/Windows/Fonts/arial.ttf"]                            # Windows
BOLD_FONTS = ["/System/Library/Fonts/Supplemental/Arial Bold.ttf",  # macOS
              "/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf",  # Linux
              "C:/Windows/Fonts/arialbd.ttf"]                          # Windows
FONT_FILE = next((f for f in FONTS if Path(f).exists()), None) or sys.exit("No font found: add one to FONTS")
BOLD_FILE = next((f for f in BOLD_FONTS if Path(f).exists()), None) or sys.exit("No bold font found: add one to BOLD_FONTS")


def dialog():
    """One error box: blue title bar with a close button, red X icon, message and an OK button."""
    dw = round(w * WIDTH)
    dh = round(dw * 0.42)
    bar = round(dh * 0.20)
    img = Image.new("RGBA", (dw + 6, dh + 6))
    draw = ImageDraw.Draw(img)
    draw.rectangle([6, 6, dw + 5, dh + 5], fill=(0, 0, 0, 90))                       # drop shadow
    draw.rectangle([0, 0, dw - 1, dh - 1], fill=(240, 240, 240), outline=(90, 90, 90))
    draw.rectangle([1, 1, dw - 2, bar], fill=TITLE_BAR)
    title_font = ImageFont.truetype(BOLD_FILE, round(bar * 0.55))
    draw.text((bar * 0.4, bar / 2 + 1), TITLE, font=title_font, anchor="lm", fill="white")
    c = round(bar * 0.78)                                                               # close button
    cx0, cy0 = dw - c - round(bar * 0.15), round((bar - c) / 2) + 1
    draw.rectangle([cx0, cy0, cx0 + c, cy0 + c], fill=(200, 60, 40), outline="white")
    draw.text((cx0 + c / 2, cy0 + c / 2), "x", font=title_font, anchor="mm", fill="white")
    r = round(dh * 0.15)                                                                # red X icon
    ix, iy = round(dw * 0.12), round(bar + (dh - bar) * 0.38)
    draw.ellipse([ix - r, iy - r, ix + r, iy + r], fill=X_RED)
    k = r * 0.42
    for a, b in (((ix - k, iy - k), (ix + k, iy + k)), ((ix - k, iy + k), (ix + k, iy - k))):
        draw.line([a, b], fill="white", width=max(3, r // 4))
    draw.text((ix + r * 1.6, iy), MESSAGE, font=ImageFont.truetype(FONT_FILE, round(dh * 0.13)), anchor="lm", fill="black")
    bw, bh = round(dw * 0.24), round(dh * 0.19)                                        # OK button
    bx, by = (dw - bw) // 2, dh - bh - round(dh * 0.09)
    draw.rectangle([bx, by, bx + bw, by + bh], fill=(225, 225, 225), outline=(0, 120, 215), width=2)
    draw.text((bx + bw / 2, by + bh / 2), "OK", font=ImageFont.truetype(FONT_FILE, round(bh * 0.5)), anchor="mm", fill="black")
    return img


def overlay(t):
    """Every dialog whose time has come, each with a quick 0.08s scale-up as it appears."""
    img = Image.new("RGBA", (w, h))
    for i in range(COUNT):
        age = t - (START + i * EVERY)
        if age < 0:
            break
        scale = 0.85 + 0.15 * min(age / 0.08, 1)
        d = box if scale == 1 else box.resize((round(box.width * scale), round(box.height * scale)), Image.LANCZOS)
        x = w * (FIRST[0] + i * STEP[0]) + (box.width - d.width) / 2
        y = h * (FIRST[1] + i * STEP[1]) + (box.height - d.height) / 2
        img.alpha_composite(d, (round(x), round(y)))
    return img


def probe(path):
    info = json.loads(subprocess.check_output(["ffprobe", "-v", "error", "-select_streams", "v:0", "-show_entries",
                                               "stream=width,height,r_frame_rate:format=duration", "-of", "json", path]))
    s = info["streams"][0]
    num, den = s["r_frame_rate"].split("/")
    return s["width"], s["height"], s["r_frame_rate"], float(num) / float(den), float(info["format"]["duration"])


def render(src, out):
    """Draw overlay(t) on every frame of src and save to out, keeping the audio."""
    ff = subprocess.Popen(["ffmpeg", "-y", "-v", "error", "-i", src,
                           "-f", "rawvideo", "-pix_fmt", "rgba", "-s", f"{w}x{h}", "-r", rate, "-i", "-",
                           "-filter_complex", "[0:v][1:v]overlay=shortest=1,format=yuv420p[v]",
                           "-map", "[v]", "-map", "0:a?", "-c:v", "libx264", "-crf", "18", "-c:a", "copy", out],
                          stdin=subprocess.PIPE)
    for i in range(math.ceil(duration * fps)):
        ff.stdin.write(overlay(i / fps).tobytes())
    ff.stdin.close()
    if ff.wait():
        sys.exit("ffmpeg failed")


src, out = sys.argv[1:3]
w, h, rate, fps, duration = probe(src)
box = dialog()
render(src, out)