diff --git a/chat_to_subtitle.py b/chat_to_subtitle.py
new file mode 100644
index 0000000..a2f9c13
--- /dev/null
+++ b/chat_to_subtitle.py
@@ -0,0 +1,74 @@
+
+import json
+import sys
+
+import argh
+
+CHAT_BOX = (1220, 100, 1910, 810)
+
+def encode_time(time):
+	hours, time = divmod(time, 3600)
+	mins, secs = divmod(time, 60)
+	return f"{int(hours)}:{int(mins):02d}:{secs:05.2f}"
+
+def encode_dialogue(start, end, text):
+	return f"Dialogue: {encode_time(start)}, {encode_time(end)}, Chat, {text}"
+
+def message_to_line(message, time_base):
+	time = message["time"] - time_base
+	tags = message.get("tags", {})
+
+	sender = tags.get("display-name")
+	if sender is None:
+		sender = message["sender"]
+
+	content = message["params"][1]
+	if content.startswith("\x01"):
+		content = content[1:-1].split(" ", 1)[1]
+		text = f"{sender} {content}"
+	else:
+		text = f"{sender}: {content}"
+
+	color = tags.get("color")
+	if color is None:
+		color = "FFFFFF"
+	else:
+		color = color.lstrip("#")
+	text = f"{{ \\c&H{color}& }}" + text
+	return time, text
+
+def lines_to_dialogue(start, end, lines):
+	lines = "\\N".join([text for start, text in lines][::-1])
+	clip_args = ",".join(map(str, CHAT_BOX))
+	text = f"{{ \\clip({clip_args}) }}" + lines
+	return encode_dialogue(start, end, text)
+
+def gen_dialogues(messages, time_base, message_ttl=10):
+	window = []
+	prev_start = None
+	for message in messages:
+		next_start, text = message_to_line(message, time_base)
+		while window and window[0][0] + message_ttl < next_start:
+			end = window[0][0] + message_ttl
+			yield lines_to_dialogue(prev_start, end, window)
+			window.pop(0)
+			prev_start = end
+		window.append((next_start, text))
+		if prev_start is not None:
+			yield lines_to_dialogue(prev_start, next_start, window)
+		prev_start = next_start
+	# flush remaining messages
+	while window:
+		end = window[0][0] + message_ttl
+		yield lines_to_dialogue(prev_start, end, window)
+		window.pop(0)
+		prev_start = end
+
+def main(time_base=0):
+	messages = sys.stdin.read().strip().split("\n")
+	messages = [json.loads(line) for line in messages]
+	for dialogue in gen_dialogues(messages, time_base):
+		print(dialogue)
+
+if __name__ == '__main__':
+	argh.dispatch_command(main)