--- title: "How to add a stretchy text with Claude (tested prompt and script)" description: "White letters shoot up tall and thin, squash flat on landing and spring into the words \"SKIN BOUNCE\", then squash and stretch up off the screen. Install one skill and ask Claude Code, or run the Python script we tested yourself." url: https://www.recharm.com/effects/stretchy-text --- # How to add a stretchy text with Claude White letters shoot up tall and thin, squash flat on landing and spring into the words "SKIN BOUNCE", then squash and stretch up off the screen. Made by the script on this page, from our own test clip. ## Get this effect 1. ### Switch to Code in your [Claude Desktop App](https://claude.com/download) 2. ### Install the skill (once) ``` Install the Recharm video effects skill: download https://recharm-growth-staging.s3.us-east-2.amazonaws.com/website/downloads/recharm-video-effects.zip and unzip it into ~/.claude/skills ``` 3. ### Ask for the effect ``` Add a stretchy text to input.mp4 Lines: [("SKIN", 0.4, 0.17), ("BOUNCE", 0.8, 0.275)] Land, leave: see the recipe ``` ## Several videos, several effects, one ask Put your clips in the folder, mention them with @, and ask for everything at once. Claude runs one tested script after another on each clip, then joins them. Add a stretchy text to **@clip1.mp4**, put a sale badge on **@clip2.mp4**, give **@clip3.mp4** a VHS look, then join all three with crossfades. ## Settings you can change Ask Claude to change any of these, or edit them at the top of the script. | Setting | Default | What it does | | ------------- | ----------------------------------------------- | ----------------------------------------------------------------------------------------------- | | `LINES` | `[("SKIN", 0.4, 0.17), ("BOUNCE", 0.8, 0.275)]` | Each word, the second its first letter lands and where its baseline sits (0 = top, 1 = bottom). | | `STAGGER` | `0.05` | Seconds between one letter and the next. | | `IN` | `0.5` | Seconds a letter takes to land and settle. | | `OUT_START` | `3.2` | Second the letters start to leave. | | `OUT` | `0.4` | Seconds a letter takes to leave. | | `WIDTH` | `0.8` | The longest word's width as a share of the frame width. | | `COLOR` | `(255, 255, 255)` | Letter color. | | `OUTLINE` | `0.015` | Outline thickness as a share of the frame width. | | `LAND, LEAVE` | `see the recipe` | Keyframes of (time 0-1, width scale, height scale) for a letter landing and leaving. | ## Without the skill Don’t want to install the skill? Paste this prompt into Claude Code and Claude writes the script itself. ``` Add stretchy text to input.mp4: two lines in white (255, 255, 255) Arial Black with a dark purple (40, 12, 60) outline 1.5% of the frame width thick, centered horizontally. "SKIN" sits with its baseline 17% of the way down and "BOUNCE" with its baseline 27.5% down; the font size makes "BOUNCE" 80% of the frame width wide, and "SKIN" uses the same size. Animate each letter on its own, scaled from its bottom center on the baseline: the first letter of SKIN starts at 0.4 seconds and the first of BOUNCE at 0.8 seconds, each next letter 0.05 seconds after the one before. A letter takes 0.5 seconds to land, going through these (time, width scale, height scale) keyframes with cosine easing between them: (0, 0.3, 2.2) tall and thin, (0.35, 1.4, 0.55) squashed flat, (0.6, 0.9, 1.2), (0.8, 1.05, 0.95), (1, 1, 1); it fades in over the first 15% of that. At 3.2 seconds the letters leave one by one in reading order, 0.05 seconds apart, each over 0.4 seconds: squash to (1.35, 0.6) at 30% of the way, then stretch to (0.3, 2.8) at the end while rising 12% of the frame height (speeding up) and fading out over the last 70%. Nothing shows before 0.4 seconds, and the frame is untouched once every letter has left. Draw the text with Python and Pillow (don't rely on ffmpeg's drawtext filter), keep the size and audio, and save it as output.mp4. ``` ## Run it without Claude This is the exact script we tested. Save it as `stretchy-text.py` and run: ``` python3 stretchy-text.py input.mp4 output.mp4 ``` ``` #!/usr/bin/env python3 """Stretchy text: each letter shoots up tall and thin, squashes flat, springs back to shape, then stretches up and away. Usage: python3 stretchy-text.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 LINES = [("SKIN", 0.4, 0.17), # (word, second its first letter lands, where its baseline sits: 0 = top, 1 = bottom) ("BOUNCE", 0.8, 0.275)] STAGGER = 0.05 # seconds between one letter and the next IN = 0.5 # seconds a letter takes to land and settle OUT_START = 3.2 # second the letters start to leave OUT = 0.4 # seconds a letter takes to leave WIDTH = 0.8 # the longest word's width as a share of the frame width COLOR = (255, 255, 255) # letter color OUTLINE = 0.015 # dark outline thickness as a share of the frame width OUTLINE_COLOR = (40, 12, 60) # (time 0-1, width scale, height scale): tall and thin, squashed flat, a smaller stretch, then settled LAND = [(0, 0.3, 2.2), (0.35, 1.4, 0.55), (0.6, 0.9, 1.2), (0.8, 1.05, 0.95), (1, 1, 1)] # a quick squash, then a tall stretch that rises off the top as it fades LEAVE = [(0, 1, 1), (0.3, 1.35, 0.6), (1, 0.3, 2.8)] FONTS = ["/System/Library/Fonts/Supplemental/Arial Black.ttf", # macOS "/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf", # Linux "C:/Windows/Fonts/ariblk.ttf"] # Windows FONT_FILE = next((f for f in FONTS if Path(f).exists()), None) or sys.exit("No bold font found: add one to FONTS") def letters(): """Every letter as its own image, with its settled center x, baseline y and start time.""" stroke = round(w * OUTLINE) longest = max((word for word, _, _ in LINES), key=len) probe_font = ImageFont.truetype(FONT_FILE, 100) font = ImageFont.truetype(FONT_FILE, round(100 * w * WIDTH / probe_font.getlength(longest))) out = [] for word, start, y in LINES: x = (w - font.getlength(word)) / 2 for i, ch in enumerate(word): x0, y0, x1, y1 = font.getbbox(ch, stroke_width=stroke) img = Image.new("RGBA", (x1 - x0, y1 - y0)) ImageDraw.Draw(img).text((-x0, -y0), ch, font=font, fill=COLOR, stroke_width=stroke, stroke_fill=OUTLINE_COLOR) advance = font.getlength(ch) out.append((img, x + advance / 2, h * y, start + i * STAGGER, OUT_START + len(out) * STAGGER)) x += advance return out def shape(keys, p): """Width and height scale at time p (0-1) along keyframes, eased between each pair.""" for (t0, sx0, sy0), (t1, sx1, sy1) in zip(keys, keys[1:]): if p <= t1: k = (1 - math.cos(math.pi * (p - t0) / (t1 - t0))) / 2 return sx0 + (sx1 - sx0) * k, sy0 + (sy1 - sy0) * k return keys[-1][1:] def overlay(t): img = Image.new("RGBA", (w, h)) for pic, cx, base, start, leave in pictures: if t < start or t >= leave + OUT: continue if t < leave: p = min((t - start) / IN, 1) sx, sy = shape(LAND, p) fade, rise = min(p / 0.15, 1), 0 else: p = (t - leave) / OUT sx, sy = shape(LEAVE, p) fade, rise = 1 - max(p - 0.3, 0) / 0.7, h * 0.12 * p * p letter = pic.resize((max(1, round(pic.width * sx)), max(1, round(pic.height * sy))), Image.LANCZOS) if fade < 1: letter.putalpha(letter.getchannel("A").point(lambda a: a * fade)) img.alpha_composite(letter, (round(cx - letter.width / 2), round(base - rise - letter.height))) 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) pictures = letters() render(src, out) ``` ## More captions and text - [AI chat reply animation **AI chat reply animation**](https://www.recharm.com/effects/ai-chat-typing) - [Animated bar chart **Animated bar chart**](https://www.recharm.com/effects/animated-bar-chart) - [Animated checklist **Animated checklist**](https://www.recharm.com/effects/animated-checklist) - [Animated line graph **Animated line graph**](https://www.recharm.com/effects/animated-line-graph) - [Animated pie chart **Animated pie chart**](https://www.recharm.com/effects/animated-pie-chart) ## Find 3x _winning ads_ Recharm cuts your ad footage into tagged, searchable clips: hooks, testimonials, product shots. 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