--- title: "How to add a blur-in text with Claude (tested prompt and script)" description: "A deep plum headline above the product starts as an unreadable smudge and pulls into focus as crisp, sharp letters. Install one skill and ask Claude Code, or run the Python script we tested yourself." url: https://www.recharm.com/effects/blur-in-text --- # How to add a blur-in text with Claude A deep plum headline above the product starts as an unreadable smudge and pulls into focus as crisp, sharp letters. 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 blur-in text to input.mp4 Text: Skin, renewed ``` ## 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 blur-in 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 | | ---------- | --------------- | --------------------------------------------------- | | `TEXT` | `Skin, renewed` | The headline. | | `START` | `0.8` | Second the text starts to appear. | | `FOCUS` | `1.2` | Seconds it takes to sharpen. | | `MAX_BLUR` | `0.05` | Starting blur radius as a share of the frame width. | | `COLOR` | `(50, 20, 80)` | Text color. | ## Without the skill Don’t want to install the skill? Paste this prompt into Claude Code and Claude writes the script itself. ``` Add blur-in text to input.mp4: the words "Skin, renewed" in bold sans-serif, deep plum (50, 20, 80), text height 12% of the frame width, centered horizontally and 11% down the frame. Nothing shows before 0.8 seconds. From 0.8 seconds the text appears with a Gaussian blur of radius 5% of the frame width, fading from transparent to full opacity over the first 0.3 seconds, and the blur eases (smoothstep) down to 0 so the letters are fully sharp at 2.0 seconds; then the text stays sharp to the end. Use Python with Pillow to draw and blur the text (don't use ffmpeg's drawtext filter) and ffmpeg to put it on the video, keep the audio, and save it as output.mp4. ``` ## Run it without Claude This is the exact script we tested. Save it as `blur-in-text.py` and run: ``` python3 blur-in-text.py input.mp4 output.mp4 ``` ``` #!/usr/bin/env python3 """Blur-in text: a deep plum headline appears as a soft smudge and sharpens into crisp letters, then stays. Usage: python3 blur-in-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, ImageFilter, ImageFont TEXT = "Skin, renewed" # the headline START = 0.8 # second the text starts to appear FOCUS = 1.2 # seconds it takes to sharpen MAX_BLUR = 0.05 # starting blur radius as a share of the frame width Y = 0.11 # text center, 0-1 down the frame SIZE = 0.12 # text height as a share of the frame width COLOR = (50, 20, 80) # text color, deep plum 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 bold font found: add one to FONTS") def letters(): """The text as a white-on-black mask the size of the frame.""" mask = Image.new("L", (w, h)) font = ImageFont.truetype(FONT_FILE, round(w * SIZE)) ImageDraw.Draw(mask).text((w / 2, h * Y), TEXT, font=font, anchor="mm", fill=255) return mask def overlay(t): """The text blurred by a radius that eases from MAX_BLUR to 0, fading up over the first quarter.""" p = min(max((t - START) / FOCUS, 0), 1) if p <= 0: return blank ease = p * p * (3 - 2 * p) radius = MAX_BLUR * w * (1 - ease) alpha = mask.filter(ImageFilter.GaussianBlur(radius)) if radius > 0.3 else mask opacity = min(p / 0.25, 1) img = Image.new("RGBA", (w, h), COLOR) img.putalpha(alpha.point(lambda v: round(v * opacity))) 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) sharp = overlay(START + FOCUS) for i in range(math.ceil(duration * fps)): t = i / fps ff.stdin.write((sharp if t >= START + FOCUS else overlay(t)).tobytes()) ff.stdin.close() if ff.wait(): sys.exit("ffmpeg failed") src, out = sys.argv[1:3] w, h, rate, fps, duration = probe(src) mask = letters() blank = Image.new("RGBA", (w, h)) 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. Find the shots that win, add the effect with Claude, and ship 3x more ad edits. [Start 14-day free trial](https://www.recharm.com/get-started)