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Static Ghost

Remove static watermarks from videos using LaMa inpainting.

Takes a video with a fixed-position watermark (TV logo, site branding, corner text), detects or lets you specify the watermark location, and removes it frame-by-frame using the LaMa inpainting model via IOPaint.

How it works

Input video → Extract frames → Crop watermark region → LaMa inpaint → Paste back → Reassemble video
              (FFmpeg)         (multiprocess)          (IOPaint)       (multiprocess)  (FFmpeg)

The crop-and-paste optimization only processes the small watermark region instead of the full frame — typically 10-15x fewer pixels, making a 10-minute 1080p video processable in ~2 hours on CPU instead of 20+.

Install

Prerequisites:

brew install ffmpeg        # or your package manager
pip install iopaint        # LaMa inpainting engine

Install static-ghost:

git clone https://github.com/redredchen01/static-ghost.git
cd static-ghost
pip install -e ".[dev]"

macOS note: If iopaint is not in PATH after install:

export PATH="$HOME/Library/Python/3.9/bin:$PATH"

Usage

Quick start — draw the watermark region

static-ghost pick video.mp4 --dilation 15 --device mps -o video_clean.mp4

Opens your browser with a frame from the video. Draw a rectangle around the watermark, click confirm, and it runs the full removal pipeline.

Specify coordinates directly

static-ghost remove video.mp4 --region 1400,920,520,160 --dilation 15 --device mps

Coordinates are x,y,width,height from the top-left corner. Multiple watermarks:

static-ghost remove video.mp4 \
  --region 1400,920,520,160 \
  --region 20,15,200,60 \
  --dilation 15

Auto-detect watermark

static-ghost detect video.mp4

Uses multi-frame differencing to find regions that stay static across the video. Works best on opaque, high-contrast watermarks. For semi-transparent watermarks, raise the threshold:

static-ghost detect video.mp4 --threshold 35

Full auto pipeline

static-ghost remove video.mp4 --device mps

Auto-detects → shows preview → asks for confirmation → removes.

Options

Flag Default Description
--region x,y,w,h Watermark bounding box (repeatable)
--pick Open browser to draw region
--dilation N 5 Expand mask by N pixels (use 10-15 for logos)
--device cpu|mps cpu mps = Apple Metal GPU, ~2x faster
--threshold N 15 Detection sensitivity (higher = more permissive)
--keep-temp Keep extracted frames for debugging
-o PATH {name}_clean.mp4 Output path

Performance

Crop-and-paste mode (default). Times for 1080p 30fps video:

Video length Frames CPU MPS (Apple Metal)
30 sec 900 ~8 min ~4 min
10 min 18,000 ~2.5 hr ~1.5 hr
30 min 54,000 ~7.5 hr ~4 hr

Actual times depend on watermark size and system load. Use --device mps on macOS for best performance.

Tips

  • Always test on 30 seconds first. Extract a clip with ffmpeg -i input.mp4 -t 30 -c copy test.mp4 and verify the result before committing to a full video.
  • Be generous with region size. It's better to over-cover the watermark area than to leave edges visible. Add 50-100px padding beyond the visible watermark.
  • Dilation matters. Default is 5px. For large logos with solid color blocks, use 15-20.
  • Semi-transparent watermarks are harder. Auto-detect may fail — use --pick or --region to specify manually.

Project structure

static_ghost/
├── cli.py              # CLI entry point and flow orchestration
├── video_engine.py     # FFmpeg: probe, extract frames, merge
├── detector.py         # Multi-frame differencing watermark detection
├── mask_generator.py   # Coordinates → binary mask PNG
├── fast_inpaint.py     # Crop-inpaint-paste with multiprocessing
├── inpainter.py        # IOPaint CLI wrapper
└── picker.py           # Browser-based interactive region selector

Tests

pip install -e ".[dev]"
pytest tests/ -v

20 tests covering all modules. Tests mock IOPaint so they run without it installed.


Agent Integration Guide

This section is for AI coding agents (Claude Code, Cursor, Copilot, etc.) that need to use static-ghost programmatically.

When to use this tool

  • User wants to remove a watermark/logo from a video (not an image)
  • The watermark is static — fixed position across all frames
  • Examples: TV station logos, website branding, "SAMPLE" overlays

Do NOT use for: single images, moving/animated watermarks, subtitles (use subtitle extraction instead).

Python API

from static_ghost.video_engine import probe, extract_sample_frames, extract_all_frames, merge
from static_ghost.detector import Region, detect_static_regions, save_preview
from static_ghost.mask_generator import create_mask
from static_ghost.fast_inpaint import fast_remove
from static_ghost.inpainter import check_iopaint

Step 1: Probe

meta = probe(video_path)
# Returns: {"width": 1920, "height": 1080, "fps": 30.0, "duration": 637.1, "codec": "h264", "audio_codec": "aac"}
total_frames = int(meta["fps"] * meta["duration"])

Step 2: Get watermark coordinates

Option A — User provides coordinates:

regions = [Region(x=1400, y=920, w=520, h=160, confidence=1.0)]

Option B — Auto-detect:

import tempfile
tmp = tempfile.mkdtemp()
sample_paths = extract_sample_frames(video_path, n=30, output_dir=tmp)
regions = detect_static_regions(sample_paths, threshold=15)
# If empty, try threshold=25, 35, 50
# If still empty, fall back to visual inspection or ask user

Option C — Visual inspection (when agent can see images):

# Extract sample frames
paths = extract_sample_frames(video_path, n=5, output_dir=tmp)
# Read frames with vision tool, inspect corners for watermarks
# Crop suspected area to verify:
import cv2
img = cv2.imread(paths[0])
crop = img[h-150:h, w-500:w]  # bottom-right corner
cv2.imwrite("/tmp/corner.png", crop)
# Estimate coordinates from visual inspection

Step 3: Test on 30-second clip

import subprocess
subprocess.run(["ffmpeg", "-y", "-i", video_path, "-t", "30", "-c", "copy", "/tmp/test_30s.mp4"], capture_output=True, check=True)

Run removal on clip, verify output visually, then proceed to full video.

Step 4: Run removal

from static_ghost.cli import parse_args, cmd_remove

args = parse_args([
    "remove", video_path,
    "--region", "1400,920,520,160",
    "--dilation", "15",
    "--device", "mps",          # "cpu" if no Metal GPU
    "-o", output_path,
])
cmd_remove(args)

For long videos, run in background (if your environment supports it) and check progress:

import os
# Count output frames in temp dir
tmp_dirs = [d for d in os.listdir("/var/folders/...") if d.startswith("static_ghost_")]
# Compare against total_frames for progress

Step 5: Verify

orig_meta = probe(video_path)
clean_meta = probe(output_path)
assert orig_meta["width"] == clean_meta["width"]
assert orig_meta["height"] == clean_meta["height"]
assert abs(orig_meta["duration"] - clean_meta["duration"]) < 1.0
assert clean_meta["audio_codec"] is not None
# Visually verify sample frames from output

Decision tree for agents

User wants watermark removed from video
│
├─ User provided coordinates? → Use them directly
├─ Auto-detect finds regions? → Show to user for confirmation
├─ Auto-detect fails?
│   ├─ Agent has vision? → Extract frames, inspect corners, estimate coords
│   └─ Agent has no vision? → Ask user for coordinates or use --pick
│
├─ Test on 30s clip
│   ├─ Watermark gone? → Run full video
│   ├─ Partially visible? → Increase region size / dilation, re-test
│   └─ Artifacts? → Reduce dilation, re-test
│
└─ Run full video (background for >5 min videos)

Time estimation

Before running the full video, benchmark 5 frames to estimate total time:

import time
test_paths = extract_sample_frames(video_path, n=5, output_dir="/tmp/bench_in")
os.makedirs("/tmp/bench_out", exist_ok=True)
start = time.time()
fast_remove("/tmp/bench_in", "/tmp/bench_out", regions, dilation=15, device="mps")
per_frame = (time.time() - start) / 5
est_minutes = per_frame * total_frames / 60
print(f"Estimated: {est_minutes:.0f} minutes")

Common pitfalls

Mistake Fix
Region too small Add 50-100px padding beyond visible watermark edges
Dilation too low for large logos Use --dilation 15 for logos with solid color blocks
Running full video without testing Always test on 30s clip first
Forgetting --device mps on macOS 2x speed improvement for free
Auto-detect on semi-transparent watermarks Will likely fail — use manual coordinates
Not checking disk space 1080p 10min ≈ 40-80GB temp space

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