Nm Scry Gif Generation

Post-process video files and generate optimized GIFs. Converts webm/mp4

Security Scan

The skill's instructions match its stated purpose (video → GIF via ffmpeg) but there are small inconsistencies (undeclared environment variables and metadata mismatches) that should be clarified before use.

Purpose & Capability

The skill's name/description and runtime instructions are coherent: it documents using ffmpeg/ffprobe to convert webm/mp4 to GIFs, provide presets, and verify output. However, the registry metadata lists no required binaries while the SKILL.md repeatedly depends on ffmpeg/ffprobe; that omission is an inconsistency in declared requirements.

Instruction Scope

SKILL.md contains concrete shell snippets that check local files, run file/ffprobe/ffmpeg, and read environment variables ($INPUT_FILE, $OUTPUT_FILE). This is in-scope for a conversion tool, but the SKILL.md expects those env vars to exist while the skill metadata declares none — the agent would need explicit input paths. The instructions also use exit codes and suggest installing ffmpeg; there is no directive to transmit data externally.

Install Mechanism

This is an instruction-only skill with no install spec and no code files. That minimizes install-time risk (nothing downloaded or written by the skill itself).

Credentials

The skill requests no credentials and does not require network auth. However the runtime examples rely on environment variables (INPUT_FILE, OUTPUT_FILE) that are not declared in requires.env in the registry metadata — a mismatch that should be fixed so callers know what inputs are required. No sensitive secrets are requested.

Persistence & Privilege

always:false and no persistent installs or modifications are requested. The skill does run local shell commands (expected), but it does not request elevated platform privileges or modify other skills/configs.

What to consider before installing

This skill appears to do what it claims (convert video files to GIFs using ffmpeg), but before installing: 1) Confirm ffmpeg and ffprobe are available on the host (the SKILL.md assumes them). 2) Provide explicit input/output paths — the skill's examples use $INPUT_FILE and $OUTPUT_FILE but the registry doesn't declare them. 3) Test the skill on non-sensitive/sample files first because it runs shell commands and accesses local files. 4) Ask the publisher to fix metadata inconsistencies (declare required binaries/env) and confirm the version in SKILL.md vs registry. If you don't want the agent to run arbitrary shell commands, don't enable autonomous invocation for this skill or restrict it to manual invocation only.

Night Market Skill — ported from claude-night-market/scry. For the full experience with agents, hooks, and commands, install the Claude Code plugin.

Table of Contents

• Overview
• Required TodoWrite Items
• Process
• Step 1: Validate Input File
• Step 2: Check ffmpeg Installation
• Step 3: Execute Conversion
• Basic Conversion (Fast, Larger File)
• High Quality with Palette Generation (Recommended)
• Maximum Quality with Dithering
• Optimization Options
• Common Presets
• Step 4: Verify Output
• Exit Criteria
• Troubleshooting
• Large Output File
• Color Banding
• Slow Conversion

GIF Generation Skill

Post-process video files (webm/mp4) and generate optimized GIF output with configurable quality settings.

When To Use

• Converting recordings to animated GIF format
• Creating lightweight demo animations

When NOT To Use

• High-quality video output - use full recording tools
• Static image generation without animation needs

Overview

This skill handles the conversion of video recordings (typically from browser automation) to GIF format. It provides multiple quality presets and optimization options to balance file size with visual quality.

Required TodoWrite Items

- Validate input video file exists
- Check ffmpeg installation
- Execute GIF conversion
- Verify output and report results

Verification: Run the command with --help flag to verify availability.

Process

Step 1: Validate Input File

Confirm the source video file exists and is a supported format:

# Check file exists and get info
if [[ -f "$INPUT_FILE" ]]; then
    file "$INPUT_FILE"
    ffprobe -v quiet -show_format -show_streams "$INPUT_FILE" 2>/dev/null | head -20
else
    echo "Error: Input file not found: $INPUT_FILE"
    exit 1
fi

Verification: Run the command with --help flag to verify availability.

Supported input formats: .webm, .mp4, .mov, .avi

Step 2: Check ffmpeg Installation

Verify ffmpeg is available:

if ! command -v ffmpeg &> /dev/null; then
    echo "Error: ffmpeg is not installed"
    echo "Install with: sudo apt install ffmpeg (Linux) or brew install ffmpeg (macOS)"
    exit 1
fi
ffmpeg -version | head -1

Verification: Run the command with --help flag to verify availability.

Step 3: Execute Conversion

Choose the appropriate conversion command based on quality requirements:

Basic Conversion (Fast, Larger File)

ffmpeg -i input.webm -vf "fps=10,scale=800:-1" output.gif

Verification: Run the command with --help flag to verify availability.

High Quality with Palette Generation (Recommended)

ffmpeg -i input.webm -vf "fps=10,scale=800:-1:flags=lanczos,split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse" output.gif

Verification: Run the command with --help flag to verify availability.

Maximum Quality with Dithering

ffmpeg -i input.webm -vf "fps=15,scale=1024:-1:flags=lanczos,split[s0][s1];[s0]palettegen=max_colors=256:stats_mode=single[p];[s1][p]paletteuse=dither=bayer:bayer_scale=5" output.gif

Verification: Run the command with --help flag to verify availability.

Optimization Options

Option	Description	Recommended Value
fps	Frames per second	10-15 for smooth, 5-8 for smaller files
scale	Width in pixels (-1 maintains aspect ratio)	800 for web, 480 for thumbnails
flags=lanczos	High-quality scaling algorithm	Always use for best quality
palettegen	Generate optimized color palette	Use for quality-critical output
dither	Dithering algorithm	bayer for patterns, floyd_steinberg for smooth

Common Presets

# Thumbnail (small, fast loading)
ffmpeg -i input.webm -vf "fps=8,scale=480:-1:flags=lanczos,split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse" thumbnail.gif

# Documentation (balanced)
ffmpeg -i input.webm -vf "fps=10,scale=800:-1:flags=lanczos,split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse" docs.gif

# High-fidelity demo
ffmpeg -i input.webm -vf "fps=15,scale=1024:-1:flags=lanczos,split[s0][s1];[s0]palettegen=max_colors=256[p];[s1][p]paletteuse" demo.gif

Verification: Run the command with --help flag to verify availability.

Step 4: Verify Output

Confirm successful conversion and report metrics:

if [[ -f "$OUTPUT_FILE" ]]; then
    echo "GIF generated successfully: $OUTPUT_FILE"

    # Report file size
    SIZE=$(du -h "$OUTPUT_FILE" | cut -f1)
    echo "File size: $SIZE"

    # Get dimensions and frame count
    ffprobe -v quiet -select_streams v:0 -show_entries stream=width,height,nb_frames -of csv=p=0 "$OUTPUT_FILE"
else
    echo "Error: GIF generation failed"
    exit 1
fi

Verification: Run the command with --help flag to verify availability.

Exit Criteria

• Input file validated as existing video format
• ffmpeg confirmed available
• GIF file created at specified output path
• Output file size reported to user
• No ffmpeg errors during conversion

Troubleshooting

Large Output File

Reduce quality settings:

# Lower fps and resolution
ffmpeg -i input.webm -vf "fps=8,scale=640:-1:flags=lanczos,split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse" smaller.gif

Verification: Run the command with --help flag to verify availability.

Color Banding

Use dithering:

ffmpeg -i input.webm -vf "fps=10,scale=800:-1:flags=lanczos,split[s0][s1];[s0]palettegen[p];[s1][p]paletteuse=dither=floyd_steinberg" smooth.gif

Verification: Run the command with --help flag to verify availability.

Slow Conversion

Use basic conversion without palette generation for speed:

ffmpeg -i input.webm -vf "fps=10,scale=800:-1" quick.gif

Verification: Run the command with --help flag to verify availability.