claude-code-minoan

Photo to Slack Emoji Converter & Image Editor

Transform any photo into a classic Slack-optimized emoji using Google's Nano Banana Pro (Gemini 3 Pro Image) model with automatic subject identification and style transformation. NEW: Edit existing images with natural language prompts!

When to Use This Skill

Use this skill when:

• Converting photos into Slack custom emojis
• Editing existing images/emojis (add hats, change colors, add accessories, etc.)
• Creating icon-style representations of people, pets, objects, or concepts
• Need automatic subject identification and isolation
• Transforming photos to match classic emoji aesthetics (flat, simple, expressive)
• Ensuring Slack's strict 64KB file size and dimension requirements are met

Overview

This skill combines:

1. Google Nano Banana Pro (Gemini 3 Pro Image) - AI-powered subject identification, style transformation, and image editing with superior quality
2. Slack Emoji Validators - Ensures compliance with Slack's 64KB limit and optimal dimensions
3. Automatic Optimization - Color quantization, compression, and size validation

Two Main Workflows

1. Photo-to-Emoji Conversion (Original)

Photo Input → Gemini Identifies Subject → Transform to Emoji Style → Optimize for Slack → Validate

2. Image Editing (NEW!)

Existing Image → Natural Language Edit Prompt → Gemini Edits Image → Optimize (optional) → Save

How It Works

Photo Input → Gemini Identifies Subject → Transform to Emoji Style → Optimize for Slack → Validate

Workflow Steps:

1. Upload photo - Provide path to source image
2. AI identifies subject - Gemini's visual reasoning determines the main subject
3. Style transformation - Converts to emoji/icon/sticker style with descriptive prompt
4. Optimization - Reduces to 128x128, limits colors to 32-48, compresses to <64KB
5. Validation - Confirms Slack requirements are met

Quick Start

Basic Photo-to-Emoji Usage

from core.photo_to_emoji import convert_photo_to_emoji

# Convert a photo to a Slack emoji
convert_photo_to_emoji(
    input_path="~/Downloads/my_cat.jpg",
    output_path="~/Desktop/cat_emoji.png",
    style="classic_emoji",
    description="happy cat face"  # Optional: helps guide transformation
)

NEW: Image Editing Usage

IMPORTANT: Never override existing generated images. Always use a different output filename to preserve the original. Iterative editing works best when you can compare versions.

# Command line (easiest way)
python edit_image.py input.jpg output.png "add a party hat"
python edit_image.py cat_emoji.png cat_with_sunglasses.png "add cool sunglasses" --optimize

# WRONG: Don't overwrite the original
# python edit_image.py cat_emoji.png cat_emoji.png "edit" ❌

# CORRECT: Use a new filename
# python edit_image.py cat_emoji.png cat_emoji_edited.png "edit" ✅

# Python API
from core.gemini_client import GeminiImageClient

client = GeminiImageClient()

# Edit an existing image
with open("cat_emoji.png", "rb") as f:
    image_data = f.read()

edited_data = client.edit_image(
    image_data=image_data,
    mime_type="image/png",
    edit_prompt="add a party hat to the cat"
)

# Always save to a NEW filename
with open("cat_with_hat.png", "wb") as f:
    f.write(edited_data)

Advanced Usage with Custom Styles

convert_photo_to_emoji(
    input_path="~/Downloads/portrait.jpg",
    output_path="~/Desktop/person_emoji.png",
    style="flat_icon",
    description="friendly person waving",
    custom_prompt="Transform this photo into a simple, flat design icon with bold outlines, minimal details, solid colors, and a white background. Focus on the subject's key features and expression."
)

Available Styles

1. classic_emoji (Recommended for most use cases)

• Round, expressive, classic emoji aesthetic
• Simplified features with bold outlines
• High contrast, vibrant colors
• Perfect for faces, animals, and expressive subjects

Example prompt template:

Transform this photo into a classic emoji style: round shape, simplified features,
bold outlines, expressive and friendly, vibrant yellow/warm tones, minimal shading,
white or transparent background. Focus on the subject's main expression.

2. flat_icon

• Minimalist, flat design
• Simple geometric shapes
• Solid colors without gradients
• Best for objects, logos, symbols

Example prompt template:

Transform this photo into a flat, minimalist icon: simple geometric shapes,
solid colors, no gradients, bold clean outlines, modern flat design aesthetic,
white background. Capture the essence of the subject with minimal detail.

3. kawaii_sticker

• Cute, playful, Japanese kawaii aesthetic
• Rounded features, large eyes
• Pastel or vibrant colors
• Best for animals, characters, food

Example prompt template:

Transform this photo into a kawaii-style sticker: cute and playful, rounded features,
large expressive eyes, simple cel-shading, vibrant color palette, bold clean outlines,
white background. Make it adorable and friendly.

4. pixel_art

• Retro 8-bit/16-bit pixel art style
• Chunky pixels, limited color palette
• Nostalgic gaming aesthetic
• Best for characters, objects, icons

Example prompt template:

Transform this photo into pixel art: 16x16 or 32x32 pixel style, retro 8-bit aesthetic,
limited color palette (8-16 colors), chunky pixels, clear subject outline,
simple shading, transparent or solid background.

5. custom

• Provide your own transformation prompt
• Full control over style description
• Use for unique or specific aesthetic needs

API Configuration

Setting up Google Gemini API Key

You'll need a Google Gemini API key to use this skill.

1. Get API Key: Visit Google AI Studio
2. Set Environment Variable:

``bash export GEMINI_API_KEY="your-api-key-here" ``

1. Or provide directly in code:

``python convert_photo_to_emoji( input_path="photo.jpg", output_path="emoji.png", api_key="your-api-key-here" ) ``

API Costs

Google Gemini 2.5 Flash Image pricing:

• $30 per 1 million output tokens
• Each image = 1290 tokens (flat rate up to 1024x1024px)
• ~$0.039 per image generated

Very cost-effective for emoji creation!

Slack Requirements

Emoji Specifications (Strict)

• Max file size: 64KB (strict enforcement)
• Optimal dimensions: 128x128 pixels
• Recommended colors: 32-48 colors maximum
• Format: PNG with transparency support

Validation

The skill automatically validates and optimizes for these requirements:

from core.validators import validate_slack_emoji

# After conversion, validate
is_valid, report = validate_slack_emoji("emoji.png")

if is_valid:
    print("✅ Ready to upload to Slack!")
else:
    print(f"❌ Issues: {report}")

Examples

Example 1: Pet Photo to Emoji

# Convert a dog photo to a happy emoji
convert_photo_to_emoji(
    input_path="~/Photos/my_dog.jpg",
    output_path="~/Desktop/happy_dog_emoji.png",
    style="classic_emoji",
    description="happy golden retriever smiling"
)

Result: A round, simplified emoji-style dog face with expressive eyes and a big smile.

Example 2: Person Portrait to Icon

# Convert a headshot to a professional icon
convert_photo_to_emoji(
    input_path="~/Photos/headshot.jpg",
    output_path="~/Desktop/person_icon.png",
    style="flat_icon",
    description="professional person with glasses"
)

Result: A minimalist, flat design icon representation of the person.

Example 3: Food Photo to Kawaii Sticker

# Convert a pizza photo to cute sticker
convert_photo_to_emoji(
    input_path="~/Photos/pizza.jpg",
    output_path="~/Desktop/kawaii_pizza.png",
    style="kawaii_sticker",
    description="cute pizza slice with happy face"