---
name: slack-gif-creator
description: Create animated GIFs optimized for Slack with validators for size constraints and composable animation primitives.
license: Complete terms in LICENSE.txt
---

# Slack GIF Creator - Flexible Toolkit

A toolkit for creating animated GIFs optimized for Slack. Provides validators for Slack's constraints, composable animation primitives, and optional helper utilities. **Apply these tools however needed to achieve the creative vision.**

## Slack's Requirements

Slack has specific requirements for GIFs based on their use:

**Message GIFs:**
- Max size: ~2MB
- Optimal dimensions: 480x480
- Typical FPS: 15-20
- Color limit: 128-256
- Duration: 2-5s

**Emoji GIFs:**
- Max size: 64KB (strict limit)
- Optimal dimensions: 128x128
- Typical FPS: 10-12
- Color limit: 32-48
- Duration: 1-2s

**Emoji GIFs are challenging** - the 64KB limit is strict. Strategies that help:
- Limit to 10-15 frames total
- Use 32-48 colors maximum
- Keep designs simple
- Avoid gradients
- Validate file size frequently

## Toolkit Structure

This skill provides three types of tools:

1. **Validators** - Check if a GIF meets Slack's requirements
2. **Animation Primitives** - Composable building blocks for motion (shake, bounce, move, kaleidoscope)
3. **Helper Utilities** - Optional functions for common needs (text, colors, effects)

**Complete creative freedom is available in how these tools are applied.**

## Core Validators

To ensure a GIF meets Slack's constraints, use these validators:

```python
from core.gif_builder import GIFBuilder

# After creating your GIF, check if it meets requirements
builder = GIFBuilder(width=128, height=128, fps=10)
# ... add your frames however you want ...

# Save and check size
info = builder.save('emoji.gif', num_colors=48, optimize_for_emoji=True)

# The save method automatically warns if file exceeds limits
# info dict contains: size_kb, size_mb, frame_count, duration_seconds
```

**File size validator**:
```python
from core.validators import check_slack_size

# Check if GIF meets size limits
passes, info = check_slack_size('emoji.gif', is_emoji=True)
# Returns: (True/False, dict with size details)
```

**Dimension validator**:
```python
from core.validators import validate_dimensions

# Check dimensions
passes, info = validate_dimensions(128, 128, is_emoji=True)
# Returns: (True/False, dict with dimension details)
```

**Complete validation**:
```python
from core.validators import validate_gif, is_slack_ready

# Run all validations
all_pass, results = validate_gif('emoji.gif', is_emoji=True)

# Or quick check
if is_slack_ready('emoji.gif', is_emoji=True):
    print("Ready to upload!")
```

## Animation Primitives

These are composable building blocks for motion. Apply these to any object in any combination:

### Shake
```python
from templates.shake import create_shake_animation

# Shake an emoji
frames = create_shake_animation(
    object_type='emoji',
    object_data={'emoji': '😱', 'size': 80},
    num_frames=20,
    shake_intensity=15,
    direction='both'  # or 'horizontal', 'vertical'
)
```

### Bounce
```python
from templates.bounce import create_bounce_animation

# Bounce a circle
frames = create_bounce_animation(
    object_type='circle',
    object_data={'radius': 40, 'color': (255, 100, 100)},
    num_frames=30,
    bounce_height=150
)
```

### Spin / Rotate
```python
from templates.spin import create_spin_animation, create_loading_spinner

# Clockwise spin
frames = create_spin_animation(
    object_type='emoji',
    object_data={'emoji': '🔄', 'size': 100},
    rotation_type='clockwise',
    full_rotations=2
)

# Wobble rotation
frames = create_spin_animation(rotation_type='wobble', full_rotations=3)

# Loading spinner
frames = create_loading_spinner(spinner_type='dots')
```

### Pulse / Heartbeat
```python
from templates.pulse import create_pulse_animation, create_attention_pulse

# Smooth pulse
frames = create_pulse_animation(
    object_data={'emoji': '❤️', 'size': 100},
    pulse_type='smooth',
    scale_range=(0.8, 1.2)
)

# Heartbeat (double-pump)
frames = create_pulse_animation(pulse_type='heartbeat')

# Attention pulse for emoji GIFs
frames = create_attention_pulse(emoji='⚠️', num_frames=20)
```

### Fade
```python
from templates.fade import create_fade_animation, create_crossfade

# Fade in
frames = create_fade_animation(fade_type='in')

# Fade out
frames = create_fade_animation(fade_type='out')

# Crossfade between two emojis
frames = create_crossfade(
    object1_data={'emoji': '😊', 'size': 100},
    object2_data={'emoji': '😂', 'size': 100}
)
```

### Zoom
```python
from templates.zoom import create_zoom_animation, create_explosion_zoom

# Zoom in dramatically
frames = create_zoom_animation(
    zoom_type='in',
    scale_range=(0.1, 2.0),
    add_motion_blur=True
)

# Zoom out
frames = create_zoom_animation(zoom_type='out')

# Explosion zoom
frames = create_explosion_zoom(emoji='💥')
```

### Explode / Shatter
```python
from templates.explode import create_explode_animation, create_particle_burst

# Burst explosion
frames = create_explode_animation(
    explode_type='burst',
    num_pieces=25
)

# Shatter effect
frames = create_explode_animation(explode_type='shatter')

# Dissolve into particles
frames = create_explode_animation(explode_type='dissolve')

# Particle burst
frames = create_particle_burst(particle_count=30)
```

### Wiggle / Jiggle
```python
from templates.wiggle import create_wiggle_animation, create_excited_wiggle

# Jello wobble
frames = create_wiggle_animation(
    wiggle_type='jello',
    intensity=1.0,
    cycles=2
)

# Wave motion
frames = create_wiggle_animation(wiggle_type='wave')

# Excited wiggle for emoji GIFs
frames = create_excited_wiggle(emoji='🎉')
```

### Slide
```python
from templates.slide import create_slide_animation, create_multi_slide

# Slide in from left with overshoot
frames = create_slide_animation(
    direction='left',
    slide_type='in',
    overshoot=True
)

# Slide across
frames = create_slide_animation(direction='left', slide_type='across')

# Multiple objects sliding in sequence
objects = [
    {'data': {'emoji': '🎯', 'size': 60}, 'direction': 'left', 'final_pos': (120, 240)},
    {'data': {'emoji': '🎪', 'size': 60}, 'direction': 'right', 'final_pos': (240, 240)}
]
frames = create_multi_slide(objects, stagger_delay=5)
```

### Flip
```python
from templates.flip import create_flip_animation, create_quick_flip

# Horizontal flip between two emojis
frames = create_flip_animation(
    object1_data={'emoji': '😊', 'size': 120},
    object2_data={'emoji': '😂', 'size': 120},
    flip_axis='horizontal'
)

# Vertical flip
frames = create_flip_animation(flip_axis='vertical')

# Quick flip for emoji GIFs
frames = create_quick_flip('👍', '👎')
```

### Morph / Transform
```python
from templates.morph import create_morph_animation, create_reaction_morph

# Crossfade morph
frames = create_morph_animation(
    object1_data={'emoji': '😊', 'size': 100},
    object2_data={'emoji': '😂', 'size': 100},
    morph_type='crossfade'
)

# Scale morph (shrink while other grows)
frames = create_morph_animation(morph_type='scale')

# Spin morph (3D flip-like)
frames = create_morph_animation(morph_type='spin_morph')
```

### Move Effect
```python
from templates.move import create_move_animation

# Linear movement
frames = create_move_animation(
    object_type='emoji',
    object_data={'emoji': '🚀', 'size': 60},
    start_pos=(50, 240),
    end_pos=(430, 240),
    motion_type='linear',
    easing='ease_out'
)

# Arc movement (parabolic trajectory)
frames = create_move_animation(
    object_type='emoji',
    object_data={'emoji': '⚽', 'size': 60},
    start_pos=(50, 350),
    end_pos=(430, 350),
    motion_type='arc',
    motion_params={'arc_height': 150}
)

# Circular movement
frames = create_move_animation(
    object_type='emoji',
    object_data={'emoji': '🌍', 'size': 50},
    motion_type='circle',
    motion_params={
        'center': (240, 240),
        'radius': 120,
        'angle_range': 360  # full circle
    }
)

# Wave movement
frames = create_move_animation(
    motion_type='wave',
    motion_params={
        'wave_amplitude': 50,
        'wave_frequency': 2
    }
)

# Or use low-level easing functions
from core.easing import interpolate, calculate_arc_motion

for i in range(num_frames):
    t = i / (num_frames - 1)
    x = interpolate(start_x, end_x, t, easing='ease_out')
    # Or: x, y = calculate_arc_motion(start, end, height, t)
```

### Kaleidoscope Effect
```python
from templates.kaleidoscope import apply_kaleidoscope, create_kaleidoscope_animation

# Apply to a single frame
kaleido_frame = apply_kaleidoscope(frame, segments=8)

# Or create animated kaleidoscope
frames = create_kaleidoscope_animation(
    base_frame=my_frame,  # or None for demo pattern
    num_frames=30,
    segments=8,
    rotation_speed=1.0
)

# Simple mirror effects (faster)
from templates.kaleidoscope import apply_simple_mirror

mirrored = apply_simple_mirror(frame, mode='quad')  # 4-way mirror
# modes: 'horizontal', 'vertical', 'quad', 'radial'
```

**To compose primitives freely, follow these patterns:**
```python
# Example: Bounce + shake for impact
for i in range(num_frames):
    frame = create_blank_frame(480, 480, bg_color)

    # Bounce motion
    t_bounce = i / (num_frames - 1)
    y = interpolate(start_y, ground_y, t_bounce, 'bounce_out')

    # Add shake on impact (when y reaches ground)
    if y >= ground_y - 5:
        shake_x = math.sin(i * 2) * 10
        x = center_x + shake_x
    else:
        x = center_x

    draw_emoji(frame, '⚽', (x, y), size=60)
    builder.add_frame(frame)
```

## Helper Utilities

These are optional helpers for common needs. **Use, modify, or replace these with custom implementations as needed.**

### GIF Builder (Assembly & Optimization)

```python
from core.gif_builder import GIFBuilder

# Create builder with your chosen settings
builder = GIFBuilder(width=480, height=480, fps=20)

# Add frames (however you created them)
for frame in my_frames:
    builder.add_frame(frame)

# Save with optimization
builder.save('output.gif',
             num_colors=128,
             optimize_for_emoji=False)
```

Key features:
- Automatic color quantization
- Duplicate frame removal
- Size warnings for Slack limits
- Emoji mode (aggressive optimization)

### Text Rendering

For small GIFs like emojis, text readability is challenging. A common solution involves adding outlines:

```python
from core.typography import draw_text_with_outline, TYPOGRAPHY_SCALE

# Text with outline (helps readability)
draw_text_with_outline(
    frame, "BONK!",
    position=(240, 100),
    font_size=TYPOGRAPHY_SCALE['h1'],  # 60px
    text_color=(255, 68, 68),
    outline_color=(0, 0, 0),
    outline_width=4,
    centered=True
)
```

To implement custom text rendering, use PIL's `ImageDraw.text()` which works fine for larger GIFs.

### Color Management

Professional-looking GIFs often use cohesive color palettes:

```python
from core.color_palettes import get_palette

# Get a pre-made palette
palette = get_palette('vibrant')  # or 'pastel', 'dark', 'neon', 'professional'

bg_color = palette['background']
text_color = palette['primary']
accent_color = palette['accent']
```

To work with colors directly, use RGB tuples - whatever works for the use case.

### Visual Effects

Optional effects for impact moments:

```python
from core.visual_effects import ParticleSystem, create_impact_flash, create_shockwave_rings

# Particle system
particles = ParticleSystem()
particles.emit_sparkles(x=240, y=200, count=15)
particles.emit_confetti(x=240, y=200, count=20)

# Update and render each frame
particles.update()
particles.render(frame)

# Flash effect
frame = create_impact_flash(frame, position=(240, 200), radius=100)

# Shockwave rings
frame = create_shockwave_rings(frame, position=(240, 200), radii=[30, 60, 90])
```

### Easing Functions

Smooth motion uses easing instead of linear interpolation:

```python
from core.easing import interpolate

# Object falling (accelerates)
y = interpolate(start=0, end=400, t=progress, easing='ease_in')

# Object landing (decelerates)
y = interpolate(start=0, end=400, t=progress, easing='ease_out')

# Bouncing
y = interpolate(start=0, end=400, t=progress, easing='bounce_out')

# Overshoot (elastic)
scale = interpolate(start=0.5, end=1.0, t=progress, easing='elastic_out')
```

Available easings: `linear`, `ease_in`, `ease_out`, `ease_in_out`, `bounce_out`, `elastic_out`, `back_out` (overshoot), and more in `core/easing.py`.

### Frame Composition

Basic drawing utilities if you need them:

```python
from core.frame_composer import (
    create_gradient_background,  # Gradient backgrounds
    draw_emoji_enhanced,         # Emoji with optional shadow
    draw_circle_with_shadow,     # Shapes with depth
    draw_star                    # 5-pointed stars
)

# Gradient background
frame = create_gradient_background(480, 480, top_color, bottom_color)

# Emoji with shadow
draw_emoji_enhanced(frame, '🎉', position=(200, 200), size=80, shadow=True)
```

## Optimization Strategies

When your GIF is too large:

**For Message GIFs (>2MB):**
1. Reduce frames (lower FPS or shorter duration)
2. Reduce colors (128 → 64 colors)
3. Reduce dimensions (480x480 → 320x320)
4. Enable duplicate frame removal

**For Emoji GIFs (>64KB) - be aggressive:**
1. Limit to 10-12 frames total
2. Use 32-40 colors maximum
3. Avoid gradients (solid colors compress better)
4. Simplify design (fewer elements)
5. Use `optimize_for_emoji=True` in save method

## Example Composition Patterns

### Simple Reaction (Pulsing)
```python
builder = GIFBuilder(128, 128, 10)

for i in range(12):
    frame = Image.new('RGB', (128, 128), (240, 248, 255))

    # Pulsing scale
    scale = 1.0 + math.sin(i * 0.5) * 0.15
    size = int(60 * scale)

    draw_emoji_enhanced(frame, '😱', position=(64-size//2, 64-size//2),
                       size=size, shadow=False)
    builder.add_frame(frame)

builder.save('reaction.gif', num_colors=40, optimize_for_emoji=True)

# Validate
from core.validators import check_slack_size
check_slack_size('reaction.gif', is_emoji=True)
```

### Action with Impact (Bounce + Flash)
```python
builder = GIFBuilder(480, 480, 20)

# Phase 1: Object falls
for i in range(15):
    frame = create_gradient_background(480, 480, (240, 248, 255), (200, 230, 255))
    t = i / 14
    y = interpolate(0, 350, t, 'ease_in')
    draw_emoji_enhanced(frame, '⚽', position=(220, int(y)), size=80)
    builder.add_frame(frame)

# Phase 2: Impact + flash
for i in range(8):
    frame = create_gradient_background(480, 480, (240, 248, 255), (200, 230, 255))

    # Flash on first frames
    if i < 3:
        frame = create_impact_flash(frame, (240, 350), radius=120, intensity=0.6)

    draw_emoji_enhanced(frame, '⚽', position=(220, 350), size=80)

    # Text appears
    if i > 2:
        draw_text_with_outline(frame, "GOAL!", position=(240, 150),
                              font_size=60, text_color=(255, 68, 68),
                              outline_color=(0, 0, 0), outline_width=4, centered=True)

    builder.add_frame(frame)

builder.save('goal.gif', num_colors=128)
```

### Combining Primitives (Move + Shake)
```python
from templates.shake import create_shake_animation

# Create shake animation
shake_frames = create_shake_animation(
    object_type='emoji',
    object_data={'emoji': '😰', 'size': 70},
    num_frames=20,
    shake_intensity=12
)

# Create moving element that triggers the shake
builder = GIFBuilder(480, 480, 20)
for i in range(40):
    t = i / 39

    if i < 20:
        # Before trigger - use blank frame with moving object
        frame = create_blank_frame(480, 480, (255, 255, 255))
        x = interpolate(50, 300, t * 2, 'linear')
        draw_emoji_enhanced(frame, '🚗', position=(int(x), 300), size=60)
        draw_emoji_enhanced(frame, '😰', position=(350, 200), size=70)
    else:
        # After trigger - use shake frame
        frame = shake_frames[i - 20]
        # Add the car in final position
        draw_emoji_enhanced(frame, '🚗', position=(300, 300), size=60)

    builder.add_frame(frame)

builder.save('scare.gif')
```

## Philosophy

This toolkit provides building blocks, not rigid recipes. To work with a GIF request:

1. **Understand the creative vision** - What should happen? What's the mood?
2. **Design the animation** - Break it into phases (anticipation, action, reaction)
3. **Apply primitives as needed** - Shake, bounce, move, effects - mix freely
4. **Validate constraints** - Check file size, especially for emoji GIFs
5. **Iterate if needed** - Reduce frames/colors if over size limits

**The goal is creative freedom within Slack's technical constraints.**

## Dependencies

To use this toolkit, install these dependencies only if they aren't already present:

```bash
pip install pillow imageio numpy
```