slack-gif-creator
Knowledge and utilities for creating animated GIFs optimized for Slack. Provides constraints, validation tools, and animation concepts. Use when users request animated GIFs for Slack like "make me a GIF of X doing Y for Slack."
Documentation
Slack GIF Creator
A toolkit providing utilities and knowledge for creating animated GIFs optimized for Slack.
Slack Requirements
Dimensions:
- Emoji GIFs: 128x128 (recommended)
- Message GIFs: 480x480
Parameters:
- FPS: 10-30 (lower is smaller file size)
- Colors: 48-128 (fewer = smaller file size)
- Duration: Keep under 3 seconds for emoji GIFs
Core Workflow
from core.gif_builder import GIFBuilder
from PIL import Image, ImageDraw
# 1. Create builder
builder = GIFBuilder(width=128, height=128, fps=10)
# 2. Generate frames
for i in range(12):
frame = Image.new('RGB', (128, 128), (240, 248, 255))
draw = ImageDraw.Draw(frame)
# Draw your animation using PIL primitives
# (circles, polygons, lines, etc.)
builder.add_frame(frame)
# 3. Save with optimization
builder.save('output.gif', num_colors=48, optimize_for_emoji=True)
Drawing Graphics
Working with User-Uploaded Images
If a user uploads an image, consider whether they want to:
- Use it directly (e.g., "animate this", "split this into frames")
- Use it as inspiration (e.g., "make something like this")
Load and work with images using PIL:
from PIL import Image
uploaded = Image.open('file.png')
# Use directly, or just as reference for colors/style
Drawing from Scratch
When drawing graphics from scratch, use PIL ImageDraw primitives:
from PIL import ImageDraw
draw = ImageDraw.Draw(frame)
# Circles/ovals
draw.ellipse([x1, y1, x2, y2], fill=(r, g, b), outline=(r, g, b), width=3)
# Stars, triangles, any polygon
points = [(x1, y1), (x2, y2), (x3, y3), ...]
draw.polygon(points, fill=(r, g, b), outline=(r, g, b), width=3)
# Lines
draw.line([(x1, y1), (x2, y2)], fill=(r, g, b), width=5)
# Rectangles
draw.rectangle([x1, y1, x2, y2], fill=(r, g, b), outline=(r, g, b), width=3)
Don't use: Emoji fonts (unreliable across platforms) or assume pre-packaged graphics exist in this skill.
Making Graphics Look Good
Graphics should look polished and creative, not basic. Here's how:
Use thicker lines - Always set width=2 or higher for outlines and lines. Thin lines (width=1) look choppy and amateurish.
Add visual depth:
- Use gradients for backgrounds (
create_gradient_background) - Layer multiple shapes for complexity (e.g., a star with a smaller star inside)
Make shapes more interesting:
- Don't just draw a plain circle - add highlights, rings, or patterns
- Stars can have glows (draw larger, semi-transparent versions behind)
- Combine multiple shapes (stars + sparkles, circles + rings)
Pay attention to colors:
- Use vibrant, complementary colors
- Add contrast (dark outlines on light shapes, light outlines on dark shapes)
- Consider the overall composition
For complex shapes (hearts, snowflakes, etc.):
- Use combinations of polygons and ellipses
- Calculate points carefully for symmetry
- Add details (a heart can have a highlight curve, snowflakes have intricate branches)
Be creative and detailed! A good Slack GIF should look polished, not like placeholder graphics.
Available Utilities
GIFBuilder (core.gif_builder)
Assembles frames and optimizes for Slack:
builder = GIFBuilder(width=128, height=128, fps=10)
builder.add_frame(frame) # Add PIL Image
builder.add_frames(frames) # Add list of frames
builder.save('out.gif', num_colors=48, optimize_for_emoji=True, remove_duplicates=True)
Validators (core.validators)
Check if GIF meets Slack requirements:
from core.validators import validate_gif, is_slack_ready
# Detailed validation
passes, info = validate_gif('my.gif', is_emoji=True, verbose=True)
# Quick check
if is_slack_ready('my.gif'):
print("Ready!")
Easing Functions (core.easing)
Smooth motion instead of linear:
from core.easing import interpolate
# Progress from 0.0 to 1.0
t = i / (num_frames - 1)
# Apply easing
y = interpolate(start=0, end=400, t=t, easing='ease_out')
# Available: linear, ease_in, ease_out, ease_in_out,
# bounce_out, elastic_out, back_out
Frame Helpers (core.frame_composer)
Convenience functions for common needs:
from core.frame_composer import (
create_blank_frame, # Solid color background
create_gradient_background, # Vertical gradient
draw_circle, # Helper for circles
draw_text, # Simple text rendering
draw_star # 5-pointed star
)
Animation Concepts
Shake/Vibrate
Offset object position with oscillation:
- Use
math.sin()ormath.cos()with frame index - Add small random variations for natural feel
- Apply to x and/or y position
Pulse/Heartbeat
Scale object size rhythmically:
- Use
math.sin(t * frequency * 2 * math.pi)for smooth pulse - For heartbeat: two quick pulses then pause (adjust sine wave)
- Scale between 0.8 and 1.2 of base size
Bounce
Object falls and bounces:
- Use
interpolate()wi
Quick Info
- Source
- Anthropic
- Category
- Creative & Media
- Repository
- View Repo
- Scraped At
- Jan 26, 2026
Tags
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