slack-gif-creator

# 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 ```python 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: ```python 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: ```python 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: ```python 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: ```python 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: ```python 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: ```python 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()` or `math.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()` with `easing='bounce_out'` for landing - Use `easing='ease_in'` for falling (accelerating) - Apply gravity by increasing y velocity each frame ### Spin/Rotate Rotate object around center: - PIL: `image.rotate(angle, resample=Image.BICUBIC)` - For wobble: use sine wave for angle instead of linear ### Fade In/Out Gradually appear or disappear: - Create RGBA image, adjust alpha channel - Or use `Image.blend(image1, image2, alpha)` - Fade in: alpha from 0 to 1 - Fade out: alpha from 1 to 0 ### Slide Move object from off-screen to position: - Start position: outside frame bounds - End position: target location - Use `interpolate()` with `easing='ease_out'` for smooth stop - For overshoot: use `easing='back_out'` ### Zoom Scale and position for zoom effect: - Zoom in: scale from 0.1 to 2.0, crop center - Zoom out: scale from 2.0 to 1.0 - Can add motion blur for drama (PIL filter) ### Explode/Particle Burst Create particles radiating outward: - Generate particles with random angles and velocities - Update each particle: `x += vx`, `y += vy` - Add gravity: `vy += gravity_constant` - Fade out particles over time (reduce alpha) ## Optimization Strategies Only when asked to make the file size smaller, implement a few of the following methods: 1. **Fewer frames** - Lower FPS (10 instead of 20) or shorter duration 2. **Fewer colors** - `num_colors=48` instead of 128 3. **Smaller dimensions** - 128x128 instead of 480x480 4. **Remove duplicates** - `remove_duplicates=True` in save() 5. **Emoji mode** - `optimize_for_emoji=True` auto-optimizes ```python # Maximum optimization for emoji builder.save( 'emoji.gif', num_colors=48, optimize_for_emoji=True, remove_duplicates=True ) ``` ## Philosophy This skill provides: - **Knowledge**: Slack's requirements and animation concepts - **Utilities**: GIFBuilder, validators, easing functions - **Flexibility**: Create the animation logic using PIL primitives It does NOT provide: - Rigid animation templates or pre-made functions - Emoji font rendering (unreliable across platforms) - A library of pre-packaged graphics built into the skill **Note on user uploads**: This skill doesn't include pre-built graphics, but if a user uploads an image, use PIL to load and work with it - interpret based on their request whether they want it used directly or just as inspiration. Be creative! Combine concepts (bouncing + rotating, pulsing + sliding, etc.) and use PIL's full capabilities. ## Dependencies ```bash pip install pillow imageio numpy ``` ## When to Use This skill is applicable to execute the workflow or actions described in the overview.