MovFX

MovFX provides transition effects between images with optional sound.

Features

• 4 built-in effects: Fade, Dissolve, Wipe, Push/Slide
• Directional support for Wipe and Push (left, right, up, down)
• Optional sound overlay — audio duration drives the video length
• Smart duration resolution with minimum-duration enforcement
• Simple one-call API: create_transition()

Quick Start

from movfx import create_transition

# Simple fade transition (1 second, no audio)
create_transition("photo_a.png", "photo_b.png", "fade", "output.mp4")

# Dissolve with custom duration
create_transition("photo_a.png", "photo_b.png", "dissolve", "output.mp4", duration=2.0)

# Wipe with direction and sound
create_transition(
    "photo_a.png",
    "photo_b.png",
    "wipe",
    "output.mp4",
    direction="left",
    sound="music.mp3",
)

# Push/slide transition
create_transition(
    "photo_a.png",
    "photo_b.png",
    "push",
    "output.mp4",
    direction="up",
    duration=1.5,
)

Available Effects

Effect	Description	Extra Arguments
fade	Linear alpha crossfade	—
dissolve	Crossfade with per-pixel grain noise	grain_strength (0.0–1.0)
wipe	Hard-edge boundary sweeps across	direction (left/right/up/down)
push	New image slides in, pushing old image off-screen	direction (left/right/up/down)

Duration Rules

1. Default duration is 1 second
2. If the effect defines a minimum duration and the requested duration is shorter, the minimum is used (with a warning)
3. If a sound file is provided and its duration exceeds the requested duration, the sound duration is used (with a warning)

Installation

pip install movfx

Development

# Clone the repository
git clone https://github.com/mediatoolbox-org/movfx.git
cd movfx

# Create conda environment
conda env create -f conda/dev.yaml
conda activate movfx

# Install dependencies
poetry install

# Run tests
makim tests.unit

License

BSD-3-Clause