MLT XML Library for Kdenlive

A pure Python library for creating, modifying, and parsing MLT XML files compatible with Kdenlive.

Features

• Pure Python - No MLT framework dependency, direct XML manipulation
• Timecode API - All public methods accept HH:MM:SS:FF format
• Frame Alignment - Library automatically converts timecodes to frame numbers
• Media Management - Add/modify/delete audio/video files in the bin
• Timeline Editing - Add clips, tracks, filters, and transitions
• Subtitle Support - External SRT file references
• Kdenlive Compatible - Generates XML that Kdenlive can open

Installation

Using uv (recommended)

uv pip install mlt-python

Using pip

pip install mlt-python

For development

git clone https://github.com/gpapp/mlt-python.git
cd mlt-python
uv sync

Quick Start

from mlt_python import MLTProject

# Create a new project
project = MLTProject(profile="hd1080_30")

# Add media to bin
video = project.add_producer("video.mp4", id="vid1")

# Add a video track
track = project.add_track("video", id="playlist0")

# Add a clip using timecodes
project.add_clip(
    track_id="playlist0",
    producer_id="vid1",
    start="00:00:00:00",
    duration="00:00:10:00"
)

# Add subtitles from SRT file
project.add_subtitle("subtitles.srt", track=0, start="00:00:00:00")

# Save to file
project.save("project.kdenlive.xml")

Supported Operations

Producers (Media Bin)

• add_producer() - Add video/audio/image to bin
• remove_producer() - Remove from bin
• get_producer() - Get producer by ID

Tracks (Playlists)

• add_track() - Add video/audio track
• remove_track() - Remove track
• add_clip() - Add clip to track using timecodes

Filters & Effects

• add_filter() - Add filter to project/track
• Built-in filters: Filters.greyscale(), Filters.volume(), Filters.watermark()

Transitions

• add_transition() - Add transition between tracks
• Built-in transitions: Transitions.luma(), Transitions.mix(), Transitions.composite()

Subtitles

• add_subtitle() - Add subtitles from SRT file
• SRTFile - Utility class for reading/writing SRT files

Profile Presets

• hd1080_30 - Full HD 1080p @ 30fps
• hd1080_2997 - Full HD 1080p @ 29.97fps
• hd1080_25 - Full HD 1080p @ 25fps (PAL)
• hd1080_24 - Full HD 1080p @ 24fps
• hd720_30 - HD 720p @ 30fps
• uhd_30 - 4K UHD @ 30fps
• uhd_24 - 4K UHD @ 24fps
• sdtv_ntsc - SD NTSC 480i
• sdtv_pal - SD PAL 576i

Example

See examples/example.py for a complete example showing:

• Multiple video/audio tracks
• B-roll with transitions
• Audio mixing
• Subtitle integration
• Filter effects

Running Tests

uv run pytest tests/ -v

License

MIT License - see LICENSE file for details