Edit Decision Lists and Timeline Interchange

An edit decision list (EDL) is a text record of an edit: an ordered list of events, each naming a source reel or clip, the source timecodes to use and where they land in the finished program. Timeline interchange is the broader set of formats that move a whole edit between tools, including EDL, AAF, Final Cut Pro XML, FCPXML and OpenTimelineIO. None of them contains the footage itself. They describe how to assemble it, which is why a cut made in one application can be finished, graded, mixed or sent to visual effects in another. In post-production on film and television this has always mattered. It matters more in 2026 because a growing share of first cuts is made by software, including the tools of AI video editing, and then handed to a person to finish.

The Formats

Format	Origin	What it carries	Typically read by
EDL (CMX 3600 and variants)	Linear tape editing	One line per event: event number, reel, track, transition (cut, dissolve, wipe), source in and out, record in and out	Nearly every editor, color and VFX tool
AAF (Advanced Authoring Format)	Advanced Media Workflow Association; being standardized through SMPTE	Multitrack compositions and metadata, with media linked or embedded	Avid Media Composer, Pro Tools, most professional editors
Final Cut Pro 7 XML ("xmeml")	Apple's pre-2011 Final Cut Pro	Tracks, clips, transitions, basic filters, keyframed levels, markers	Adobe Premiere, DaVinci Resolve
FCPXML	Final Cut Pro (version 1.14 shipped with Final Cut Pro 12.0 in January 2026)	Final Cut's model: a primary storyline, connected clips, compound clips, roles, rich metadata	Final Cut Pro, DaVinci Resolve
OpenTimelineIO (OTIO)	Began at Pixar; now an Academy Software Foundation project	Tracks, clips with source ranges, gaps, transitions, markers and open-ended metadata, plus a C++ and Python API	DaVinci Resolve, Avid Media Composer, pipeline tools

The EDL is the oldest and the most limited. Wikipedia's summary is that CMX 3600 "can represent simple editing decisions only," and reel names are commonly limited to eight characters. It survives because nearly everything can read it, which makes it the default for handing shots to a VFX vendor or a colorist. AAF is the workhorse between picture editing and audio post, and the usual way a locked cut travels to Pro Tools. The two Final Cut formats are not related despite the name. Final Cut Pro 7 XML outlived the application that created it because Premiere and Resolve still use it, while FCPXML describes the very different timeline of the current Final Cut Pro.

OpenTimelineIO calls itself "an interchange format and API for editorial cut information" and is explicit that it "is not, however, a container format for media." Its adapter plugins translate to and from Final Cut Pro XML, AAF and CMX 3600 EDL, which lets it act as a hub between the other formats. The latest release is v0.18.1 (November 9, 2025). As of October 2026 the project is still at the "Incubating" stage at the Academy Software Foundation, with its next annual review due November 11, 2026. Avid's Media Composer 2026.8 (September 2026) updated its OpenTimelineIO adapter for "round-trip fidelity with third-party tools." Final Cut Pro has no native OTIO support and speaks FCPXML.

What Gets Lost

Every hop loses something, and knowing what is the difference between a smooth conform and a day of rebuilding:

• Effects and graphics. Titles, plug-in effects and most motion graphics do not survive outside their home application. At best they arrive as markers or placeholders.
• Reframing. Position, scale and crop, including automatic face-following crops for vertical video, are rarely carried faithfully and often have to be redone.
• Audio levels. FCPXML and Final Cut Pro 7 XML can carry levels and keyframes. OTIO's core schema has no volume field, so tools put levels in metadata that the receiving application may ignore.
• Speed changes. Constant speed changes usually translate, while speed ramps often do not.
• Transitions. Anything beyond a cut or dissolve tends to become a dissolve of the same length.
• Captions. These usually travel as a sidecar file, such as SRT, rather than inside the timeline (see auto-captions).

Split edits are a common test of a format. In a J-cut or L-cut the sound starts before or runs past its picture. EDLs struggle with these, while the XML formats and OTIO can represent them as separate picture and sound items.

AI First Cut, Human Finish

Interchange is how agentic video editing fits into professional work. An agent can log footage, assemble selects and build a rough cut from transcripts in minutes. Color, sound design and the final judgment about rhythm still usually happen in a Premiere or Resolve timeline. The hand-off has to be exact: every clip at the right source frame and every split edit intact. Tools built on video as code have an advantage here, because their edit already exists as a precise, frame-resolved plan that can be translated rather than reverse-engineered.

MetaRush, an AI video editing harness, works this way. It exports OpenTimelineIO, FCPXML and Final Cut Pro 7 XML from the same frame-accurate plan its renderer draws: OTIO for DaVinci Resolve, FCPXML for Final Cut Pro and the older XML for Premiere, with an SRT beside each for captions. Each export lists in plain words what the format cannot carry, such as reframing and the graphics MetaRush draws itself.

Choosing a Format

• To DaVinci Resolve: OTIO, FCPXML or Final Cut Pro 7 XML. Resolve reads all three, plus AAF and EDL.
• To Final Cut Pro: FCPXML.
• To Adobe Premiere: Final Cut Pro 7 XML or AAF.
• To Avid Media Composer or Pro Tools: AAF, with OTIO increasingly viable in Media Composer.
• To VFX or a colorist, shot by shot: an EDL, often alongside an XML for context.

Whatever the format, check the result. Compare durations and a few source timecodes against the original, and scrub split edits and transitions before handing anything on. Interchange files are text, so they can also be diffed and validated against the published schemas or DTDs, which is the same discipline non-destructive editing relies on.

Where It's Headed

OTIO is the format to watch. Its graduation out of incubation, broader native support and use by AI tools as their export format could make it the common layer that EDLs once were, with richer data. The comparison with FCPXML, the richest single-vendor format, is covered in OpenTimelineIO vs FCPXML. For VFX and virtual production pipelines, where editorial data feeds shot tracking and asset management, an open, scriptable timeline format is overdue.