hive-kdenlive.mlt.model — io.github.hive-agi/hive-kdenlive 0.1.2

MLT document model: pure builders that produce xml.cljc node trees.

MLT's XML vocabulary, smallest useful subset: mlt root; LC_NUMERIC="C" so float serialization is locale-invariant profile frame geometry; the document carries one producer a clip source; resource lives in a property child playlist a track: <entry producer=.../> and <blank length=.../> refs tractor the timeline: <multitrack> of <track producer=.../> refs filter an effect on a producer/playlist/tractor transition a compositor between two tracks (a_track/b_track)

Builders return xml.cljc nodes; document assembles and xml/emit serializes. No IO, no host conditionals — core + string only.

aspect clj/s

(aspect width height)

[w h] reduced: the display aspect of square pixels at WIDTH x HEIGHT. A vertical 1080x1920 profile is 9:16; the profile default of 16:9 would tell a player to stretch it.

blank clj/s

(blank length)

A <blank length="n"/> gap in a playlist.

document clj/s

(document & children)

Assemble the root <mlt> node. children are profile, producers, playlists, tractor in emission order.

emit clj/s

(emit node)

Serialize a document (or any node) to an MLT XML string.

entry clj/s

(entry id & {:keys [in out filters] :as _opts})

A playlist <entry> referencing producer id, optionally cut by :in/:out. :filters (filter nodes) are nested inside the entry, so they act on this cut only. A nested filter's keyframes count from ITS OWN in, and its in/out are source frames like the entry's: give it in/out or its keyframes are read as source positions (measured 2026-09-15, melt 7.22).

filter clj/s

(filter mlt-service args & {:keys [id in out] :as _opts})

A <filter> node. mlt-service names the effect (e.g. "obscure", "volume"); args is a map of effect parameters, emitted as <property> children so any mlt-service parameter is reachable without per-effect code.

mlt-version clj/s

MLT version stamped on emitted documents.

parse clj/s

(parse s)

Parse an MLT XML string (kdenlive project file, melt output) into nodes.

playlist clj/s

(playlist id items)

A <playlist id=...> from a seq of entry/blank nodes.

producer clj/s

(producer resource & {:keys [id in out length ttl] :as opts})

A <producer> for resource (path/URL/color/...). opts: :id :in :out :length :ttl :properties (map of extra properties).

profile clj/s

(profile &
         {:keys [width height fps sar dar colorspace progressive]
          :or {width 1920
               height 1080
               fps 25
               sar [1 1]
               dar [16 9]
               progressive 1
               colorspace 709}
          :as _opts})

A <profile> node. opts: :width :height :fps [num den] :sar :dar :colorspace. fps may be a number (converted to the nearest standard fraction) or a [num den] pair for exact rates like [30000 1001].

properties clj/s

(properties m)

Map (or seq of pairs) to property nodes, in map order.

property clj/s

(property k v)

A <property name="k">v</property> node. Keyword keys lose the colon (:rect -> "rect"); v is stringified as-is.

qt-weight clj/s

(qt-weight css-weight)

The Qt5 weight for a CSS weight (100..900), rounding down to a named step.

rgba clj/s

(rgba colour)

"#rrggbb" or "#rrggbbaa" (CSS order, alpha LAST) -> "r,g,b,a", the colour spelling of a Kdenlive title. Not MLT's #AARRGGBB, where alpha comes first and "#ff0000ff" is opaque blue.

title clj/s

(title &
       {:keys [width height frames text font size weight color background align
               x y box-width]
        :or {font "DejaVu Sans"
             size 96
             weight 700
             color "#ffffff"
             background "#00000000"
             align :center}})

A <kdenlivetitle> node: one text block on a transparent (or :background) canvas of WIDTH x HEIGHT, FRAMES long. xml/emit it for the xmldata of a kdenlivetitle producer.

opts :text (newlines break lines) :font :size (pixels) :weight (CSS) :color :background ("#rrggbb[aa]") :align (:left :center :right) :x :y (top-left of the text box) :box-width Unset :y centres the block vertically, from the line count and 1.25 x size per line; unset :x and :box-width span the canvas, so :align decides.

title-producer clj/s

(title-producer title-xml frames & {:keys [id]})

A kdenlivetitle <producer> for title XML text, FRAMES long. The resource is empty, as in a Kdenlive project; the title lives in xmldata.

track clj/s

(track playlist-id & {:keys [hide] :as _opts})

A <track producer="playlist-id"/> reference inside a multitrack. opts: :hide (:audio or :video) mutes one leg of the track.

tractor clj/s

(tractor id tracks & {:keys [transitions filters] :as _opts})

A <tractor> timeline over tracks (track nodes), with optional transitions and filters appended after the multitrack.

transition clj/s

(transition mlt-service a-track b-track args & {:keys [in out] :as _opts})

A <transition> compositing b-track over a-track. mlt-service e.g. "mix" (audio) or "frei0r.cairoblend" (video).