Documentation
README
render-cosmic-mythology-voiceover
Assemble a cosmic-mythology-voiceover reel from a config: a faceless, cinematic storytelling video where a warm, contemplative spoken voiceover carries the whole narrative (a "myth as teacher" reframe) over a slow, weighted Ken-Burns zoom across curated cosmic / mythology stills in ONE ethereal deep-indigo + gold look, with ONE on-screen hook line and burned captions. This capability is the FREE, deterministic assembly โ the weighted beat-sync sequencing, the Ken-Burns render, the concat, the VO composite, the hook overlay, and the caption burn.
scripts/config.example.json is the worked example (WishAstro "Saturn isn't your villain", ~31s
1080ร1920 9:16, 12 weighted Ken-Burns cuts); scripts/PIPELINE.md maps every config block to its
source step and scripts/README.md documents the free assembly.
Run
There is a single runnable script โ scripts/render.py (config-driven, ffmpeg + Pillow only, NO
API keys and NO drawtext/libass required):
python3 scripts/render.py --config config.json --vo working/vo2/vo_atempo.mp3 \
--stills-dir working/stills --out working/final.mp4 \
[--words working/vo2/words.json] [--endcard working/endcard.png]
This is the FREE, deterministic assembly stage โ it spends nothing. The paid inputs are
separate capabilities โ the spoken VO (create-vo-elevenlabs, ElevenLabs eleven_v3 from a
tone-tagged script, atempo time-stretched so the delivered duration sets the timeline) and the 4โ6
hero stills in one look pack (create-image-fal, Flux Pro 1.1, reused as repeats to reach the
~10โ12 cuts). Given the VO + the stills + the per-cut weight array + the hook line, render.py
distributes the cuts across the VO duration by the weighted formula, Ken-Burns-renders each still,
concats, composites the VO, fades the hook line on over the open, burns the captions, and (if
--endcard is passed) appends a brand end card โ the master + a poster. Re-cuts reuse the existing
VO / stills and cost $0. See scripts/README.md ยง0 for the full arg contract.
Contract (the free assembly)
- The spoken VO carries the narrative โ no talking head, no sung song. The generated/supplied VO IS the audio bed (no music bed by default); do not add a presenter or a second bed.
- Plan the timeline AROUND the delivered VO duration. The VO is atempo time-stretched (clamp the factor โค ~1.25 so the voice never chipmunks); its delivered length sets the timeline โ never trim the VO to a pre-planned grid.
- Weighted beat-sync, not a fixed grid. For each cut,
cut_dur = VO_dur ร weight / ฮฃweightsโ heavier weights hold longer on the emotional beats (the open, the reframe, the close); the setup cuts run shorter. Every cut stays proportional to the whole VO. - Ken-Burns per still. Render each still with scale 2ร, center crop, and a
zoompanto the configuredzoom_end(~1.10); applyzoom_outon the flagged cuts;fade_inon the FIRST cut andfade_outon the LAST. Stills are reusable โ the sequence repeats a few across the cuts. - ONE cosmic look, no in-world text. Every still reads in the single deep-indigo + gold + volumetric-light look; the reel's only text is the hook + the captions, added in post (the "no text, no words" descriptor keeps words off the stills).
- ONE hook line, alpha-faded on over the open. Burn the single reframe line over the OPEN only
(fade in ~0.5s, hold, fade out ~0.6s) โ never a persistent caption, never in-world.
render.pydoes this with a PIL PNG + ffmpegfade=โฆ:alpha=1(nodrawtextdependency, since stock ffmpeg often lacks it); an ffmpegdrawtextalpha window is an equivalent alternative where available. - Captions from Whisper โ bottom, white. VEED/Whisper subtitle burn tracks the spoken VO in the
bottom third, white
#FFFFFF. If the host ffmpeg lacks libass (nosubtitles/assfilter), render the cues as timed PIL PNG overlays (ffmpegoverlay=โฆ:enable='between(t,st,en)') at the same bottom placement โ a free local Whisper + ffmpeg burn is the fallback to the VEED tier. - FFmpeg composite, deterministic, FREE. ffmpeg-concat the Ken-Burns clips, composite the VO
under the picture (libx264
crf 18+ aac 192k), burn the hook alpha-fade + the caption track โ a 1080ร1920 h264+aac master (~31s). No paid calls, no keys (the local caption fallback is free).