# Astra / Codex video-editing example

This self-contained technical example accompanies the Kingy.ai guide.
The source is eight seconds of a synthetic moving test pattern with a generated
440 Hz tone. It contains no real person or spoken dialogue.

Files:
- source/input.mp4: 640x360, 30 fps, eight-second source.
- outputs/test-cut.mp4: three seconds, starting two seconds into the source.
- outputs/test-vertical.mp4: centered 1080x1920 crop of the cut.
- reproduce.sh: commands to generate fresh versions without replacing references.

Open this folder in Codex and ask it to reproduce the edit using fresh filenames.
Alternatively, with FFmpeg and FFprobe installed, run `bash reproduce.sh` from
this folder. The script stops if its new output filenames already exist.

The reference outputs were produced using FFmpeg 8.1.1 on macOS. Both are three
seconds long, H.264 video with AAC audio, at 30 fps. Both decoded completely
without reported errors. No dialogue, lip-sync, captions, or storytelling quality
was tested. The vertical image is upscaled from a small source and is a crop
example, not a demonstration of enhanced image detail.

To create another synthetic source yourself (choose an unused output filename):

ffmpeg -n -f lavfi -i "testsrc2=size=640x360:rate=30:duration=8" -f lavfi -i "sine=frequency=440:sample_rate=48000:duration=8" -c:v libx264 -pix_fmt yuv420p -c:a aac -shortest source/another-input.mp4
