fix(notebooks): play() emits even (h,w) so video plays in JupyterLab#29
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play() passed only height to mediapy.show_video and let it derive the
width, which could land odd. Odd dimensions cannot encode as yuv420p, so
browser-based JupyterLab refused to play the clip ("No video with
supported format and MIME type found"); VS Code tolerated it, so it went
unnoticed.
Compute an explicit even (height, width): cap height to the source (never
upscale), aspect-match the width, round both down to even. Pad the source
to even dims first, covering the case where mediapy declines to upscale a
tiny clip. Output now encodes as yuv420p and plays in all browsers.
Fixes #28
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Problem
The rendered-movie cells in the teaching notebooks (
01_anatomy.ipynb'splay(_frames4, …)cell and the same helper in02_demixing.ipynb) showed a blank video box reading "No video with supported format and MIME type found" when run in JupyterLab in a browser.play()passed onlyheighttomediapy.show_videoand let mediapy derive the width, which could land on an odd value. Odd dimensions cannot encode asyuv420p, so browsers refuse to play the clip. It went unnoticed because the notebooks were authored/run in VS Code, where playback is more permissive.Fix
play()now computes an explicit even(height, width):yuv420p-encodableThe source is also padded to even dimensions first, covering the case where mediapy declines to upscale a tiny clip.
Testing
(101, 99), odd-square(99, 99), even(100, 100), and large(600, 800)clips all resolve to even output dimensions and encode to valid HTML5 video.play(...)cells now render and play inline.Fixes #28
🤖 Generated with Claude Code
📚 Documentation preview 📚: https://minisim--29.org.readthedocs.build/en/29/