Big Buck Bunny software streaming trial

This is a bounded playback baseline for the K230 shell. It does not claim a production video player, sustained 30 fps, audio support, or hardware decode. The board was operated by the primary agent; this evidence audit used only the provided transcripts and media.

Source and attribution

The stream was the public Akamai DASH manifest https://dash.akamaized.net/akamai/bbb_30fps/bbb_30fps.mpd, using Big Buck Bunny. The film is the Peach open movie by the Blender Foundation and is licensed under Creative Commons Attribution 3.0; attribution is retained here: (c) 2008 Blender Foundation / www.bigbuckbunny.org, official project attribution.

The trial worktree was at source commit 45e5e1a (Add a bounded software video probe and quiet radio logging). Playback used the target’s RISC-V mpv derivation with --vo=wlshm --hwdec=no --audio=no; the 270p launch also used --profile=sw-fast, --vid=6, --start=45, --length=30, and a 568x320 window. Audio was intentionally disabled. The source was remote DASH, so these results include network/cache behavior.

Results

The 640x360 trial selected H.264 video stream 7 (30 fps, 1255 kbps) and used wlshm software output. It recorded zero decoder drops and 509 video-output drops by the end of the bounded roughly 40-second observation, when playback was at about 1:09. The bounded run ended with Exiting... (End of file) after the requested 40 seconds; a concurrent DASH read reported Immediate exit requested during shutdown. This is a software-rendering stress result, not a claim that 360p is smooth.

The final 480x270 trial selected H.264 stream 6 (30 fps, 760 kbps), again with software H.264 and wlshm. It reached about 1:14 with 0 decoder drops and 106 video-output drops, and a final demuxer cache of about 96.97 seconds. The native screenshot 270p-native.png shows the decoded frame, launcher bar, terminal title, and keyboard.

The tested boot had only CPU 0 online and present. The CPU probe captured four complete process snapshots. CLK_TCK=100 and PAGESIZE=4096 were verified through the board console. Raw /proc samples are preserved in 270p-cpu-console.txt. Across the recorded interval, mpv advanced from 851 to 1,134 user ticks and 99 to 111 system ticks; Sway advanced from 650 to 740 user ticks and 86 to 93 system ticks. Using the recorded timestamps and CLK_TCK=100 gives a rough sampled average of 57% mpv, 19% Sway, and 76% combined CPU occupancy; this is an interval estimate, not a scheduler or whole-system benchmark.

The 270p status and the 360p status are preserved with terminal control sequences removed in 270p-final-status.txt and 360p-status.txt. The automated 270p physical camera trial was inspected before selection. The four-second cropped clip and still contain only the device display and no legs or other private scene content: 270p-physical-clip.mp4 and 270p-physical-frame.jpg. The crop was made from camera.mp4 with ffmpeg:

ffmpeg -ss 4 -t 4 -i camera.mp4 -vf crop=900:600:250:130 -c:v libx264 -pix_fmt yuv420p -an
ffmpeg -ss 5 -i camera.mp4 -frames:v 1 -vf crop=900:600:250:130

The camera media is not copied into the repository; the selected derivatives are the privacy-bounded evidence assets.

Limits

The status counters measure mpv’s decoder and video-output counters, not panel scanout or human-perceived smoothness. The native screenshot is a compositor capture, while the camera crop establishes physical display output but is oblique and not a readability calibration. The trial leaves network availability, DASH behavior, and the software-only decode path in the result.