Ports bebop-2's working video.py, which was verified against the live
aircraft. Firmware 4.7.1 serves no RTSP, so there is no URL and no RTSP
path here: we describe our own receiving port in an SDP and let ffmpeg
bind it before VideoEnable goes out, because RTP is connectionless and
packets that arrive before the sink is listening are gone.
Three changes on top of the port. StreamSession no longer owns the drone
link, since the tools layer holds a long-lived session; it takes an async
sender callable instead, which also keeps media/ loadable while arsdk/
and protocol/ are still being written. The context manager is async for
the same reason, with the blocking subprocess waits moved off the event
loop. And downscale() shrinks a frame before it reaches a model, because
a full 856x480 is most of a context window spent on pixels nobody asked
for.
FTP exposes media (21), flightplans (61) and logs (21, scoped to the
Debug tree). Port 51 is deliberately absent: it serves /update as root,
it is how firmware is pushed, it has no read use case, and the drone's
Wi-Fi is open. Fetches stream to capture_dir under a size cap so a 1080p
recording cannot be pulled into a tool result.
The shell is an allow-list of eleven read-only command names rather than
a deny-list, because the login is `exec /bin/sh -l` with no password and
deny-lists on shells leak. Arguments carrying shell metacharacters are
refused before the socket opens. Output is bracketed between two echoed
nonce markers rather than trimmed by prompt pattern, since telnetd's pty
echoes our input with the prompt glued to the front and sends all of it
before anything runs.
protocol/types.py and arsdk/types.py are the interfaces the parallel streams
build against: command/arg/enum/expectation specs and the safety tiers on one
side, frame encoding and the buffer conventions on the other.
Logging goes to stderr throughout, since stdout carries JSON-RPC. That is also
why this package will speak ARSDK itself rather than through pyparrot, which
prints from its receive thread.
Bebop-era snapshot of common.xml and ardrone3.xml (BSD-3-Clause, Parrot SA),
with pyparrot's <myclass> rename reverted to Parrot's <class>. Provenance and
the comparison against upstream master are in arsdk-xml/PROVENANCE.md.
rsp2k