The software-fallback re-encode now runs deprioritized and admin-configurable.
The SW transcode ffmpeg child is niced (preexec_fn → os.nice, applied per-child
because the Popen lives in the long-lived API process, which must NOT itself be
niced — unlike the download worker's whole-process _deprioritize) so a CPU-bound
re-encode can't starve request handling or playback; the VAAPI path needs none of
it.
New sysconfig knobs (plex group, rendered on the admin Configuration page, i18n
HU/EN): plex_transcode_hw (auto/on/off, layered onto _want_hw), plex_transcode_
preset, plex_transcode_crf, plex_transcode_max_height (software-only downscale-to
cap; the GPU path encodes at source resolution). plex_max_transcodes stays the
concurrency cap (comment corrected — the fallback is shipped, not "later").
pytest extends the command-builder + _want_hw coverage (preset/crf/max_height
plumbing, the on/off/auto policy). Browser-UAT'd: max_height=240 drops the live
resolution to 330x240; the SW ffmpeg child runs at nice 10 (ppid=api process).
peter
ce96032edb