plex-reencoder

Terminal version

+----+ > PLEX-REENCODER +-----------------------------------------------------+
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|                     ##...##. ##:      ##...... .##.##..                     |
|                     ######.. ##:      #####.    .###..                      |
|                     ##.....  ##:      ##....    ##.##.                      |
|                     ##:      #######. #######. ##.. ##.                     |
|                     ...      ........ ........ ...  ...                     |
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| ######. #######.#######.###.   ##. ######. ######. ######. #######.######.  |
| ##...##.##......##......####.  ##:##......##....##.##...##.##......##...##. |
| ######..#####.  #####.  ##.##. ##:##:     ##:   ##:##:  ##:#####.  ######.. |
| ##...##.##....  ##....  ##:.##.##:##:     ##:   ##:##:  ##:##....  ##...##. |
| ##:  ##:#######.#######.##: .####:.######..######..######..#######.##:  ##: |
| ...  ......................  ..... ....... ....... ....... ...........  ... |
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|         .:######################################################:.          |
|  > PLAY - EP 6:00:00                                      TRK ===..  * REC  |
+-----------------------------------------------------------------------------+

cat banner.ans in a 256-color terminal for the vibrant ANSI-colored version.

Bash tooling for surveying and re-encoding a Plex media library (NFS-mounted, <share-a> and <share-b> shares on an internal NFS server) down to space-efficient H.264/HEVC without a meaningful quality loss. Split out from a former monorepo that also contained the unrelated VHS digitization pipeline (vhs-cli, vhs-gui) — no relationship to those repos.

Hardware

Encodes run on the same Linux workstation as the VHS pipeline — AMD Ryzen 9 5900X (12-core). Re-encoding here is CPU-only (libx264/libx265 via ffmpeg); none of these scripts use the machine's GPU (AMD Radeon RX 7800 XT). Encodes stage to a local drive (/media/<user>/<external-drive>/Videos/plex_encode) before moving to an internal NFS server, which hosts the <share-a> / <share-b> media shares this tooling operates on.

Scripts

Script	Purpose
plex_space_survey.sh	Disk usage survey across the NFS-mounted library.
plex_probe_large.sh	ffprobes the largest files to find bloated/inefficient encodes (codec, bitrate, resolution, duration).
plex_find_dupes.sh	Detects likely duplicate movies via normalized directory-name matching.
plex_reencode.sh	The main re-encoder: Blu-ray rip/remux → H.264 CRF 20 (slow preset, capped at 1080p unless overridden), AAC stereo + optional 5.1, subtitle reorder by language preference. Stages to a local SSD before moving to NFS; auto-discards an encode that ends up larger than its source.
plex_cleanup.sh	Deletes media listed in a file. Dry-run by default; requires --confirm.
plex_swap.sh	Deletes the original .mkv and renames the matching .x264.mkv → .mkv in one step (the manual-cleanup step after plex_reencode.sh). Dry-run by default; requires --confirm.
reencode_barracuda.sh	Re-encodes high-bitrate files on the <share-b> share to HEVC in place: encode to local staging, verify (duration match, stream presence), copy back over the original, clean up staging.

All scripts log to ./logs/<script>_<timestamp>.log. The destructive ones (plex_cleanup.sh, plex_swap.sh) default to a dry-run preview and require an explicit --confirm flag to actually act.

Target bitrates (empirically validated)

For older films/TV (pre-2000s, sitcoms, dramas): 4–6 Mbps at 1080p via CRF 22 is a comfortable target — e.g. a 1984–85 sitcom season landed at 4–6 Mbps at CRF 22 from 15–20 Mbps sources (55–70% savings), visually fine.

• CRF 18 — near-lossless, ~8–20 Mbps output. Only worth it over an already-compressed source if that source is above ~12 Mbps.
• CRF 22 — good quality, ~4–8 Mbps output. Right for older/archive content.
• CRF 18 will bloat an already-moderate-bitrate H.264 source (8–12 Mbps) — the size check in plex_reencode.sh auto-discards these regressions.
• Worth re-encoding: source bitrate well above 8 Mbps for older content. Skip anything already at or below 6–8 Mbps.

plex_reencode.sh details

• Default CRF 20; override with CRF=22 ./plex_reencode.sh <list>.
• Auto-discards an encode if it ends up larger than its source.
• Stages to a local SSD (/media/<user>/<external-drive>/Videos/plex_encode) before moving to NFS — this is the scratch space for all encodes.
• Source .mkv → output .x264.mkv (original kept, needs the manual plex_swap.sh cleanup step); source .m2ts/.mp4 → output .mkv directly.
• FFMPEG_BIN=/usr/bin/ffmpeg (libx264), FFPROBE_BIN=/usr/local/bin/ffprobe.

Monitoring: tail the main script log, not the per-file _ffmpeg log —

tail -f logs/plex_reencode_<timestamp>.log

This shows item number, filename, SKIP reasons, stream selection, and scaling decisions. The _<N>_ffmpeg.log file has raw ffmpeg stderr for frame-level progress if needed.

NFS library

• Movies: /mnt/media/movies/<share-a>/ (canonical) and <share-b>/
• TV: /mnt/media/tvshows/<share-a>/ and <share-b>/
• Server: an internal NFS server

<share-a> content takes precedence over any <share-b>/migration duplicates when reconciling the two shares.