Home Authoring and CBHD Reconstruction
Positions across the research passes
Home authoring is the most contested chapter in the CBHD record. Passes disagree on whether a disc burned on ordinary DVD media can play in a CBHD player. Summary:
| Pass | Position |
|---|---|
| ChatGPT pass 1 | No end user could author CBHD with typical DVD tools; ordinary PC DVD/Blu-ray burners cannot produce CBHD discs. |
| Claude pass 1/2 | No documented home method. Theoretical route blocked by FSM: no consumer burner writes FSM. Whether players read DVD-R with a CBHD folder structure is untested. |
| ChatGPT pass 2 | Separates three projects (CBHD-like disc, playable CBHD image, physical CBHD); physical CBHD needs FSM mastering. |
| Gemini | Practical pipeline: AVS via libxavs, LPCM/AC3, MPEG-2 TS mux, CBHD_TS tree, UDF 2.50 ISO burned with ImgBurn to DVD+R DL, claimed playable on Shinco HD-3700U or TCL THBD-1008. |
Gemini presents the pipeline as working, citing LDDb threads, What Hi-Fi, Wikipedia and general burning guides. Claude and ChatGPT passes found no documented case of a burned disc playing in a CBHD player and argue DVD burners write EFM+, not 4-6 FSM. Directory models also diverge (CBHD_TS vs EVOB/HD DVD Book 3).
Gemini pipeline (as stated)
Step 1 – encode strict AVS (GB/T 20090.2) elementary video with FFmpeg linked to libxavs, example constraints: ~15 Mbps average, maxrate 18M, closed GOP N=12 for 23.976 fps, Jizhun Base Profile Level 6.1, yuv420p. Commercial averages 12-18 Mbps sit under the CHDA 28 Mbps video ceiling.
Step 2 – audio: DRA via the Tsinghua thesis encoder if available; otherwise 16/24-bit LPCM or stereo/5.1 AC3/DTS for legacy decoder paths.
Step 3 – mux to MPEG-2 Transport Stream and lay out:
VOLUME_ROOT/
├── CBHD_TS/
│ ├── CBHD_TS.IFO
│ ├── CBHD_TS.BUP
│ ├── ITEM_001.AVS
│ ├── ITEM_001.MAP
│ └── MENU_01.AVS
└── ADV_OBJ/
└── CETC_NAV.DAT
Primary folder CBHD_TS (or HVDVD_TS on early CH-DVD transition discs) at volume root. CBHD_TS.IFO holds stream map, sector pointers, resolution and audio assignments; without it, players such as the HD-3700U may fall back to browsing an unparsed file structure.
Step 4 – build UDF 2.50 (or 2.01 with Unicode) ISO, uppercase ASCII volume label, burn at low speed to dual-layer DVD+R. Gemini states the pickup then reads the 0.6 mm layer, recognises UDF, finds CBHD_TS and plays through onboard AVS decode. HD DVD-R blanks are also listed among usable media in that account.
Directory model comparison
| Model | Top-level | Containers |
|---|---|---|
| Gemini | CBHD_TS/, ADV_OBJ/ | MPEG-2 TS/PS; .AVS, .MAP, .IFO/.BUP, CETC_NAV.DAT |
| HD DVD-derived | HVDVD_TS/, ADV_OBJ/ | EVOB / EVO (MPEG-PS) |
| Unknown | Requires real disc image | – |
Claude theoretical route (untested)
Encode with libxavs or AVC; audio AC-3 or thesis DRA; mux to EVO/program stream in HD DVD Standard Content style; build UDF 2.5 image. Blocker: pressed CBHD uses FSM and no consumer burner writes FSM. Whether players accept DVD-R media carrying a CBHD folder structure-analogous to HD DVD’s “3× DVD” method-is untested. That route would also need DKAA or an unencrypted mode players accept. The only documented realistic home-content route on original hardware remains USB file playback on the CBHD-9100 (1080p files, TS/MP4, external subtitles), with HD-3700U adding AVI and network shares.
Three projects that must not be conflated
| Project | Goal | Difficulty |
|---|---|---|
| A. CBHD-like video disc | UDF + compatible streams + simple navigation | Approachable once logical format is recovered |
| B. Playable CBHD image | Structure accepted by a real CBHD player | Hard (CETC + Book 2/3 details) |
| C. Physical CBHD | Data on CBHD physical media | 405 nm, NA 0.65, FSM, channel coding, replication |
VCD became accessible because its physical layer was standard CD. CBHD kept UDF, but its physical layer is not ordinary DVD burning.
Recordable CBHD (CBHD-R)
Patent CN101712809A describes an organic dye and recordable CBHD medium while calling commercial CBHD read-only replicated media. An AACS LA order form lists CBHD (China) Pre-recorded (P) and Recordable (R) options. Conclusion: recordable CBHD was technically contemplated; no evidence shows commercial CBHD-R discs, burners, recorders or consumer authoring chains shipped.
Reconstruction roadmap
- Known-good CBHD disc → sector image → UDF analysis → identify video-system files.
- Compare against DCA Book 3 assumptions → identify CBHD-specific extensions.
- Reconstruct unencrypted/non-protected test material.
Recommended order: obtain an inexpensive domestic disc; obtain two players (Shinco CBHD-9100 and TCL THBD-1008); identify optical chipset (Novatek parts, pickup, servo DSP, RF amp); dump firmware; make a physical-sector image (ordinary PC drives may not suffice); compare with HD DVD; identify an unencrypted or legally accessible sample; locate the DCA verifier; recover CBC/Memory-Tech authoring software; only then attempt home authoring. Before buying repair donors, photograph the pickup label. Untapped sources for disc-structure clues include the full AVSForum master thread and Wayback captures of Joyo-Amazon and Dangdang category pages.
Until a photographed successful burn-to-player test is published, treat Gemini’s DVD+R DL pipeline as an unverified recipe and treat FSM mastering as required for true physical CBHD.
Keeping the disagreement visible
Readers should leave this chapter knowing the research record does not agree. Gemini publishes a full command-line pipeline culminating in an ImgBurn UDF 2.50 burn to DVD+R Dual Layer and asserts playback on Shinco HD-3700U or TCL THBD-1008. Claude and ChatGPT passes found no documented successful burn-to-player case and emphasise that consumer burners write EFM+, not 4-6 FSM. Gemini’s cited sources for the pipeline are LDDb forum threads, What Hi-Fi, Wikipedia and general Chinese burning guides-not a photographed verification on calibrated hardware in the compilation passes.
Directory hypotheses also disagree. Gemini’s CBHD_TS with ITEM_001.AVS, MAP files and CETC_NAV.DAT differs from ChatGPT pass 2’s EVOB and HD DVD Book 3 model informed by DCA documentation. Claude presumed EVO containers from HD DVD lineage. None of the passes cites a directory dump of a real pressed CBHD disc. Home authors who pick one tree without imaging a commercial disc are guessing.
USB first, pressed media later
The only documented realistic home-content route on original hardware is file playback: CBHD-9100 USB for 1080p, TS and MP4 with external subtitles; HD-3700U USB AVI and Ethernet shares. Those paths exercise SoC decoders without claiming FSM authorship. They are the correct first experiment for anyone who owns a player and wants to see AVS on period silicon.
Recordable CBHD media remains a paper trail only: patent CN101712809A for dyes; AACS LA order-form categories for Recordable CBHD; zero evidence of shipped CBHD-R discs, burners or recorders. Listing HD DVD-R among Gemini’s usable blanks does not create a commercial CBHD-R ecosystem. Project C-physical CBHD-still demands 405 nm mastering, NA 0.65 optics, FSM channel encoding and replication know-how of the Memory-Tech/UOD class.
Reconstruction roadmap order from ChatGPT pass 2: obtain a cheap domestic disc; obtain CBHD-9100 and THBD-1008 players; identify chipsets; dump firmware; make a sector image; compare with HD DVD; find an unencrypted sample; locate the DCA verifier; recover CBC/Memory-Tech software; only then attempt home authoring. Skipping to step ten is how myths about burned DVD-9 CBHD discs spread.
Encoding constraints listed for hardware compatibility-closed GOP near twelve frames at 23.976 fps, Jizhun Base Profile Level 6.1, averages of 12-18 Mbps under a 28 Mbps ceiling-remain useful even if the burn step fails. They describe what commercial players’ ASICs expected. Falling back to LPCM or AC-3 when DRA encoders are unavailable matches player backward-compatibility lists. Multiplexing to MPEG-2 TS is consistent with one directory model; EVO/program stream muxing is consistent with another. Researchers should archive both experiment branches with clear labels rather than deleting the “failed” tree.
Project A (CBHD-like disc), Project B (player-accepted image) and Project C (physical FSM CBHD) must stay separated in grant proposals and lab reports. Conflating them produces blog posts that claim “CBHD authoring works” when only Project A file layouts were demonstrated-or when only USB file playback was tested. VCD’s accessibility came from CD physicality; CBHD kept UDF but not consumer-writable physics.
If a researcher follows Gemini’s ImgBurn steps and a player rejects the disc, record the exact on-screen error, whether the volume mounted as data, and whether CBHD_TS.IFO was present. If the player plays the disc, publish model number, firmware if shown, media type (DVD+R DL versus HD DVD-R), and a short video. Either outcome closes more science than another undocumented recipe. Until then, treat burned-media playback as unresolved per the open-questions list.
Further reading on historic video formats
If you want to learn more about historic video formats, get The History of Physical Video Formats from the Frontier by Stephen Driver on Amazon: