Matthew Jackson
99c5fd3500
The ReferenceBlock offset was computed for ANY video track, but the keyframe tick it measures against was recorded in a single global slot gated to the PRIMARY video track. On a title with two video tracks — an MVC base plus secondary view, or a multi-angle disc — a secondary track's non-keyframe therefore referenced a keyframe on a different track, or 0 (a self-reference) when the primary had not produced one yet. The tick is now recorded per track, so a non-keyframe can only reference a keyframe on its own track. The faststart moov-hole estimate modelled every audio track as (E-)AC-3 at 1536 samples per frame. 1.6.0 added DTS to the writer's carried set, and a DTS core AU is commonly 512 samples — a third of that — so a DTS track's sample table was under-reserved threefold and the mux fell back to moov-at-end, losing faststart on exactly the files 1.6.0 newly supports. mvc_frame_emits_blockgroup_additional_and_reference asserted only that the non-keyframe's ReferenceBlock was Some(_). Its non-MVC sibling, added in the same commit, pins the exact offset; this one now does too, so a mutant emitting a constant or wrong-signed offset no longer passes. The comment above the mp4 sample budget claimed file_len stops a crafted file inflating allocations "past the file's own size". Each indexed sample costs ~52 bytes, so the real ceiling is ~52x file_len (still capped by MAX_SAMPLE_COUNT). The bound is real; the comment overstated how tight it is.
libfreemkv
Rust library for 4K UHD / Blu-ray / DVD optical drives. Drive access, disc scanning, stream labels, AACS decryption, CSS decryption, KEYDB updates, and content reading in one crate. Drive-level unlocking is handled internally; consumers work with disc access and decryption only.
DVDs (CSS) decrypt out of the box. Blu-ray and UHD (AACS) require a keydb.cfg (default ~/.config/freemkv/keydb.cfg) supplying disc-specific volume unique keys; no AACS key material is compiled in.
12+ MB/s sustained read speeds on BD. Drive prep (init()) handles unlocking internally via the freemkv-unlock crate — clients never see it; when no drive unlock applies, the library rips via the host-certificate AACS handshake.
Multi-lingual by design — the library outputs structured data and numeric error codes, never English text. Build any UI or localization on top.
Part of the freemkv project.
Install
Consumed by git tag (not published to crates.io):
[dependencies]
libfreemkv = { git = "https://github.com/freemkv/libfreemkv", tag = "vX.Y.Z" }
Quick Start
use libfreemkv::{Drive, Disc, ScanOptions};
use std::path::Path;
// Open drive — identified via INQUIRY
let mut drive = Drive::open(Path::new("/dev/sg4"))?;
drive.wait_ready()?; // wait for disc
drive.init()?; // unlock + prep (handled internally)
drive.probe_disc()?; // probe disc surface for optimal speeds
// Scan disc — UDF, playlists, streams, AACS (all automatic)
let disc = Disc::scan(&mut drive, &ScanOptions::default())?;
for title in &disc.titles {
println!("{} — {} streams", title.duration_display(), title.streams.len());
}
// Stream pipeline — read PES frames from any source, write to any output
let opts = libfreemkv::InputOptions::default();
let mut input = libfreemkv::input("iso://Disc.iso", &opts)?;
let title = input.info().clone();
let mut output = libfreemkv::output("mkv://Movie.mkv", &title)?;
while let Ok(Some(frame)) = input.read() {
output.write(&frame)?;
}
output.finish()?;
Multi-pass recovery rip
Recovery moved OUT of this crate in 1.6.0. The sweep/patch strategy, the
ddrescue mapfile, damage classification and the multipass loop now live in the
freemkv-engine crate as freemkv_engine::recovery::{copy, sweep, patch}.
libfreemkv keeps the layers underneath: the raw single-shot read
(Drive::read) and the SCSI-fact translation (SenseFamily) that the engine's
strategy is built on. The dependency runs engine → libfreemkv, so this crate
cannot call into it; front-ends get recovery from the engine directly. See
docs/rip-recovery.md for what stayed here.
What It Does
- Drive access — open, identify, internal unlock + prep, speed control, eject
- 12+ MB/s reads — auto-detects kernel transfer limits, sustained full speed
- Disc scanning — UDF 2.50 filesystem, MPLS playlists, CLPI clip info
- Stream labels — 5 BD-J format parsers (Paramount, Criterion, Pixelogic, CTRM, Deluxe)
- AACS decryption — transparent key resolution and content decrypt (1.0 + 2.0 bus decryption)
- KEYDB updates — download, verify, save from any HTTP URL (zero deps, raw TCP)
- Content reading — adaptive batch reads with automatic decryption
- Stream I/O — unified stream pipeline for reading and writing any format
Streams
| Stream | Input | Output | Transport |
|---|---|---|---|
| DiscStream | Yes | -- | Optical drive via SCSI |
| IsoStream | Yes | -- | Blu-ray ISO image file (read via stream pipeline; written by freemkv_engine::recovery) |
| MkvStream | Yes | Yes | Matroska container |
| M2tsStream | Yes | Yes | BD transport stream with FMKV metadata header |
| NetworkStream | Yes (listen) | Yes (connect) | TCP with FMKV metadata header |
| StdioStream | Yes (stdin) | Yes (stdout) | Raw byte pipe |
| NullStream | -- | Yes | Discard sink (byte counter for benchmarks) |
Streams implement a single unified pes::Stream trait (re-exported as PesStream) exposing read() and write() on one type. input() / output() resolve URL strings to PES stream instances. All URLs use the scheme://path format — bare paths are rejected.
Keys
DVDs (CSS) decrypt out of the box, with no external key file needed.
Blu-rays and UHD (AACS) require a keydb.cfg at ~/.config/freemkv/keydb.cfg (or passed via ScanOptions). No AACS key material is compiled into the binary.
Architecture
Drive — open, identify, init, single-shot read
├── ScsiTransport — SG_IO (Linux), IOKit (macOS), SPTI (Windows)
└── unlock_bridge — private seam to the freemkv-unlock crate
(firmware / AACS cert / CSS bus-auth unlockers)
Disc — scan titles, streams, AACS/CSS state
├── UDF reader — Blu-ray UDF 2.50 with metadata partitions
├── MPLS parser — playlists → titles + clips + streams
├── CLPI parser — clip info → EP map → sector extents
├── IFO parser — DVD title sets, PGC chains, cell addresses
├── Labels — 5 BD-J format parsers (detect + parse)
├── AACS — key resolution + content decryption
├── CSS — DVD CSS (bus auth → player-key disc crack → known-plaintext title-key attack)
└── KEYDB — download + verify + save
Streams — unified PES pipeline
├── PesStream — pes::Stream: one trait, read()/write() PES frames
├── DiscStream — sectors → decrypt → TS demux → PES
├── IsoStream — ISO file → decrypt → TS demux → PES
├── MkvStream — MKV mux/demux
├── M2tsStream — BD transport stream
├── NetworkStream — TCP with FMKV metadata header
├── StdioStream — stdin/stdout pipe
└── NullStream — discard sink
See docs/ for detailed technical documentation on each module.
Error Codes
All errors are structured with numeric codes. No user-facing English text — applications format their own messages.
| Range | Category |
|---|---|
| E1xxx | Device errors (not found, permission) |
| E2xxx | Profile errors (unsupported drive) |
| E3xxx | Unlock errors (failed, signature) |
| E4xxx | SCSI errors (command failed, timeout) |
| E5xxx | I/O errors |
| E6xxx | Disc format errors |
| E7xxx | AACS errors |
| E8xxx | KEYDB update errors |
| E9xxx | Stream / mux errors (URL, PES, ISO, pipeline, demux) |
Platform Support
| Platform | Status | Backend |
|---|---|---|
| Linux | Supported | SG_IO ioctl |
| macOS | Supported | IOKit SCSITask |
| Windows | Supported | SPTI |
Contributing
Run freemkv info disc:// --share with the freemkv CLI to capture your drive's identity for contribution. Drive-unlock profiles are maintained in the freemkv-unlock repository.
License
MIT