Four audit rounds each fixed one rule in SeamPlan::place and broke another,
because the question the rules were answering has no answer. Inside a
seamless-branching overlap clip k OUT comes AFTER clip k+1 IN — 57.8s of
overlap on the real fixture table — so a single timestamp is legitimately
inside two clips, and a clip file is not trimmed to its marks, so it also
carries material from before its own IN. No rule over timestamps can say which
clip a frame came from, and each attempt was right for one disc layout and
silently wrong for another: 65s of rewind, 17 minutes stranded, 28 minutes
dropped, 55s refused.
Frames already carry the byte offset they were read from (PesFrame::source,
stamped by the TS demuxer). Clip now carries the byte span its stream occupies
in the title feed, recorded while the extents are gathered. So the clip is a
LOOKUP: the offset falls in exactly one span. There is no decision to get wrong.
Every track of a clip lives in the same stream file and therefore shares one
span, so video, audio and subtitles agree by construction. Divergence between
them — each track guessing separately under its own tolerance — is how audio
and video ended up on different clips and drifted apart in the first place.
spans_trusted gates the whole path: unless the spans tile the feed contiguously
from zero, an offset means nothing and provenance is ignored in favour of the
mark heuristics, which is the 1.6.0 behaviour. A broken map degrades instead of
confidently selecting a wrong clip for every frame. A clip referenced twice
reuses its first span (the bytes are read once) and is still trusted.
Sources that stamp no provenance — a mkv:// remux, the deserialize hop — take
the heuristics, which is what they have always used and where they have always
been right, because they have no overlapping clips to be ambiguous about.
36 timeline tests, six of them new and covering: the overlap case marks cannot
see, all tracks agreeing, out-of-marks material dropped AND counted, a holed
span map, a discontiguous one, a repeated clip, and no provenance at all.
Audit finding: both seam gates in MkvMuxer::finish were dead code under test.
set_clips was never called anywhere in the suite, so continuity.dropped_total()
was always zero and neither branch could be reached.
The ordering of the two zero-frame checks is load-bearing and the comment says
so: a title the seam plan emptied also has a zero frame count, and MkvInvalid
is classified by is_skippable_title_stub as an empty nav/menu stub — so
reporting it that way makes an all-titles rip drop a real feature and finish the
rest at exit 0. Swapping the checks left the entire suite green.
The new test builds a two-clip plan (from_clips needs at least two, strictly
increasing) whose marks exclude every frame, and asserts both that the error is
SinkWroteNothing and that it is NOT classified as skippable. Confirmed to FAIL
with the two checks swapped.
Four fixes from the first audit round. Every finding was verified against a
pinned tree and read directly before being accepted.
resolve_vts_key sorted a VTS title-VOB extents largest-first. That is the 1.5.1
garbage bug, and it grew back in a new code path: the comment claimed it
"matched the scan heuristic", but that heuristic WAS the bug and had already
been fixed in decrypt_keys_for_title, which documents the rule (PLAYBACK ORDER,
never largest-cell-first) and pins it with a regression test. A CSS DVDs biggest
cell opens with a long clear run and crack_key shares one sector budget across
the extent list, so starting there can exhaust it without ever MEETING
scrambled data — and CSS recovers the key from scrambled data itself. The crack
then returns None, the caller falls back to the disc-wide key, and every VOB in
that VTS is descrambled wrongly: corrupt PES behind an intact header, written
out as a complete extract at exit 0.
parse_pgcit dropped titles silently in THREE places — an unparseable PGC, an
out-of-range PGC index, and a truncated entry table. The finder caught one; the
other two turned up on reading the function. parse_vmg already counts and warns
per skipped title SET for exactly this reason, and this was the last place a
disc could quietly report fewer titles than it has.
write_image called flush() and returned Ok. flush() only pushes bytes into the
page cache and promises nothing about durability, so a 6-90 GB image could be
reported complete while still unwritten — a crash or an unmounted volume then
leaves a truncated file the caller was told was finished. Now into_inner (so a
buffered-write error surfaces instead of being dropped by BufWriter::drop)
followed by sync_all.
timeline used abs() on a saturating_sub result. Every other comparison in that
module is saturating because the timestamps come off a disc and are not
trusted; abs() panics on i64::MIN, which saturating_sub can produce.
The zero-frame check ran before the seam gate, and its error is
classified as a skippable nav stub — so a title the plan dropped
ENTIRELY was reported as an empty stub and an all-titles rip would omit
a real feature and finish the rest at exit 0. The seam case is decided
first now, with a code that is not skippable.
The demux sink read a frame's track kind out of the FILTERED slot, which
is empty for a class the export drops. On an audio:// or sub:// export
the video track was therefore called non-video and handed the permissive
crossing rule — the same defect round 4 fixed for a Dolby Vision layer,
reintroduced one file over. Video tracks are now recorded before the kind
filter, beside the primary-video reference that exists for this reason.
Its frame counter counted frames PLACED, not written, while its name and
doc claimed otherwise. Renamed and documented for what it is, including
that it cannot see a single lost track among many.
Placement: files in a subdirectory of VIDEO_TS were never given data.
They were declared at full size with no extents, so they appeared in the
tree and read as nothing. The same folder under BDMV was always placed
correctly. And the duplicate title-set guard keyed on the constraint maps,
so an IFO declaring no offsets inserted nothing and a colliding second IFO
went undetected — it keys on the groups seen now.
Display for SeamPlanDroppedMost and ShortImageRead discarded their
payloads, and four new variants were missing from the code-uniqueness
test.
Round 3 counted frames the clip marks excluded and reported them at
finish. Counting is not bounding: the only other gate was a global
zero-frame check, and its error is additionally classified as a skippable
nav stub, so a title whose marks do not line up with its PES clock could
discard almost all of itself and still exit 0 — a two-hour feature
emitting seconds, which is the defect this change set already shipped
once. Dropping more than was kept is never a real join, so it now fails.
The demux sink had no zero-output guard at all, so a fully-dropped title
finished cleanly: a directory of zero-byte track files beside a populated
chapters document. It now refuses, keyed on frames having been OFFERED —
a chapters-only export, or a track class the title does not carry,
legitimately writes none, and two existing tests correctly said so.
A title set's placement group is the parsed number, so VTS_01_0.IFO and
VTS_1_0.IFO land on one key and the second silently overwrote the first's
constraint, placing a VOB where the IFO the reader uses does not point.
Refused rather than resolved by arrival order.
A Dolby Vision enhancement layer is a second video track: it does not
drive epochs, but it does carry B-frame reorder. The crossing rule was
keyed on driving epochs, so the EL took the branch whose premise is that
the track has no reorder — and its ordinary reorder dip near the end of a
clip, which during an overlap also lands inside the next clip's range,
was read as a join. The EL was then placed on the next clip's offset, out
of step with the base-layer frame it must be co-timed with by the width
of the overlap: the same desync the per-track cursor was added to remove,
reintroduced for one track.
The property the rule actually depends on is whether a backward step can
be reorder, so it is now keyed on that. Both sinks derive it from the
track kind rather than from the epoch driver.
Two findings from the same escalation, both silent-wrong-output.
The plan was built for every multi-clip title. Only a Blu-ray PlayItem's
IN/OUT are positions in the clock the PES PTS runs on. HD-DVD fills the
same fields from the XPL's title-relative times and a DVD's come from
cell tables, so a plan built from them is an identity map with a drop
filter: it suppresses the layer-break rebase inference performs, and
drops whatever falls outside marks the PTS was never measured against. An
earlier reading of this called HD-DVD safe because its marks are
contiguous and every computed offset was zero — true, and irrelevant,
because they were zero in the wrong clock. Gated on the content format,
with a test using an HD-DVD-shaped table that the clock check alone
accepts.
The crossing test was also one-shot. A table whose clips restart their
own bases could miss it, and a missed crossing STRANDS the track: every
later frame falls outside the stranded clip's marks and is dropped for
the rest of the title. Counting drops, which is all the previous round
added, does not bound them. A table that is not one advancing clock is
now refused outright and falls back to inference, which is the documented
safe path for those titles.
Also from the same round: read_sectors added an unchecked lba + i, where
callers deliberately saturate their LBAs — a wrap folds the read back to
a low sector and hands the muxer another file's bytes. classify added 1
to two numbers parsed verbatim out of a filename. read_head used a single
read() where a short read on a network mount silently records no
placement constraint at all. And the page-cache eviction added last round
released only the read that crossed its threshold rather than everything
accumulated, so seven eighths of what was read stayed pinned.
The folder encryption probe returned "not encrypted" when it had sampled
nothing at all — a title shorter than one aligned unit skipped the loop
entirely. That verdict CLEARS the structural one an AACS directory
raised, so a genuinely encrypted folder would have been ripped as clear
and written ciphertext as video at exit 0. With no evidence it now keeps
the structural verdict, and its bounds arithmetic no longer trusts
disc-derived values not to wrap.
Reading an IFO header swallowed every I/O error and returned an empty
buffer, which sent each placement offset through unwrap_or(0) and
recorded no constraint at all — a permission error on one file produced a
silently misplaced VOB. The directory walk swallowed the same class while
claiming to skip only vanished files. Both now propagate; only NotFound
is skipped.
Four things the round-1 changes left inconsistent: two new error codes had
no doc comments, were absent from the io::Error mapping, printed no path
in Display, and were missing from the test that proves codes are distinct.
The demux sink dropped frames silently while the MKV muxer reported them.
And set_clips had been inserted INTO write_frame's doc comment, leaving
write_frame undocumented and its paragraphs describing the wrong function.
uid/gid used 0 as "not specified"; UDF's sentinel is 0xFFFFFFFF, and 0 is
root.
A sparse passive track — a subtitle with no event near a clip's mark —
was held to the dense-video crossing window, so it stayed on the previous
clip's offset until its PTS passed that clip's OUT and every event in
between was mistimed by the overlap. Video keeps the tight window,
because its backward steps are also B-frame reorder; passive tracks have
no reorder, so any backward step into the next clip's range is a join.
Frames the marks exclude were dropped without a trace. Dropping is right
at a join, but this codebase has shipped complete-looking wrong output
before, so the count is kept per track and reported when the mux
finishes, alongside the pre-cluster counter that exists for the same
reason.
A File Identifier Descriptor records its name length in one byte, and the
length was narrowed with a cast: a 255-byte name — POSIX NAME_MAX,
entirely ordinary — encodes to 256 and wrote zero, which would read every
later entry in that directory from the wrong offset. A directory's link
count is 16 bits and was computed as 1 + subdirectory count, which the
global entry cap alone permits overflowing. Both are refused while
planning, where the tree can still be rejected cleanly.
The module and struct docs described inference as the whole algorithm;
they now say which path decides what.
The first cut placed every track with the cursor the video had moved. At
an overlap join the previous clip's audio is still arriving after video
has crossed, and those tail frames sit inside both clips' mark ranges —
so they took the new clip's offset, jumped forward by the overlap, and
collided with the new clip's own audio, which the muxer's monotonic nudge
then flattened. A remux confirmed it: the timeline length was already
correct and the original symptom was still there, 169 audio packets on
the tick floor.
A track's PTS only runs forward inside a clip, so its own backward step
to the next clip's IN is its crossing. That is per track, so the cursor
is too.
A seamless-branching title's PlayItems do not chain contiguously: one
clip's OUT can sit after the next clip's IN, where the disc stores the
join twice, or before it, where the playlist skips material. The mux
never saw those marks — its own header said so — and inferred seams from
PTS jumps instead.
Inference cannot recover this. A forward jump is ambiguous: it means the
playlist skipped, or it means frames were lost to damaged media, and
compressing the latter would falsify timing on exactly the rips that most
need it faithful. An overlap smaller than the B-frame reorder threshold
is invisible to inference entirely, and its duplicate content then
collided in the muxer, where the monotonic nudge flattened a run of audio
onto the tick floor and put sound ahead of picture for the rest of the
film.
Measured on one 11-PlayItem title: the file declared 7893.385 s, which is
what the playlist says the title is, and carried packets to 8029.298 s.
Both numbers came from the same program on the same disc. Four skips
totalling 135.9 s became dead timeline, and a 1.79 s overlap put audio
1.8 s ahead at the half-hour mark. Five of forty-seven titles were
affected; every single-clip title was exact.
So the marks are read. Each clip contributes exactly out - in, laid end to
end, so the output runs as long as the playlist says and a join never
rewinds. Titles without usable marks — DVD, HD-DVD, file sources — keep
the inference path unchanged, and clips that already chain contiguously
produce a constant offset, which is pinned by a test.
Fifteen references across six files named the discs a defect was first
seen on. The parser leak found earlier was not an isolated slip — the
same habit runs through the mux comments, the changelog and the AACS
content verdict, where a title name was standing in for the shape of
the problem.
Every one is replaced with the property that actually mattered: a
multi-clip title, a UHD Dolby Vision profile 7 dual-layer stream, a
disc carrying an authored-bad TS packet. The comments are more useful
for it — the reader needs to recognise the shape on a disc they have,
not the one we happened to have.
`SEG_MainFeature` stays: the parser matches on that literal, so it is
a format token rather than a title.
The content-based forced-subtitle probe spent its whole 256 MiB budget
on the first sectors of a title. A feature's subtitles begin minutes in,
so the probe read the opening logos, hit the budget, observed no display
set at all and contributed nothing to any verdict — the vendor label was
always the only input.
The forced predicate is asymmetric: one non-forced display set disproves
forced permanently, while proving forced needs the whole track, and
genuine forced tracks are tiny where full tracks are huge. So the same
budget is now SPREAD over each extent in ~16 MiB windows placed on the
AACS unit grid, sized in proportion to the extent, ending at the extent's
end. Cost is unchanged; placement is not.
Also:
* Per-track early exit. A track that is disproven (and whose label
needs no correcting) stops asking for budget; an extent that owes
evidence only for such tracks is skipped outright, and evidence
already in the cache is never demuxed a second time.
* Content may now DEMOTE a wrong vendor forced flag, in the probe and
in the muxer, behind one shared guard: absence of forced_on_flag
only means something if some other track demonstrably uses it, and
the track must have the shape of a full dialogue track rather than
of a forced-narrative one. On a disc where no track sets the flag,
nothing is demotable.
* A sampled or budget-cut extent's evidence is memoised with the
COVERAGE behind it. It used to be filed under the extent's full key
and replayed to playlists that would have read far more of the clip,
turning a prefix into an absence claim about the whole extent.
A mutation run over mux/mkv.rs and mux/mkvstream.rs left 148 survivors.
Reading them turned up no wrong code, but a lot of code whose output
nothing ever looked at. Most of that is on the read side: parse_track
had a dedicated arm for Language, TrackName, FlagForced, Video and
Channels and not one of them was checked, so a re-mux could have lost
the audio language, the subtitle forced flag, every track label, the
resolution and the channel layout with the suite still green. Ten of
the eleven CodecID comparisons were unasserted too — only HEVC was
pinned — so any of them could have been mis-wired and the stream would
have gone to the wrong parser. The round-trip test now writes a real
three-track title through the muxer and reads it back through the
reader, and a separate test walks every registered CodecID.
The BPS statistics tag was the worst of the write side. Its test
asserted `file_bytes.contains("800")`, which a wrong bitrate passes
trivially — 80000 contains "800". Both the tag and the back-patched
Segment duration are now decoded and compared to a computed number, on
a title that declares no duration so the whole max_block_ticks →
seconds → bits chain is exercised. Cue points get the same treatment:
their CueTrack and CueClusterPosition were never read back, on either
the keyframe path or the i16-forced-split path, which are two hand-
written copies of the same three fields.
The rest closes arithmetic that only a bad disc reaches: a zero frame
rate or zero display-aspect denominator (both divisions), a
TimestampScale that does not fit an i64, a cluster timestamp of exactly
i64::MAX, a TrackNumber of 65537 that truncates onto the valid track 1,
and the shortest legal Block at both VINT widths. Two tests separate a
clean end of stream from a device failure: swallowing the second one
truncates the output at a bad sector and reports the rip complete.
Also pinned: only the first video and first audio track may be default
(the de-duplication lives in MkvStream::create and had no test at all),
the activation trigger is the first VIDEO track rather than track 0,
the measured field order reaches the file rather than just the helper
that computes it, and a Blu-ray 3D base/dependent pair builds the merge
instead of shipping two unrelated H.264 tracks.
96 of the 148 mutants verified killed by hand. Of the remainder, most
are equivalent — disjoint-bit `|` that `^` cannot change, delete-arm
mutants whose fallback is the same constant, guards on tracing calls —
and the write_frame branch at 1452 is unreachable: a cluster is always
open by the time it can be entered.
Every other repo's CI now runs clippy with --all-targets. libfreemkv,
the crate the other seven build against and the one held up as the
reference workflow, was the last one still linting the library only — so
its ~3,000 tests, by far the largest body of test code in the project,
had never been linted at all. Turning the flag on surfaced 74 findings.
Most were mechanical and applied with clippy --fix. The rest, by hand:
- Four discarded Results in decrypt.rs. css::descramble_region returns a
Result and four CSS tests threw it away, so a descramble that FAILED
would have surfaced as a confusing buffer-comparison mismatch instead
of the actual error. They expect() now.
- A dead `kp` field on the PlantedWalk fixture. The test deliberately
asserts Kp as the explicit AES-G3(dk, 1) relation from [C] §3.2.4
rather than against a stored value — its doc comment says so — which
makes the field not just unused but a trap: the obvious "fix" of
asserting against it would quietly weaken the test to comparing the
fixture with itself. Removed.
- Two hand-rolled ICB counters in the HD-DVD fixtures, a needless mut,
three vec!s that only ever needed arrays, a filter_map whose every arm
was Some, and a Vec::new()+push chain.
- Doc list indentation in mkv.rs and mp4/read.rs, which was mis-rendering
in the generated docs.
- A five-[u8; 16]-tuple return type named FourLevelParts.
Three lints are allowed at the specific sites, with reasons, because
they are wrong for this domain: the underscores in the bitstream-header
literals mark BITFIELD boundaries, not digit groups, so regrouping them
uniformly would satisfy the lint by destroying the only thing they
encode; and in three table-validation loops the loop variable is the
domain value under test (a DTS SFREQ code, an AMODE value, a palette
entry number), which is what the assertion messages name.
Resolution::pixels() returned (0, 0) for Unknown, and the MP4 sink wrote
it verbatim into tkhd (ISO/IEC 14496-12 8.3.2) and VisualSampleEntry
(12.1.3). Both fields are MANDATORY there, so unlike Matroska — which
omits the optional PixelWidth/PixelHeight elements — MP4 has nothing to
leave out. The result was a structurally complete file that passes every
container check, declares a 0x0 video track, cannot be rendered, and is
written with no error anywhere.
WHY IT WAS POSSIBLE, which is the part worth keeping:
pixels() previously fabricated 1920x1080 for Unknown. That was wrong but
playable, so this sink never needed a guard and the absence of one was
invisible. Changing the sentinel to (0, 0) moved the defect instead of
removing it — a zero PAIR still reads as a usable value, so the sink
stored it and serialised it.
The accessor's doc comment then ENUMERATED the callers it believed were
safe: "the Matroska sink omits the optional elements, the VobSub writer
omits its size: line, and no caller divides by either dimension." Two of
those three are true. MP4 was not on the list because MP4 has no guard
at all, and a prose list cannot enforce itself. mkv.rs's own comment
even states the principle — "the check belongs in the one accessor
rather than in each caller that remembered to write it" — and
labels/mod.rs still carried its own duplicate Unknown test long after
the accessor took that job over.
So: pixels() now returns Option. Not because Option is tidier, but
because every caller genuinely needs a DIFFERENT answer and the compiler
is the only thing that reliably makes them choose one. Matroska and the
metadata sinks take unwrap_or((0, 0)) with the reason stated at each
site; the VobSub path degrades to a palette-only .idx; MP4 fails with
E_MP4_UNKNOWN_RESOLUTION (9055).
Six call sites, not the five my first grep showed — I piped it through
`head` and acted on a truncated list. The compiler caught the sixth.
That is the same mistake as trusting a lens that reported silence.
Seven defects in the code the test suite executes least — 913 lines of
disc/mod.rs alone are run by no test at all, which is why this round scoped
from coverage rather than from what previous rounds said they had read.
Disc::scan_image kept its own copy of the crack's extent ordering and fed
crack_key_outcome largest-cell-first. That is the fifth instance in this
audit of a local reimplementation drifting from the canonical one, and the
cost here is a key that does not descramble the feature: picking by sector
count bypasses the capacity gate and can select a different VTS entirely.
The copy is gone — which title comes from the canonical order the scan
already applied, and the extents are handed over in playback order,
exactly as decrypt_keys_for_title does. Its doc records why the duplicate
existed so it cannot grow back.
Resolution::pixels returned 1920x1080 for Unknown. That is the FOURTH
instance of one trap and the other three were in this same file, two of
them fixed hours earlier — without sweeping for siblings, which is the
whole reason this one survived. It now returns (0, 0), and the sweep was
done properly this time: every remaining Unknown arm across the crate is
honest, and the two ColorSpace sites that look like fabrication are
emitting H.273 code point 2, which is the spec's own "unspecified". Two
callers carried local Unknown-to-zero workarounds — precisely the cost of
making callers responsible for a lie — and one is now redundant.
BD-ROM Part 3 code 0xA2 is the lossy secondary DTS stream, not lossless
Master Audio. A test asserted the wrong mapping as intended behaviour, so
correcting the code failed it; the test is deleted with a note pointing at
its replacement. That is a NEW failure mode for this audit: not a test
that cannot fail, but one that locks the defect in. There is no
DtsExpress variant to map to, so it takes the lossy DTS-HD member and the
approximation is documented.
Also: DiscSession::identify could panic through drive_mut once the public
API allows an absent drive — two siblings were converted in an earlier
round and this one was missed; an extent end that added without saturating
where the rest of the crate saturates; a diag reason string restating the
comparator's sort keys and drifting from them, now derived from them; and
a short read that advanced the offset by the full request, silently
skipping the gap. That last one existed twice, in two reads with the same
shape, now merged so they cannot drift apart.
The short-read policy is a judgement call I could not derive from a spec:
no skip_errors is a hard error, with skip_errors zero-fills and charges
the loss. It deliberately does not retry mid-unit, because resuming inside
an AACS aligned unit would trade a silent gap for a silent decrypt
desync — the worse of the two.
Three copies of the same two mappings existed. The canonical accessors
returned 6 channels and 48000 Hz for Unknown; a third copy in diag.rs
returned 0. The honest one was the copy.
A plausible wrong answer is worse than an obvious one. Six channels at
48 kHz is indistinguishable from a real 5.1 track, so every caller became
responsible for remembering to check the variant first — and this crate
walked into exactly that: the json:// sink reported a confident 5.1 for
audio whose neighbouring fields said "unknown". That was fixed at the call
site earlier in this audit; this fixes it at the source.
The accessors now return 0, which is what both in-crate call sites already
coerced Unknown to by hand, so their guards are gone and the behaviour is
unchanged. Zero is also obviously wrong if it ever reaches output, where
six is not.
The diag.rs duplicates are deleted rather than corrected — a fourth copy
would have drifted too. Their only caller was a trace line in the same
file, now on the canonical accessors. Their tests moved across and gained
the Unknown case, which is the point: restoring either fabricated value
fails both.
Found by the round-7 correctness agent while fixing the json:// sink; it
flagged the third copy as out of its scope rather than touching it.
Twenty-six confirmed findings from the fourth audit round, landed as one
cluster because they were found by agents working over disjoint file sets.
The one worth calling out is a pair of AACS tests that could not fail.
Both asserted CBC behaviour against a hand-rolled expectation that
happened to be IV-independent, so replacing AACS_IV with sixteen zero
bytes left them passing — they were pinning the code's own arithmetic,
not the published constant. Replaced with a literal witness of the
published IV plus the NIST SP 800-38A F.2.2 CBC-AES128 vector, and
verified the other way round: zeroing AACS_IV now fails three tests.
The rest are allocation and correctness work on hot paths: the Annex-B
writer in demux_sink allocated and freed a whole-frame Vec per frame,
which for a UHD title is ~200,000 allocations over the mmap threshold
plus the page faults to first-touch each one; it now reuses a buffer on
the writer, and still takes the NAL prefix width from the configuration
record rather than assuming four.
Six findings whose real fix lives in a consumer crate are recorded for
re-filing rather than patched here.
The Windows UI needs current winsafe, whose real minimum is 1.89 (its manifest
under-declares 1.87 while it uses NonNull::from_ref). Rather than stop at the
minimum, this goes to current stable and fixes what that costs.
The counter-intuitive result: 1.97 is CHEAPER than 1.89. libfreemkv had 54
clippy errors at 1.89 and 6 at 1.97, because clippy tightened the noisy
collapsible_if lint in between. Stopping at the minimum would have been the most
expensive choice available.
Roughly 47 lints across the eight repos, the large majority auto-fixed:
libfreemkv 6, freemkv-engine 14, bdemu 8, freemkv-keysources 7, autorip 6,
freemkv-unlock 3, freemkv-i18n 3. The hand-fixed ones are a descending sort to
sort_by_key(Reverse), four manual checked-division sites, a loop counter replaced
by enumerate, and a loop whose first let-else became a while-let.
Worth recording for whoever bumps next: clippy is MSRV-AWARE. Those 54 lints only
appear once the crate DECLARES 1.89 or later, because let-chains become
available. A bare `cargo +1.89 clippy` against a manifest still pinned at 1.87
reports clean and is meaningless — gate with the real precommit script, which is
also the only thing that covers build scripts.
The pin still sits below the Mac default, so it keeps doing its job: catching
lint drift locally before CI sees it.
**dec3 declared a 0 kbit/s AC-3 substream.** parse_dolby routes bsid < 11 to
parse_ac3, which leaves data_rate_kbps = 0 and keeps the AC-3 bsid, yet
dolby_sample_entry wrapped that config in ec-3/dec3 for any Codec::Ac3Plus track.
ETSI TS 102 366 Annex F.4 assigns ac-3/dac3 to an AC-3 bitstream and F.6 assigns
ec-3/dec3 to an Enhanced AC-3 one, so the entry now follows the SYNCFRAME that was
actually parsed, not the playlist's codec label. Computing an AC-3 data rate and
keeping ec-3 was rejected: it fixes one field while bit_stream_identification and
num_dep_sub keep misdescribing the stream. The bsid threshold is hoisted into one
constant so parser and entry-chooser cannot drift. Adjacent defect fixed in the
same box: data_rate is 13 bits from a u16 source, so push's mask WRAPPED anything
above 8191 (9000 became 808); it now saturates.
**colr tagged HLG as PQ, and PAL as BT.601.** video_colr carried a second,
drifted copy of the ColorSpace-to-CICP map: transfer 16 (PQ) for every BT.2020
stream with no HdrFormat override, and 6 (BT.601) for Bt470bg. Per ITU-T H.273
Table 3, HLG is 18 and BT.470-6 System B/G is 5 — and mkv::cicp_for_video already
got both right. video_colr now delegates to that shared resolver, so the
duplicated table is gone and cannot drift again. It keeps only its own decision
about WHETHER to emit the box, since an absent colr and an all-unspecified colr
mean the same thing per ISO/IEC 14496-12.
**Exact 24.000 / 30.000 / 60.000 fps was declared 23.976 / 29.97 / 59.94.**
detect_rate took the FIRST STD_RATES entry within 0.5 fps, and every 1000/1001
entry precedes its integer twin 0.024 fps away — a 0.1% error across the whole
track's mdhd and stts. Fixed as nearest-wins rather than by reordering the table:
reordering fixes today's table and re-breaks the moment someone appends a rate,
while nearest-wins is order-independent. Verified red here independently by
reverting to first-match, which fails exactly the two timing tests.
**ddts MultiAssetFlag was set from has_extension.** In the DTSSpecificBox
(ETSI TS 102 114) that flag signals more than one audio ASSET. A DTS-HD MA/HRA
track is one asset whose extension substream carries the XLL/XBR component, so
setting it from "an EXSS sync follows the core" sent a parser looking for a second
asset descriptor while StreamConstruction simultaneously said there was no
extension — the box contradicting itself. This module parses the core header only
and never reads the EXSS asset table, so 0 is the only honest declaration. A
StreamConstruction index for core+EXSS was deliberately NOT invented: that field
is a table lookup that could not be confirmed against the standard, and a wrong
index is worse than an under-declaration.
DTS_AMODE_LAYOUT's masks were independently re-derived against ETSI TS 102 114
§5.3.1 and all 16 are CORRECT — only three adjacent comments were wrong (the
AMODE 2/3/4 annotations were rotated by one, and AMODE 9's said "5.1 with LFE"
when 0x0007 is the 5.0 mask and LFE is OR'd in separately). Comments corrected.
Every one of the eight new tests decodes the field back OUT of the emitted bytes —
data_rate from the dec3 body's leading 13 bits, MultiAssetFlag from bit 48 of the
ddts tail, colr from the nclx payload inside a real stsd, and the frame rate from
mdhd.timescale plus stts.sample_delta of a fully muxed MP4 — rather than
restating arithmetic. This audit has already caught one of my own tests doing the
latter.
NOT fixed, root-caused and recorded at the site instead: an A_PCM/INT/BIG track
ships with no BitDepth, which the Matroska Codec Specifications make a MUST. The
width exists on disc (BD LPCM signals it in the ES header byte 3, DVD in the IFO
audio attribute byte 1) but neither source reaches MkvTrack::audio, and the fix
needs a new AudioStream member plus a deferred setter in files another agent held
this round. Guessing 16 was rejected — it would confidently misdecode every
24-bit disc — as was refusing the track, which would regress the 16-bit majority
that currently plays by accident.
Every BlockGroup frame back-patched its element size via ebml::end_master, which
does two stream_position() calls and two real seeks. BufWriter does not override
Seek::stream_position, so each position query is seek(Current(0)) = flush_buf +
lseek — and each of those flushed the 4 MiB BufWriter while every position-moving
seek reset WritebackPipeline::last_flush_pos. The buffer never got to do its job.
An MPEG-2 title takes this path for EVERY frame (the parser stamps a per-frame
duration, so I, P and B all become BlockGroups) — roughly 350,000 per feature.
A BlockGroup's size is knowable before writing, so there is no need to back-patch
at all. New seek-free twins start_master_buf / end_master_buf patch a placeholder
by buffer INDEX instead of file offset, and build_block_group assembles the whole
element into a persistent buffer that write_block_group and its MVC sibling take,
fill, write once, and hand back — including on the error path — so the allocation
is made once rather than per frame.
Measured with a counting writer that, like BufWriter, does not override
stream_position, over 200 frames:
seek calls position-moving
plain before 912 451
plain after 112 51
MVC before 2516 1253
MVC after 116 53
Per-frame cost is now zero; the residual is the header, the per-cluster
back-patch and Cues. For 350k BlockGroups that is 1.4M seek calls removed on the
plain path, 4.2M on an MVC title.
end_master is deliberately NOT changed for its other callers. The Cluster master
genuinely streams — frames are appended to an open cluster over time, so its body
cannot be buffered without holding a whole cluster in memory — and the rest
(EBML header, Tracks, Info, Chapters, Cues) run once, not per frame.
Byte-identity is the safety property, and it is structural: end_master always
patches a FIXED-width 8-byte VINT, and the buffered pair writes and patches
exactly that same placeholder, so the encodings cannot differ. Verified by
capture-then-compare over 200 frames (17 keyframes / 183 non-keyframes, multiple
clusters, BlockDuration present and absent, both reference branches) — output
byte-for-byte identical.
Three tests now pin it permanently: buffered vs seeking output byte-for-byte for
empty/tiny/multi-byte bodies, the same for NESTED masters (the MVC path nests
BlockAdditions > BlockMore, where an index-arithmetic slip would surface), and
end_master_buf erroring rather than panicking on a position outside the buffer.
All three verified red against a deliberately divergent placeholder width.
A note on verifying this kind of change: comparing emitted MKV across two
worktrees at different commits shows a spurious 14-byte difference, because
MuxingApp/WritingApp embed the build's git SHA twice. Compare at the same base.
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.
MkvTrack::audio's catch-all was `_ => CODEC_AC3`, and ebml.rs defined no
A_AAC, A_MPEG/L2, A_MPEG/L3, A_FLAC or A_OPUS constant at all. A CodecID
names the payload, so any of those codecs was written into the MKV declaring
AC-3 while carrying something else — a player either refuses the track or
decodes noise.
Reachable through two ordinary paths, both verified: ifo.rs:577 maps DVD
audio_coding_mode 3 to Codec::Mp2, so a DVD with MPEG audio muxed to mkv://
produced a track declaring A_AC3 over MP2 bytes; and mp4/read.rs:479 maps the
`mp4a` sample entry to Codec::Aac for an mp4:// source. codec/mod.rs already
has working parsers for MP2, MP3, AAC, FLAC and Opus, so the pipeline carried
these codecs end to end and only the container label was wrong.
MkvTrack::video had the same shape: `_ => CODEC_MPEG2` announced Codec::Mpeg1
and Codec::Av1 as MPEG-2 video. V_MPEG1 and V_AV1 added.
Both catch-alls stay, because MkvTrack::audio/video return Self and have no
error channel, but they are now reachable only by a non-audio/non-video or
Unknown codec routed there in error. Two tests enumerate every real codec of
each kind and cross-check each against Codec::kind(), so a codec added to the
enum later cannot silently inherit another codec's ID.
Both proven red first: Aac declared A_AC3 before the fix.
Two tests checked only find_id(&data, ebml::REFERENCE_BLOCK).is_some().
ReferenceBlock's EBML ID is the single byte 0xFB, so that asks whether one
exists ANYWHERE in the output — not which blocks carry one. Inside a
BlockGroup, keyframe-ness is signalled by the ABSENCE of ReferenceBlock, so
"which" is the entire question.
Measured rather than assumed. A mutant emitting a ReferenceBlock on every
BlockGroup, keyframes included — which reintroduces the exact 1.6.0 defect
these tests were added for, every frame reading as a non-keyframe — passed
mvc_frame_emits_blockgroup_additional_and_reference untouched. The
duration-bearing roundtrip test did catch it, via its MkvStream read-back
rather than via the presence check. A mutant corrupting the offset VALUE
was invisible to both.
all_block_groups() parses every BlockGroup in emission order with its
Block flags, relative timestamp, duration and decoded signed ReferenceBlock.
first_block_group() now delegates to it, so there is one walker rather than
two. Both tests assert per block: the keyframe carries NO ReferenceBlock,
each non-keyframe carries one, the offset equals the distance back to the
keyframe, and the SimpleBlock-only 0x80 flag is clear throughout.
Both tests previously took muxer.writer.into_inner() WITHOUT calling
finish(), leaving cluster sizes unwritten — an unparseable file, which is
why they could only byte-scan in the first place. They now write through
SharedWriter and finish(), so the assertions run against a well-formed
Matroska file.
Verified: with the fixes in place, the every-block mutant and the
off-by-one-offset mutant both fail.
Inside a Matroska BlockGroup the SimpleBlock 0x80 keyframe bit is
reserved and is always written as 0; keyframe-ness is carried only by
the presence or absence of a ReferenceBlock child. Both halves of the
round-trip got this wrong:
- the reader skipped past ReferenceBlock and read the reserved bit,
so every BlockGroup frame came back as a non-keyframe;
- write_block_group discarded its `keyframe` argument and never
emitted a ReferenceBlock, on the assumption that only intra frames
(PGS subtitles) reached that path.
The MPEG-2 parser stamps a per-frame duration on I, P and B pictures
alike, so all MPEG-2 video is written as a BlockGroup. That makes the
assumption false and left no video frame looking like a keyframe on
read-back. Downstream, mkv:// -> m2ts:// dropped every video frame (the
TS muxer discards non-key video until the first keyframe) while still
reporting success, and mkv:// -> mkv:// and the stdio round-trip failed
E6008, because the MKV muxer opens a cluster only on a track-0 video
keyframe and so wrote nothing at all. HEVC was unaffected: it carries no
per-frame duration, so it takes the SimpleBlock path where the flag bit
is authoritative.
Verified on a real CSS DVD: 841 keyframes out of 11440 video packets
survive a re-mux, matching the I-picture count in the source bitstream.
Also stop running non-NAL video through the Annex-B converter. MPEG-2
and VC-1 elementary streams are already start-code framed, so
length-prefix conversion corrupts them. TsMuxer takes a per-track
nal_video flag, defaulting to the previous behaviour, which M2tsStream
sets from each video stream's codec.
mp4 demuxer (untrusted input): bound every allocation sized from a box
field (stsz/stco/stsc counts, stts/ctts run-lengths, per-sample and moov
sizes, plus an absolute cap so a sparse file can't inflate file_len);
guard the parse_stsd slice and a zero mdhd timescale; cap track count so
the per-track PID can't overflow; rewrite read_moov to handle size==0 /
size<8 / 64-bit largesize; parse esds/AudioSpecificConfig for AAC; write
tkhd duration in the movie timescale.
decrypt: resolve_mux_key_map now fails loud on an extent no key can
classify instead of inheriting the previous extent's key, so a keymap
never silently carries a wrong key; the sweep/patch key-fetch recovery
fails loud when a unit is still unresolved after the retry.
AACS: reject inverted forensic segments in both range builders; compare
the forensic index in u16 space so an out-of-range value can't truncate
onto a valid u8 index. RECOVERED_ERROR no longer latches the damage zone,
preserving the 30s wedge cooldown for a following hard error.
audio: AAC/MP2/MP3/FLAC carry the last PTS across a PES with no timestamp;
the DTS-HD extension-sync search is bounded to after the core; the MP4
16.16 sample-rate field saturates. demux_sink records the video reference
before the kind filter so audio:// / sub:// keep multi-clip PTS continuity
and the DELAY tag.
Remove a dead error variant and the AACS-unsupported-video code; codec
comments cite the primary format specs; assorted doc/naming fixes and
regression tests throughout.
Give `info` the same forced-subtitle verdict the muxer derives during a
rip, so the two agree. A shared classifier (mux::codec::pgs::ForcedTracker)
folds a PGS track's display sets — forced iff every one carries the
forced_on_flag — and is used by BOTH the MKV writer and a new scan-time
probe that reads the title's PGS streams (reusing the TS demuxer and PGS
parser). The probe only overrides a track it actually observed content
for, so an undecrypted/unread stream keeps its vendor-derived flag. Gated
behind ScanOptions::probe_forced_subtitles (off for the rip path, which
detects forced while muxing without a second read).
Flag a PGS subtitle track FlagForced when it displays subtitles and every
one carries the HDMV forced_on_flag (a dedicated forced/narrative track),
independent of the disc's vendor label metadata. The track header
reserves a FlagForced byte up front and it is promoted at finish() from
the accumulated display-set state. Only ever promotes — a track already
forced from the playlist metadata is never demoted.
decrypt:
- decrypt_sectors is now a pure decrypt (apply key, leave plaintext, report
unverified bytes); TS-structure is a separate primitive (is_clean_ts/ps) used
only for key selection and read-verify. The mux passes decrypted bytes through
(the demuxer drops non-conforming packets), ending the NULL-TS conceal loop and
the per-unit key-server refetch storm. Key-proof floor replaces the 75%
supermajority.
recovery:
- Removed the post-read decrypt-verify gate (verify.rs) that mis-aligned the
disc-absolute unit grid against clip-anchored AACS units and false-failed good
clips (e.g. Dunkirk's orphan-CPS clip). Bad sectors are marked by physical read
result; decryptability is proven at scan + mux time.
HD DVD (first-class AACS):
- Role-based candidate-list file sourcing so an HD DVD's /ANY!/ files
(MKBROM.AACS, VTKF000.AACS, CONTENT_CERT.AACS) are found with no disc-type
branch. parse_vtkf parses VTKF000.AACS into the same UnitKeyFile as a BD
Unit_Key_RO.inf, so the shared VUK unwrap applies unchanged. set_unit_base
clip-anchoring. Two decrypt-axis assumptions remain UNVERIFIED-HDDVD-DECRYPT
(no encrypted disc to test).
mux:
- MVC (Blu-ray 3D) track signals unified into one MVCDecoderConfigurationRecord;
release-safe track_vint (3-byte VINT) and pid_index (i32) guards.
hardening:
- Container-aware is_clean / encryption detection; bytes_bad_in_title fail-safe
on a corrupt mapfile; CSS crack gated on DiscFormat::Dvd (HD DVD excluded);
non-vacuous CSS tests; patch NOT_READY/HARDWARE/ILLEGAL_REQUEST/ABORTED
sense-path tests.
AACS content decryption rejected a whole 6144-byte aligned unit unless
EVERY content packet was conformant MPEG-TS. One authored-bad packet (a
pressing/encoding defect or an AACS 2.1 forensic-variant frame) made the
mux conceal the entire unit as NULL TS — destroying up to 31/32 good
packets and tallying them as loss, surfacing as false "corruption" on
otherwise-clean discs (observed across two UHD titles).
decrypt_unit now asks only "did a key OPEN this unit?" — a padding-aware
>=75% supermajority of content packets restoring their 0x47 sync, a gate
no wrong key can reach (uniform-AES noise floor) yet one that tolerates a
minority of authored-bad packets. Opened units pass through VERBATIM; a
non-conforming packet is left for the demuxer to drop on sync-loss and
resync past. TS-sync conformance is a muxer concern, never a decryption
verdict. The post-read verify/sweep gate now shares the same primitive so
it can never disagree with the mux decrypt.
Also unify the MVC (Blu-ray 3D) track signals: the mvcC CodecPrivate
extension, the BlockAdditionMapping, and each per-frame BlockAdditional
all derive from one MVCDecoderConfigurationRecord built once per track, so
a malformed dependent-view parameter set can no longer orphan a BlockAddID.
Triage of a 10-lens code audit of the 3D branch. Fixes for real defects;
rejected three spec false-positives that matched the ISO/IEC 14496-15
§7.6.2 record verbatim.
Robustness / correctness:
- Never panic when a title's only video is the MVC dependent view: the
base is now the first NON-dependent video, so a dependent-only title
sets up no merge (muxed as an ordinary track) instead of hitting an
`expect` on the skipped track slot.
- Drop a per-frame BlockAdditional (BlockAddID=2) when the track declared
no mvcC mapping (dependent params not captured before the header) — a
plain block keeps the file conforming instead of an orphaned add.
- A non-keyframe MVC base frame always carries a ReferenceBlock (fall back
to a 0 offset in the pre-first-keyframe corner) so it is never mistaken
for a seek point.
- Reference the last keyframe on the PRIMARY video track only, so a
secondary video track's keyframe can't become a cross-track reference.
- dep_by_pts overflow: bound BEFORE inserting so the just-arrived
dependent survives the drift-clear; count a displaced duplicate-PTS
dependent as an orphan instead of losing it silently.
API / docs:
- Fold write_frame_with_additional into write_frame(..., Option<&[u8]>)
per the "no foo_with_X" convention.
- Fix mvc_params doc (StereoMode is intentionally not emitted); remove a
stale PAT/PMT comment describing an approach that was never taken.
Tests: MVCDecoderConfigurationRecord over-length guards; write_int minimal
two's-complement widths; BlockGroup/BlockAdditions/BlockAdditional +
ReferenceBlock emission; additional dropped without a mapping; h264 MVC
passthrough keeps param sets in-band; extract_mvc_params no-panic on
truncated/empty input; pairing window + dep-overflow edges; no-panic on a
dependent-only title.
Fold the MVC dependent (right-eye) view into the base H.264 track as a
per-frame BlockAdditional under an mvcC BlockAdditionMapping, so a 3D
title produces one MVC video track instead of two independent H.264
tracks.
- h264: MVC-passthrough parser mode keeps the dependent view's subset
SPS/PPS in-band, so each emitted frame is a self-contained dependent
access unit for a BlockAdditional
- resolve: route the dependent stream through the passthrough parser
- mkvstream: detect the dependent view, pair it to the base frame by
PTS (bounded FIFO), attach it as a BlockAdditional (BlockAddID=2),
and skip building its own track; build the mvcC
MVCDecoderConfigurationRecord from the captured subset SPS/PPS and set
it on the base track at activation
- mkv: emit the mvcC BlockAdditionMapping and BlockGroup/BlockAdditions,
with a ReferenceBlock on non-keyframe base frames
- ebml: add BlockAdditions/BlockMore/BlockAdditional/BlockAddID/
BlockAddIDValue/ReferenceBlock elements and a signed-int writer
Verified against a Blu-ray 3D ISO: ffprobe shows a single MVC track,
the mvcC mapping is present, ~144k BlockAdditionals carry the dependent
view (8.7 GB), and the base view decodes cleanly with no regression.
MVCDecoderConfigurationRecord follows ISO/IEC 14496-15 7.6.2; StereoMode
is intentionally omitted (no enum value describes MVC-in-BlockAdditional;
the mvcC mapping is the primary 3D signal per RFC 9559).
Round-11 findings from the 10-phase release audit (no real HIGH):
- When a no-declared-duration source (HD-DVD) muxes a degenerate single
frame at tick 0 with no per-frame duration, max_block_ticks stays 0 and
the reserved DURATION placeholder was left as a literal 0.0 (players read
that as a zero-length file). Void the element instead, so the Segment
omits DURATION as an unknown-duration source did before the back-patch.
- Add a regression test for the sniff_video_codec overlap fix (a
picture_start_code whose payload begins 00 00 followed by a real start
code) so the i+=4 marker skip can't silently regress to i+=3.
Round-4 findings from the 10-phase release audit (the first fully clean
round; it dug into the new #22/#18 refactor code):
- AuAssembler closed each AU from only the FRONT mark's fields, so when
one PES fragment carried the source and a later fragment of the same AU
carried the PTS, the second field was dropped — a regression vs the old
separate pts/source mark deques. Now merge the first Some of each field
across all in-range marks.
- parse_vti_clip_order picked the largest residue bucket with
HashMap::into_values().max_by_key(), nondeterministic on a size tie
(randomized HashMap iteration) — could select a different clip table
run-to-run. Break ties by smallest offset.
- Bound the marks/disc_marks deques (MAX_MARKS): the buf-size cap prunes
marks only when bytes accumulate, so a run of zero-length timed
fragments could grow them without bound on hostile input.
- Add push_owned so the PS path moves the PES payload into a passthrough
AU with no copy (MPEG-2 video + all audio), removing a per-PES
malloc+memcpy the refactor had introduced on the DVD path.
- Back-patch the MKV duration from the block END (start + its own
duration) so it covers the final frame instead of understating by one.
- Add direct tests for the MKB record-framing walker; drop a stale
drain_complete_aus doc comment left on process_au.
A title whose scan yields no duration (HD-DVD — its `.MAP` timemaps are
not parsed, so DiscTitle.duration_secs is 0) produced an MKV with no
Segment Duration element, so players/MediaInfo reported an unknown
runtime.
Reserve a DURATION placeholder when the source declares none, track the
highest block timestamp written, and back-patch the placeholder at
finish() with the real muxed runtime (also enabling the per-track BPS
tags for these titles). Gated on duration_secs == 0, so BD/UHD/DVD —
which carry a real mpls/IFO duration — write it up-front exactly as
before, unchanged.
Pairs with A2 (read-path NULL-TS concealment). When the demux assembler
sees a TS continuity gap it now stamps `discontinuity` on the next
completed PES; the codec-parse stage carries that onto a per-track
ResyncGate. After a gap on an inter-coded video track the gate drops
forward to the next IRAP/IDR keyframe so no frame with a dangling
reference reaches the muxer (an ffmpeg deep scan would otherwise report
a missing-reference / non-existing-PPS error). Audio and subtitle tracks
have no cross-frame references, so the gate is a no-op there.
- ts.rs: PesPacket gains `discontinuity`; PesAssembler tracks a sticky
pending_discontinuity flag set on CC gap / discontinuity_indicator and
carried to the next completed/flushed PES.
- resync.rs (new): ResyncGate — per-track arm-on-gap, drop non-keyframes
until the next keyframe disarms and resumes. Logs the resync + drop
count once at the keyframe.
- pipelined_stream.rs: precompute per-track is_video, apply the gate in
consume_ts. Out-of-range track index emits as-is (defensive).
Tests: ResyncGate unit tests; ts.rs gap-stamps-discontinuity; end-to-end
B1 video-drops-to-keyframe and audio-never-drops through PipelinedPesStream.
The CLI --version, the MKV muxing/writing-application field, and the FVI generator
all derive from one libfreemkv const, so a binary reports the exact same label it
stamps into the files it produces — no split-brain where an MKV claims one version
and the binary another.
build.rs emits FREEMKV_VERSION = FREEMKV_BUILD_LABEL when that env is set
(non-empty), else the Cargo package version. The muxing/writing-application
field and the FVI generator tag use it, so a pre-release/test build can be
stamped without bumping Cargo.toml and disturbing the tag-pinned [patch]
version matching. The git short hash is still appended either way.
TrueHD: when the PES PTS lags the access-unit cadence, resync to the PTS
but never snap the running timestamp backward, so the emitted DTS stays
monotonic across the resync (next_pts_ns = max(next_pts_ns, pts)).
DTS-HD MA: size each EXSS extension substream exactly from its header
(exss_frame_size) and skip it as a unit, so a false 0x7FFE8001 core sync
inside the lossless extension payload can no longer split the access unit
and truncate the extension. Falls back to a bounded scan when the header
is unparseable.
Provenance: build.rs bakes the git short hash into GIT_SUFFIX; the muxing/
writing-application field and the FVI generator tag now record the exact
build (e.g. "freemkv 1.1.0-beta.1 (g835cc99)"), so any output file is
traceable to the revision that produced it.
Surgical fixes (each with a regression test that fails without the change):
mux/mkv.rs, mux/demux_sink.rs: drive the clip-boundary timeline epoch
off the resolved PRIMARY VIDEO track, not the literal stream index 0.
An M2TS/PMT title can list an audio ES before video, so streams[0] may
be audio; a non-video epoch driver ratchets the frontier and inflates
the timeline. mkv cluster-opening falls back to track 0 for audio-only
titles so they still open clusters.
mux/codec/ac3.rs: correct ACMOD_CHANNELS — acmod=5 (3/1) is 4 channels,
not 3 (was undercounting a 3/1 stream); fix the A/52 Table 5.8 doc.
disc/mod.rs: HDMV coding_type 0x91 (Interactive Graphics / menus) no
longer maps to PGS subtitle — it falls through to Unknown so the PMT/STN
walker drops it instead of surfacing a bogus subtitle track.
mux/videomap.rs + mux/mkv.rs: FVI colour now mirrors the MKV muxer's CICP
precedence (measured CICP authoritative; HDR-driven PQ/HLG transfer
override) via a shared cicp_for_video helper, so the two sinks can't
disagree (HDR10 BT.2020 no longer emits SDR transfer 14).
mux/mkvstream.rs: saturating_add on cluster_ts + rel_ts so an adversarial
CLUSTER_TIMESTAMP near i64::MAX can't overflow/panic before the existing
saturating_mul.
mux/timeline.rs: tighten the tail-straggler clamp so a normal new-epoch
non-video frame leading the sparse video frontier by >3s is not demoted
into the previous clip's epoch.
mux/m2ts_mux/mod.rs: re-stamp PCR per video TS packet (mid-PES), not only
at PES boundaries, so a large UHD I-frame can't open a multi-second PCR
gap; modular 33-bit PTS rebasing so a real 90 kHz clock wrap is not
collapsed to PTS 0 (pre-base frames still floor to 0).
io/byte_prefetcher.rs, sector/prefetched.rs: wrap the producer feed loop
in catch_unwind and emit a typed error sentinel on panic, so a mid-stream
producer panic is not read as a clean EOF at the demux boundary (which
would silently truncate the mux).
mux/codec/h264.rs: extend HIGH_PROFILES to the full ISO/IEC 14496-15 set
that mandates the avcC chroma/bit-depth extension (adds 244 et al.).
Doc/comment accuracy: css/mod.rs (50000 sectors, not scrambled-sectors),
aacs/decrypt.rs (decrypt_unit already-clear path), ifo.rs (TT_SRPT at
0xC4), css/lfsr.rs (LFSR0 24-bit; TAB1-then-XOR cipher; real scramble-flag
predicate), disc/read_error.rs (for_sweep does bounded transient retries).
Skipped: keydb.rs SSRF guard (low/latent, no live caller) — a hard
loopback block breaks an existing behavioral test that exercises the
header-EOF path over a loopback server; a clean fix needs a resolver test
seam beyond this surgical pass. The sibling keydb_fetch.rs comment fix is
out of scope (freemkv crate).
Parse the two HDR10 HEVC SEI messages and emit the corresponding
Matroska Colour metadata, only when actually present in the bitstream
(SDR / no-SEI tracks omit it; nothing is fabricated).
Parse (Rec. ITU-T H.265 Annex D):
- Mastering Display Colour Volume SEI, payloadType 137 (D.2.28):
display_primaries_x/y[3] (SEI order G,B,R), white_point_x/y
(0.00002 units), max/min_display_mastering_luminance (0.0001 cd/m²).
- Content Light Level Info SEI, payloadType 144 (D.2.35):
MaxCLL / MaxFALL (cd/m² integers).
HevcParser::scan_sei walks the sei_rbsp ff-extension payloadType/
payloadSize coding and de-emulates (00 00 03) before reading, reusing
the existing strip_emulation_prevention helper. Both SEI are required
before any metadata is surfaced; SEI NALs still pass through unchanged.
Carry: the measured Hdr10Metadata rides PictureInfo (the same per-coded-
picture seam FieldOrder uses), flowing through from_codec_frame onto
PesFrame.coding to the deferred-muxer activate path, where
apply_coding_to_track stamps it on the video track before the header is
written. Set only when both SEI were seen.
Emit (RFC 9559 / Matroska): new Colour children in ebml.rs
(MasteringMetadata 0x55D0, Primary R/G/B + WhitePoint chromaticity
0x55D1..0x55D8, Luminance max/min 0x55D9/0x55DA, MaxCLL 0x55BC,
MaxFALL 0x55BD). write_hdr10 converts chromaticity SEI int × 0.00002 →
Matroska float, luminance SEI int × 0.0001 → cd/m² float; MaxCLL/MaxFALL
are uints verbatim. SEI primary index 0/1/2 (G/B/R) mapped to the
Matroska R/G/B element layout. Emitted only when hdr10 is present.
Tests: SEI parse with exact raw values, requires-both-SEI, SDR omission,
and emulation-prevention stripping (hevc.rs); muxer emit with exact unit
scaling + SDR omission of MasteringMetadata/MaxCLL/MaxFALL (mkv.rs);
apply_coding_to_track HDR10 plumbing (mkvstream.rs).
mux/mkv: assert emitted CODEC_PRIVATE bytes verbatim for H.264/HEVC/VC-1/
MPEG-2 (direct TrackEntry child, not nested in Video) and DefaultDuration ns
for all eight frame rates, read back out of a real MkvMuxer.
disc/sweep: end-to-end Disc::sweep against a synthetic MockReader with an
injected bad region, asserting the resulting mapfile marks the clean lead
Finished and the failed batch + zero-filled skip-ahead gap NonTrimmed,
proving the Pass-1 damage-jump engaged.
disc/patch: introduce a minimal clock seam (fn() -> Instant on the internal
PatchLoopState, defaulting to Instant::now) so the per-range and whole-pass
watchdogs are deterministically testable; public API and callers unchanged,
production behavior identical. Add tests that advance a fake clock to trip the
range budget and whole-pass stall predicate.
aacs: add an AES-128-CBC known-answer test for aes_cbc_decrypt using the
published NIST SP 800-38A F.2.2 vector (blocks 1..3 exact; block 0 via the
documented fixed-AACS-IV substitution).
Carry per-picture truth and byte-exact source provenance THROUGH the stream so
the muxer (and the upcoming video index) read MEASURED facts instead of
assuming them. Honest data in, honest data out.
- codec/coding.rs: codec-agnostic PictureInfo (CodingType / FieldOrder + the
accessors field_order/coding_type/nb_fields/progressive/keyframe). Each codec
folds its raw signals in; consumers use only accessors, never branch on codec.
- mpeg2: builds PictureInfo from the picture coding extension and carries it +
SourcePos (source_marks, parallel to pts_marks) on every emitted frame.
- pes / codec::Frame: additive `coding` + `source`, forwarded through the
highway; None for audio/subtitle and the network/stdio deserialize hop.
- mkvstream: DEFER muxer construction until the first coded picture, set the
video track's FieldOrder from the MEASURED value, THEN write the header —
right the first time, no guess, no seek-back. An interlaced track that arrives
with no measured order is LOGGED loudly and left UNDETERMINED, never faked.
- mkv: MkvTrack::video no longer guesses TFF (a bitstream property the scan
cannot know is UNDETERMINED at build). Removed VideoStream::top_field_first
(the dead scan-time guess) crate-wide.
- Tests: parser population (every PictureInfo facet + per-PES source carry) and
mux-stream consumption (measured -> correct; missing -> UNDETERMINED, not
faked). Two obsolete tests updated only after confirming (their own comments)
they existed to enforce the deleted hardcoded-TFF.
- FieldOrder now derives from the bitstream's measured top_field_first
(Some(true)→TFF, Some(false)→BFF) instead of hardcoding TFF for all
interlaced content; falls back to TFF when unmeasured. Adds
VideoStream::top_field_first; DVD/BD scan sets None with a precise
TODO(spec) for parser→title plumbing.
- CICP (matrix/transfer/primaries/range) now prefers measured CICP from
the bitstream (VideoStream::measured_cicp) over the coarse ColorSpace
enum, so the container stops assuming a colour space the stream may
contradict. Enum remains the fallback.
- VobSub S_VOBSUB CodecPrivate now emits a `size: WxH` line ahead of the
palette per the .idx format so players place/scale subs correctly.
- SeekHead: when zero cues are written, the CUES Seek entry is Voided
instead of leaving a dangling pointer to the Cues offset (now Tags/EOF).
- AC-3 Channels back-patch offset is captured from the writer instead of
the hardcoded chan_elem_pos+2 (decoupled from the VINT width choice).
- Hoisted inline CICP codes and the dvcC fourcc to named constants citing
ITU-T H.273 / RFC 9559; fixed the stale FieldOrder comment.
- DefaultDuration vs pulldown: precise TODO(spec) left (needs the same
parser→title channel as top_field_first).
Tests: BFF-from-measured-flag, measured-CICP-overrides-enum, VobSub size:
line present/omitted, zero-cue SeekHead Void. precommit (1.86) green.
Delete re-implementations in the demux:// sink and wire to proven helpers;
keep only genuinely-new functionality.
- AnnexB reframing: delete the sink's local length_prefixed_to_annexb (it
break'd on a zero-length NAL, dropping the rest of the access unit) and
call the canonical append_length_prefixed_as_annex_b in mux::hevc, which
skips just the empty NAL.
- HEVC param sets: delete hvcc_param_sets; reuse hvcc_to_annex_b.
- avcC param sets: hoist as the new canonical avcc_to_annex_b in mux::hevc,
next to hvcc_to_annex_b (the symmetry point); the sink calls it.
- PGS .sup: emit a synthetic clear display set (empty PCS + END) at
pts + duration_ns so subtitles time out instead of lingering to EOF.
- TimelineContinuity: move verbatim into the shared mux::timeline module
(with the prev_offset straggler-remap intact) and use it from both the
MKV muxer and the demux sink; delete the sink's drifted TimelineRebase
copy (which lacked the straggler branch).
- VobSub .idx: emit the conventional 'id: <lang2>, index: 0' line mkvmerge
reads to assign the subtitle language; palette reuse unchanged.
- output(): seed DemuxOptions.base from title.playlist when non-empty.
New constants for the PGS clear-segment framing and avcC header cite the
public HDMV PGS (BD-ROM Part 3) and ISO/IEC 14496-15 specs.
Tests: a zero-length NAL mid-frame no longer truncates the AU; a frame with
duration_ns produces a .sup clear segment; existing demux tests stay green.
The existing cue tests (cue_count_equals_cluster_count,
cue_positions_resolve_to_clusters, cue_times_match_cluster_timestamps)
all feed frames with duration_ns=None, so they exercise only the
SimpleBlock write path (UHD/HEVC). DVD MPEG-2 video is now VFR: every
coded picture carries a per-frame duration_ns=Some(..), so it is written
as a BlockGroup, not a SimpleBlock. That cue path was untested.
Add cue_count_equals_cluster_count_blockgroup_vfr, which drives the real
Mpeg2Parser end-to-end (decode-order frames, non-monotonic B-frame
display PTS, telecine field durations) into the muxer and asserts the
output is wholly BlockGroup (no SimpleBlock) and that the Cues index has
exactly one cue per cluster, with every cue resolving to a real cluster.
Guards the DVD seek index (scrub/fast-forward) against regressing to the
chapter-seek-only, zero-cue state.
Matthew Jackson