mirror of
https://github.com/storytold/craft-libs.git
synced 2026-11-12 10:03:51 +00:00
anim-frames
1
Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
 Aleksander HelgakerandClaude Opus 5.5
|
ca99f91a18 |
craft-audio: AAC encoder (6/10) (#444)
* craft-audio: AAC decoder
FilmCraft's `filmcraft-aac` decoder as `craft_audio::aac` behind
`aac-decode`, kept over symphonia's: the same quality (about 135 dB
SNR against ffmpeg), and it decodes 5.1, which symphonia refuses.
HE-AAC decodes as its AAC-LC core, upsampled 2x to the stream's rate.
- `TrackDecoder` decodes AAC, including ADTS-framed packets without
extradata (MPEG-TS, raw `.aac`).
- The native read path takes AAC in MP4 and Matroska and raw ADTS
streams (frame sync over the file, with resync after damage).
- AAC errors convert into `AudioError`.
The AAC module's shared parts (Huffman, MDCT, TNS, ICS) arrive whole
as ported; their encoder half is unused until the encoder PR.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 1 (#443)
Raw ADTS and TrackDecoder:
- Channel configuration 0 (a PCE in the stream, as ffmpeg's -aac_pce and
AudioToolbox's 7.x write) decodes; it was refused.
- Frames with several raw data blocks are refused; only their first block
was decoded, silently losing the rest.
- A frame that changes the sample rate, profile or channel configuration is
concealed; it played at the wrong speed.
- A source that fails during the frame scan is AudioError::Io; it looked
like the end of the file.
- A stream after an ID3 tag longer than the file head is found.
- conceal counts all the ADTS frames of a packet, and a packet of more than
1024 frames is refused before it is decoded into memory.
AAC decoder:
- Indexed channel configurations place elements by arrival order, not tag,
as ffmpeg does; tagged differently, channels were swapped.
- A PCE in an access unit that fails no longer changes the layout, which
left every later packet failing.
- Non-finite samples are zeroed before the output and the overlap.
MP4: probe and decode agree: the samples' durations end the track when no
single edit does, and an edit cannot outlast the media.
The routing oracle fails on a fixture ffmpeg cannot write when oracles are
required. The README's Limits names HE-AAC v2 as mono, multi-block ADTS,
iTunSMPB, Matroska's tick precision and AAC in CAF.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 2 (#443)
Corrects round 1:
- A multi-block ADTS frame after the stream has started is concealed at its
whole length; round 1's filter skipped it, shifting the audio after it.
- Sample durations only trim an MP4's last packet: wrong ones (some count a
HE-AAC packet's core frames) were cutting audio. Durations of 0 with an edit
use the edit.
Raw ADTS packets now keep their headers, so TrackDecoder alone handles format
changes, multi-block frames and concealment, for apps as for files, and nested
ADTS payloads are not split again. Headers come from the frame scan's reads,
not one read per frame. The stream's format is the one most of its first frames
share, so one damaged header does not silence the file. The ID3 walk and a
packet's ADTS split are bounded.
AAC:
- HE-AAC is delayed by the SBR filterbanks' 481 core samples; it played 19.5 ms
early against ffmpeg in every container.
- A failed access unit leaves the decoder's state as it was, so the next packet
decodes as if it had not been there.
- reset restarts the noise generator, so a seek into PNS repeats.
- A signalled rate that is not twice the core's plays the core; it reported the
signalled rate with the core's samples.
The decoder oracle's tolerance tightens from 1e-3 to 1e-5. Tests cover HE-AAC.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 3 (#443)
Corrects round 2:
- ADTS headers are compared with the stream's format only when the first header
gave it. With extradata the format comes from there, so ADTS in MP4 whose
headers say something else decodes again; every packet had been concealed.
- A stream's only program config element is found in its first frames even when
that frame's header is damaged.
- The test of wrong sample durations patched the second run's count, not the
delta, so "durations of one" changed nothing. It now patches the delta, and
checks a file was changed and that seeks land on the same audio.
MP4 seeks place a packet by its index when every packet decodes to the same
length, as decoding does; they used the durations round 2 had stopped trusting
for the length, and returned the wrong audio. A last delta of 0 is overridden too.
Docs: what TrackInfo says for raw ADTS, that opening one reads the whole file, and
which codecs symphonia reads.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 4 (#443)
- TrackDecoder takes an ADTS stream's format from the one most of the lookahead
shares, as the file path did, so one damaged first header does not fail every
packet of an MPEG-TS stream. open_adts now just asks it.
- MP4 samples of several ADTS frames keep the sample table's timing; a packet
count of one frame each truncated them silently.
- Sample durations past what the packets decode to no longer over-report the
length.
- split_adts_upto is not behind aac-decode, as split_adts is not: an aac-encode
build in the next PR did not compile.
Removes an unreachable ID_END check and open_adts's unused core rate.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 5 (#443)
No change in decoding. An aac-encode build in the next PR needs the
split_adts_upto re-export behind aac-decode, and ID_END only in tests.
Docs say the lookahead's headers give an ADTS stream's configuration, that AAC in
CAF still goes through symphonia, and that ProgramConfig is not #[non_exhaustive].
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 6 (#443)
Two tests from round 1 failed on ffmpeg before 9, including CI's 8.0. Neither was
a decoding fault:
- ffmpeg 9 ends an MP4 with no edit list at its sample durations and earlier
versions present the whole last packet, so the length is checked against the
file's known duration, not ffmpeg's decode.
- The order ffmpeg gives channels with -aac_pce differs by version, so each decoded
channel must match a different one of ffmpeg's, whatever the order.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 7 (#443)
Reading:
- an element of another type or a tag a program config does not list is
refused, not written to another channel; only an LFE coded as an SCE
is still allowed, as ffmpeg allows it
- an explicit sampling rate of 0 is refused
- a packet's later ADTS frames are searched for SBR
- a multi-frame ADTS packet that fails leaves the decoder as it was, and
one whose frames change the channel count is an error
- the whole ADTS frames before a damaged end of a packet decode
- a failed read of a raw stream's first frames is an I/O error
- an MP4 sample of several ADTS frames past the lookahead keeps its length
- an Ogg file with leading bytes keeps its track order and mask comments
Writing:
- ProgramConfig::write, AudioSpecificConfig::to_bytes and
AdtsHeader::write refuse what their fields cannot hold
Tests:
- the routing test checks one alignment for the ffmpeg version under test
- a default decode past an Ogg stream symphonia has no track for
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 8 (#443)
From wanikhawar's review:
- AudioSpecificConfig::parse reads backward-compatible SBR and PS signalling
(a 0x2b7 sync extension after the config), which craft-media's Matroska
demuxer writes for legacy HE-AAC IDs. Without lookahead those streams decoded
as their core.
- An MP4 media edit after one empty edit is applied: its priming skip and its
end. The empty edit's delay is not added as silence.
- A packet lost whole is concealed as long as the last one decoded, so a stream
of multi-frame ADTS packets keeps its timing.
- ADTS-framed MP4 samples keep their sample table's timing, instead of every
sample being read at open to look for several frames in one.
- AdtsHeader::write refuses an object type, sampling frequency index or channel
configuration its fields cannot hold; it masked them into other values.
- AudioSpecificConfig::lc no longer panics for a sampling frequency index with no
rate, and the decoder refuses such a config.
- AudioSpecificConfig::to_bytes refuses channel configuration 0 without a program
config element, which would not parse back.
- Upsample2x starts each channel's history afresh when the channel count
changes.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 9 (#443)
From CodeRabbit's review of round 8:
- AudioSpecificConfig::parse consumes extensionFlag3 after the config when
extensionFlag is set, so the 0x2b7 sync extension after it is found.
- AudioSpecificConfig::to_bytes refuses a sampling rate of 0, which would not
parse back.
- ADTS-framed HE-AAC in MP4 whose sample durations count core frames is not cut
to the durations' half length: durations short of one frame per sample no
longer end an ADTS-framed track, and its length is unknown until decoded.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 10 (#443)
ADTS-framed AAC in MP4: durations short of the frames in the samples read
ahead no longer end the track. With HE-AAC samples of two ADTS frames each,
timed as two core frames, the durations matched one output frame per sample,
so the undercount check passed and the track stopped at half its length,
which probe reported as known. The frames each read-ahead sample holds are
now counted, and durations short of them leave the length unknown until
decoded, as durations short of one frame per sample already did. Correctly
timed AAC-LC samples of several frames keep their end trim.
Reported by FredApps.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: review fixes, round 11 (#443)
Corrects round 10. A short ADTS-framed MP4 track, whose last sample is in
the read-ahead, lost that sample's trim when it cut more than one frame:
the trim counted as durations falling short, so the length was left to
decoding and its padding was presented. The track's last sample is now left
out of the read-ahead comparison.
Reported by CodeRabbit.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: document the ADTS-in-MP4 seek and edit limits (#443)
AAC in MP4 stored as ADTS frames, with sample durations that count fewer
frames than the samples hold, decodes in full from the start, but seeks
place samples by those durations and land later than asked, and an edit
list measured in them can end the track early. The README's Limits section
now says so, and the seek example points to it.
Reported by FredApps.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* craft-audio: say why the ADTS-in-MP4 seek limit is kept (#443)
The Limits entry from
|