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vangel76
39afd2f6c3
Problem: symphonia rejects every Layer II frame whose bit rate / mode combination ISO/IEC 11172-3 does not allow (mono above 192 kbit/s, stereo below 64 kbit/s). ffmpeg writes mono MP2 at 384 kbit/s by default, so such tracks played as silence in MPEG-TS / PS, Matroska and raw .mp2 files. Fix: new L0 crate filmcraft-mpa, a clean-room Layer I / II decoder written from ISO/IEC 11172-3 and 13818-3 (all modes incl. joint stereo, MPEG-1/2/2.5 rates, the disallowed combinations decoded with the allocation table their bit rate per channel selects). PacketDecoder::mpeg_audio uses it for layers I and II (packets of several frames too); raw .mp2 files decode with it, resyncing after damage. Oracle tests vs ffmpeg: 73-84 dB SNR on ffmpeg / twolame streams and synthetic Layer I / joint stereo frames; fuzzed damaged frames never panic. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
18 lines
400 B
TOML
18 lines
400 B
TOML
[package]
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name = "filmcraft-mpa"
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description = "Clean-room MPEG-1/2 Audio Layer I and Layer II (MP1 / MP2) decoder"
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version.workspace = true
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edition.workspace = true
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license.workspace = true
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rust-version.workspace = true
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[lints]
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workspace = true
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[dependencies]
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filmcraft-bitstream = { workspace = true }
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thiserror = { workspace = true }
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[dev-dependencies]
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filmcraft-testkit = { workspace = true }
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