Add JPEG 2000 codestream-level validation for IMF App2E - #1
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Adds optional codestream-level validation (SMPTE ST 2067-21) that parses the JPEG 2000 codestream main header of sampled frames and checks profile conformance, codestream-vs-descriptor consistency, and marker presence. - JPEG2000Codestream: main-header parser (SOC/SIZ/CAP/COD/QCD) into the existing J2KHeaderParameters model, plus J2KHeaderParameters.fromCodestream. - IMFTrackFileReader: getEssenceElementHeaderBytes (CBE/VBE index resolution + KLV walk to first essence element); getPictureEssenceCodingUL and getDescriptorJ2KHeaderParameters; IndexTableSegment getters; GenericPictureEssenceDescriptorBO.getPictureEssenceCodingUL. - EssenceSamplingPolicy (none|first|every:N|all, default none), J2KProfileConstraints (IMF/Broadcast checkers), and J2KCodestreamValidator (dispatch by picture essence coding UL; reuses validateHTConstraints for HT). Findings are NON_FATAL. - Wired into IMPAnalyzer.analyzeDelivery and analyzeFile via the --j2k-codestream CLI flag (existing overloads preserved). - Constraint reference doc, README usage, and unit/integration tests. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Two issues surfaced by running first-frame validation on real IMF J2K track files: - J2KHeaderParameters.fromJPEG2000PictureSubDescriptorBO dereferenced the JPEG 2000 extended capabilities (CAP) unconditionally, throwing an NPE for non-HT IMF/Broadcast essence that carries no CAP marker. Now null-guarded, matching the fromDOMNode convention (CAP left null when absent). - Essence frame extraction did not filter body partitions by BodySID, so for files that multiplex multiple essence containers (e.g. a picture track interleaved with a data/XML track) it could read the wrong container. The extractor now carries the target BodySID from the resolving index table and selects only matching body partitions. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Walks the JPEG 2000 tile-part structure to verify the TLM marker, which is required by the App2E profiles and a known field-conformance issue. - JPEG2000Codestream now parses TLM marker segment(s) and walks the tile-part chain: it navigates SOT->SOT by Psot, verifies each jump lands on an SOT/EOC, measures each tile-part length, and detects the terminating EOC. Exposes getTLMEntries()/getTileParts()/isTilePartStructureValid()/reachedEndOfCodestream(). - IMFTrackFileReader.getEssenceElementBytes reads the whole essence element (shared offset resolution with getEssenceElementHeaderBytes). - J2KCodestreamValidator reads the full frame and checks TLM presence, tile-part structural consistency, EOC termination, and that the declared TLM lengths match the measured tile-part lengths (count, per-entry length, tile index). - Unit tests for tile-part walking and conformant/non-conformant TLM; validator test narrowed to consistency + structural invariants. Verified against real material: the IMF picture track passes TLM conformance. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Adds optional codestream-level validation (SMPTE ST 2067-21) that parses the JPEG 2000 codestream main header of sampled frames and checks profile conformance, codestream-vs-descriptor consistency, and marker presence.