Close AV1 OBU framing verification

HEIF_IMPLEMENTATION_PLAN.md

@@ -29,7 +29,7 @@ Checkboxes may be marked complete only when the implementation and the verificat
 
 ## Delivery dashboard
 
-Last reconciled with the source tree on 2026-08-29 against production checkpoint `15613b01c0bc098fd9926b886216558e0d26eff9`. Committed checkpoints include the AV1 transform architecture, OBU framing, intra-block copy, official extreme-displacement intra-block-copy conformance, the 12-profile reconstruction matrix, corrected twelve-bit inverse-transform SIMD arithmetic, layered-item properties, layered reference/header/CDF/motion-field state, inter-frame intra blocks, SIMD-first translational prediction, complete single-reference inter reconstruction, compound reference trees and modes, paired reference-MV derivation, reference-dependent bounded sequence decoding, allocation-free SIMD-first equal averaging, selected inter-intra prediction, selectable compound blending, OBMC, scaled-reference reconstruction, local warped prediction, non-translational global prediction, official motion-vector conformance, official spatial- and temporal-layer default-operating-point conformance, official active-film-grain sequence conformance, selected spatial-layer presentation, and progressive color and auxiliary-alpha conformance. This dashboard is the authoritative delivery order. The detailed phase checklists below provide subsystem evidence; they do not override the current-stage marker or permit work to skip ahead.
+Last reconciled with the source tree on 2026-08-29 against production checkpoint `da9a46b3d72fd682ea9293af3f88fde26defb222`. Committed checkpoints include the AV1 transform architecture, OBU framing, intra-block copy, official extreme-displacement intra-block-copy conformance, the 12-profile reconstruction matrix, corrected twelve-bit inverse-transform SIMD arithmetic, layered-item properties, layered reference/header/CDF/motion-field state, inter-frame intra blocks, SIMD-first translational prediction, complete single-reference inter reconstruction, compound reference trees and modes, paired reference-MV derivation, reference-dependent bounded sequence decoding, allocation-free SIMD-first equal averaging, selected inter-intra prediction, selectable compound blending, OBMC, scaled-reference reconstruction, local warped prediction, non-translational global prediction, official motion-vector conformance, official spatial- and temporal-layer default-operating-point conformance, official active-film-grain and monochrome sequence conformance, selected spatial-layer presentation, and progressive color and auxiliary-alpha conformance. This dashboard is the authoritative delivery order. The detailed phase checklists below provide subsystem evidence; they do not override the current-stage marker or permit work to skip ahead.
 
 Commit `1c58d855f70b024170ced9eb0a7005f0f9c955ad` records the complete official motion-vector conformance checkpoint. The official IVF has SHA-1 `F064290D7FCD3B3DE19020E8AEC6C43C88D3A505`, matching the pinned libaom test-data manifest, and SHA-256 `222A9050059B254DAB17CFB802FF829C778E3F93AF18961A622C8268576C1395`; its pinned-libaom Y4M has SHA-256 `D97AC78C81782CF1507549368047769DC677DBE205706458D1EE9C807DE6EC78`. Both source targets build with zero warnings and errors, the `net10.0` test-project analyzer build completes with zero errors and 1,014 pre-existing repository warnings, Roslynk reports zero compiler errors, 3,985 focused `net10.0` cases pass without failures or skips, and `git diff --check` is clean.
 
@@ -51,6 +51,8 @@ Commit `03737411e62155df8e998c37475ceeebf4f053bf` records the official two-spati
 
 Commit `15613b01c0bc098fd9926b886216558e0d26eff9` records the official ten-frame active-film-grain checkpoint. The manifest-matching 28,634-byte IVF and pinned-libaom grained Y4M prove every displayed 352x288 YUV420 frame exactly under normal and scalar dispatch; the differing skip-grain digest and explicit coverage prove synthesis is active. The checkpoint corrected the AV1 default loop-filter reference-delta order so Golden is -1 and Backward is 0, restoring exact dependent-frame deblocking before display-only grain. Constrained tracked allocation returns every allocation exactly once. Both Release source targets build with zero warnings and errors, the scoped test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, 28 focused cases pass without failures or skips, and `git diff --check` is clean.
 
+Commit `da9a46b3d72fd682ea9293af3f88fde26defb222` records the official eight-bit monochrome checkpoint. The manifest-matching 10,000-byte IVF and pinned-libaom raw luma reference prove all ten displayed 320x180 YUV400 frames exactly under normal and scalar dispatch. The shared compact-sequence oracle validates native monochrome without manufacturing chroma and keeps every prior YUV420 fixture exact. Constrained tracked allocation returns every allocation exactly once. The existing decoder required no production correction. Both Release source targets build with zero warnings and errors, the scoped test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, all 17 official-sequence cases pass without failures or skips, and `git diff --check` is clean.
+
 Status meanings:
 
 - **Complete:** the implementation and its phase exit evidence are recorded.
@@ -61,7 +63,7 @@ Status meanings:
 
 Current development stage: **Stage 3 — complete AV1 still-image decoding.** The decoder retains reference/header/CDF/motion-field state, derives frame-level skip-mode references, consumes temporal segment prediction, decodes intra-coded blocks inside inter frames, and reconstructs translational single-reference, compound, inter-intra, OBMC, scaled-reference, local warped, and non-translational global prediction before residual traversal. Commit `1c58d855f70b024170ced9eb0a7005f0f9c955ad` adds exact official four-frame coverage through all ordinary inter modes, all three motion modes, every regular/smooth/sharp dual-filter pair, sub-8x8 chroma prediction, and no-round compound intermediates. Commit `019ac5648b4380a6ff4865072c96fde29ce09fad` adds exact selected-layer native reconstruction and scaled presentation. Neither AV1 nor HEVC production encoding is implemented.
 
-Immediate checkpoint: **verification complete; commit pending — official eight-bit monochrome AV1 sequence.** The 10,000-byte official IVF matches the pinned manifest and all ten displayed 320x180 luma planes match pinned libaom exactly under normal and scalar dispatch. The shared compact-sequence oracle now validates native YUV400 without manufacturing chroma planes, while every prior YUV420 caller remains exact. A 2 KiB constrained tracked allocator returns every allocation exactly once. The existing decoder required no production correction. Both Release source targets build with zero warnings and errors, the scoped test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, all 17 official-sequence cases pass without failures or skips, and `git diff --check` is clean. Only the checkpoint commit remains open.
+Immediate checkpoint: **remaining — close tile partitioning, mode information, segmentation, delta quantization, transform-size selection, coefficient decoding, inverse quantization, and inverse transforms.** The complete profile matrix and every partition type are exact, but the parent remains unchecked. Audit the production traversal and its focused tests against pinned libaom, identify the specific valid syntax or evidence gap, and implement only that gap before advancing to intra prediction.
 
 | Order | Delivery stage | State | Delivered state | Gate that remains open |
 | --- | --- | --- | --- | --- |
@@ -571,8 +573,9 @@ Exit gate:
 
 Implement and verify in dependency order:
 
-- [ ] OBU framing, sequence headers, frame headers, tile groups, byte alignment, and trailing bits.
+- [x] OBU framing, sequence headers, frame headers, tile groups, byte alignment, and trailing bits.
   - [x] Isolate every declared OBU payload with a zero-copy bounded span reader, advance ignored metadata and reserved units without parsing their bytes as headers, validate padding and trailing bytes, enforce primary/redundant/combined frame-header order, accept the final unsized low-overhead OBU by consuming the bounded image-item remainder, and reject lengths that cross the containing boundary. Focused malformed-input tests and independent 8/10/12-bit AVIF reconstruction pass in Release.
+  - [x] Re-audit the complete bounded parser against pinned libaom `03087864cf4bea6abb0d28f95cf7843511413d8f`, including ULEB128 and Annex B lengths, operating-point filtering, sequence/frame ordering, redundant-header identity, temporal delimiters, padding, byte alignment, tile-group bounds, tile sizes, and complete ordered tile coverage. AV1-ISOBMFF's final unsized low-overhead OBU remains the deliberate item-specific extension and is covered by a real fixture. Correct the stale direct tile tests to address item-relative tile bytes and make header round-trip diagnostics skip span-valued properties that reflection cannot box. Both Release source builds remain zero-warning and zero-error, the scoped test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, and all 119 focused framing, lifecycle, bit-reader, tiling, and official-sequence cases pass without failures or skips.
 - [x] One coherent bounded decoder lifecycle retains parsed tile state until successful frame completion, commits frame-owned reference samples and metadata only after reconstruction, resets retained state at a new sequence boundary, and disposes tile, reference, entropy, and presentation ownership deterministically. The real two-layer lifecycle fixture proves the header/reference ownership boundary through a fake tile reader; dependent inter reconstruction remains covered by the unchecked items below.
 - [ ] Tile partitioning, mode information, segmentation, delta quantization, transform-size selection, coefficient token decode, inverse quantization, and inverse transforms.
   - [x] Match libaom's depth-first traversal and frame-edge behavior for all ten AV1 partition types. Independent 8/10/12-bit streams collectively select every terminal partition shape and contain nested block geometry that requires recursive `Split` traversal; their complete native planes remain byte-exact under normal hardware dispatch and the scalar fallback.
@@ -615,7 +618,7 @@ Implement and verify in dependency order:
   - [x] Decode the official one-spatial-layer, two-temporal-layer L1T2 sequence at its default operating point. The 48,883-byte IVF has manifest-matching SHA-1 `E94687EB0E90179B3800B6D5E11EB7E9BFB34EEC` and SHA-256 `EADE696AB60415D476E1D2A489EC2CCCD24D5EAAADFA4559C6488B7932274C5E`; its pinned-libaom Y4M has SHA-256 `4012DE2D4AFD095E7BB68EAE18B50B0674781BB4971CECABC0E5471E63373ED3`. All eight 640x360 YUV420 frames match exactly under normal/scalar dispatch, and an 8 KiB constrained tracked allocator verifies balanced exactly-once returns. The existing decoder required no production correction. The scoped test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, and both focused cases pass without failures or skips.
   - [x] Decode the official two-spatial-layer, two-temporal-layer L2T2 sequence at its default operating point. The 119,907-byte IVF has manifest-matching SHA-1 `32EF2F14EE9CB11A24A22934F4C065E926E5D236` and SHA-256 `14257D5FD3901581DBEB88133378CD79D50EA32506ADB729909AB56B4A52AF3C`; its pinned-libaom Y4M has SHA-256 `1ABB981CFF76BA9557DA437B258D8A95FCA755DED8E3949D857E8388AB1D6AE3`. All eight 1280x720 YUV420 frames match exactly under normal/scalar dispatch, and an 8 KiB constrained tracked allocator verifies balanced exactly-once returns. The existing decoder required no production correction. The scoped test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, and both focused cases pass without failures or skips.
   - [x] Decode the official ten-frame active-film-grain sequence. The 28,634-byte IVF has manifest-matching SHA-1 `11BB40026103182C23A88133EDAFCA369E5575E2` and SHA-256 `BA3EDD82A58414F009E1C821B947EC8DE4E0420F33803CA7BFEA39AF6AEEA155`; its pinned-libaom grained Y4M has SHA-256 `C71958DE496A949D12E819190F240BD56010E5AD57D8A0D55903BF380A9E0C26`, while pinned libaom's skip-grain output differs with SHA-256 `9E0762A82E582E854AFF2DC61EBA1E48C0F1D41BBC21E5C896573DA3BB2F1200`. All ten displayed 352x288 YUV420 frames match exactly under normal/scalar dispatch; active synthesis, dependent retained-reference reconstruction, and 2 KiB constrained tracked allocation with exactly-once returns pass. The fixture corrected the AV1 default loop-filter reference deltas from a swapped Golden/Backward pair to the normative `[1, 0, 0, 0, -1, 0, -1, -1]` order. Both Release source targets build with zero warnings and errors, the scoped test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, 28 focused cases pass without failures or skips, documentation review is complete, and `git diff --check` is clean. Commit `15613b01c0bc098fd9926b886216558e0d26eff9` records the checkpoint.
-  - [ ] **Verification complete; commit pending:** decode the official eight-bit monochrome sequence. The 10,000-byte IVF has manifest-matching SHA-1 `A17584012187CD886B64F8CB0F35BFD8D762F9DC` and SHA-256 `3DCC2A3C181F74788BD9575D94F0862D9E914415AC358A4DA4ED7D904F0535B7`; its ten-frame 576,000-byte pinned-libaom luma reference has SHA-256 `6A4F8A68366E801D60A14C00BE6EA88A861B1B631D86DEF8A8DB65EFB6B06FA8`. All ten displayed 320x180 native YUV400 frames match exactly under normal/scalar dispatch, the shared compact-sequence oracle keeps every prior YUV420 fixture exact, and a 2 KiB constrained tracked allocator verifies balanced exactly-once returns. The existing decoder required no production correction. Both Release source targets build with zero warnings and errors, the scoped test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, all 17 official-sequence cases pass without failures or skips, documentation review is complete, and `git diff --check` is clean.
+  - [x] Decode the official eight-bit monochrome sequence. The 10,000-byte IVF has manifest-matching SHA-1 `A17584012187CD886B64F8CB0F35BFD8D762F9DC` and SHA-256 `3DCC2A3C181F74788BD9575D94F0862D9E914415AC358A4DA4ED7D904F0535B7`; its ten-frame 576,000-byte pinned-libaom luma reference has SHA-256 `6A4F8A68366E801D60A14C00BE6EA88A861B1B631D86DEF8A8DB65EFB6B06FA8`. All ten displayed 320x180 native YUV400 frames match exactly under normal/scalar dispatch, the shared compact-sequence oracle keeps every prior YUV420 fixture exact, and a 2 KiB constrained tracked allocator verifies balanced exactly-once returns. The existing decoder required no production correction. Both Release source targets build with zero warnings and errors, the scoped test-project analyzer build completes with zero errors and 1,011 repository warnings, Roslynk reports zero compiler errors, all 17 official-sequence cases pass without failures or skips, documentation review is complete, and `git diff --check` is clean. Commit `da9a46b3d72fd682ea9293af3f88fde26defb222` records the checkpoint.
 - [x] Lossless and high-bit-depth reconstruction with correct clipping and intermediate precision.
   - [x] Route lossless 4x4 blocks through allocation-free reversible inverse Walsh-Hadamard reconstruction for 8/10/12-bit samples, including the DC-only specialization, `Vector128` production traversal, scalar fallback, exact clipping, and `FeatureTestRunner` parity.
   - [x] Verify lossless syntax, inverse quantization, prediction, and presented reconstruction with independently encoded 8/10/12-bit AVIF fixtures. The tests require coded residuals with palette and intra-block copy disabled, compare every native YUV sample with the pinned generic libaom-backed decoder, and compare every presented RGBA byte with pinned generic libavif exactly under normal hardware dispatch and the scalar fallback.

tests/ImageSharp.Tests/Formats/Heif/Av1/Av1TilingTests.cs

@@ -84,7 +84,7 @@ public class Av1TilingTests
         string filePath = Path.Combine(TestEnvironment.InputImagesDirectoryFullPath, filename);
         byte[] content = File.ReadAllBytes(filePath);
         Span<byte> headerSpan = content.AsSpan(dataOffset, dataSize);
-        Span<byte> tileSpan = content.AsSpan(tileOffset, dataSize - tileOffset);
+        Span<byte> tileSpan = content.AsSpan(dataOffset + tileOffset, dataSize - tileOffset);
         Av1BitStreamReader bitStreamReader = new(headerSpan);
         IAv1TileReader stub = new Av1TileDecoderStub();
         ObuReader obuReader = new();
@@ -114,7 +114,7 @@ public class Av1TilingTests
         const int dataSize = 0x001D;
         const int tileOffset = 21;
         Span<byte> headerSpan = content.AsSpan(dataOffset, dataSize);
-        Span<byte> tileSpan = content.AsSpan(tileOffset, dataSize - tileOffset);
+        Span<byte> tileSpan = content.AsSpan(dataOffset + tileOffset, dataSize - tileOffset);
         Av1BitStreamReader bitStreamReader = new(headerSpan);
         IAv1TileReader stub = new Av1TileDecoderStub();
         ObuReader obuReader = new();
@@ -143,7 +143,7 @@ public class Av1TilingTests
         string filePath = Path.Combine(TestEnvironment.InputImagesDirectoryFullPath, filename);
         byte[] content = File.ReadAllBytes(filePath);
         Span<byte> headerSpan = content.AsSpan(dataOffset, dataSize);
-        Span<byte> tileSpan = content.AsSpan(tileOffset, dataSize - tileOffset);
+        Span<byte> tileSpan = content.AsSpan(dataOffset + tileOffset, dataSize - tileOffset);
         Av1BitStreamReader bitStreamReader = new(headerSpan);
         IAv1TileReader stub = new Av1TileDecoderStub();
         ObuReader obuReader = new();
@@ -170,7 +170,7 @@ public class Av1TilingTests
         const int dataSize = 0x03CC;
         const int tileOffset = 18;
         Span<byte> headerSpan = content.AsSpan(dataOffset, dataSize);
-        Span<byte> tileSpan = content.AsSpan(tileOffset, dataSize - tileOffset);
+        Span<byte> tileSpan = content.AsSpan(dataOffset + tileOffset, dataSize - tileOffset);
         Av1BitStreamReader bitStreamReader = new(headerSpan);
         IAv1TileReader stub = new Av1TileDecoderStub();
         ObuReader obuReader = new();
@@ -224,7 +224,7 @@ public class Av1TilingTests
         const int dataSize = 0x03CC;
         const int tileOffset = 18;
         Span<byte> headerSpan = content.AsSpan(dataOffset, dataSize);
-        Span<byte> tileSpan = content.AsSpan(tileOffset, dataSize - tileOffset);
+        Span<byte> tileSpan = content.AsSpan(dataOffset + tileOffset, dataSize - tileOffset);
         Av1BitStreamReader bitStreamReader = new(headerSpan);
         IAv1TileReader stub = new Av1TileDecoderStub();
         ObuReader obuReader = new();
@@ -293,7 +293,7 @@ public class Av1TilingTests
         string filePath = Path.Combine(TestEnvironment.InputImagesDirectoryFullPath, filename);
         byte[] content = File.ReadAllBytes(filePath);
         Span<byte> headerSpan = content.AsSpan(dataOffset, dataSize);
-        Span<byte> tileSpan = content.AsSpan(tileOffset, dataSize - tileOffset);
+        Span<byte> tileSpan = content.AsSpan(dataOffset + tileOffset, dataSize - tileOffset);
         Av1BitStreamReader bitStreamReader = new(headerSpan);
         ObuReader obuReader = new();
         Av1FrameDecoderStub frameDecoder = new();

tests/ImageSharp.Tests/Formats/Heif/Av1/ObuPrettyPrint.cs

@@ -20,14 +20,17 @@ internal class ObuPrettyPrint
         MemberInfo[] properties = obj.GetType().FindMembers(MemberTypes.Property, BindingFlags.Instance | BindingFlags.Public, null, null);
         foreach (MemberInfo member in properties)
         {
-            builder.Append(Spaces, 0, indent);
+            if (member is not PropertyInfo property || property.PropertyType.IsByRefLike)
-            if (member is PropertyInfo property)
             {
-                builder.Append(property.Name);
+                // Reflection cannot box Span<T> or ReadOnlySpan<T>; their owning scalar syntax remains comparable.
-                builder.Append(" = ");
+                continue;
-                object value = property.GetValue(obj) ?? "NULL";
-                PrettyPrintValue(builder, value, indent);
             }
+
+            builder.Append(Spaces, 0, indent);
+            builder.Append(property.Name);
+            builder.Append(" = ");
+            object value = property.GetValue(obj) ?? "NULL";
+            PrettyPrintValue(builder, value, indent);
         }
 
         indent -= 2;