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AI Slop Code RIsk Monitor

libjxl/libjxl

JPEG XL image format reference implementation

7.1 Moderate pattern signal View on GitHub

Maintenance and Governance Review

This report summarizes scanner evidence for libjxl/libjxl, a C++ project with 3,703 GitHub stars. SynthScan examined 56,188 lines of code across 463 source files, recording 374 pattern matches distributed across 10 syntactic categories. The legacy adjusted pattern signal is 7.1 (Moderate pattern signal); it is not an authorship estimate.

Use the findings to ask whether maintainers can explain intent, verify dependencies, simplify unnecessary scaffolding, and focus review effort. Risk Payload v1 adds ownership, supply-chain, over-engineering, and review-effort vectors when available. These are prompts for human verification, not probabilities, security findings, or measured maintenance costs.

7.1
Adjusted Signal
7.1
Raw Pattern Score
100%
Time Factor
2026-10-11
Last Push
3.7K
Stars
C++
Language
56.2K
Lines of Code
463
Files
374
Pattern Hits
2026-10-12
Scan Date
0.00
HC Hit Rate

Risk Review · v3

Use each vector to guide manual verification of the underlying findings.

Cognitive Ownership Risk 28.9/100 · MEDIUM

Can maintainers explain intent, assumptions, and trade-offs? 361 finding(s).

Hallucinated Dependency & Supply Chain Risk 0.9/100 · LOW

Are imports declared and package/API names verified? 10 finding(s).

Agent Over-Engineering Ratio 0.8/100 · LOW

Are wrappers, guards, and repeated structures necessary? 4 finding(s).

PR Review Velocity Impact 28.9/100 · MEDIUM

Which changes need focused human review? 374 finding(s).

What These Metrics Mean

Adjusted Signal
Legacy pattern score normalized per 1,000 scanned lines and multiplied by the repository-level time factor. It is not an estimate of AI authorship.
Raw Pattern Score
Sum of severity- and context-weighted pattern findings before applying the time factor.
Time Factor
A coarse multiplier based on repository last-push metadata. It does not identify when individual code was written.
Pattern Hits
Count of configured pattern findings. Review each location and surrounding code before acting.
HC Hit Rate
High- and critical-severity findings per scanned file. Severity is a configured detector weight, not proof of a vulnerability or authorship.
Lines / Files
Scan coverage denominators used by the legacy normalized score.

Pattern-Signal History

Run additional scans to build a history of the legacy pattern signal. Score changes are not a measure of AI adoption or code quality.

No multi-scan history yet — run the scanner again to build trend data.

Severity Breakdown

Groups findings by configured severity weight. Severity is not a confidence estimate, security rating, or proof that a package is missing. Verify imports against the project's manifests and inspect each finding in its local design context.

CRITICAL 0HIGH 1MEDIUM 2LOW 371

Directory Score Breakdown

This horizontal bar chart shows where configured pattern scores accumulate across directories. Treat the bars as locations to inspect, not as evidence of authorship or code quality. Use the file-level findings to decide whether a directory needs a focused ownership, dependency, complexity, or review check.

Pattern Findings

The scanner identified 374 distinct pattern matches across 10 syntactic categories. Each entry below represents a discrete location in the source code where the engine recorded a detector match to inspect in context. Expand any category row to inspect the individual file paths, line numbers, code snippets, and the lexical context (CODE, COMMENT, or STRING) in which each match was detected.

Reading the findings table: The Severity column indicates the configured finding weight (CRITICAL / HIGH / MEDIUM / LOW). The Context column identifies whether the match occurred inside executable code, an inline comment, or a string literal — legacy comment-context matches receive a ×1.5 score weight. The ⚡ bolt icon marks clustered matches: three or more patterns within a 10-line window, each receiving an additional ×1.5 density multiplier under the legacy scoring model.

Over-Commented Block331 hits · 331 pts
SeverityFileLineSnippetContext
LOWCMakeLists.txt281endif()COMMENT
LOWCMakeLists.txt301 # to pass -lstdc++ explicitly before -lpthread. For pure C programs -lstdc++COMMENT
LOWci.sh221COMMENT
LOWtools/tracking_memory_manager.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/file_io.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/cmdline.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/ssimulacra.txt81COMMENT
LOWtools/args.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/codec_config.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/gauss_blur.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/thread_pool_internal.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/benchmark/benchmark_codec.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/benchmark/benchmark_codec_custom.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/benchmark/benchmark_codec_custom.h21//COMMENT
LOWtools/benchmark/benchmark_stats.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/benchmark/benchmark_codec_jxl.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/benchmark/benchmark_file_io.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/benchmark/benchmark_codec_webp.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/benchmark/benchmark_args.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/hdr/image_utils.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/hdr/image_utils.h21#include "lib/extras/dec/decode.h" // Codec enumCOMMENT
LOWtools/comparison_viewer/codec_comparison_window.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/comparison_viewer/image_loading.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/comparison_viewer/split_image_renderer.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/flicker_test/split_view.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/flicker_test/test_window.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWtools/jni/org/jpeg/jpegxl/wrapper/decoder_jni.h41#endifCOMMENT
LOWplugins/gdk-pixbuf/pixbufloader-jxl.c1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWplugins/mime/CMakeLists.txt1# Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWthird_party/CMakeLists.txt1# Copyright (c) the JPEG XL ProjectCOMMENT
LOWthird_party/dirent.h1// Copyright (c) the JPEG XL ProjectCOMMENT
LOW.github/workflows/codeql.yml1# Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOW.github/workflows/dependency-review.yml1# Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOW.github/workflows/release.yaml1# Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOW.github/workflows/scorecard.yml1# Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/testing.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/testing.h21#if JPEGXL_ENABLE_TRANSCODE_JPEGCOMMENT
LOWlib/jxl/testing.h41// googletest before 1.10 didn't define INSTANTIATE_TEST_SUITE_P() but insteadCOMMENT
LOWlib/jxl/convolve-inl.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_patch_dictionary.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_ans_params.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_photon_noise.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_comparator.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_comparator.h21COMMENT
LOWlib/jxl/enc_entropy_coder.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_dot_dictionary.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/noise.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_modular_simd.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/dec_patch_dictionary.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/dec_patch_dictionary.h41 // The new values (in the crop) get multiplied by the old ones:COMMENT
LOWlib/jxl/dec_external_image.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/dec_external_image.h41 jxl::Orientation undo_orientation);COMMENT
LOWlib/jxl/dec_transforms-inl.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_frame.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_frame.h21#include "lib/jxl/enc_cache.h"COMMENT
LOWlib/jxl/enc_frame.h41 // colorspace (as deduced by cparams).COMMENT
LOWlib/jxl/enc_splines.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_lz77.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_modular.h1// Copyright (c) the JPEG XL Project Authors. All rights reserved.COMMENT
LOWlib/jxl/enc_modular.h21#include "lib/jxl/dec_modular.h"COMMENT
271 more matches not shown…
Verbosity Indicators7 hits · 15 pts
SeverityFileLineSnippetContext
LOWlib/jxl/modular/transform/palette.h49// The purpose of this function is solely to extend the interpretation ofCOMMENT
LOW⚡lib/jxl/base/fast_math-inl.h98 // Step 1: range reduction to [0, 2pi)COMMENT
LOW⚡lib/jxl/base/fast_math-inl.h103 // Step 2: range reduction to [0, pi]COMMENT
LOW⚡lib/jxl/base/fast_math-inl.h105 // Step 3: range reduction to [0, pi/2]COMMENT
LOW⚡lib/jxl/base/fast_math-inl.h108 // Step 4: Taylor-like approximation, scaled by 2**0.75 to make angleCOMMENT
LOW⚡lib/jxl/base/fast_math-inl.h116 // Step 5: angle duplication.COMMENT
LOW⚡lib/jxl/base/fast_math-inl.h120 // Step 6: change sign if needed.COMMENT
Structural Annotation Overuse6 hits · 14 pts
SeverityFileLineSnippetContext
LOW⚡lib/jxl/base/fast_math-inl.h98 // Step 1: range reduction to [0, 2pi)COMMENT
LOW⚡lib/jxl/base/fast_math-inl.h103 // Step 2: range reduction to [0, pi]COMMENT
LOW⚡lib/jxl/base/fast_math-inl.h105 // Step 3: range reduction to [0, pi/2]COMMENT
LOW⚡lib/jxl/base/fast_math-inl.h108 // Step 4: Taylor-like approximation, scaled by 2**0.75 to make angleCOMMENT
LOW⚡lib/jxl/base/fast_math-inl.h116 // Step 5: angle duplication.COMMENT
LOW⚡lib/jxl/base/fast_math-inl.h120 // Step 6: change sign if needed.COMMENT
Deep Nesting10 hits · 10 pts
SeverityFileLineSnippetContext
LOWtools/benchmark/metrics/plots.py57CODE
LOW…caling_coefficients/generate_upscaling_coefficients.py169CODE
LOWtools/optimizer/apply_simplex.py52CODE
LOWtools/scripts/check_author.py17CODE
LOWtools/scripts/demo_progressive_saliency_encoding.py53CODE
LOWtools/scripts/demo_progressive_saliency_encoding.py77CODE
LOWtools/scripts/build_stats.py291CODE
LOWtools/conformance/generator.py21CODE
LOWtools/conformance/conformance.py84CODE
LOWtools/conformance/conformance.py229CODE
Unused Imports10 hits · 10 pts
SeverityFileLineSnippetContext
LOWtools/benchmark/metrics/iqa.py18CODE
LOWtools/optimizer/simplex_fork.py19CODE
LOWtools/optimizer/simplex_fork.py20CODE
LOWtools/optimizer/simplex_fork.py21CODE
LOWtools/optimizer/simplex_fork.py23CODE
LOWtools/optimizer/simplex_fork.py26CODE
LOWtools/scripts/demo_progressive_saliency_encoding.py29CODE
LOWtools/scripts/demo_progressive_saliency_encoding.py30CODE
LOWtools/scripts/demo_progressive_saliency_encoding.py31CODE
LOWtools/conformance/generator.py18CODE
Slop Phrases5 hits · 10 pts
SeverityFileLineSnippetContext
LOW⚡lib/jxl/cms/color_encoding_cms.h54 // NB: don't forget to update EnumBits!COMMENT
LOW⚡lib/jxl/cms/color_encoding_cms.h63 // NB: don't forget to update EnumBits!COMMENT
LOW⚡lib/jxl/cms/color_encoding_cms.h72 // NB: don't forget to update EnumBits!COMMENT
LOWlib/jxl/cms/color_encoding_cms.h84 // NB: don't forget to update EnumBits!COMMENT
LOWlib/jxl/cms/color_encoding_cms.h93 // NB: don't forget to update EnumBits!COMMENT
Empty Error Handlers1 hit · 5 pts
SeverityFileLineSnippetContext
HIGHtools/scripts/demo_progressive_saliency_encoding.py160except OSError:CODE
Excessive Try-Catch Wrapping2 hits · 3 pts
SeverityFileLineSnippetContext
LOWtools/scripts/demo_progressive_saliency_encoding.py68 except Exception as exn:CODE
MEDIUMtools/scripts/build_stats.py410 print('Error: %s exceeds stack limit: %d vs %d' % (CODE
Self-Referential Comments1 hit · 3 pts
SeverityFileLineSnippetContext
MEDIUMtools/conformance/generator.py89 # Create the test descriptor file.COMMENT
AI Structural Patterns1 hit · 1 pts
SeverityFileLineSnippetContext
LOWtools/conformance/lcms2.py59CODE