CLAUDE.md

Guidance for Claude Code (and other agents) working in this repository.

Memory: EchoVault (read this first)

This project uses the EchoVault MCP server for persistent, cross-session memory. Prior sessions store architectural decisions, fixed bugs, and gotchas there. Follow this protocol every session:

At session start — load context. Call memory_context (project is auto-detected from cwd) before doing any work. Use memory_search for specific topics (e.g. "detector model", "classic-cv", "false positives").
During work — search before re-deciding. When the task touches an area that may have prior context, memory_search it first instead of re-deriving decisions.
Before ending a session — save what matters. Call memory_save when you made a design decision, fixed a bug (include root cause + fix), found a non-obvious gotcha, or the user corrected/clarified a requirement. Pick the right category (decision / bug / pattern / learning / context). Do not save trivia, things obvious from the code, or duplicates.

EchoVault is the source of truth for why things are the way they are; this file is the stable, high-level map. When they disagree, trust on-disk code first, then EchoVault, then this file — and update whichever is stale.

What this project is

HVideoTool is a Windows-first desktop GUI utility that detects already-applied censorship (mosaic, pixelation, blur, black bars) in images, and draws outlines over the detected censored regions. You open a folder of images; it runs each through a detector, draws the regions, and shows a detailed per-image list of what it found.

Scope was deliberately narrowed (this session). It used to extract frames from video, detect, and play back with overlays (a "project model" with worker threads). That whole video pipeline was removed — the tool is now a simple image-folder inspector for viewing/debugging detector output on test images. Pre-extract video to frames externally if you need that.

Keep this scope sharp:

It is a detection + overlay/inspection tool. It does not remove, restore, or reconstruct censored content.
It does not generate images. There is no ControlNet / SDXL / diffusion pipeline. (xinsir/controlnet-union-sdxl-1.0 was considered early but rejected — a generative model, not a detector. Do not reintroduce it.)
It detects already-censored regions, not "content that should be censored" (i.e. not an NSFW classifier).
It does not decode video. No PyAV. Input is image files only.

Target environment

OS: Windows 11 x64 (primary). Use PowerShell syntax in commands.
Python: 3.11+.
GPU: NVIDIA + CUDA via PyTorch, only for the YOLO detector. CPU fallback works but is slow. The classic detector needs no torch and no GPU.

Tech stack (decided)

Concern	Choice
GUI	PySide6 (Qt 6) — LGPL
Image IO	OpenCV (`opencv-python`) + NumPy, unicode-safe via `core/imageio.py`
Detector	classic-CV heuristic; Ultralytics YOLO (LADA) behind a pluggable interface

Torch/CUDA + Ultralytics enter only with the YOLO detector. Keep that dependency optional (the yolo extra in pyproject.toml pulls only Ultralytics; torch is installed separately per the README). The classic detector must keep running with no torch present.

Architecture (as implemented)

This reflects the actual code on disk. It is a synchronous, single-threaded GUI app — no worker threads, no project/cache files. The only video touch is a one-shot "Создать из ролика…" that decodes a clip to a folder of JPGs via the ffmpeg CLI (cv2.VideoCapture fallback; NOT PyAV); detection still works on image folders only. Detection runs on the GUI thread (lazily per image, or via "Детектировать все"). When code and this file disagree, trust the code.

hvideotool/
├── __main__.py          # entry point + CLI (optional folder arg, --detector, --model)
├── app.py               # QApplication bootstrap; run(config, folder=None)
├── config.py            # AppConfig + DetectionConfig/OverlayConfig (thresholds live here)
├── settings_store.py    # persist detector/model/threshold/last_dir to ~/HVideoTool/settings.json
├── ui/
│   ├── main_window.py   # the whole UI: toolbar + [file list | image view | detail table]
│   └── image_view.py    # renders an image + draws polygon/bbox overlays (QPainter); can highlight one
└── core/
    ├── imageio.py       # unicode-safe imread/imwrite (np.fromfile + imdecode)
    ├── video/
    │   ├── extract.py   # extract_frames(): ffmpeg CLI (cv2 fallback) -> JPGs; keyframe/step modes + downscale
    │   └── frame.py     # Frame dataclass (image BGR, index, pts) — the detector input type
    └── detection/
        ├── base.py      # Detector ABC: detect(frame) -> list[Detection]
        ├── factory.py   # build_detector(config) -> classic | yolo | combined
        ├── types.py     # Detection (+ to_dict/from_dict), CensorType enum
        ├── classic_cv.py  # ClassicCVDetector — heuristic; accepts a `types` filter
        ├── yolo.py      # YoloDetector — Ultralytics YOLO-seg; lazy-imports torch/ultralytics
        └── composite.py # CompositeDetector — merge detectors + IoU dedup

How it works

MainWindow holds the config, builds the detector lazily via build_detector (cached by detector+model+conf in _make_detector), and keeps _results: dict[path -> list[Detection]] as the detection cache.
"Открыть папку" lists image files (_IMAGE_EXTS) with a progress bar (bulk insert with setUpdatesEnabled(False) + periodic processEvents), so a big folder doesn't freeze silently.
Viewing and detecting are decoupled on purpose (so browsing stays instant even with a slow CPU detector): selecting a file only shows it with its cached result (header reads "не рассчитано" if none). Detection runs on double-click, the "Рассчитать кадр" action (Space → _recompute_current, force-recomputes current), or "Детектировать все" (whole folder, progress bar). Do NOT re-add auto-detect-on-select. Results cache in _results; the file-list row gets a count suffix when computed. Switching detector/model clears the cache (_invalidate_results).
Collections (curation). "Создать коллекцию…" makes a destination folder (_collections_base() = the opened folder's parent, else ~/HVideoTool/collections) and marks it active. The file list is ExtendedSelection; "В коллекцию" / Ctrl+M moves (shutil.move, not copy) the selected frames there, removing them from the list/_files/cache. _unique_dest avoids clobbering (foo.jpg → foo (1).jpg). Use case: sort frames into a training/example set while inspecting detections.
image_view.ImageView draws the image scaled-to-fit plus overlays. Overlay visibility/threshold are applied at paint time. Selecting a row in the detail table calls set_highlight(i) — that detection is drawn boldly (even below threshold) and the rest dim. The detail table lists ALL detections (sorted by score), so sub-threshold hits are still visible for debugging; the threshold only affects what's drawn.

Separation of concerns

ui/ must not import torch / ultralytics directly. It builds detectors only via core/detection/factory.build_detector and talks to core/ through the Detector interface and the Detection/CensorType types.
New detector kinds: implement core/detection/base.Detector, register the string in core/detection/factory.build_detector, and add it to _DETECTORS in ui/main_window.py.

Commands

python -m venv .venv; .\.venv\Scripts\Activate.ps1
pip install -e .                       # classic detector needs no torch/CUDA

python -m hvideotool                   # open a folder in-app
python -m hvideotool "C:\path\to\images" --detector yolo --model models\lada_mosaic_detection_model_v4_accurate.pt

pip install -e ".[yolo]"               # + install torch separately, see README

No formal test suite. Headless sanity check: set QT_QPA_PLATFORM=offscreen, build a MainWindow, open_path(folder), drive file_list.setCurrentRow(...), and read detail_table / detail_header. Or run build_detector(config).detect(...) on a frame directly.

Conventions

Match the style of surrounding code; keep core/ free of Qt where reasonable.
Type hints on public functions and the Detector interface.
Model weights (.pt) and large media are not committed — keep them in models/ and .gitignored.
User-facing strings / README are in Russian; code identifiers and this file in English.

Gotchas

Wrong YOLO model = "noise". The YOLO detector needs a censorship model (LADA models\lada_mosaic_detection_model_v4_accurate.pt). If model_path points at a generic COCO model (e.g. the yolo11n-seg.pt in the repo root, which Ultralytics auto-downloads / is the training base), it detects people/objects and maps them to CensorType.UNKNOWN → purple boxes that look like noise. This was a real user trap.
classic-CV is approximate and noisy on real video. Its mosaic heuristic (low block-reconstruction residual + 2D gradient + contrast) fires on textured real footage (skin/hair/fabric/JPEG) → many false positives, while simultaneously missing real mosaic after the proc_max_dim=720 downscale softens block edges (measured: contrast/grad fall below mosaic_contrast_min/mosaic_grad_min). For real-video mosaic use yolo/combined + LADA. For anime there is no good public model.
Domain matters. LADA is trained on REAL video (JAV). It detects some anime mosaic but not all. The real anime fix is retraining a YOLO11-seg (see scripts/training/), not tuning more classic thresholds.
YOLO detector = LADA weights (HF ladaapp/lada). YOLO segmentation model, classes {0: mosaic_nsfw, 1: mosaic_sfw_head} → both map to CensorType.MOSAIC (_name_to_type matches "mosaic" in the class name). Detects mosaic only; black bars / blur stay with classic. Weights + Ultralytics are AGPL-3.0 (accepted). yolo.py lazy-imports torch/ultralytics.
No model weights in the repo. Code must fail with a clear, actionable message when the model path is missing — not a raw stack trace (factory._require_model, YoloDetector.__init__).
CUDA/torch install is environment-specific. Don't add torch to core deps; it stays out (the yolo extra pulls only Ultralytics) and is installed separately.
QImage from a numpy buffer must be .copy()d (see ImageView.set_image), otherwise it aliases a buffer that gets freed → garbage/crash.
Always use core/imageio.py (imread_unicode/imwrite_unicode) for images — cv2.imread/imwrite silently fail on non-ASCII Windows paths.
Don't reintroduce any generative / ControlNet dependency, nor the removed video pipeline (PyAV, project/cache, worker threads, playback). The one allowed video touch is core/video/extract.py (one-shot decode → JPG folder, behind "Создать из ролика…"): ffmpeg CLI — _find_ffmpeg() prefers PATH, else the binary bundled by the imageio-ffmpeg dep, else cv2 fallback. Keyframe-only -skip_frame nokey is ~10× faster than every-frame; -hwaccel does NOT help (GPU transfer overhead). Use ffmpeg/cv2, not PyAV, and keep it synchronous. Decoding every frame is the inherent cost — the speed lever is decoding fewer frames (keyframes).

12 KiB Raw Blame History Unescape Escape