# Caption Quality Test for Cross-View Geo-Localization Validate whether generated text captions improve retrieval R@1 in cross-view geo-localization (drone-to-satellite). ## Architecture ### Overview Asymmetric dual-encoder with domain-specific frozen backbones and hierarchical text fusion for drone-to-satellite image retrieval. ``` ┌──────────────────────────── QUERY BRANCH ────────────────────────────┐ │ │ │ drone_img ──► DINOv3 ViT-L/16 LVD ──► CLS token │ │ [B,3,256,256] (frozen, 303M) d_img [B,1024] │ │ │ │ │ L1 (overview) ──► DGTRS-CLIP ──► z₁ [B,768] ─┐ │ │ L2 (full desc) ──► DGTRS-CLIP ──► z₂ [B,768] ─┼─ cat ──► [B,2304]│ │ L3 (fingerprint) ──► DGTRS-CLIP ──► z₃ [B,768] ─┘ │ │ │ (248 tokens, KPS pos. emb.) MLP(2304→1024→1024) │ │ │ │ │ d_txt [B,1024] │ │ │ │ │ q = σ(α_q)·d_img + (1−σ(α_q))·d_txt GatedFusion_q │ │ │ │ │ q̂ = q / ‖q‖₂ ──► query [B,1024] │ └───────────────────────────────────────────────────────────────────────┘ ┌──────────────────────────── GALLERY BRANCH ──────────────────────────┐ │ │ │ sat_img ──► DINOv3 ViT-L/16 SAT ──► CLS token │ │ [B,3,256,256] (frozen, 303M) s_img [B,1024] │ │ │ │ │ sat_L1 ──► DGTRS-CLIP ──► z₁ [768] ─┐ │ │ sat_L2 ──► DGTRS-CLIP ──► z₂ [768] ─┼─ cat ──► MLP ──► s_txt [1024]│ │ sat_L3 ──► DGTRS-CLIP ──► z₃ [768] ─┘ (shared MLP) │ │ │ │ │ g = σ(α_g)·s_img + (1−σ(α_g))·s_txt GatedFusion_g │ │ │ │ │ ĝ = g / ‖g‖₂ ──► gallery [B,1024]│ └───────────────────────────────────────────────────────────────────────┘ Retrieval space: 1024-dim (DINOv3 native, no projection layers) TextFusionMLP shared between query and gallery branches For sat images without captions: s_txt=None → g = s_img (gate passthrough) BASELINE: σ(α) = 1.0 for both branches (text disabled, DGTRS not loaded) ``` ### Text hierarchy (L1 / L2 / L3) Each drone image has a VLM-generated caption (Qwen3-VL) split into 3 levels: | Level | Name | Content | Typical length | |-------|------|---------|----------------| | **L1** | Overview | First sentence of P1: land-cover summary with class percentages | 15–30 tokens | | **L2** | Full description | Complete P1 (inventory) + P2 (spatial layout with 5+ zones) | 100–200 tokens | | **L3** | Fingerprint | P3: unique landmarks and spatial signature for matching | 20–50 tokens | All three levels are encoded by a **single DGTRS-CLIP ViT-L-14** text encoder (248-token context via KPS positional embedding, 768-dim output) adapted with **LoRA** (rank=4 on Q/V in all 12 blocks). ### Text fusion (shared MLP for both branches) ```math \mathbf{z}_{\text{text}} = \text{MLP}\bigl([\mathbf{z}_1 \;;\; \mathbf{z}_2 \;;\; \mathbf{z}_3]\bigr) ``` where `[z₁ ; z₂ ; z₃] ∈ ℝ^{B×2304}` is the concatenation of three 768-dim DGTRS-CLIP embeddings, and ```math \text{MLP}: \text{Linear}(2304, 1024) \to \text{GELU} \to \text{Linear}(1024, 1024), \quad \mathbf{z}_{\text{text}} \in \mathbb{R}^{B \times 1024} ``` ### Gated fusion (separate gates for query and gallery) ```math \mathbf{q} = \sigma(\alpha_q) \cdot \mathbf{d}_{\text{img}} + \bigl(1 - \sigma(\alpha_q)\bigr) \cdot \mathbf{d}_{\text{txt}} \qquad \text{(query branch)} ``` ```math \mathbf{g} = \sigma(\alpha_g) \cdot \mathbf{s}_{\text{img}} + \bigl(1 - \sigma(\alpha_g)\bigr) \cdot \mathbf{s}_{\text{txt}} \qquad \text{(gallery branch)} ``` - `α_q, α_g` — separate learnable scalars in logit-space, init `σ(α) ≈ 0.7` - `σ` — sigmoid function - `d_img, s_img ∈ ℝ^{B×1024}` — DINOv3+MONA image embeddings - `d_txt, s_txt ∈ ℝ^{B×1024}` — fused text embeddings - For satellite images without captions: `s_txt = None → g = s_img` ### Adaptation methods | Method | Applied to | Where | Params | |--------|-----------|-------|--------| | **MONA** (CVPR 2025) | DINOv3 ViT-L/16 (drone + sat) | After MSA and MLP in each of 24 blocks | 7.0M per encoder | | **LoRA** (rank=4) | DGTRS-CLIP text encoder | Q and V projections in all 12 blocks | 147K | **MONA adapter** (per block): ```math \mathbf{x} \leftarrow \mathbf{x} + \text{Up}_{64 \to 1024}\!\Bigl(\text{GELU}\bigl(\text{MonaOp}\bigl(\text{Down}_{1024 \to 64}(\hat{\mathbf{x}})\bigr)\bigr)\Bigr) ``` where `x̂ = γ · LN(x) + γₓ · x` (scaled LayerNorm, `γ` init `10⁻⁶`, `γₓ` init `1`) ```math \text{MonaOp}(\mathbf{x}) = \frac{\text{DWConv}_{3 \times 3}(\mathbf{x}) + \text{DWConv}_{5 \times 5}(\mathbf{x}) + \text{DWConv}_{7 \times 7}(\mathbf{x})}{3} + \mathbf{x} ``` **LoRA** (per attention layer): ```math \mathbf{Q}' = \mathbf{Q} + \frac{\alpha}{r} \cdot \mathbf{x} \mathbf{A}_Q^T \mathbf{B}_Q^T, \qquad \mathbf{V}' = \mathbf{V} + \frac{\alpha}{r} \cdot \mathbf{x} \mathbf{A}_V^T \mathbf{B}_V^T ``` where `A ∈ ℝ^{r×d}`, `B ∈ ℝ^{d×r}`, `r = 4` ### Loss function Symmetric InfoNCE with learnable temperature (CLIP-style `logit_scale`): ```math \mathcal{L} = w_{q \to g} \cdot \mathcal{L}_{q \to g} + w_{g \to q} \cdot \mathcal{L}_{g \to q} ``` ```math \mathcal{L}_{q \to g} = \text{CrossEntropy}\!\left(\frac{\hat{\mathbf{q}} \cdot \hat{\mathbf{g}}^T}{\tau},\; \text{targets}\right), \qquad \mathcal{L}_{g \to q} = \text{CrossEntropy}\!\left(\frac{\hat{\mathbf{g}} \cdot \hat{\mathbf{q}}^T}{\tau},\; \text{targets}\right) ``` - `τ = 1 / exp(logit_scale)` — learnable scalar, clamped `τ ∈ [0.01, 0.5]`, init `τ₀ = 0.07` - `w_{q→g} = 0.6`, `w_{g→q} = 0.4` - `targets = [0, 1, 2, ..., B−1]` — positives on diagonal - label smoothing `= 0.1` Loss and adapters run in **fp32** (AMP autocast disabled) to prevent gradient overflow. ### Metrics | Metric | Formula | Direction | |--------|---------|-----------| | **R@K** (Recall at K) | fraction of queries where correct gallery is in top-K | drone → satellite (primary) | | **Delta R@1** | R@1(with_text) − R@1(baseline) | higher = text helps | Reported: R@1, R@5, R@10 for both q→g and g→q directions. ### Optimizer & scheduler ``` Optimizer: AdamW - MONA adapters, TextFusionMLP, gate α_q, gate α_g, logit_scale: lr = 1e-4, weight_decay = 1e-4 - LoRA adapters (DGTRS-CLIP text encoder): lr = 1e-5 (10× lower, --text-lr-factor 0.1) Scheduler: Linear warmup (2 epochs) + cosine annealing - Per-step (not per-epoch) - warmup: lr linearly ramps from 0 to lr_max over warmup_steps - cosine: lr decays from lr_max to 0 over remaining steps Gradient clipping: max_norm = 1.0 Mixed precision: AMP fp16 for model forward, fp32 for loss ``` ### Augmentations | Transform | Drone (train) | Satellite (train) | Eval | |-----------|:---:|:---:|:---:| | RandomResizedCrop(256, scale=0.7–1.0) | ✓ | ✓ | — | | Resize(256) + CenterCrop(256) | — | — | ✓ | | RandomHorizontalFlip(0.5) | ✓ | ✓ | — | | RandomRotation(15°) | ✓ | — | — | | ColorJitter(0.3, 0.3, 0.2, 0.1) | ✓ | ✓ | — | | RandomGrayscale(0.05) | ✓ | ✓ | — | | GaussianBlur(k=3, σ=0.1–2.0) | ✓ | — | — | | ImageNet Normalize | ✓ | ✓ | ✓ | ### Model summary | Component | Params | Trainable | Notes | |-----------|--------|-----------|-------| | DINOv3 ViT-L/16 LVD (drone) | 303M | frozen | backbone weights frozen | | MONA adapters (drone) | 7.0M | 7.0M | 2 per block × 24 blocks, bottleneck=64 | | DINOv3 ViT-L/16 SAT (satellite) | 303M | frozen | backbone weights frozen | | MONA adapters (satellite) | 7.0M | 7.0M | 2 per block × 24 blocks, bottleneck=64 | | DGTRS-CLIP ViT-L-14 (text) | 124M | frozen | backbone weights frozen | | LoRA adapters (text) | 147K | 147K | Q+V, rank=4, 12 blocks | | TextFusionMLP (shared) | 3.4M | 3.4M | Linear(2304,1024) + GELU + Linear(1024,1024) | | GatedFusion α_q + α_g | 2 | 2 | separate gate scalars | | logit_scale | 1 | 1 | learnable temperature | | **Total** | **748M** | **17.6M (2.35%)** | retrieval dim = 1024 | ## Experiments ### V3 — GTA-UAV + DINOv3 + DGTRS-CLIP (active) **Dataset:** GTA-UAV-LR (33K drone + 14K satellite, GTA V synthetic) - RGB: `/home/servml/Документы/datasets/GTA-UAV-LR/` - Captions: `/home/servml/Документы/datasets/GTA-UAV-LR-captions/` (40K JSON, 3-paragraph VLM) - Segmentation: `/home/servml/Документы/datasets/GTA-UAV-LR-aug/` (17 classes) - Seg filter: 37,498 passed / 10,905 excluded (>=90% background+water) - Split: 80/20 random (26,966 train / 6,742 test → 24,891/6,252 after seg filter) ### V2 — UAV-GeoLoc + GeoRSCLIP (legacy) Single backbone with template captions. ``` Query: drone_img + caption -> GeoRSCLIP -> GatedFusion -> query Gallery: sat_img -> GeoRSCLIP -> gallery ``` **Dataset:** UAV-GeoLoc Terrain split (206K train queries) ## Structure ``` caption-test/ ├── conf/ # Gin configs │ ├── gtauav_balanced.gin # GTA-UAV with text (10 epochs, v3) │ ├── gtauav_baseline.gin # GTA-UAV baseline, no text (v3) │ ├── gtauav_text_heavy.gin # GTA-UAV text-heavy gate=0.3 (v3) │ ├── balanced.gin # UAV-GeoLoc with text (v2) │ ├── baseline_no_text.gin # UAV-GeoLoc baseline (v2) │ └── text_heavy.gin # UAV-GeoLoc text-heavy (v2) ├── nn_models/ # Pre-trained checkpoints (v3, gitignored) │ ├── DINO_WEB/ # DINOv3 ViT-L/16 LVD-1689M (.pth) │ ├── DINO_SAT/ # DINOv3 ViT-L/16 SAT-493M (.safetensors) │ └── LRSCLIP/ # DGTRS-CLIP ViT-L-14 (.pt) ├── meta/ # Generated metadata │ ├── train_80.json # 80% train split (26,966 pairs) │ ├── test_20.json # 20% test split (6,742 pairs) │ └── seg_filter.json # Segmentation filter results ├── scripts/ │ ├── make_split.py # Create 80/20 train/test split │ ├── filter_segmentation.py # Exclude 90%+ background/water images │ ├── compare_runs.py # Delta R@1 comparison report │ └── generate_captions.py # Offline caption generation ├── src/ │ ├── datasets/ │ │ ├── gtauav_dataset.py # GTA-UAV-LR loader + L1/L2/L3 parsing (v3) │ │ └── visloc_with_captions.py # UAV-GeoLoc loader (v2) │ ├── models/ │ │ ├── dgtrs/ # Official DGTRS-CLIP text encoder (Apache-2.0) │ │ │ ├── model.py # DGTRSTextEncoder, build_model, tokenize │ │ │ ├── simple_tokenizer.py # BPE tokenizer (248 tokens) │ │ │ └── bpe_simple_vocab_16e6.txt.gz │ │ ├── asymmetric_encoder.py # DINOv3 + DGTRS + GatedFusion (v3) │ │ └── dual_encoder.py # GeoRSCLIP + GatedFusion (v2) │ ├── losses/ │ │ └── multi_infonce.py # InfoNCE with learnable temperature │ ├── training/ │ │ ├── train_gtauav.py # Training loop GTA-UAV (v3) │ │ ├── train.py # Training loop UAV-GeoLoc (v2) │ │ ├── trackers.py # Unified tracker: W&B + TensorBoard │ │ ├── grad_monitor.py # Gradient norm monitoring per group │ │ ├── gradcam.py # Grad-CAM visualization for DINOv3 │ │ ├── profiling.py # PyTorch Profiler + torchinfo summary │ │ └── plot_metrics.py # Seaborn/matplotlib metric plots │ └── eval/ │ └── evaluate.py # R@K metrics, Delta R@1 └── checkpoints/ # GeoRSCLIP RS5M_ViT-B-32.pt (v2) ``` ## Prerequisites ``` torch>=2.0 safetensors coloredlogs tqdm ftfy regex gin-config Pillow numpy pandas matplotlib seaborn ``` ### Optional (for extended diagnostics) ``` wandb # Weights & Biases experiment tracking torchinfo # Model summary tables tensorboard # TensorBoard logging (included with torch) ``` ## Workflow (V3 — GTA-UAV) ### 1. Create 80/20 split and filter segmentation ```bash python -m scripts.make_split --output-dir meta python -m scripts.filter_segmentation --output meta/seg_filter.json ``` ### 2. Train with gin configs (recommended) ```bash # Baseline (no text, 10 epochs) python -m src.training.train_gtauav --config conf/gtauav_baseline.gin \ --filter-meta meta/seg_filter.json # With captions (L1/L2/L3, 10 epochs) python -m src.training.train_gtauav --config conf/gtauav_balanced.gin \ --filter-meta meta/seg_filter.json # Text-heavy (gate=0.3, 70% text weight) python -m src.training.train_gtauav --config conf/gtauav_text_heavy.gin \ --filter-meta meta/seg_filter.json ``` ### 3. Train without gin (CLI-only) ```bash python -m src.training.train_gtauav --baseline --filter-meta meta/seg_filter.json python -m src.training.train_gtauav --filter-meta meta/seg_filter.json ``` ### 4. Enable diagnostics ```bash # W&B + Grad-CAM + PyTorch Profiler python -m src.training.train_gtauav --config conf/gtauav_balanced.gin \ --filter-meta meta/seg_filter.json --wandb --gradcam --profile # Gin parameter overrides from CLI python -m src.training.train_gtauav --config conf/gtauav_balanced.gin \ --filter-meta meta/seg_filter.json \ --gin-param 'TrainConfigGTAUAV.batch_size=16' 'TrainConfigGTAUAV.epochs=20' ``` CLI flags (`--wandb`, `--gradcam`, `--profile`, `--epochs`, etc.) take priority over gin config. ### 5. Resume from checkpoint ```bash python -m src.training.train_gtauav --resume out/gtauav/with_text/ckpt_epoch004.pt \ --filter-meta meta/seg_filter.json ``` ### 6. Compare and get verdict ```bash python -m scripts.compare_runs \ --baseline_report out/gtauav/baseline/eval_report.json \ --full_report out/gtauav/with_text/eval_report.json \ --output out/gtauav/comparison.md ``` ### 7. View TensorBoard ```bash tensorboard --logdir out/gtauav/with_text/tb_logs ``` ## Diagnostics & Visualization | Tool | Flag | Output | Description | |------|------|--------|-------------| | **TensorBoard** | `--use-tb` (default on) | `{out}/tb_logs/` | Scalars, histograms, images | | **W&B** | `--wandb` | cloud | Full experiment tracking, Grad-CAM images | | **Grad-CAM** | `--gradcam` | `{out}/gradcam/` | DINOv3 attention heatmaps (drone + satellite) | | **PyTorch Profiler** | `--profile` | `{out}/profiler/` | Chrome trace, CUDA timeline, memory | | **torchinfo** | auto | `{out}/model_summary.txt` | Layer-by-layer parameter table | | **Gradient norms** | `--log-grad-norms` (default on) | TB/W&B | Per-group: MONA, LoRA, MLP, gates, tau | | **CSV + plots** | auto | `{out}/logs/` | train.csv, val.csv, PNG plots every epoch | ## Decision rule | Delta R@1 (drone→satellite) | Verdict | |---|---| | >= +3% | **PASS** — captions informative, proceed to NADEZHDA teacher | | +1% to +3% | MARGINAL — add VLM refinement, re-run | | 0 to +1% | WEAK — redesign caption pipeline | | < 0 | HARMFUL — critical bug | ## Code style - `from __future__ import annotations` everywhere - Type hints on all signatures - Google-style docstrings - English-only comments