#!/usr/bin/env python3 """ create_notebook.py — Generate clip_tutorial.ipynb Run this script to produce the tutorial notebook for the CLIP Pelatnas P2 competition. Requires: nbformat (included with jupyter) """ import nbformat as nbf nb = nbf.v4.new_notebook() nb.metadata = { "kernelspec": { "display_name": "Python 3", "language": "python", "name": "python3" }, "language_info": { "name": "python", "version": "3.10.0" } } cells = [] def md(source): cells.append(nbf.v4.new_markdown_cell(source)) def code(source): cells.append(nbf.v4.new_code_cell(source)) # ───────────────────────────────────────────────────────────────────────────── # Header # ───────────────────────────────────────────────────────────────────────────── md("""\ # CLIP Tutorial — Pelatnas IOAI 2026 P2 **Topik:** Multimodal Learning — CLIP (Contrastive Language-Image Pretraining) Notebook ini memandu kalian dari nol — memahami arsitektur CLIP, mengimplementasikannya dari scratch, sampai menggunakannya untuk menyelesaikan 4 task kompetisi ARIA. | Section | Topik | |---------|-------| | 1 | CLIP: Arsitektur dan Motivasi | | 2 | Mini CLIP dari Scratch (CIFAR-10) | | 3 | Load Pretrained CLIP + Eksplorasi Embedding Space | | 4 | Zero-Shot Classification | | 5 | Linear Probing | | 6 | Image-Text Retrieval | | 7 | MCQA dengan CLIP | | 8 | Baseline Submission | """) # ───────────────────────────────────────────────────────────────────────────── # Section 1 — CLIP Architecture # ───────────────────────────────────────────────────────────────────────────── md("""\ --- ## Section 1 — CLIP: Arsitektur dan Motivasi ### Mengapa CLIP? Model vision konvensional (ResNet, ViT) ditraining untuk memprediksi label dari dataset yang fixed (ImageNet → 1000 kelas). Masalahnya: - Tidak bisa generalize ke kelas baru tanpa retraining - Label harus predefined, tidak bisa deskripsi bebas **CLIP** (Contrastive Language-Image Pretraining, Radford et al. 2021) menyelesaikan ini dengan cara berbeda: instead of predicting labels, CLIP belajar *alignment* antara gambar dan teks. ### Dual-Stream Architecture CLIP terdiri dari dua encoder yang ditraining bersama: 1. **Image Encoder**: ViT atau ResNet → menghasilkan image embedding (vektor) 2. **Text Encoder**: Transformer → menghasilkan text embedding (vektor) Kedua encoder memproyeksikan input ke *shared embedding space* dengan dimensi yang sama (e.g., 512 untuk ViT-B/32). ### Training Objective CLIP ditraining dengan dataset **400 juta** pasang (image, caption) dari internet. Objective-nya sederhana: - image dan caption yang **matching** → cosine similarity **TINGGI** - image dan caption yang **tidak matching** → cosine similarity **RENDAH** Ini adalah *contrastive learning*: model belajar "mendekatkan" pasangan yang benar dan "menjauhkan" pasangan yang salah. """) code("""\ # ── Cell 1.1: Visualisasi konsep similarity matrix ────────────────────────── import numpy as np import matplotlib.pyplot as plt labels = ['cat', 'dog', 'car', 'ship', 'bird', 'horse'] N = len(labels) # Similarity matrix ideal: diagonal tinggi, off-diagonal rendah np.random.seed(42) sim_matrix = np.random.uniform(0.1, 0.4, (N, N)) np.fill_diagonal(sim_matrix, np.random.uniform(0.8, 0.95, N)) fig, ax = plt.subplots(figsize=(7, 6)) im = ax.imshow(sim_matrix, cmap='Blues', vmin=0, vmax=1) ax.set_xticks(range(N)) ax.set_yticks(range(N)) ax.set_xticklabels([f'"{l}"' for l in labels], rotation=45, ha='right') ax.set_yticklabels([f'[IMG {l}]' for l in labels]) ax.set_xlabel('Text Embeddings') ax.set_ylabel('Image Embeddings') ax.set_title('CLIP Similarity Matrix\\n(diagonal = matching pairs)') plt.colorbar(im) for i in range(N): for j in range(N): ax.text(j, i, f'{sim_matrix[i, j]:.2f}', ha='center', va='center', color='white' if sim_matrix[i, j] > 0.6 else 'black', fontsize=9) plt.tight_layout() plt.show() """) # ───────────────────────────────────────────────────────────────────────────── # Section 2 — Mini CLIP from Scratch # ───────────────────────────────────────────────────────────────────────────── md("""\ --- ## Section 2 — Mini CLIP dari Scratch ### Implementasi CLIP dari Nol Kita akan membuat versi miniatur CLIP untuk memahami mekanismenya. Ini **BUKAN** untuk performa — hanya untuk intuisi. Dataset toy: CIFAR-10 subset (1.000 images, 10 classes). Template caption: `"a photo of a {class_name}"`. Komponen yang diperlukan: 1. `TinyImageEncoder`: CNN sederhana → embedding 2. `TinyTextEncoder`: word embedding → pooling → linear 3. `InfoNCE Loss`: fungsi loss contrastive 4. Training loop + visualisasi """) code("""\ # ── Cell 2.1: Setup dan download CIFAR-10 ─────────────────────────────────── import torch import torch.nn as nn import torch.nn.functional as F from torchvision import datasets, transforms from torch.utils.data import DataLoader, Subset import numpy as np device = torch.device('cuda' if torch.cuda.is_available() else 'cpu') print(f"Using device: {device}") CIFAR10_CLASSES = ['airplane', 'automobile', 'bird', 'cat', 'deer', 'dog', 'frog', 'horse', 'ship', 'truck'] transform = transforms.Compose([ transforms.ToTensor(), transforms.Normalize((0.5, 0.5, 0.5), (0.5, 0.5, 0.5)) ]) full_train = datasets.CIFAR10(root='./data', train=True, download=True, transform=transform) # Ambil 100 images per class = 1000 total indices_per_class = {c: [] for c in range(10)} for idx, (_, label) in enumerate(full_train): if len(indices_per_class[label]) < 100: indices_per_class[label].append(idx) if all(len(v) == 100 for v in indices_per_class.values()): break all_indices = [idx for idxs in indices_per_class.values() for idx in idxs] toy_labels = [full_train.targets[i] for i in all_indices] toy_dataset = Subset(full_train, all_indices) print(f"Toy dataset size: {len(toy_dataset)} images") """) code("""\ # ── Cell 2.2: Tiny Image Encoder ──────────────────────────────────────────── class TinyImageEncoder(nn.Module): \"\"\" CNN sederhana: Conv → ReLU → MaxPool (×2) → GAP → Linear projection Input: (B, 3, 32, 32) Output: (B, EMBED_DIM) — normalized embedding \"\"\" def __init__(self, embed_dim=128): super().__init__() self.conv = nn.Sequential( nn.Conv2d(3, 32, kernel_size=3, padding=1), # → (B, 32, 32, 32) nn.ReLU(), nn.MaxPool2d(2), # → (B, 32, 16, 16) nn.Conv2d(32, 64, kernel_size=3, padding=1), # → (B, 64, 16, 16) nn.ReLU(), nn.MaxPool2d(2), # → (B, 64, 8, 8) ) self.projection = nn.Linear(64, embed_dim) def forward(self, x): x = self.conv(x) x = x.mean(dim=[2, 3]) # Global Average Pooling → (B, 64) x = self.projection(x) # (B, embed_dim) return F.normalize(x, dim=-1) # L2-normalize → unit sphere # ── Cell 2.3: Tiny Text Encoder ───────────────────────────────────────────── class TinyTextEncoder(nn.Module): \"\"\" Word embedding → mean pooling → Linear projection Input: token ids (B, seq_len) Output: (B, EMBED_DIM) — normalized embedding \"\"\" def __init__(self, vocab_size, embed_dim=128, hidden_dim=64): super().__init__() self.embedding = nn.Embedding(vocab_size, hidden_dim, padding_idx=0) self.projection = nn.Linear(hidden_dim, embed_dim) def forward(self, x): emb = self.embedding(x) # (B, seq_len, hidden_dim) pooled = emb.mean(dim=1) # mean pooling → (B, hidden_dim) out = self.projection(pooled) return F.normalize(out, dim=-1) """) code("""\ # ── Cell 2.4: Simple Tokenizer ─────────────────────────────────────────────── templates = [f"a photo of a {c}" for c in CIFAR10_CLASSES] all_words = set() for t in templates: all_words.update(t.split()) vocab = {word: idx + 1 for idx, word in enumerate(sorted(all_words))} vocab[''] = 0 def tokenize(text, max_len=8): tokens = [vocab.get(w, 0) for w in text.split()] tokens = tokens[:max_len] tokens += [0] * (max_len - len(tokens)) return tokens text_tokens = torch.tensor([tokenize(t) for t in templates]).to(device) # (10, 8) vocab_size = len(vocab) + 1 print("Vocabulary:", vocab) print("Template tokens shape:", text_tokens.shape) """) code("""\ # ── Cell 2.5: InfoNCE Loss ─────────────────────────────────────────────────── def info_nce_loss(image_emb, text_emb, temperature=0.07): \"\"\" Contrastive loss untuk batch of N image-text pairs. Intuisi: - Hitung similarity matrix N×N - Untuk setiap image, correct text-nya adalah di posisi diagonal - Cross-entropy: dorong diagonal jadi paling tinggi - Loss = rata-rata dua arah (image→text + text→image) \"\"\" logits = (image_emb @ text_emb.T) / temperature # (N, N) labels = torch.arange(len(image_emb)).to(image_emb.device) loss_i2t = F.cross_entropy(logits, labels) loss_t2i = F.cross_entropy(logits.T, labels) return (loss_i2t + loss_t2i) / 2 """) code("""\ # ── Cell 2.6: TinyCLIP model ──────────────────────────────────────────────── class TinyCLIP(nn.Module): def __init__(self, vocab_size, embed_dim=128): super().__init__() self.image_encoder = TinyImageEncoder(embed_dim) self.text_encoder = TinyTextEncoder(vocab_size, embed_dim) def encode_image(self, images): return self.image_encoder(images) def encode_text(self, tokens): return self.text_encoder(tokens) model = TinyCLIP(vocab_size=vocab_size, embed_dim=128).to(device) print(f"TinyCLIP parameters: {sum(p.numel() for p in model.parameters()):,}") """) code("""\ # ── Cell 2.7: Training loop ────────────────────────────────────────────────── optimizer = torch.optim.Adam(model.parameters(), lr=1e-3) images_tensor = torch.stack([toy_dataset[i][0] for i in range(len(toy_dataset))]) loader = DataLoader( list(zip(images_tensor, toy_labels)), batch_size=64, shuffle=True ) loss_history = [] NUM_EPOCHS = 10 for epoch in range(NUM_EPOCHS): model.train() epoch_losses = [] for images, labels in loader: images = images.to(device) labels_list = labels.tolist() if isinstance(labels, torch.Tensor) else labels batch_text = text_tokens[labels_list] # (B, 8) image_emb = model.encode_image(images) # (B, 128) text_emb = model.encode_text(batch_text) # (B, 128) loss = info_nce_loss(image_emb, text_emb) optimizer.zero_grad() loss.backward() optimizer.step() epoch_losses.append(loss.item()) mean_loss = np.mean(epoch_losses) loss_history.append(mean_loss) print(f"Epoch {epoch+1:2d}/{NUM_EPOCHS} | Loss: {mean_loss:.4f}") """) code("""\ # ── Cell 2.8: Plot loss curve ──────────────────────────────────────────────── import matplotlib.pyplot as plt plt.figure(figsize=(8, 4)) plt.plot(range(1, NUM_EPOCHS + 1), loss_history, marker='o', linewidth=2, color='steelblue') plt.xlabel('Epoch') plt.ylabel('InfoNCE Loss') plt.title('TinyCLIP Training Loss') plt.grid(True, alpha=0.3) plt.tight_layout() plt.show() """) code("""\ # ── Cell 2.9: Visualisasi embedding space (t-SNE) ─────────────────────────── from sklearn.manifold import TSNE model.eval() with torch.no_grad(): all_images = torch.stack([toy_dataset[i][0] for i in range(len(toy_dataset))]).to(device) image_embs = model.encode_image(all_images).cpu().numpy() text_embs = model.encode_text(text_tokens).cpu().numpy() all_embs = np.vstack([image_embs, text_embs]) # (1010, 128) tsne = TSNE(n_components=2, random_state=42, perplexity=30) embs_2d = tsne.fit_transform(all_embs) img_2d = embs_2d[:1000] txt_2d = embs_2d[1000:] colors = plt.cm.tab10(np.linspace(0, 1, 10)) fig, ax = plt.subplots(figsize=(10, 8)) for c in range(10): mask = np.array(toy_labels) == c ax.scatter(img_2d[mask, 0], img_2d[mask, 1], c=[colors[c]], alpha=0.4, s=20, label=CIFAR10_CLASSES[c]) ax.scatter(txt_2d[c, 0], txt_2d[c, 1], c=[colors[c]], marker='*', s=300, edgecolors='black', linewidths=1) ax.legend(loc='upper right', fontsize=8) ax.set_title('t-SNE: TinyCLIP Embedding Space\\n' '(dots = images, stars = text templates)') ax.axis('off') plt.tight_layout() plt.show() """) # ───────────────────────────────────────────────────────────────────────────── # Section 3 — Load Pretrained CLIP # ───────────────────────────────────────────────────────────────────────────── md("""\ --- ## Section 3 — Load Pretrained CLIP + Eksplorasi Embedding Space ### Dari Scratch ke Pretrained TinyCLIP kita ditraining di 1.000 gambar selama beberapa menit. CLIP asli ditraining di **400 juta** pasang selama berbulan-bulan di ratusan GPU. Hasilnya sangat berbeda. Mari kita load pretrained CLIP dan lihat embedding space-nya. **`openai/clip-vit-b-32`:** - Image encoder: Vision Transformer ViT-B/32 - Text encoder: Transformer 12 layers - Embedding dim: 512 - Total parameters: ~150M """) code("""\ # ── Cell 3.1: Install dan load CLIP ───────────────────────────────────────── # !pip install git+https://github.com/openai/CLIP.git # jalankan sekali jika belum import clip from PIL import Image import torch import numpy as np import matplotlib.pyplot as plt device = torch.device('cuda' if torch.cuda.is_available() else 'cpu') model_clip, preprocess = clip.load("ViT-B/32", device=device) model_clip.eval() print(f"Model loaded. Input resolution: {model_clip.visual.input_resolution}") print(f"Embedding dimension: {model_clip.visual.output_dim}") """) code("""\ # ── Cell 3.2: Load STL-10 test images ─────────────────────────────────────── from torchvision import datasets from torchvision.transforms import Compose, Resize, CenterCrop, ToTensor, Normalize clip_preprocess = Compose([ Resize(224), CenterCrop(224), ToTensor(), Normalize((0.48145466, 0.4578275, 0.40821073), (0.26862954, 0.26130258, 0.27577711)) ]) stl10_test = datasets.STL10(root='./data', split='test', download=True, transform=clip_preprocess) STL10_CLASSES = stl10_test.classes print(f"STL-10 classes: {STL10_CLASSES}") # Ambil 20/class untuk zero-shot (200 total) dan 20/class untuk linear probing (200 total) from collections import defaultdict zs_imgs, zs_labels = [], [] lp_imgs, lp_labels = [], [] zs_count = defaultdict(int) lp_count = defaultdict(int) for idx in range(len(stl10_test)): img, label = stl10_test[idx] if zs_count[label] < 20: zs_imgs.append(img) zs_labels.append(label) zs_count[label] += 1 elif lp_count[label] < 20: lp_imgs.append(img) lp_labels.append(label) lp_count[label] += 1 if sum(zs_count.values()) == 200 and sum(lp_count.values()) == 200: break zs_labels_arr = np.array(zs_labels) lp_test_labels = np.array(lp_labels) print(f"ZS set: {len(zs_imgs)} | LP test set: {len(lp_imgs)}") """) code("""\ # ── Cell 3.3: Extract CLIP image embeddings ────────────────────────────────── from torch.utils.data import DataLoader, TensorDataset def extract_embeddings(img_list, batch_size=64): \"\"\"Extract CLIP image embeddings dari list of tensors.\"\"\" all_embs = [] for i in range(0, len(img_list), batch_size): batch = torch.stack(img_list[i:i + batch_size]).to(device) with torch.no_grad(): emb = model_clip.encode_image(batch) emb = emb / emb.norm(dim=-1, keepdim=True) all_embs.append(emb.cpu()) return torch.cat(all_embs).numpy() print("Extracting embeddings...") zs_embeddings = extract_embeddings(zs_imgs) lp_test_embeddings = extract_embeddings(lp_imgs) print(f"Zero-shot embeddings: {zs_embeddings.shape}") print(f"Linear probing test embeddings: {lp_test_embeddings.shape}") """) code("""\ # ── Cell 3.4: Extract text embeddings untuk 10 kelas ──────────────────────── def get_text_embeddings(class_names, template="a photo of a {}"): \"\"\"Encode class names dengan text encoder CLIP.\"\"\" prompts = [template.format(c) for c in class_names] tokens = clip.tokenize(prompts).to(device) with torch.no_grad(): text_emb = model_clip.encode_text(tokens) text_emb = text_emb / text_emb.norm(dim=-1, keepdim=True) return text_emb.cpu().numpy() text_embeddings = get_text_embeddings(STL10_CLASSES) print(f"Text embeddings: {text_embeddings.shape}") # (10, 512) """) code("""\ # ── Cell 3.5: Visualisasi t-SNE ───────────────────────────────────────────── from sklearn.manifold import TSNE all_embs = np.vstack([zs_embeddings, text_embeddings]) # (210, 512) tsne = TSNE(n_components=2, random_state=42, perplexity=30) embs_2d = tsne.fit_transform(all_embs) img_2d = embs_2d[:200] txt_2d = embs_2d[200:] colors = plt.cm.tab10(np.linspace(0, 1, 10)) fig, ax = plt.subplots(figsize=(12, 9)) for c in range(10): mask = zs_labels_arr == c ax.scatter(img_2d[mask, 0], img_2d[mask, 1], c=[colors[c]], alpha=0.5, s=30, label=STL10_CLASSES[c]) ax.scatter(txt_2d[c, 0], txt_2d[c, 1], c=[colors[c]], marker='*', s=500, edgecolors='black', linewidths=1.5) ax.legend(loc='upper right', fontsize=9) ax.set_title('Pretrained CLIP — Embedding Space (STL-10)\\n' 'Dots = image embeddings | Stars = text template embeddings', fontsize=12) ax.axis('off') plt.tight_layout() plt.show() """) # ───────────────────────────────────────────────────────────────────────────── # Section 4 — Zero-Shot Classification # ───────────────────────────────────────────────────────────────────────────── md("""\ --- ## Section 4 — Zero-Shot Classification ### Cara Kerja Zero-Shot dengan CLIP 1. Encode setiap class name menjadi text embedding 2. Encode query image menjadi image embedding 3. Hitung cosine similarity antara image dan semua class embeddings 4. Prediksi = class dengan similarity tertinggi **Prompt engineering penting!** `"dog"` ≠ `"a photo of a dog"` ≠ `"a high-quality photo of a dog, DSLR"` """) code("""\ # ── Cell 4.1: Zero-shot prediction ────────────────────────────────────────── # zs_embeddings dan text_embeddings sudah dihitung di Section 3 similarity = zs_embeddings @ text_embeddings.T # (200, 10) predictions_idx = np.argmax(similarity, axis=1) predictions_str = [STL10_CLASSES[i] for i in predictions_idx] accuracy = np.mean(predictions_idx == zs_labels_arr) print(f"Zero-shot accuracy: {accuracy:.4f} ({accuracy*100:.1f}%)") """) code("""\ # ── Cell 4.2: Pengaruh prompt engineering ──────────────────────────────────── templates_to_compare = [ "{}", "a photo of a {}", "a photo of a {}, high quality", "a {} in the wild", ] print("\\nPrompt engineering comparison:") print("-" * 50) for template in templates_to_compare: text_emb = get_text_embeddings(STL10_CLASSES, template) sim = zs_embeddings @ text_emb.T preds = np.argmax(sim, axis=1) acc = np.mean(preds == zs_labels_arr) print(f" {template:<40} → {acc*100:.1f}%") """) code("""\ # ── Cell 4.3: Confusion matrix ─────────────────────────────────────────────── from sklearn.metrics import confusion_matrix, ConfusionMatrixDisplay cm = confusion_matrix(zs_labels_arr, predictions_idx) disp = ConfusionMatrixDisplay(confusion_matrix=cm, display_labels=STL10_CLASSES) fig, ax = plt.subplots(figsize=(10, 8)) disp.plot(ax=ax, colorbar=False, cmap='Blues') ax.set_title('Zero-Shot Classification — Confusion Matrix') plt.xticks(rotation=45, ha='right') plt.tight_layout() plt.show() """) code("""\ # ── Cell 4.4: Per-class accuracy ───────────────────────────────────────────── per_class_acc = {} for c in range(10): mask = zs_labels_arr == c per_class_acc[STL10_CLASSES[c]] = np.mean(predictions_idx[mask] == c) print("\\nPer-class accuracy:") for cls, acc in sorted(per_class_acc.items(), key=lambda x: -x[1]): bar = '█' * int(acc * 20) print(f" {cls:<10} {acc*100:5.1f}% {bar}") """) # ───────────────────────────────────────────────────────────────────────────── # Section 5 — Linear Probing # ───────────────────────────────────────────────────────────────────────────── md("""\ --- ## Section 5 — Linear Probing ### Perbedaan dari Zero-Shot | Metode | Data berlabel? | Cara prediksi | |--------|---------------|---------------| | Zero-shot | Tidak | Text prompts | | Linear probing | Ya (sedikit) | Classifier di atas frozen embeddings | **Kenapa tidak fine-tune semua layer?** - Linear probing murah secara komputasi - Menguji seberapa "baik" embeddings CLIP tanpa tambahan supervision - Fine-tuning bisa overfit ke domain kecil """) code("""\ # ── Cell 5.1: Extract train embeddings untuk linear probing ───────────────── stl10_train = datasets.STL10(root='./data', split='train', download=True, transform=clip_preprocess) # Ambil 100/class = 1000 images untuk training train_imgs, train_labels = [], [] count = defaultdict(int) for idx in range(len(stl10_train)): img, label = stl10_train[idx] if count[label] < 100: train_imgs.append(img) train_labels.append(label) count[label] += 1 if sum(count.values()) == 1000: break train_labels_arr = np.array(train_labels) print("Extracting train embeddings...") lp_train_embeddings = extract_embeddings(train_imgs) print(f"Train embeddings: {lp_train_embeddings.shape}") """) code("""\ # ── Cell 5.2: Train classifier ─────────────────────────────────────────────── from sklearn.linear_model import LogisticRegression clf = LogisticRegression(max_iter=1000, C=0.316, random_state=42) clf.fit(lp_train_embeddings, train_labels_arr) lp_predictions = clf.predict(lp_test_embeddings) lp_accuracy = np.mean(lp_predictions == lp_test_labels) print(f"Linear probing accuracy: {lp_accuracy:.4f} ({lp_accuracy*100:.1f}%)") """) code("""\ # ── Cell 5.3: Perbandingan zero-shot vs linear probing ─────────────────────── print("\\n" + "="*50) print(" Perbandingan: Zero-Shot vs Linear Probing") print("="*50) print(f" Zero-shot (0 training images) : {accuracy*100:5.1f}%") print(f" Linear probe (1.000 labeled imgs) : {lp_accuracy*100:5.1f}%") print(f" Gap: +{(lp_accuracy - accuracy)*100:.1f}%") print("="*50) """) code("""\ # ── Cell 5.4: Bar chart per-class comparison ───────────────────────────────── per_class_lp = {} for c in range(10): mask = lp_test_labels == c per_class_lp[STL10_CLASSES[c]] = np.mean(lp_predictions[mask] == c) fig, ax = plt.subplots(figsize=(12, 5)) x = np.arange(10) w = 0.35 zs_vals = [per_class_acc[c] for c in STL10_CLASSES] lp_vals = [per_class_lp[c] for c in STL10_CLASSES] ax.bar(x - w/2, zs_vals, w, label='Zero-shot', color='steelblue', alpha=0.8) ax.bar(x + w/2, lp_vals, w, label='Linear probe', color='coral', alpha=0.8) ax.set_xticks(x) ax.set_xticklabels(STL10_CLASSES, rotation=45, ha='right') ax.set_ylabel('Accuracy') ax.set_title('Per-Class Accuracy: Zero-Shot vs Linear Probing') ax.legend() ax.set_ylim(0, 1.05) ax.grid(True, axis='y', alpha=0.3) plt.tight_layout() plt.show() """) # ───────────────────────────────────────────────────────────────────────────── # Section 6 — Image-Text Retrieval # ───────────────────────────────────────────────────────────────────────────── md("""\ --- ## Section 6 — Image-Text Retrieval ### Retrieval sebagai Task Matching CLIP sangat natural untuk retrieval: 1. Encode query image → image embedding 2. Encode semua candidate captions → text embeddings 3. Similarity = cosine similarity 4. Predict = candidate dengan similarity tertinggi Dalam competition: **4 candidates per query**, predict index 0–3. """) code("""\ # ── Cell 6.1: Load Flickr8k test data ──────────────────────────────────────── import pandas as pd from PIL import Image as PILImage DATASET_ROOT = '/kaggle/input/clip-pelatnas-p2' candidates_df = pd.read_csv(f'{DATASET_ROOT}/test/retrieval/candidates.csv') print(f"Retrieval test: {len(candidates_df)} queries") print(candidates_df.head(2)) """) code("""\ # ── Cell 6.2: CLIP retrieval pipeline ──────────────────────────────────────── def clip_retrieval(image_path, captions, model, preprocess, device): \"\"\" Predict correct caption index untuk satu query. Returns: (predicted_idx, similarities_array) \"\"\" image = preprocess(PILImage.open(image_path)).unsqueeze(0).to(device) with torch.no_grad(): img_emb = model.encode_image(image) img_emb = img_emb / img_emb.norm(dim=-1, keepdim=True) tokens = clip.tokenize(captions, truncate=True).to(device) with torch.no_grad(): txt_emb = model.encode_text(tokens) txt_emb = txt_emb / txt_emb.norm(dim=-1, keepdim=True) similarities = (img_emb @ txt_emb.T).squeeze().cpu().numpy() predicted_idx = int(np.argmax(similarities)) return predicted_idx, similarities """) code("""\ # ── Cell 6.3: Batch evaluation ──────────────────────────────────────────────── base_path = f'{DATASET_ROOT}/test/retrieval/queries/' predictions_ret = [] for _, row in candidates_df.iterrows(): captions = [row[f'caption_{i}'] for i in range(4)] pred_idx, _ = clip_retrieval( base_path + row['image_path'], captions, model_clip, preprocess, device ) predictions_ret.append(pred_idx) predictions_ret = np.array(predictions_ret) correct_idx = candidates_df['correct_idx'].values ret_accuracy = np.mean(predictions_ret == correct_idx) print(f"Retrieval accuracy (4-way): {ret_accuracy:.4f} ({ret_accuracy*100:.1f}%)") print(f"Random baseline: 25.0%") """) code("""\ # ── Cell 6.4: Qualitative examples ─────────────────────────────────────────── fig, axes = plt.subplots(2, 4, figsize=(16, 7)) correct_mask = predictions_ret == correct_idx correct_examples = np.where(correct_mask)[0][:2] wrong_examples = np.where(~correct_mask)[0][:2] examples = list(correct_examples) + list(wrong_examples) for col, idx in enumerate(examples): row_data = candidates_df.iloc[idx] captions = [row_data[f'caption_{i}'] for i in range(4)] _, sims = clip_retrieval( base_path + row_data['image_path'], captions, model_clip, preprocess, device ) img = PILImage.open(base_path + row_data['image_path']) axes[0, col].imshow(img) axes[0, col].set_title('Benar' if col < 2 else 'Salah', color='green' if col < 2 else 'red', fontsize=12) axes[0, col].axis('off') for i, (cap, sim) in enumerate(zip(captions, sims)): is_correct = (i == row_data['correct_idx']) is_wrong = (i == predictions_ret[idx] and not is_correct) color = 'green' if is_correct else ('red' if is_wrong else 'black') marker = '★' if is_correct else ('✗' if is_wrong else ' ') axes[1, col].text(0.02, 0.88 - i * 0.23, f"{marker} [{sim:.2f}] {cap[:55]}...", transform=axes[1, col].transAxes, fontsize=7, color=color) axes[1, col].axis('off') plt.suptitle('Retrieval Examples (★ = correct answer, ✗ = wrong prediction)', fontsize=12) plt.tight_layout() plt.show() """) # ───────────────────────────────────────────────────────────────────────────── # Section 7 — MCQA # ───────────────────────────────────────────────────────────────────────────── md("""\ --- ## Section 7 — MCQA dengan CLIP ### Keterbatasan CLIP untuk Reasoning Cara naive dengan CLIP: - Encode image - Untuk setiap pilihan jawaban: encode `"Question: {q} Answer: {choice}"` - Predict = pilihan dengan similarity tertinggi terhadap image **Limitation**: CLIP tidak didesain untuk reasoning bertahap. CLIP bagus di *"apa yang ada di gambar ini?"* tapi terbatas untuk *"kenapa hal ini terjadi?"* atau soal sains yang butuh domain knowledge. """) code("""\ # ── Cell 7.1: Load ScienceQA test data ────────────────────────────────────── mcqa_df = pd.read_csv(f'{DATASET_ROOT}/test/mcqa/test.csv') print(f"MCQA test: {len(mcqa_df)} questions") print(mcqa_df.head(2)) """) code("""\ # ── Cell 7.2: CLIP MCQA pipeline ───────────────────────────────────────────── def clip_mcqa(image_path, question, choices, model, preprocess, device): \"\"\" Predict correct answer untuk MCQA. Strategi: encode image, bandingkan dengan "Question: {q} Answer: {choice}". \"\"\" image = preprocess(PILImage.open(image_path)).unsqueeze(0).to(device) with torch.no_grad(): img_emb = model.encode_image(image) img_emb = img_emb / img_emb.norm(dim=-1, keepdim=True) texts = [f"Question: {question} Answer: {c}" for c in choices] tokens = clip.tokenize(texts, truncate=True).to(device) with torch.no_grad(): txt_emb = model.encode_text(tokens) txt_emb = txt_emb / txt_emb.norm(dim=-1, keepdim=True) similarities = (img_emb @ txt_emb.T).squeeze().cpu().numpy() predicted_idx = int(np.argmax(similarities)) letter_map = {0: 'A', 1: 'B', 2: 'C', 3: 'D', 4: 'E'} return letter_map[predicted_idx], similarities """) code("""\ # ── Cell 7.3: Batch evaluation ──────────────────────────────────────────────── base_path_mcqa = f'{DATASET_ROOT}/test/mcqa/images/' predictions_mcqa = [] for _, row in mcqa_df.iterrows(): n_choices = int(row['num_choices']) choices = [row[f'choice_{chr(65+i)}'] for i in range(n_choices)] pred_letter, _ = clip_mcqa( base_path_mcqa + row['image_path'], row['question'], choices, model_clip, preprocess, device ) predictions_mcqa.append(pred_letter) mcqa_accuracy = np.mean(np.array(predictions_mcqa) == mcqa_df.get('answer', pd.Series([])).values) \ if 'answer' in mcqa_df.columns else float('nan') print(f"MCQA accuracy: {mcqa_accuracy:.4f} ({mcqa_accuracy*100:.1f}%)" if not np.isnan(mcqa_accuracy) else "MCQA predictions done (answer column not available in test set)") print(f"Random baseline (~3.5 choices avg): ~{100/3.5:.1f}%") """) code("""\ # ── Cell 7.4: Analysis per subject ─────────────────────────────────────────── mcqa_df_copy = mcqa_df.copy() mcqa_df_copy['predicted'] = predictions_mcqa if 'subject' in mcqa_df_copy.columns and 'answer' in mcqa_df_copy.columns: mcqa_df_copy['correct'] = mcqa_df_copy['predicted'] == mcqa_df_copy['answer'] subject_acc = mcqa_df_copy.groupby('subject')['correct'].mean().sort_values(ascending=False) print("Accuracy per subject:") for subj, acc in subject_acc.items(): bar = '█' * int(acc * 20) print(f" {subj:<25} {acc*100:5.1f}% {bar}") else: subj_counts = mcqa_df_copy.groupby('subject')['predicted'].count() print("Question count per subject:") for subj, cnt in subj_counts.items(): print(f" {subj:<25} {cnt} questions") """) # ───────────────────────────────────────────────────────────────────────────── # Section 8 — Baseline Submission # ───────────────────────────────────────────────────────────────────────────── md("""\ --- ## Section 8 — Baseline Submission ### Membuat Submission Kode berikut menggabungkan prediksi dari semua 4 task ke dalam satu CSV. Ini adalah baseline paling sederhana: semua task menggunakan zero-shot CLIP. **Estimasi skor baseline: ~70–80% overall accuracy.** Cara improve: - Prompt engineering yang lebih baik - Gunakan model CLIP yang lebih besar (ViT-L/14) - Fine-tuning CLIP untuk task tertentu - Ensemble dengan model multimodal lain (BLIP, SigLIP) """) code("""\ # ── Cell 8.1: Compile semua prediksi ───────────────────────────────────────── import pandas as pd sample_sub = pd.read_csv(f'{DATASET_ROOT}/sample_submission.csv') pred_map = {} # Zero-shot predictions (dari Section 4) zs_ids = [f'zs_{i:04d}' for i in range(1, 201)] for id_, pred in zip(zs_ids, predictions_str): pred_map[id_] = pred # Linear probing predictions (dari Section 5) lp_ids = [f'lp_{i:04d}' for i in range(1, 201)] lp_cls_str = [STL10_CLASSES[p] for p in lp_predictions] for id_, pred in zip(lp_ids, lp_cls_str): pred_map[id_] = pred # Retrieval predictions (dari Section 6) for id_, pred in zip(candidates_df['id'].values, predictions_ret.tolist()): pred_map[id_] = int(pred) # MCQA predictions (dari Section 7) for id_, pred in zip(mcqa_df['id'].values, predictions_mcqa): pred_map[id_] = pred """) code("""\ # ── Cell 8.2: Generate submission ──────────────────────────────────────────── submission = sample_sub.copy() submission['prediction'] = submission['id'].map(pred_map) assert len(submission) == 800, f"Expected 800 rows, got {len(submission)}" assert submission['prediction'].isna().sum() == 0, "Ada id yang tidak terprediksi!" print("Submission preview (2 per task):") for prefix in ['zs', 'lp', 'ret', 'mcqa']: mask = submission['id'].str.startswith(prefix) print(submission[mask].head(2).to_string(index=False)) print() submission.to_csv('submission.csv', index=False) print(f"Saved: submission.csv ({len(submission)} rows)") """) code("""\ # ── Cell 8.3: Sanity check ──────────────────────────────────────────────────── print("Distribusi prediksi per task:\\n") for prefix, name in [('zs', 'Zero-shot'), ('lp', 'Linear probe'), ('ret', 'Retrieval'), ('mcqa', 'MCQA')]: mask = submission['id'].str.startswith(prefix) subset = submission[mask] counts = subset['prediction'].value_counts().to_dict() print(f" {name} ({mask.sum()} items): {counts}") """) # ───────────────────────────────────────────────────────────────────────────── # Write notebook # ───────────────────────────────────────────────────────────────────────────── nb.cells = cells with open('clip_tutorial.ipynb', 'w', encoding='utf-8') as f: nbf.write(nb, f) print("clip_tutorial.ipynb created successfully!") print(f"Cells: {len(cells)} total")