--- pipeline_tag: image-classification license: apache-2.0 base_model: OpenGVLab/pvt_v2_b2 library_name: zeromodels tags: - keras - zeromodels - image-classification - pvt-v2 - backbone - arxiv:2106.13797 - pytorch - jax - tf --- ## ***See [our collection](https://huggingface.co/collections/zeromodels/pvt-and-pvtv2-6a90e9dd0a2b03a982d0b876) for all PVT and PVTv2 versions.*** # Run PVTv2 with Keras 3: JAX, PyTorch, or TensorFlow [![GitHub](https://img.shields.io/badge/GitHub-ZeroModels-black?logo=github)](https://github.com/IMvision12/ZeroModels) [![Docs](https://img.shields.io/badge/Docs-PVTv2-blue)](https://imvision12.github.io/ZeroModels/pvt_v2/) [![Collection](https://img.shields.io/badge/HF-PVTv2%20collection-yellow)](https://huggingface.co/collections/zeromodels/pvt-and-pvtv2-6a90e9dd0a2b03a982d0b876) # zeromodels/pvt-v2-b2 Paper: [PVTv2: Improved Baselines with Pyramid Vision Transformer (arXiv:2106.13797)](https://arxiv.org/abs/2106.13797) · [HF Papers](https://huggingface.co/papers/2106.13797) PVTv2 improves PVT with overlapping patch embeddings, a convolutional feed-forward network, and no position embeddings (so any input resolution works), plus an optional linear-attention variant. Use `PvtV2ImageClassify` for logits or `PvtV2Model` for tokens / per-stage features via `as_backbone=True`. - Parameters: ~25.4M - ImageNet-1k top-1: **82.0%** For more details on the model, see the upstream [model card](https://huggingface.co/OpenGVLab/pvt_v2_b2). Pure-**Keras 3** conversion of [`OpenGVLab/pvt_v2_b2`](https://huggingface.co/OpenGVLab/pvt_v2_b2) for [zeromodels](https://github.com/IMvision12/ZeroModels). One implementation runs unmodified on **TensorFlow / Torch / JAX**. This is an **image-classification / backbone** checkpoint (`PvtV2ImageClassify` / `PvtV2Model`). ## ✨ Quick start ```python import os os.environ["KERAS_BACKEND"] = "torch" # or "jax" / "tensorflow" from PIL import Image import numpy as np from zeromodels.models.pvt_v2 import PvtV2ImageClassify, PvtV2Model model = PvtV2ImageClassify.from_weights("zeromodels/pvt-v2-b2") backbone = PvtV2Model.from_weights("zeromodels/pvt-v2-b2", as_backbone=True) image = Image.open("your_image.jpg").convert("RGB").resize((224, 224)) x = np.asarray(image, dtype="float32")[None] # (1, H, W, 3), raw [0, 255] print(model(x).shape) # (1, num_classes) feats = backbone(x) print(len(feats), [tuple(f.shape) for f in feats]) # 4-stage feature pyramid ``` Normalization is baked into the graph, so pass raw `[0, 255]` pixels. Load any PVTv2 variant the same way with `from_weights("zeromodels/")`: | Variant | ImageNet-1k top-1 | Hub | |---|---|---| | `pvt-v2-b0` | 70.5% | [`zeromodels/pvt-v2-b0`](https://huggingface.co/zeromodels/pvt-v2-b0) | | `pvt-v2-b1` | 78.7% | [`zeromodels/pvt-v2-b1`](https://huggingface.co/zeromodels/pvt-v2-b1) | | `pvt-v2-b2` | 82.0% | [`zeromodels/pvt-v2-b2`](https://huggingface.co/zeromodels/pvt-v2-b2) | | `pvt-v2-b2-linear` | 82.1% | [`zeromodels/pvt-v2-b2-linear`](https://huggingface.co/zeromodels/pvt-v2-b2-linear) | | `pvt-v2-b3` | 83.1% | [`zeromodels/pvt-v2-b3`](https://huggingface.co/zeromodels/pvt-v2-b3) | | `pvt-v2-b4` | 83.6% | [`zeromodels/pvt-v2-b4`](https://huggingface.co/zeromodels/pvt-v2-b4) | | `pvt-v2-b5` | 83.8% | [`zeromodels/pvt-v2-b5`](https://huggingface.co/zeromodels/pvt-v2-b5) | ## Tips - Set `KERAS_BACKEND` **before** importing Keras / zeromodels. - `PvtV2ImageClassify` returns class logits; `PvtV2Model` returns features (`as_backbone=True` for the four-stage pyramid). - Both the model and its data format (`channels_last` / `channels_first`) are supported and bit-exact. - See the [docs](https://imvision12.github.io/ZeroModels/pvt_v2/) and [Loading Weights](https://imvision12.github.io/ZeroModels/loading_weights/). - Upstream checkpoints load directly: `PvtV2ImageClassify.from_weights("hf:OpenGVLab/pvt_v2_b2")`. ## Special Thanks A huge thank you to the PVT authors ([whai362/PVT](https://github.com/whai362/PVT)) and the Hugging Face community for creating and releasing these models. License: see the YAML `license` above (matches the upstream checkpoint).