Add model card content and `transformers` library tag

README.md

@@ -1,5 +1,6 @@
 ---
-license: mit
+base_model:
+- OpenGVLab/InternVL2_5-8B
 datasets:
 - lmms-lab/RefCOCO
 - lmms-lab/RefCOCOplus
@@ -7,10 +8,9 @@ datasets:
 - qixiangbupt/grefcoco
 language:
 - en
+license: mit
 metrics:
 - accuracy
-base_model:
-- OpenGVLab/InternVL2_5-8B
 pipeline_tag: image-segmentation
 tags:
 - Visual Grounding
@@ -18,4 +18,196 @@ tags:
 - Generalized Referring Expression Segmentation
 - Referring Expression Comprehension
 new_version: jcwang0602/MLLMSeg_InternVL2_5_8B_RES
----
+library_name: transformers
+---
+
+# MLLMSeg: Unlocking the Potential of MLLMs in Referring Expression Segmentation via a Light-weight Mask Decoder
+
+This repository contains the `MLLMSeg_InternVL2_5_8B_RES` model presented in the paper [Unlocking the Potential of MLLMs in Referring Expression Segmentation via a Light-weight Mask Decoder](https://huggingface.co/papers/2508.04107).
+
+**Abstract:**
+Reference Expression Segmentation (RES) aims to segment image regions specified by referring expressions and has become popular with the rise of multimodal large models (MLLMs). While MLLMs excel in semantic understanding, their token-generation paradigm struggles with pixel-level dense prediction. Existing RES methods either couple MLLMs with the parameter-heavy Segment Anything Model (SAM) with 632M network parameters or adopt SAM-free lightweight pipelines that sacrifice accuracy. To address the trade-off between performance and cost, we specifically propose MLLMSeg, a novel framework that fully exploits the inherent visual detail features encoded in the MLLM vision encoder without introducing an extra visual encoder. Besides, we propose a detail-enhanced and semantic-consistent feature fusion module (DSFF) that fully integrates the detail-related visual feature with the semantic-related feature output by the large language model (LLM) of MLLM. Finally, we establish a light-weight mask decoder with only 34M network parameters that optimally leverages detailed spatial features from the visual encoder and semantic features from the LLM to achieve precise mask prediction. Extensive experiments demonstrate that our method generally surpasses both SAM-based and SAM-free competitors, striking a better balance between performance and cost.
+
+<img src="https://raw.githubusercontent.com/jcwang0602/MLLMSeg/main/assets/method.png" width="800">
+
+**Code:** Find the official implementation and full details on GitHub: [https://github.com/jcwang0602/MLLMSeg](https://github.com/jcwang0602/MLLMSeg)
+**ArXiv:** [http://arxiv.org/abs/2508.04107](http://arxiv.org/abs/2508.04107)
+
+---
+
+## Quick Start
+
+This section provides instructions on how to inference our pre-trained models.
+
+**Notes:** Our models accept images of any size as input. The model outputs are normalized to relative coordinates within a 0-1000 range (either a center point or a bounding box defined by top-left and bottom-right coordinates). For visualization, please remember to convert these relative coordinates back to the original image dimensions.
+
+### Installation
+
+First, install the `transformers` library and other necessary dependencies as specified by the original repository:
+
+```bash
+conda create -n mllmseg python==3.10.18 -y
+conda activate mllmseg
+pip install torch==2.5.1 torchvision==0.20.1 --index-url https://download.pytorch.org/whl/cu118
+# If you encounter any problems during the installation of datasets, please install this first.
+# conda install -c conda-forge pyarrow
+pip install -r requirements.txt
+pip install flash-attn==2.3.6 --no-build-isolation # Note: need gpu to install
+```
+
+### Inference Example
+
+```python
+import numpy as np
+import torch
+import torchvision.transforms as T
+from PIL import Image
+from torchvision.transforms.functional import InterpolationMode
+from transformers import AutoModel, AutoTokenizer
+import os
+
+IMAGENET_MEAN = (0.485, 0.456, 0.406)
+IMAGENET_STD = (0.229, 0.224, 0.225)
+
+def build_transform(input_size):
+    MEAN, STD = IMAGENET_MEAN, IMAGENET_STD
+    transform = T.Compose([
+        T.Lambda(lambda img: img.convert('RGB') if img.mode != 'RGB' else img),
+        T.Resize((input_size, input_size), interpolation=InterpolationMode.BICUBIC),
+        T.ToTensor(),
+        T.Normalize(mean=MEAN, std=STD)
+    ])
+    return transform
+
+def find_closest_aspect_ratio(aspect_ratio, target_ratios, width, height, image_size):
+    best_ratio_diff = float('inf')
+    best_ratio = (1, 1)
+    area = width * height
+    for ratio in target_ratios:
+        target_aspect_ratio = ratio[0] / ratio[1]
+        ratio_diff = abs(aspect_ratio - target_aspect_ratio)
+        if ratio_diff < best_ratio_diff:
+            best_ratio_diff = ratio_diff
+            best_ratio = ratio
+        elif ratio_diff == best_ratio_diff:
+            if area > 0.5 * image_size * image_size * ratio[0] * ratio[1]:
+                best_ratio = ratio
+    return best_ratio
+
+def dynamic_preprocess(image, min_num=1, max_num=12, image_size=448, use_thumbnail=False):
+    orig_width, orig_height = image.size
+    aspect_ratio = orig_width / orig_height
+
+    # calculate the existing image aspect ratio
+    target_ratios = set(
+        (i, j) for n in range(min_num, max_num + 1) for i in range(1, n + 1) for j in range(1, n + 1) if
+        i * j <= max_num and i * j >= min_num)
+    target_ratios = sorted(target_ratios, key=lambda x: x[0] * x[1])
+
+    # find the closest aspect ratio to the target
+    target_aspect_ratio = find_closest_aspect_ratio(
+        aspect_ratio, target_ratios, orig_width, orig_height, image_size)
+
+    # calculate the target width and height
+    target_width = image_size * target_aspect_ratio[0]
+    target_height = image_size * target_aspect_ratio[1]
+    blocks = target_aspect_ratio[0] * target_aspect_ratio[1]
+
+    # resize the image
+    resized_img = image.resize((target_width, target_height))
+    processed_images = []
+    for i in range(blocks):
+        box = (
+            (i % (target_width // image_size)) * image_size,
+            (i // (target_width // image_size)) * image_size,
+            ((i % (target_width // image_size)) + 1) * image_size,
+            ((i // (target_width // image_size)) + 1) * image_size
+        )
+        # split the image
+        split_img = resized_img.crop(box)
+        processed_images.append(split_img)
+    assert len(processed_images) == blocks
+    if use_thumbnail and len(processed_images) != 1:
+        thumbnail_img = image.resize((image_size, image_size))
+        processed_images.append(thumbnail_img)
+    return processed_images
+
+def load_image(image_file, input_size=448, max_num=12):
+    image = Image.open(image_file).convert('RGB')
+    transform = build_transform(input_size=input_size)
+    images = dynamic_preprocess(image, image_size=input_size, use_thumbnail=True, max_num=max_num)
+    pixel_values = [transform(image) for image in images]
+    pixel_values = torch.stack(pixel_values)
+    return pixel_values
+
+path = 'jcwang0602/MLLMSeg_InternVL2_5_8B_RES' # or 'jcwang0602/MLLMSeg_InternVL2_5_8B_GRES'
+model = AutoModel.from_pretrained(
+    path,
+    torch_dtype=torch.bfloat16,
+    low_cpu_mem_usage=True,
+    trust_remote_code=True).eval().cuda()
+tokenizer = AutoTokenizer.from_pretrained(path, trust_remote_code=True, use_fast=False)
+
+# Example image. You need to download an example image, e.g., from the GitHub repo's assets:
+# https://raw.githubusercontent.com/jcwang0602/MLLMSeg/main/examples/images/web_dfacd48d-d2c2-492f-b94c-41e6a34ea99f.png
+# Save it to a local path like 'examples/images/web_dfacd48d-d2c2-492f-b94c-41e6a34ea99f.png'
+# For demonstration, you might need to create dummy directories or replace the path.
+image_path = './examples/images/web_dfacd48d-d2c2-492f-b94c-41e6a34ea99f.png'
+if not os.path.exists(image_path):
+    print(f"Warning: Image not found at {image_path}. Please download it from the GitHub repo.")
+    # Fallback for demonstration if image is not present
+    dummy_image_data = np.zeros((1024, 768, 3), dtype=np.uint8)
+    dummy_image = Image.fromarray(dummy_image_data)
+    pixel_values = build_transform(input_size=448)(dummy_image).unsqueeze(0).to(torch.bfloat16).cuda()
+else:
+    pixel_values = load_image(image_path, max_num=6).to(torch.bfloat16).cuda()
+
+generation_config = dict(max_new_tokens=1024, do_sample=True)
+
+question = "In the screenshot of this web page, please give me the coordinates of the element I want to click on according to my instructions(with point).\
+\\\"'Champions League' link\\\""
+response, history = model.chat(tokenizer, pixel_values, question, generation_config, history=None, return_history=True)
+print(f'User: {question}
+Assistant: {response}')
+```
+
+---
+
+## Performance Metrics
+
+### Referring Expression Segmentation
+<img src="https://raw.githubusercontent.com/jcwang0602/MLLMSeg/main/assets/tab_res.png" width="800">
+
+### Referring Expression Comprehension
+<img src="https://raw.githubusercontent.com/jcwang0602/MLLMSeg/main/assets/tab_rec.png" width="800">
+
+### Generalized Referring Expression Segmentation
+<img src="https://raw.githubusercontent.com/jcwang0602/MLLMSeg/main/assets/tab_gres.png" width="800">
+
+---
+
+## Visualization
+### Referring Expression Segmentation
+<img src="https://raw.githubusercontent.com/jcwang0602/MLLMSeg/main/assets/res.png" width="800">
+
+### Referring Expression Comprehension
+<img src="https://raw.githubusercontent.com/jcwang0602/MLLMSeg/main/assets/rec.png" width="800">
+
+### Generalized Referring Expression Segmentation
+<img src="https://raw.githubusercontent.com/jcwang0602/MLLMSeg/main/assets/gres.png" width="800">
+
+---
+
+## Citation
+If our work is useful for your research, please consider citing:
+```bibtex
+@misc{wang2025unlockingpotentialmllmsreferring,
+      title={Unlocking the Potential of MLLMs in Referring Expression Segmentation via a Light-weight Mask Decoder}, 
+      author={Jingchao Wang and Zhijian Wu and Dingjiang Huang and Yefeng Zheng and Hong Wang},
+      year={2025},
+      eprint={2508.04107},
+      archivePrefix={arXiv},
+      primaryClass={cs.CV},
+      url={https://arxiv.org/abs/2508.04107}, 
+}
+```