TomoroAI/tomoro-colqwen3-embed-8b is a state-of-the-art ColPali-style multimodal embedding model. It maps text queries, visual documents (images, PDFs) or short videos into aligned multi-vector embeddings.
Qwen3-VL 8B (Encoder-only variant) + 320-dim Projection Head
Methodology
ColPali-style Late Interaction (MaxSim scoring)
Token Budget
Up to 1,280 visual tokens per page or 5120 visual tokens per video (text prompts constrained only by the base context window)
Context Window
32k (inherited from base), typical usage < 2k tokens
Output
Multi-vector (Seq_Len × 320), L2-normalized
Supported Modalities
Text Queries, RGB Images, Synthetic Documents, Short Video (Frame-wise)
Precision
bfloat16 weights, FlashAttention 2 enabled
Key Properties
Merged Encoders: Combines the Qwen3-VL vision encoder (patch-grid tokens with spatial merge) and language encoder.
Projection: A custom 320-dim head projects every token (text or visual) into a vector.
Processing:
Queries: Left-padded text sequences.
Documents: Rendered with a lightweight vision prompt and flattened into image tokens.
Video: Supports video retrieval by decoding videos into frames and processing via the vision stack (generalization capability, not explicitly fine-tuned; dedicated benchmark coming soon).
Tomoro ColQwen3: Stores max 1,280 tokens @ 320 dims (≈0.82 TB for 1M images).
Result:13× smaller footprint with higher performance.
📊 Evaluation Results
We report results on the ViDoRe benchmark suite. The model sets new standards on multilingual and English splits on ViDoRe V2 and V3 while maintaining comparable high performance on ViDoRe V1.
To demonstrate that Tomoro ColQwen3 strongly generalizes to video retrieval, we evaluated the models on the CareBench for text to video (General Retrieval) task and MMEB-V2 video_ret benchmark.
CareBench Evaluation
For this evaluation, we utilized a raw video encoding approach: our models encoded the video files directly without any additional textual annotations or metadata inputs. This highlights the model's ability to perform retrieval based purely on visual semantics.
IFM-TTE-7B and seed-1.6-embedding utilize video-text fine-tuning, whereas the Tomoro ColQwen series relies solely on image-text data.
💻 Usage
The processor exposes process_texts, process_images, and score_multi_vector.
Prerequisites
We strongly suggest flash-attn to be installed. If not, please change to attention_impl="sdpa"
Currently we only support torch==2.8.0, for higher pytorch version, please build flash attention manually, otherwise performance throughput could be low.
tomoro-colqwen3-embed-8b can be used as a multi-vector (ColBERT-style late interaction) retriever directly with Sentence Transformers via the MultiVectorEncoder.
pip install "sentence-transformers[image]>=6.0.0"
python
1from sentence_transformers import MultiVectorEncoder
23model = MultiVectorEncoder("TomoroAI/tomoro-colqwen3-embed-8b", trust_remote_code=True)45queries =[6"What is the variable represented on the y-axis of the graph?",7"Total outlay is maximum in which year?",8]9documents =[10f"https://huggingface.co/datasets/sentence-transformers/example-documents/resolve/main/doc{i}.jpg"11for i inrange(1,5)12]1314query_embeddings = model.encode_query(queries)15document_embeddings = model.encode_document(documents)16print(f"Query 0 shape: {tuple(query_embeddings[0].shape)}")17print(f"Document 0 shape: {tuple(document_embeddings[0].shape)}")18# Query 0 shape: (23, 320)19# Document 0 shape: (1251, 320)2021# MaxSim late-interaction scoring (rows = queries, columns = images)22scores = model.similarity(query_embeddings, document_embeddings)23print(scores)24# tensor([[12.4336, 8.5479, 6.7305, 5.1968],25# [ 4.5449, 11.1719, 4.8320, 4.5195]])
[!NOTE]
Pages are tiled adaptively, so document embeddings vary in length (1251 tokens for the first three
example pages, 1271 for the fourth). MaxSim handles that, and model.similarity masks the padding.
Using Transformers
python
1import torch
2from transformers import AutoModel, AutoProcessor
3from PIL import Image, UnidentifiedImageError
4import requests
5from io import BytesIO
67# Configuration8MODEL_ID ="TomoroAI/tomoro-colqwen3-embed-8b"9DTYPE = torch.bfloat16
10DEVICE ="cuda"if torch.cuda.is_available()else"cpu"1112# Load Model & Processor13processor = AutoProcessor.from_pretrained(14 MODEL_ID,15 trust_remote_code=True,16 max_num_visual_tokens=1280,17)18model = AutoModel.from_pretrained(19 MODEL_ID,20 dtype=DTYPE,21 attn_implementation="flash_attention_2",22 trust_remote_code=True,23 device_map=DEVICE,24).eval()2526# Sample Data27queries =[28"Retrieve the city of Singapore",29"Retrieve the city of Beijing",30"Retrieve the city of London",31]32docs =[33"https://upload.wikimedia.org/wikipedia/commons/2/27/Singapore_skyline_2022.jpg",34"https://upload.wikimedia.org/wikipedia/commons/6/61/Beijing_skyline_at_night.JPG",35"https://upload.wikimedia.org/wikipedia/commons/4/49/London_skyline.jpg",36]3738defload_image(url:str)-> Image.Image:39# Some CDNs (e.g., Wikimedia) expect a browser-like UA to avoid 403s.40for headers in({},{"User-Agent":"Mozilla/5.0 (compatible; ColQwen3-demo/1.0)"}):41 resp = requests.get(url, headers=headers, timeout=10)42if resp.status_code ==403:43continue44 resp.raise_for_status()45try:46return Image.open(BytesIO(resp.content)).convert("RGB")47except UnidentifiedImageError as e:48raise RuntimeError(f"Failed to decode image from {url}")from e
49raise RuntimeError(f"Could not fetch image (HTTP 403) from {url}; try downloading locally and loading from file path.")5051# Helper Functions52defencode_queries(texts, batch_size=8):53 outputs =[]54for start inrange(0,len(texts), batch_size):55 batch = processor.process_texts(texts=texts[start : start + batch_size])56 batch ={k: v.to(DEVICE)for k, v in batch.items()}57with torch.inference_mode():58 out = model(**batch)59 vecs = out.embeddings.to(torch.bfloat16).cpu()60 outputs.extend(vecs)61return outputs
6263defencode_docs(urls, batch_size=4):64 pil_images =[load_image(url)for url in urls]65 outputs =[]66for start inrange(0,len(pil_images), batch_size):67 batch_imgs = pil_images[start : start + batch_size]68 features = processor.process_images(images=batch_imgs)69 features ={k: v.to(DEVICE)ifisinstance(v, torch.Tensor)else v for k, v in features.items()}70with torch.inference_mode():71 out = model(**features)72 vecs = out.embeddings.to(torch.bfloat16).cpu()73 outputs.extend(vecs)74return outputs
7576# Execution77query_embeddings = encode_queries(queries)78doc_embeddings = encode_docs(docs)7980# MaxSim Scoring81scores = processor.score_multi_vector(query_embeddings, doc_embeddings)82print(scores)
🎞️ Lightweight Video Retrieval
ColQwen3 generalizes to short videos while learning from image-text retrieval task. This minimal example samples a clip with torchvision, encodes queries and frames, then pools frame embeddings with a per-dimension max before MaxSim scoring.
We recommand use of maximum 5120 visual tokens for video retrieval task for best performance.
python
1from pathlib import Path
23import torch
4from transformers import AutoModel, AutoProcessor
56MODEL_ID ="TomoroAI/tomoro-colqwen3-embed-8b"7DTYPE = torch.bfloat16
8DEVICE ="cuda"if torch.cuda.is_available()else"cpu"910processor = AutoProcessor.from_pretrained(11 MODEL_ID,12 trust_remote_code=True,13 max_num_visual_tokens=5120,14)15model = AutoModel.from_pretrained(16 MODEL_ID,17 dtype=DTYPE,18 attn_implementation="flash_attention_2",19 trust_remote_code=True,20 device_map=DEVICE,21).eval()2223queries =["Retrieve the football video","Find the basketball clip","Find the swimming clip","Find the wrestling clip"]24videos =["/root/sample_videos/football.mp4","/root/sample_videos/basketball.mp4","/root/sample_videos/swimming.mp4","/root/sample_videos/wrestling.mp4"]252627defencode_queries(texts):28 batch = processor.process_texts(texts=texts)29 batch ={k: v.to(DEVICE)for k, v in batch.items()}30with torch.inference_mode():31 out = model(**batch)32return out.embeddings.to(torch.bfloat16).cpu()3334defencode_videos(paths):35 vids =[str(Path(p).expanduser())for p in paths]36 feats = processor(37 videos=vids,38 padding="longest",39 return_tensors=None,# keep metadata as Python objects until we drop it40 videos_kwargs={"return_metadata":True},41)42 feats.pop("video_metadata",None)# drop metadata before forwarding to the model43 feats = feats.convert_to_tensors(tensor_type="pt")44 feats ={k: v.to(DEVICE)ifisinstance(v, torch.Tensor)else v for k, v in feats.items()}45with torch.inference_mode():46 out = model(**feats)47return out.embeddings.to(torch.bfloat16).cpu()4849q_emb = encode_queries(queries)50v_emb = encode_videos(videos)51scores = processor.score_multi_vector(q_emb, v_emb)52print(scores)
⚖️ Strengths & Limitations
Strengths
Performance: State of the art retrieval performance on ViDoRe V2 & V3 dataset with excellent performance on multimodal document retrieval.
Complex Layouts: Excellent handling of chart-rich PDFs, domain-specific documents.
End-to-end Retrieval: Capable of OCR-free retrieval on unseen multimodal documents without using an intermediate vision LLM to generate summary for retrieval.
Retrieval Task Transfer: Inherited strong text retrieval performance from the merged vector of the Qwen3-Embedding-8B model.
Multilingualism: Strong performance on non-English document inputs.
Limitations
Video Support: The retrieval model generalizes to video retrieval on our preliminary findings, however it's not fine-tuned on large-scale video retrieval datasets, we plan to further improve this in the future.
Storage Cost: Still larger than single‑vector baselines despite the smaller token dimension.
Retrieval Instructions: The model currently is not fine-tuned with diverse system instructions similar to Qwen3-Embedding models, we intent to improve this with more synthetic dataset in the future.
License & Data
Distributed under Apache 2.0.
Weights: Upstream Qwen checkpoints retain their community licenses; ensure compliance when mixing.
Data: Training data includes ViDoRe/MTEB corpora and synthetic VisRAG assets.
Acknowledgement
We gratefully acknowledge the support of Tomoro AI, a leading AI engineering firm dedicated to delivering high-quality enterprise solutions that accelerate complex R&D and business transformation. This work is directly applied to enhance Tomoro’s customized multimodal agentic RAG pipelines, empowering the autonomous agents to parse, reason over, and retrieve from large-scale enterprise internal documentation. By bridging the gap between vision and language, this model supports Tomoro AI's mission to accelerate the delivery of high-quality enterprise multimodal solutions and deploy robust, production-grade intelligence across high-stakes industries.
📚 Citation
If you use this model, please cite:
bibtex
1@misc{huang2025beyond,
2 author = {Huang, Xin and Tan, Kye Min},
3 title = {Beyond Text: Unlocking True Multimodal, End-to-end RAG with Tomoro ColQwen3},
4 year = {2025},
5 url = {https://tomoro.ai/insights/beyond-text-unlocking-true-multimodal-end-to-end-rag-with-tomoro-colqwen3},
6 publisher = {Tomoro.ai}
7}