Token Embed¶
Source https://github.com/vllm-project/vllm/tree/main/examples/pooling/token_embed.
Colqwen3 Token Embed Online¶
# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
# ruff: noqa: E501
"""
Example online usage of Pooling API for ColQwen3 multi-vector retrieval.
ColQwen3 is a multi-modal late interaction model based on Qwen3-VL that
produces per-token embeddings (320-dim, L2-normalized) for both text and
image inputs. Similarity is computed via MaxSim scoring.
This example mirrors the official TomoroAI inference code
(https://huggingface.co/TomoroAI/tomoro-colqwen3-embed-4b) but uses the
vLLM serving API instead of local HuggingFace model loading.
Start the server with:
vllm serve TomoroAI/tomoro-colqwen3-embed-4b --max-model-len 4096
Then run this script:
python colqwen3_token_embed_online.py
"""
import argparse
import base64
from io import BytesIO
import numpy as np
import requests
from PIL import Image
# ── Helpers ─────────────────────────────────────────────────
def post_http_request(payload: dict, api_url: str) -> requests.Response:
headers = {"User-Agent": "Test Client"}
return requests.post(api_url, headers=headers, json=payload)
def load_image(url: str) -> Image.Image:
"""Download an image from URL (handles Wikimedia 403)."""
for hdrs in ({}, {"User-Agent": "Mozilla/5.0 (compatible; ColQwen3-demo/1.0)"}):
resp = requests.get(url, headers=hdrs, timeout=10)
if resp.status_code == 403:
continue
resp.raise_for_status()
return Image.open(BytesIO(resp.content)).convert("RGB")
raise RuntimeError(f"Could not fetch image from {url}")
def encode_image_base64(image: Image.Image) -> str:
"""Encode a PIL image to a base64 data URI."""
buf = BytesIO()
image.save(buf, format="PNG")
return "data:image/png;base64," + base64.b64encode(buf.getvalue()).decode()
def compute_maxsim(q_emb: np.ndarray, d_emb: np.ndarray) -> float:
"""Compute ColBERT-style MaxSim score between query and document."""
sim = q_emb @ d_emb.T
return float(sim.max(axis=-1).sum())
# ── Encode functions ────────────────────────────────────────
def encode_queries(texts: list[str], model: str, api_url: str) -> list[np.ndarray]:
"""Encode text queries → list of multi-vector embeddings."""
resp = post_http_request({"model": model, "input": texts}, api_url)
return [np.array(item["data"]) for item in resp.json()["data"]]
def encode_images(image_urls: list[str], model: str, api_url: str) -> list[np.ndarray]:
"""Encode image documents → list of multi-vector embeddings.
Images are sent via the chat-style `messages` field so that the
vLLM multimodal processor handles them correctly.
"""
embeddings = []
for url in image_urls:
print(f" Loading: {url.split('/')[-1]}...")
image = load_image(url)
image_uri = encode_image_base64(image)
resp = post_http_request(
{
"model": model,
"messages": [
{
"role": "user",
"content": [
{"type": "image_url", "image_url": {"url": image_uri}},
{"type": "text", "text": "Describe the image."},
],
}
],
},
api_url,
)
result = resp.json()
if resp.status_code != 200 or "data" not in result:
print(f" Error ({resp.status_code}): {str(result)[:200]}")
continue
embeddings.append(np.array(result["data"][0]["data"]))
return embeddings
# ── Main ────────────────────────────────────────────────────
def parse_args():
parser = argparse.ArgumentParser()
parser.add_argument("--host", type=str, default="localhost")
parser.add_argument("--port", type=int, default=8000)
parser.add_argument(
"--model",
type=str,
default="TomoroAI/tomoro-colqwen3-embed-4b",
)
return parser.parse_args()
def main(args):
pooling_url = f"http://{args.host}:{args.port}/pooling"
score_url = f"http://{args.host}:{args.port}/score"
model = args.model
# Same sample data as the official TomoroAI example
queries = [
"Retrieve the city of Singapore",
"Retrieve the city of Beijing",
"Retrieve the city of London",
]
image_urls = [
"https://upload.wikimedia.org/wikipedia/commons/2/27/Singapore_skyline_2022.jpg",
"https://upload.wikimedia.org/wikipedia/commons/6/61/Beijing_skyline_at_night.JPG",
"https://upload.wikimedia.org/wikipedia/commons/4/49/London_skyline.jpg",
]
# ── 1) Text query embeddings ────────────────────────────
print("=" * 60)
print("1. Encode text queries (multi-vector)")
print("=" * 60)
query_embeddings = encode_queries(queries, model, pooling_url)
for i, emb in enumerate(query_embeddings):
norm = float(np.linalg.norm(emb[0]))
print(f' Query {i}: {emb.shape} (L2 norm: {norm:.4f}) "{queries[i]}"')
# ── 2) Image document embeddings ────────────────────────
print()
print("=" * 60)
print("2. Encode image documents (multi-vector)")
print("=" * 60)
doc_embeddings = encode_images(image_urls, model, pooling_url)
for i, emb in enumerate(doc_embeddings):
print(f" Doc {i}: {emb.shape} {image_urls[i].split('/')[-1]}")
# ── 3) Cross-modal MaxSim scoring ───────────────────────
if doc_embeddings:
print()
print("=" * 60)
print("3. Cross-modal MaxSim scores (text queries × image docs)")
print("=" * 60)
# Header
print(f"{'':>35s}", end="")
for j in range(len(doc_embeddings)):
print(f" Doc {j:>2d}", end="")
print()
# Score matrix
for i, q_emb in enumerate(query_embeddings):
print(f" {queries[i]:<33s}", end="")
for j, d_emb in enumerate(doc_embeddings):
score = compute_maxsim(q_emb, d_emb)
print(f" {score:6.2f}", end="")
print()
# ── 4) Text-only /score endpoint ────────────────────────
print()
print("=" * 60)
print("4. Text-only late interaction scoring (/score endpoint)")
print("=" * 60)
text_query = "What is the capital of France?"
text_docs = [
"The capital of France is Paris.",
"Berlin is the capital of Germany.",
"Python is a programming language.",
]
resp = post_http_request(
{"model": model, "text_1": text_query, "text_2": text_docs},
score_url,
)
print(f' Query: "{text_query}"\n')
for item in resp.json()["data"]:
idx = item["index"]
print(f" Doc {idx} (score={item['score']:.4f}): {text_docs[idx]}")
if __name__ == "__main__":
args = parse_args()
main(args)
Jina Embeddings V4 Offline¶
# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
import torch
from vllm import LLM
from vllm.inputs.data import TextPrompt
from vllm.multimodal.utils import fetch_image
# Initialize model
model = LLM(
model="jinaai/jina-embeddings-v4-vllm-text-matching",
runner="pooling",
max_model_len=1024,
gpu_memory_utilization=0.8,
)
# Create text prompts
text1 = "Ein wunderschöner Sonnenuntergang am Strand"
text1_prompt = TextPrompt(prompt=f"Query: {text1}")
text2 = "浜辺に沈む美しい夕日"
text2_prompt = TextPrompt(prompt=f"Query: {text2}")
# Create image prompt
image = fetch_image(
"https://vllm-public-assets.s3.us-west-2.amazonaws.com/multimodal_asset/eskimo.jpg" # noqa: E501
)
image_prompt = TextPrompt(
prompt="<|im_start|>user\n<|vision_start|><|image_pad|><|vision_end|>Describe the image.<|im_end|>\n", # noqa: E501
multi_modal_data={"image": image},
)
# Encode all prompts
prompts = [text1_prompt, text2_prompt, image_prompt]
outputs = model.encode(prompts, pooling_task="token_embed")
def get_embeddings(outputs):
VISION_START_TOKEN_ID, VISION_END_TOKEN_ID = 151652, 151653
embeddings = []
for output in outputs:
if VISION_START_TOKEN_ID in output.prompt_token_ids:
# Gather only vision tokens
img_start_pos = torch.where(
torch.tensor(output.prompt_token_ids) == VISION_START_TOKEN_ID
)[0][0]
img_end_pos = torch.where(
torch.tensor(output.prompt_token_ids) == VISION_END_TOKEN_ID
)[0][0]
embeddings_tensor = output.outputs.data.detach().clone()[
img_start_pos : img_end_pos + 1
]
else:
# Use all tokens for text-only prompts
embeddings_tensor = output.outputs.data.detach().clone()
# Pool and normalize embeddings
pooled_output = (
embeddings_tensor.sum(dim=0, dtype=torch.float32)
/ embeddings_tensor.shape[0]
)
embeddings.append(torch.nn.functional.normalize(pooled_output, dim=-1))
return embeddings
embeddings = get_embeddings(outputs)
for embedding in embeddings:
print(embedding.shape)
Multi Vector Retrieval Offline¶
# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
from argparse import Namespace
from vllm import LLM, EngineArgs
from vllm.utils.argparse_utils import FlexibleArgumentParser
def parse_args():
parser = FlexibleArgumentParser()
parser = EngineArgs.add_cli_args(parser)
# Set example specific arguments
parser.set_defaults(
model="BAAI/bge-m3",
runner="pooling",
enforce_eager=True,
)
return parser.parse_args()
def main(args: Namespace):
# Sample prompts.
prompts = [
"Hello, my name is",
"The president of the United States is",
"The capital of France is",
"The future of AI is",
]
# Create an LLM.
# You should pass runner="pooling" for embedding models
llm = LLM(**vars(args))
# Generate embedding. The output is a list of EmbeddingRequestOutputs.
outputs = llm.embed(prompts)
# Print the outputs.
print("\nGenerated Outputs:\n" + "-" * 60)
for prompt, output in zip(prompts, outputs):
embeds = output.outputs.embedding
print(len(embeds))
# Generate embedding for each token. The output is a list of PoolingRequestOutput.
outputs = llm.encode(prompts, pooling_task="token_embed")
# Print the outputs.
print("\nGenerated Outputs:\n" + "-" * 60)
for prompt, output in zip(prompts, outputs):
multi_vector = output.outputs.data
print(multi_vector.shape)
if __name__ == "__main__":
args = parse_args()
main(args)
Multi Vector Retrieval Online¶
# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
"""
Example online usage of Pooling API for multi vector retrieval.
Run `vllm serve <model> --runner pooling`
to start up the server in vLLM. e.g.
vllm serve BAAI/bge-m3
"""
import argparse
import requests
import torch
def post_http_request(prompt: dict, api_url: str) -> requests.Response:
headers = {"User-Agent": "Test Client"}
response = requests.post(api_url, headers=headers, json=prompt)
return response
def parse_args():
parser = argparse.ArgumentParser()
parser.add_argument("--host", type=str, default="localhost")
parser.add_argument("--port", type=int, default=8000)
parser.add_argument("--model", type=str, default="BAAI/bge-m3")
return parser.parse_args()
def main(args):
api_url = f"http://{args.host}:{args.port}/pooling"
model_name = args.model
prompts = [
"Hello, my name is",
"The president of the United States is",
"The capital of France is",
"The future of AI is",
]
prompt = {"model": model_name, "input": prompts}
pooling_response = post_http_request(prompt=prompt, api_url=api_url)
for output in pooling_response.json()["data"]:
multi_vector = torch.tensor(output["data"])
print(multi_vector.shape)
if __name__ == "__main__":
args = parse_args()
main(args)