JanHutter/verifierreward
075
VerifierReward Qwen3-VL 8B
import torch
from transformers import AutoProcessor, Qwen3VLForConditionalGeneration
model_id = "JanHutter/verifierreward"
processor = AutoProcessor.from_pretrained(
model_id, max_pixels=512 * 512, fix_mistral_regex=False,
)
model = Qwen3VLForConditionalGeneration.from_pretrained(
model_id,
dtype=torch.bfloat16,
device_map="auto",
attn_implementation="sdpa",
).eval()Score image-prompt alignment
The model was trained to answer yes or no. The scalar reward used during evaluation is the full-vocabulary probability of the next token being yes.
import torch
from PIL import Image
image = Image.open("image.jpg").convert("RGB")
instruction = """You are an AI assistant specializing in image analysis and ranking. Your task is to analyze and compare image based on how well they match the given prompt.
The given prompt is:{prompt}. Please consider the prompt and the image to make a decision and response directly with 'yes' or 'no'."""
messages = [{
"role": "user",
"content": [
{"type": "image", "image": image},
{"type": "text", "text": instruction.format(prompt="a red car in snow")},
],
}]
inputs = processor.apply_chat_template(
[messages],
tokenize=True,
add_generation_prompt=True,
return_dict=True,
return_tensors="pt",
).to(model.device)
with torch.inference_mode():
logits = model(**inputs, use_cache=False).logits[:, -1, :].float()
yes_ids = processor.tokenizer.encode("yes", add_special_tokens=False)
assert len(yes_ids) == 1
yes_id = yes_ids[0]
reward = torch.softmax(logits, dim=-1)[:, yes_id]
print(reward.item())