metadata

license: mit
base_model:
  - fancyfeast/llama-joycaption-alpha-two-hf-llava
language:
  - en
pipeline_tag: image-text-to-text
tags:
  - captioning
  - llava

Llama Joycaption Alpha Two hf Llava FP8 Dynamic

An FP8 compression of the Llama JoyCaption Alpha Two model made by fancyfeast, using llm-compressor and compatible with vllm.

The model has been tested personally, unfortunately without the proper method, but it works well with my usage pattern.

All credit to fancyfeast and on the official model page you can see more details.

How to Get Started with the Model:

The same as the Llama JoyCaption Alpha Two:

You need the compressed-tensors lib to run the code below with FP8.

import torch
from PIL import Image
from transformers import AutoProcessor, LlavaForConditionalGeneration


IMAGE_PATH = "image.jpg"
PROMPT = "Write a long descriptive caption for this image in a formal tone."
MODEL_NAME = "JKCHSTR/llama-joycaption-alpha-two-hf-llava-FP8-Dynamic"


# Load JoyCaption
# bfloat16 is the native dtype of the LLM used in JoyCaption (Llama 3.1)
# device_map=0 loads the model into the first GPU
processor = AutoProcessor.from_pretrained(MODEL_NAME)
llava_model = LlavaForConditionalGeneration.from_pretrained(MODEL_NAME, torch_dtype="bfloat16", device_map=0)
llava_model.eval()

with torch.no_grad():
    # Load image
    image = Image.open(IMAGE_PATH)

    # Build the conversation
    convo = [
        {
            "role": "system",
            "content": "You are a helpful image captioner.",
        },
        {
            "role": "user",
            "content": PROMPT,
        },
    ]

    # Format the conversation
    # WARNING: HF's handling of chat's on Llava models is very fragile.  This specific combination of processor.apply_chat_template(), and processor() works
    # but if using other combinations always inspect the final input_ids to ensure they are correct.  Often times you will end up with multiple <bos> tokens
    # if not careful, which can make the model perform poorly.
    convo_string = processor.apply_chat_template(convo, tokenize = False, add_generation_prompt = True)
    assert isinstance(convo_string, str)

    # Process the inputs
    inputs = processor(text=[convo_string], images=[image], return_tensors="pt").to('cuda')
    inputs['pixel_values'] = inputs['pixel_values'].to(torch.bfloat16)

    # Generate the captions
    generate_ids = llava_model.generate(
        **inputs,
        max_new_tokens=300,
        do_sample=True,
        suppress_tokens=None,
        use_cache=True,
        temperature=0.6,
        top_k=None,
        top_p=0.9,
    )[0]

    # Trim off the prompt
    generate_ids = generate_ids[inputs['input_ids'].shape[1]:]

    # Decode the caption
    caption = processor.tokenizer.decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)
    caption = caption.strip()
    print(caption)