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Llava

大型語言與視覺助手。支持視覺指令微調及基於圖像的對話。將 CLIP 視覺編碼器與 Vicuna/LLaMA 語言模型相結合。支持多輪圖像聊天、視覺問答和指令遵循。適用於視覺語言聊天機器人或圖像理解任務。最適合用於對話式圖像分析。

技能元數據

來源可選 — 使用 hermes skills install official/mlops/llava 安裝
路徑optional-skills/mlops/llava
版本1.0.0
作者Orchestra Research
許可證MIT
依賴項transformers, torch, pillow
標籤LLaVA, Vision-Language, Multimodal, Visual Question Answering, Image Chat, CLIP, Vicuna, Conversational AI, Instruction Tuning, VQA

參考:完整 SKILL.md

信息

以下是 Hermes 在觸發此技能時加載的完整技能定義。這是技能激活時代理所看到的指令。

LLaVA - 大型語言與視覺助手

用於對話式圖像理解的開源視覺語言模型。

何時使用 LLaVA

適用場景:

  • 構建視覺語言聊天機器人
  • 視覺問答 (VQA)
  • 圖像描述和字幕生成
  • 多輪圖像對話
  • 視覺指令遵循
  • 帶圖像的文檔理解

指標

  • GitHub 星標超過 23,000+
  • 達到 GPT-4V 級別的能力(目標)
  • Apache 2.0 許可證
  • 多種模型尺寸(7B-34B 參數)

改用替代方案

  • GPT-4V:最高質量,基於 API
  • CLIP:簡單的零樣本分類
  • BLIP-2:僅適用於字幕生成時效果更好
  • Flamingo:研究用途,非開源

快速開始

安裝

# Clone repository
git clone https://github.com/haotian-liu/LLaVA
cd LLaVA

# Install
pip install -e .

基本用法

from llava.model.builder import load_pretrained_model
from llava.mm_utils import get_model_name_from_path, process_images, tokenizer_image_token
from llava.constants import IMAGE_TOKEN_INDEX, DEFAULT_IMAGE_TOKEN
from llava.conversation import conv_templates
from PIL import Image
import torch

# Load model
model_path = "liuhaotian/llava-v1.5-7b"
tokenizer, model, image_processor, context_len = load_pretrained_model(
model_path=model_path,
model_base=None,
model_name=get_model_name_from_path(model_path)
)

# Load image
image = Image.open("image.jpg")
image_tensor = process_images([image], image_processor, model.config)
image_tensor = image_tensor.to(model.device, dtype=torch.float16)

# Create conversation
conv = conv_templates["llava_v1"].copy()
conv.append_message(conv.roles[0], DEFAULT_IMAGE_TOKEN + "\nWhat is in this image?")
conv.append_message(conv.roles[1], None)
prompt = conv.get_prompt()

# Generate response
input_ids = tokenizer_image_token(prompt, tokenizer, IMAGE_TOKEN_INDEX, return_tensors='pt').unsqueeze(0).to(model.device)

with torch.inference_mode():
output_ids = model.generate(
input_ids,
images=image_tensor,
do_sample=True,
temperature=0.2,
max_new_tokens=512
)

response = tokenizer.decode(output_ids[0], skip_special_tokens=True).strip()
print(response)

可用模型

模型參數量顯存 (VRAM)質量
LLaVA-v1.5-7B7B~14 GB良好
LLaVA-v1.5-13B13B~28 GB更好
LLaVA-v1.6-34B34B~70 GB最佳
# Load different models
model_7b = "liuhaotian/llava-v1.5-7b"
model_13b = "liuhaotian/llava-v1.5-13b"
model_34b = "liuhaotian/llava-v1.6-34b"

# 4-bit quantization for lower VRAM
load_4bit = True # Reduces VRAM by ~4×

CLI 用法

# Single image query
python -m llava.serve.cli \
--model-path liuhaotian/llava-v1.5-7b \
--image-file image.jpg \
--query "What is in this image?"

# Multi-turn conversation
python -m llava.serve.cli \
--model-path liuhaotian/llava-v1.5-7b \
--image-file image.jpg
# Then type questions interactively

Web UI (Gradio)

# Launch Gradio interface
python -m llava.serve.gradio_web_server \
--model-path liuhaotian/llava-v1.5-7b \
--load-4bit # Optional: reduce VRAM

# Access at http://localhost:7860

多輪對話

# Initialize conversation
conv = conv_templates["llava_v1"].copy()

# Turn 1
conv.append_message(conv.roles[0], DEFAULT_IMAGE_TOKEN + "\nWhat is in this image?")
conv.append_message(conv.roles[1], None)
response1 = generate(conv, model, image) # "A dog playing in a park"

# Turn 2
conv.messages[-1][1] = response1 # Add previous response
conv.append_message(conv.roles[0], "What breed is the dog?")
conv.append_message(conv.roles[1], None)
response2 = generate(conv, model, image) # "Golden Retriever"

# Turn 3
conv.messages[-1][1] = response2
conv.append_message(conv.roles[0], "What time of day is it?")
conv.append_message(conv.roles[1], None)
response3 = generate(conv, model, image)

常見任務

圖像字幕生成

question = "Describe this image in detail."
response = ask(model, image, question)

視覺問答

question = "How many people are in the image?"
response = ask(model, image, question)

對象檢測(文本形式)

question = "List all the objects you can see in this image."
response = ask(model, image, question)

場景理解

question = "What is happening in this scene?"
response = ask(model, image, question)

文檔理解

question = "What is the main topic of this document?"
response = ask(model, document_image, question)

訓練自定義模型

# Stage 1: Feature alignment (558K image-caption pairs)
bash scripts/v1_5/pretrain.sh

# Stage 2: Visual instruction tuning (150K instruction data)
bash scripts/v1_5/finetune.sh

量化(減少顯存佔用)

# 4-bit quantization
tokenizer, model, image_processor, context_len = load_pretrained_model(
model_path="liuhaotian/llava-v1.5-13b",
model_base=None,
model_name=get_model_name_from_path("liuhaotian/llava-v1.5-13b"),
load_4bit=True # Reduces VRAM ~4×
)

# 8-bit quantization
load_8bit=True # Reduces VRAM ~2×

最佳實踐

  1. 從 7B 模型開始 - 質量良好,顯存佔用可控
  2. 使用 4-bit 量化 - 顯著減少顯存佔用
  3. 需要 GPU - CPU 推理極其緩慢
  4. 清晰的提示詞 - 具體的問題能獲得更好的回答
  5. 多輪對話 - 保持對話上下文
  6. Temperature 0.2-0.7 - 平衡創造性與一致性
  7. max_new_tokens 512-1024 - 用於生成詳細回覆
  8. 批處理 - 按順序處理多張圖像

性能

模型顯存 (FP16)顯存 (4-bit)速度 (tokens/s)
7B~14 GB~4 GB~20
13B~28 GB~8 GB~12
34B~70 GB~18 GB~5

在 A100 GPU 上

基準測試

LLaVA 在以下基準測試中取得了具有競爭力的分數:

  • VQAv2: 78.5%
  • GQA: 62.0%
  • MM-Vet: 35.4%
  • MMBench: 64.3%

侷限性

  1. 幻覺 - 可能會描述圖像中不存在的內容
  2. 空間推理 - 難以精確判斷位置
  3. 小文本 - 難以閱讀細小文字
  4. 對象計數 - 對於大量對象的計數不精確
  5. 顯存要求 - 需要高性能 GPU
  6. 推理速度 - 比 CLIP 慢

與框架集成

LangChain

from langchain.llms.base import LLM

class LLaVALLM(LLM):
def _call(self, prompt, stop=None):
# Custom LLaVA inference
return response

llm = LLaVALLM()

Gradio 應用

import gradio as gr

def chat(image, text, history):
response = ask_llava(model, image, text)
return response

demo = gr.ChatInterface(
chat,
additional_inputs=[gr.Image(type="pil")],
title="LLaVA Chat"
)
demo.launch()

資源