Multimodal RAG: Retrieval with Images, Tables, and Text — The 2026 Guide

Text-only RAG was just the beginning. In 2026, real-world documents are packed with charts, tables, diagrams, screenshots, and infographics. Standard RAG pipelines that only process text miss critical information. This guide shows you how to build multimodal RAG systems that understand the full richness of your documents.

Why Text-Only RAG Falls Short

Consider a typical enterprise PDF: it might contain financial tables, process diagrams, product screenshots, and technical drawings. A text-only RAG pipeline will:

Architecture Patterns for Multimodal RAG

1. Embed-Then-Retrieve: Embed all modalities (text, images, tables) into a shared vector space. At query time, retrieve chunks from any modality. Models like CLIP and ColPali enable this.

2. Retrieve-Then-Rerank: First retrieve candidates using cheap text embeddings, then rerank using expensive multimodal models. Best for large document collections.

3. Unified Multimodal Indexing: Parse documents into a unified representation where text, images, and tables are all indexed together. Most accurate but most complex to build.

Embedding Models for Multimodal

Model Modalities Strength
CLIP Image + Text General purpose alignment
ColPali PDF pages Page-level visual retrieval
ColNemb Multi-vector Fine-grained chunk matching
Jina CLIP v2 Multilingual 8-language support

Building a Multimodal RAG Pipeline

from colpali_engine.models import ColPali
from qdrant_client import QdrantClient
from google.generativeai import GenerativeModel

# 1. Parse documents (unstructured.io ormarker-pdf)
# 2. Create multi-vector embeddings
model = ColPali.from_pretrained("vidore/colpali-v1.2")

# 3. Index in vector DB (Qdrant with multi-vector support)
client = QdrantClient("localhost", port=6333)
collection = client.create_collection(
    "multimodal_docs",
    vectors_config={"page_vectors": {"size": 128, "distance": "Cosine"}}
)

# 4. Query: embed question, retrieve relevant pages, generate with Gemini
def query(question: str):
    q_embed = model.encode_question(question)
    results = client.search("multimodal_docs", query_vector=q_embed, limit=5)
    # Pass retrieved pages (images) to Gemini for answer generation
    model = GenerativeModel("gemini-2.0-flash")
    response = model.generate_content([question] + [r.payload["page_image"] for r in results])
    return response.text

Table Handling for RAG

Tables require special treatment in RAG systems:

Benchmarks

Benchmark Tests Top Model
DocVQA Document visual QA GPT-4o + ColPali: 82%
ChartQA Chart understanding Gemini 2.0: 78%
InfoVQA Infographic QA GPT-4o: 71%

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