# Beyond End-to-End VLMs: Leveraging Intermediate Text Representations for Superior Flowchart Understanding

arXiv: https://arxiv.org/abs/2412.16420 · HTML: https://mlsanity.com/paper/2412.16420/

## Key facts

- Cited by 11 papers in the map (data through 14 Oct 2026).
- Placed in Chart understanding and anomaly detection, one of 16 directions in Multimodal LLMs / vision-language models.
- Builds on 7 of its 16 references that are in the map.
- First posted on arXiv 21 Dec 2024.

## Placed in

- Multimodal LLMs / vision-language models / [Chart understanding and anomaly detection](https://mlsanity.com/mllm/chart-understanding-and-anomaly-detection/)

## Builds on (most cited first, 7 of 7)

- [The Llama 3 Herd of Models](https://mlsanity.com/paper/2407.21783/) (2024)
- [Qwen2-VL: Enhancing Vision-Language Model's Perception of the World at Any Resolution](https://mlsanity.com/paper/2409.12191/) (2024)
- [IconQA: A New Benchmark for Abstract Diagram Understanding and Visual Language Reasoning](https://mlsanity.com/paper/2110.13214/) (2021)
- [FlowVQA: Mapping Multimodal Logic in Visual Question Answering with Flowcharts](https://mlsanity.com/paper/2406.19237/) (2024)
- [FlowLearn: Evaluating Large Vision-Language Models on Flowchart Understanding](https://mlsanity.com/paper/2407.05183/) (2024)
- [Exploring Question Decomposition for Zero-Shot VQA](https://mlsanity.com/paper/2310.17050/) (2023)
- [Disentangling Knowledge-based and Visual Reasoning by Question Decomposition in KB-VQA](https://mlsanity.com/paper/2406.18839/) (2024)

## Built on by (most cited first, 11 of 11)

- [Survey of GenAI for Automotive Software Development: From Requirements to Executable Code](https://mlsanity.com/paper/2507.15025/) (2025)
- [Follow the Flow: Fine-grained Flowchart Attribution with Neurosymbolic Agents](https://mlsanity.com/paper/2506.01344/) (2025)
- [Flowchart2Mermaid: A Vision-Language Model Powered System for Converting Flowcharts into Editable Diagram Code](https://mlsanity.com/paper/2512.02170/) (2025)
- [Overcoming Vision Language Model Challenges in Diagram Understanding: A Proof-of-Concept with XML-Driven Large Language Models Solutions](https://mlsanity.com/paper/2502.04389/) (2025)
- [Measuring Visual Understanding in Telecom domain: Performance Metrics for Image-to-UML conversion using VLMs](https://mlsanity.com/paper/2509.11667/) (2025)
- [Multimodal Information Fusion for Chart Understanding: A Survey of MLLMs -- Evolution, Limitations, and Cognitive Enhancement](https://mlsanity.com/paper/2602.10138/) (2026)
- [An Online Reference-Free Evaluation Framework for Flowchart Image-to-Code Generation](https://mlsanity.com/paper/2602.13376/) (2026)
- [FloCA: Towards Faithful and Logically Consistent Flowchart Reasoning](https://mlsanity.com/paper/2602.14035/) (2026)
- [Pseudo Contrastive Learning for Diagram Comprehension in Multimodal Models](https://mlsanity.com/paper/2602.23589/) (2026)
- [PathWISE: Multi-Agent Cancer Pathway Triaging Ontology Learning from Clinical Flowcharts](https://mlsanity.com/paper/2605.25970/) (2026)
- [Knossos and Ariadne: Benchmarking and Learning Complete Diagram Topology Extraction with Vision-Language Models](https://mlsanity.com/paper/2610.04721/) (2026)

## Abstract (arXiv)

Flowcharts are typically presented as images, driving the trend of using vision-language models (VLMs) for end-to-end flowchart understanding. However, two key challenges arise: (i) Limited controllability--users have minimal influence over the downstream task, as they can only modify input images, while the training of VLMs is often out of reach for most researchers. (ii) Lack of explainability--it is difficult to trace VLM errors to specific causes, such as failures in visual encoding or reasoning. We propose TextFlow, addressing aforementioned issues with two stages: (i) Vision Textualizer--which generates textual representations from flowchart images; and (ii) Textual Reasoner--which performs question-answering based on the text representations. TextFlow offers three key advantages: (i) users can select the type of text representations (e.g., Graphviz, Mermaid, PlantUML), or further convert them into executable graph object to call tools, enhancing performance and controllability; (ii) it improves explainability by helping to attribute errors more clearly to visual or textual processing components; and (iii) it promotes the modularization of the solution, such as allowing advanced LLMs to be used in the Reasoner stage when VLMs underperform in end-to-end fashion. Experiments on the FlowVQA and FlowLearn benchmarks demonstrate TextFlow's state-of-the-art performance as well as its robustness. All code is publicly available.
