PositionOCR: Augmenting Positional Awareness in Multi-Modal Models via Hybrid Specialist Integration
Abstract
In recent years, Multi-modal Large Language Models (MLLMs) have achieved strong performance in OCR-centric Visual Question Answering (VQA) tasks, illustrating their capability to process heterogeneous data and exhibit adaptability across varied contexts. However, these MLLMs rely on a Large Language Model (LLM) as the decoder, which is primarily designed for linguistic processing, and thus inherently lacks the positional reasoning required for precise visual tasks, such as text spotting and text grounding. Additionally, the extensive parameters of MLLMs necessitate substantial computational resources and large-scale data for effective training. Conversely, text spotting specialists achieve state-of-the-art coordinate predictions but lack semantic reasoning capabilities. This dichotomy motivates our key research question: Can we synergize the efficiency of specialists with the contextual power of LLMs to create a positionally-accurate MLLM? To overcome these challenges, we introduce PositionOCR, a parameter-efficient hybrid architecture that seamlessly integrates a text spotting model's positional strengths with an LLM's contextual reasoning. Comprising 131M trainable parameters, this framework demonstrates outstanding multi-modal processing capabilities, particularly excelling in tasks such as text grounding and text spotting, consistently surpassing traditional MLLMs.
Figures & tables
| Task | Samples | Datasets |
| Document | 1344.5k | IIT-CDIP Lewis et al. (2006) , DocVQA Mathew et al. (2021) , InfoVQA Mathew et al. (2022) |
| Chart | 18.3k | ChartQA Masry et al. (2022) |
| Scene text | 387.1k | Total-Text Ch’ng and Chan (2017) , TextOCR Singh et al. (2021) , ICDAR13 Karatzas et al. (2013) , ICDAR15 Karatzas et al. (2015) |
| ICDAR2017 MLT Nayef et al. (2017) , HierText Long et al. (2022) , OpenVINO Krylov et al. (2021) | ||
| SCUT-CTW1500 Yuliang et al. (2017) , Curve Synthetic Dataset Liu et al. (2020) | ||
| Obj. detection | 334.3k | COCO Lin et al. (2015) , Objects365 Shao et al. (2019) |
| Domain | Samples | Datasets |
| Document | 4758.8k | DocGenome Xia et al. (2024) , DocVQA Mathew et al. (2021) , InfoVQA Mathew et al. (2022) , KLC Stanisławek et al. (2021) |
| VisualMRC Tanaka et al. (2021) , DocReason25k Hu et al. (2024) , Sujet-Finance AI (2025) , | ||
| POIE Kuang et al. (2023) , SROIE Huang et al. (2019) , FUNSD Jaume et al. (2019) , TextCaps Sidorov et al. (2020) , | ||
| SynthDoG-en Kim et al. (2022) , Docmatix Laurençon et al. (2024) , OCR-VQA Mishra et al. (2019) | ||
| Table | 270.9k | WikiTableQuestions Pasupat and Liang (2015) , TabMWP Lu et al. (2023) , DeepForm Svetlichnaya (2020) , |
| TableFact Chen et al. (2019) ,TableBench Wu et al. (2024) , TableVQA Kim et al. (2024) |
| Methods | TP | Text Grounding | ||||
|---|---|---|---|---|---|---|
| Block | Line | Phrase | Word | All | ||
| Qwen2.5-VL Bai et al. (2025) | 7B | 0.3 | 32.2 | 6.2 | 20.6 | 15.0 |
| DocOwl-1.5 Liu et al. (2024c) | 8.1B | 91.3 | 85.9 | 76.4 | 70.4 | 80.4 |
| DOGE Zhou et al. (2024) | 8B | 95.4 | 84.1 | 78.4 | 74.7 | 82.6 |
| PositionOCR | 131M | 76.5 | 89.1 | 81.9 | 84.0 | 83.0 |
| Methods | Trainable Params | Accuracy @ IoU=0.5 |
|---|---|---|
| Qwen2.5-VL Bai et al. (2025) | 7B | 79.92% |
| PositionOCR | 131M | 80.31% |
| Methods | TP | Total-Text | ICDAR2015 | |||
|---|---|---|---|---|---|---|
| None | Full | S | W | G | ||
| Qwen2.5-VL Bai et al. (2025) | 7B | 45.2 | 51.1 | 46.4 | 43.7 | 42.3 |
| TextMonkey Liu et al. (2024c) | 9.7B | 61.4 | - | - | - | 45.1 |
| PositionOCR | 131M | 66.6 | 77.4 | 74.1 | 71.1 | 67.7 |
| Methods | TP | DocVQA | DeepForm | ChartQA | TabFact | SROIE | POIE |
|---|---|---|---|---|---|---|---|
| Dessurt Davis et al. (2022) | 127M | 63.2 | - | - | - | - | - |
| Donut Kim et al. (2022) | 176M | 67.5 | 61.6 | 41.8 | 54.6 | - | - |
| DocPeida Feng et al. (2023) | 7.1B | 47.1 | - | 46.9 | - | 21.4 | 39.9 |
| DocOwl Ye et al. (2023a) | 7.3B | 62.2 | 42.6 | 57.4 | 67.6 | 1.7 | 2.5 |
| UReader Ye et al. (2023b) | 7.1B | 65.4 | 49.5 | 59.3 | 67.6 | - | - |
| QwenVL Bai et al. (2023) | 9.6B | 65.1 | 65.7 | - | - | - |
| Methods | Refclef | Refcoco | Refcoco+ | Refcocog | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Test | Val | TestA | TestB | Val | TestA | TestB | Val | Test | Val | |
| CITE Plummer et al. (2018) | 34.13 | - | - | - | - | - | - | - | - | - |
| MMI Mao et al. (2016) | - | - | 64.9 | 54.5 | - | 54.0 | 42.8 | - | - | - |
| Speaker Yu et al. (2017) | - | - | 67.6 | 55.1 | - | 55.8 | 43.4 | - | - | - |
| PFOS Sun et al. (2022) | 67.9 | - | 81.4 | 73.1 | 78.4 | 72.4 | 55.2 | 65.8 | 67.6 | 67.8 |
| OFA-L* Wang et al. (2022) | - | - | 83.6 | 76.3 | 79.9 | 76.0 | 61.7 | 68.2 | 67.5 | 67.5 |
| Methods | Total-Text | ICDAR2015 | |||
|---|---|---|---|---|---|
| None | Full | S | W | G | |
| TOSS Tang et al. (2022) | 65.1 | 74.8 | 65.9 | 59.6 | 52.4 |
| SPTS Peng et al. (2022) | 74.2 | 82.4 | 77.5 | 70.2 | 65.8 |
| SPTS-v2 Liu et al. (2023) | 75.5 | 84.0 | 82.3 | 77.7 | 72.6 |
| InstructOCR Duan et al. (2024b) | 77.1 | 84.1 | 82.5 | 77.1 | 72.1 |
| PositionOCR | 76.6 | 83.4 | 80.5 | 78.2 | 74.5 |