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GIR-Bench: Versatile Benchmark for Generating Images with Reasoning
Hongxiang Li, Yaowei Li, Bin Lin, Yuwei Niu, Yuhang Yang, Xiaoshuang Huang, Jiayin Cai, Xiaolong Jiang, Yao Hu, Long Chen
TL;DR
Existing benchmarks do not rigorously assess understanding–generation alignment and reasoning in complex visual tasks. GIR-Bench evaluates unified models across paired understanding and generation, reasoning-centric text-to-image generation, and multi-step editing with task-specific evaluation pipelines. The results show an advantage over generation-only models on reasoning-intensive tasks, alongside persistent difficulty transferring reasoning into faithful visual outputs.
Problem
Existing benchmarks provide limited evaluation of understanding–generation alignment and reasoning in complex visual tasks.
Source: §1 · p. 2Method
GIR-Bench evaluates understanding–generation consistency, reasoning-centric text-to-image generation, and editing with task-specific evaluation pipelines.
Source: §1 · pp. 2–3Results
Unified models consistently surpass generation-only models on reasoning-intensive tasks but still struggle to transfer reasoning into faithful visual outputs.
Source: §5 · p. 10Takeaways & Limitations
The findings point to the importance of advancing unified models that seamlessly integrate reasoning and generation.
Source: §5 · p. 10
Abstract
from arXiv · showhide
Unified multimodal models integrate the reasoning capacity of large language models with both image understanding and generation, showing great promise for advanced multimodal intelligence. However, the community still lacks a rigorous reasoning-centric benchmark to systematically evaluate the alignment between understanding and generation, and their generalization potential in complex visual tasks. To this end, we introduce GIR-Bench, a comprehensive benchmark that evaluates unified models across three complementary perspectives. Firstly, we investigate understanding-generation consistency (GIR-Bench-UGC), asking whether models can consistently leverage the same knowledge in both understanding and generation tasks. Secondly, we investigate whether models can perform reasoning-centric text-to-image generation that requires applying logical constraints and implicit knowledge to generate faithful visual content (GIR-Bench-T2I). Thirdly, we evaluate whether models can handle multi-step reasoning in editing (GIR-Bench-Edit). For each subset, we carefully design different task-specific evaluation pipelines tailored for each task. This enables fine-grained and interpretable evaluation while mitigating biases from the prevalent MLLM-as-a-Judge paradigm. Extensive ablations over various unified models and generation-only systems have shown that: Although unified models are more capable of reasoning-driven visual tasks, they still exhibit a persistent gap between understanding and generation. The data and code for GIR-Bench are available at https://github.com/HKUST-LongGroup/GIR-Bench.
1 INTRODUCTION
Existing benchmarks provide limited coverage of reasoning-centric generation and do not adequately measure understanding–generation alignment or offer interpretable evaluations. GIR-Bench evaluates unified models across understanding, generation, and editing, finding that reasoning-driven visual tasks remain challenging and that understanding still outpaces generation.
1 INTRODUCTION
- Earlier benchmarks focused mainly on object attributes and composition, while existing reasoning benchmarks remain limited in evaluation dimensions and protocols.They do not adequately capture unified models’ full capabilities.Source: §1 · p. 2
- Existing evaluations cannot quantify knowledge and reasoning transfer between understanding, generation, and editing, and often rely on MLLM judges.Such dependence couples evaluation results to multimodal models’ own biases and limitations.Source: §1 · p. 2
- Unified models show a persistent understanding–generation gap, even though integrating understanding with generation enables more complex visual tasks.The benchmark also reveals a performance gap between unified and generation-only models on reasoning-driven visual tasks.Source: §1 · p. 3
- GIR-Bench evaluates unified multimodal models across three perspectives using diverse tasks and task-specific evaluation pipelines.The pipelines are designed to provide fine-grained, interpretable metrics beyond MLLM-as-a-Judge evaluation.Source: §1 · pp. 2–3
2 GIR-BENCH
GIR-Bench combines paired understanding and generation evaluations with reasoning-centric image generation and editing tasks. Its task designs use reference images, ground truth, and task-specific evaluation procedures to assess these capabilities.
2.1 GIR-BENCH-UGC
- GIR-Bench-UGC pairs implicit prompts and reference images for 300 real-world entities to assess understanding–generation consistency.Generation is evaluated by average DINOv3 feature similarity to reference image sets; understanding uses reference images for visual question-answering cases.Source: §2.1 · p. 4, Figure 3 · p. 4
2.2 GIR-BENCH-T2I
- GIR-Bench-T2I uses 300 prompts across numerical reasoning, spatial layout, and text rendering, with deterministic tasks and verifiable ground truth.Numerical reasoning requires all detected object counts to match; spatial relations are checked using bounding boxes.Source: §2.2 · pp. 4–5
- For implicit text-rendering prompts, the word-level continuous substring score rewards ground-truth words covered by continuous character spans while allowing extra text.The score divides the number of covered ground-truth words by the number of words in the ground truth.Source: §2.2 · p. 5
2.3 GIR-BENCH-EDIT
- GIR-Bench-Edit evaluates visual puzzles, Sudoku logic, and reasoning perception using input images and corresponding ground truths.Evaluation uses normalized FID for puzzle reconstruction, digit-and-position accuracy for Sudoku, and mask IoU for reasoning perception.Source: §2.3 · pp. 5–6
3 EXPERIMENTAL RESULTS AND INSIGHTS
Across reasoning-centric generation and editing, unified models show advantages over generation-only systems but still struggle to transfer inferred constraints into faithful images. The experiments also find that implicit prompts reduce generation performance and that editing remains difficult across model categories.
3.1 EXPERIMENT SETTINGS
- 21 representative models were evaluated across multimodal understanding, image generation, image editing, and unified multimodal categories.Source: §3.1 · p. 6
3.2 EVALUATION ON REAL-WORLD UNDERSTANDING AND GENERATION
- Across models, implicit prompts produced marked performance declines relative to category inputs, pointing to difficulty transferring reasoned constraints rather than rendering named entities.Source: Figure 4 · p. 7, §3.2 · p. 7
- BLIP3o achieved the highest overall understanding score of 0.974, while Janus-Pro scored 0.874; the authors conclude basic recognition and reasoning are not the main bottlenecks.Source: §3.2 · p. 7
3.3 EVALUATION ON REASONING-CENTRIC TEXT-TO-IMAGE GENERATION
- 0.362 was the highest numerical-reasoning score, achieved by Gemini-2.5-Flash-Image; BAGEL w/CoT scored 0.249 versus BAGEL’s 0.057.Source: §3.3 · p. 7
- Gemini-2.5-Flash-Image scored 0.759 in spatial layout; BAGEL w/CoT scored 0.448, above Qwen-Image at 0.368 and Ovis-U1 at 0.356.Source: §3.3 · p. 7
- GPT-Image-1 scored 0.813 and Gemini-2.5-Flash-Image 0.806 on implicit text rendering, while BAGEL w/CoT did not improve over BAGEL (0.120 vs. 0.163).Source: §3.3 · pp. 7–8
- Unified models outperform generation-only systems on reasoning-centric text-to-image generation, while editing gaps are narrower and all models remain constrained.Even the strongest proprietary models often fail at fine-grained local control and pixel-level information maintenance.Source: §3.3 · p. 7, Table 2 · p. 8, §3.4 · p. 8
3.4 EVALUATION ON REASONING-CENTRIC IMAGE EDITING
- Editing results show constrained abilities across models, including frequent failures by the strongest proprietary systems in fine-grained local control and pixel-level information maintenance.The three tasks are visual puzzle, visual logic, and reasoning perception.Source: §3.4 · p. 8
4 QUALITATIVE ANALYSIS
Qualitative cases show that models can infer or recognize targets yet fail to render them faithfully, while editing outputs exhibit distinct global and local errors. The analysis attributes this reasoning–generation misalignment to capability asymmetry, architectural bottlenecks, and limited interleaved training data.
- Generation outputs satisfy only part of coupled constraints, while editing examples show unfaithful puzzle reconstructions, digit errors, and failures to preserve regions.Source: §4 · p. 9
- Qwen-Image renders an entity when named but fails on its implicit prompt; BAGEL w/CoT infers “I Have a Dream” yet fails to render it directly.Refeeding BAGEL’s expanded prompt produces the target text, suggesting transfer into generation—not inference alone—is the challenge.Source: §4 · p. 9
- Judge-based scores can reward superficial resemblance or biased reasoning, whereas task-specific metrics penalize ground-truth mismatches and yield more consistent, interpretable evaluations.Source: §4 · p. 10, Figure 9 · p. 10
- The analysis identifies three proposed drivers: reasoning localized in the LLM, information loss through limited condition tokens, and too little interleaved reasoning-trace data.The paper describes these as factors identified through its quantitative ablations and qualitative case studies.Source: §4 · p. 10
5 CONCLUSION
GIR-Bench evaluates unified multimodal models across understanding, generation, and editing with task-specific metrics, revealing both their reasoning-task advantages and persistent difficulty transferring reasoning into faithful outputs. The authors frame the benchmark as research-focused and caution against downstream deployment without safeguards.
5 CONCLUSION
- GIR-Bench evaluates unified multimodal models across understanding, generation, and editing using explicit task-specific metrics rather than MLLM-as-a-Judge.The experiments find unified models surpass generation-only models on reasoning-intensive tasks but still struggle to transfer reasoning into faithful visual outputs.Source: §5 · p. 10
A ETHICS STATEMENT
- Benchmark images come from public open-source datasets or automated generation pipelines and are filtered to avoid inappropriate or harmful content.Source: A ETHICS STATEMENT · p. 13
- The authors withhold prompts or data that could enable malicious generation and say downstream deployment requires appropriate safeguards.Source: A ETHICS STATEMENT · p. 13
B.1 UNIFIED MULTIMODAL MODELS
The paper situates unified multimodal models as a shift from modality-specific systems toward models that handle understanding and generation together. It reviews architectural approaches and motivates comprehensive reasoning-centric benchmarks.
- Unified multimodal research has shifted from modality-specific architectures toward models handling understanding and generation across modalities.Source: §B.1 · p. 14
- Approaches discussed include early-fusion token transformers, pure autoregressive modeling, learnable query interfaces, and diffusion-based unified frameworks.Source: §B.1 · p. 14
- The cited systems include models with interleaved multimodal pretraining and emergent reasoning or image-manipulation capabilities, motivating comprehensive reasoning-centric benchmarks.Source: §B.1 · p. 14
B.2 BENCHMARKS FOR UNIFIED MULTIMODAL MODELS
Earlier benchmarks cover compositional alignment, editing fidelity, knowledge-image alignment, and reasoning prompts, but leave limits in reasoning evaluation and separating comprehension from generation. GIR-Bench-Edit instructions specify editing goals, preservation constraints, and output formats for its tasks.
B.2 BENCHMARKS FOR UNIFIED MULTIMODAL MODELS
- Earlier benchmarks span compositional alignment, surface-level editing, knowledge-image alignment, and reasoning prompts, but retain limits in reasoning coverage or evaluation that separates comprehension from generation.The described approaches include MLLM-based judging and evaluations that cannot disentangle understanding from generation.Source: §B.2 · p. 15
C IMAGE EDITING INSTRUCTIONS
- Each GIR-Bench-Edit instruction specifies an editing objective, constraints to preserve, and an output format, with placeholders filled by case-specific descriptions or categories.Figure 12 shows Edit examples, including segmenting a described region, solving Sudoku, and restoring a jigsaw puzzle.Source: C IMAGE EDITING INSTRUCTIONS · pp. 15–16, Figure 12 · p. 16
D MORE QUALITATIVE RESULTS
The qualitative examples span GIR-Bench-UGC, GIR-Bench-T2I, and GIR-Bench-Edit, illustrating typical model challenges and reasoning–generation misalignment across tasks.
D MORE QUALITATIVE RESULTS
- Figure 10 presents examples from GIR-Bench-UGC, Figure 11 from GIR-Bench-T2I, and Figure 12 from GIR-Bench-Edit.These figures provide representative qualitative results from all three benchmark components.Source: D MORE QUALITATIVE RESULTS · p. 16
- The cases illustrate typical challenges faced by current models across the benchmark's three components.The passage characterizes them as representative qualitative results.Source: D MORE QUALITATIVE RESULTS · p. 16
- The examples highlight reasoning–generation misalignment across the different tasks.The passage says this pattern is observed across the benchmark components.Source: D MORE QUALITATIVE RESULTS · p. 16
E ROBUSTNESS AND VALIDATION OF AUTOMATED EVALUATION METRICS
The paper reports strong correlation between its automated metrics and human judgment, while MLLM judges show lower consistency and score inflation. It also discusses the understanding–generation gap using quantitative ablations and qualitative cases.
E ROBUSTNESS AND VALIDATION OF AUTOMATED EVALUATION METRICS
- ρ ≈0.96 Pearson correlation with human annotation; MLLM-as-a-Judge approaches show lower consistency and score inflation, especially in lower-performance regimes.The correlation analysis aggregates scores across GIR-Bench tasks; Figure 13 depicts MLLM judge points above the diagonal in the lower-left quadrant.Source: E ROBUSTNESS AND VALIDATION OF… · p. 16, Figure 13 · p. 17
- Rare false negatives arise mainly with highly stylized or occluded objects, or severely distorted text; these edge cases do not disproportionately affect model rankings.The paper reports that relative rankings remain consistent and that the significant performance gap is robust to these metric fluctuations.Source: E ROBUSTNESS AND VALIDATION OF… · p. 17
F EXTENDED DISCUSSION: THE GAP BETWEEN UNDERSTANDING AND GENERATION
- Quantitative ablations and qualitative case studies are used to analyze the understanding–generation gap, identify its root causes, and propose research directions.The analysis draws on Figure 4 and Figure 5.Source: F EXTENDED DISCUSSION: THE GAP BETWEEN… · p. 17
F.1 ROOT CAUSES OF THE PERFORMANCE GAP
The paper attributes reasoning–generation misalignment to failures to activate or transmit reasoning, and to limited process-oriented training data. It discusses explicit reasoning, unified architectures, and reasoning-trace datasets as possible directions.
F.1 ROOT CAUSES OF THE PERFORMANCE GAP
- Models may know the relevant entity yet fail to activate that knowledge from an implicit prompt; the LLM's reasoned state may not reach or guide the image generator.The Charging Bull case contrasts success when the entity is explicitly named with failure when it must be inferred.Source: §F.1 · pp. 17–18
- A lightweight interface between an autoregressive LLM and generation head can compress semantic state, diluting or losing fine-grained constraints such as exact counts.The paper describes this information bottleneck in heterogeneous architectures.Source: §F.1 · p. 18
- Static image-text pre-training pairs omit generation processes, leaving models without interleaved reasoning-trace examples for decomposing abstract instructions into visual plans.The proposed trace format links a reasoning step, an intermediate visual state, and a refined image.Source: §F.1 · p. 18
F.2 FUTURE DIRECTIONS
- 0.057 to 0.249 accuracy on Numerical Reasoning for BAGEL w/ CoT; the paper proposes explicit textual plans as a bridge from implicit logic to generator-readable constraints.The paper reports this change as evidence that externalizing reasoning boosts performance.Source: §F.2 · p. 18
- Natively unified architectures, with text and image tokens treated equally in one backbone, are proposed to remove the heterogeneous interface bottleneck.The proposed design would let generation attend directly to uncompressed reasoning states.Source: §F.2 · p. 18
- Reasoning-trace datasets are proposed to supervise the reasoning-to-generation mapping with execution traces as well as final ground-truth images.The passage contrasts this with relying solely on end-to-end alignment.Source: §F.2 · p. 18
G CLARIFICATION FOR THE TEXT RENDERING METRIC (swc)
The section compares swc with standard accuracy (sacc) using “Make It Happen” generation scenarios. swc tolerates extra text and merged layouts while still rejecting incomplete target text.
G CLARIFICATION FOR THE TEXT RENDERING METRIC (swc)
- In Case B, swc credits valid target text despite chatty additions, while sacc fails because of its length penalty.The comparison covers different generation scenarios for the ground truth “Make It Happen”.Source: Table 3 · p. 18, G CLARIFICATION FOR THE TEXT RENDERING… · p. 19
- In Case C, swc identifies legible words in merged OCR output, while sacc penalizes missing whitespace.Tight layouts or artistic fonts can cause the OCR outputs to merge.Source: Table 3 · p. 18, G CLARIFICATION FOR THE TEXT RENDERING… · p. 19
- In Case D, both metrics penalize missing content, and swc rejects partial matches rather than crediting incomplete generations.The authors describe swc as a strict filter; “Make It Hap” is not credited.Source: Table 3 · p. 18, G CLARIFICATION FOR THE TEXT RENDERING… · p. 19