Steering Generative Models for Accessibility: EasyRead Image Generation
Authors: Nicolas Dickenmann, Yanis Merzouki, Sonia Laguna, Thy Nowak-Tran, Emanuele Palumbo, Julia E. Vogt, Gerda Binder
Organizations: Department of Computer Science, ETH Zurich, Switzerland · Unicef Digital Impact Division, Valencia, Spain · ETH AI Center, ETH Zurich, Switzerland
EasyRead pictograms are simple, visually clear images that represent specific concepts and support comprehension for people with intellectual disabilities, low literacy, or language barriers. The large-scale production of EasyRead content has traditionally been constrained by the cost and expertise required to manually design pictograms. In contrast, automatic generation of such images could significantly reduce production time and cost, enabling broader accessibility across digital and printed materials. However, modern diffusion-based image generation models tend to produce outputs that exhibit excessive visual detail and lack stylistic stability across random seeds, limiting their suitability for clear and consistent pictogram generation. This challenge highlights the need for methods specifically tailored to accessibility-oriented visual content. In this work, we present a unified pipeline for generating EasyRead pictograms by fine-tuning a Stable Diffusion model using LoRA adapters on a curated corpus that combines augmented samples from multiple pictogram datasets. Since EasyRead pictograms lack a unified formal definition, we introduce an EasyRead score to benchmark pictogram quality and consistency. Our results demonstrate that diffusion models can be effectively steered toward producing coherent EasyRead-style images, indicating that generative models can serve as practical tools for scalable and accessible pictogram production.
Figures & tables
EasyRead design principle
Property description
Metric (score)
Metric description
Low visual clutter
Few colors and minimal visual noise
Palette Complexity ( spalette )
Color simplicity
Simple geometry
Clear shapes with smooth outlines
Edge Density ( sedges )
Fine-grained line detail
Clear focus
One visually dominant object
Saliency Concentration ( ssaliency )
Concentration of visual attention
Strong separation
Foreground clearly distinct from background
Foreground–Background Contrast ( scontrast )
Perceptual foreground–background separation
Stable layout
Main content centered and well sized
Centering Error ( scentering )
Alignment with the image center
Consistent strokes
Uniform and readable outline thickness
Relative Stroke Thickness ( sstroke )
Outline consistency and readability
Table 1. EasyRead design principles and corresponding metrics.
Figure 1. Our pipeline to generate EasyRead pictograms. Training (Left) : Input data is preprocessed, captioned using BLIP and augmented before fine-tuning Stable Diffusion v1.5 using Low-Rank Adaptation (LoRA). A unique instance token (sks) is used to learn the EasyRead style. Inference (Right) : The model generates new pictograms by combining the learned style token (sks) with a descriptive prompt and specific color constraints to ensure stylistic consistency. Flowchart of the EasyRead pictogram generation pipeline divided into Training and Inference phases. The Training section illustrates sample data diverging into three parallel steps: Image Preprocessing, BLIP (outputting the caption "Two girls and a boy are standing on a crosswalk"), and ARASAAC-only augmentation (outputting "background color: red; skin color: black; hair color: gray"). These three outputs and an Instance Token are using in training LORA Adapters stacked atop Stable Diffusion version 1.5. The Inference section demonstrates an Instance Token, a text prompt ("A teacher writing on a chalkboard"), and color constraints ("background color: white; skin color: white; hair color: red") feeding directly into the identical model stack to output a matching generated pictogram.
Model
ERS ↑
CLIP ↑
SD v1.5 (GT)
0.40±0.07
24.33±2.75
Ours (LoRA)
0.47±0.06
31.15±2.88
Table 2. Quantitative comparisons between our model and the Stable Diffusion v1.5 baseline on the EasyRead score and CLIP similarity score are summarized as mean ± standard deviation over 275 samples.
GT (SD v1.5)
Ours (LoRA)
Global Symbols
Nano Banana Pro
Prompt (without sks token)
The skyline of New York City at night; background color: black; skin color: black; hair color: blonde
A mom reading to a happy child; background color: red; skin color: black; hair color: blonde
A firefighter on a ladder extinguishing a fire; background color: yellow; skin color: white; hair color: brown
Table 3. Qualitative single-shot comparison of baseline Stable Diffusion v1.5, our model and external closed-source models (Global Symbols [7] and Nano Banana Pro [8]) on identical prompts.
Figure 2. Qualitative sample of four generations of our model at different seeds with the prompt: The eifeltower in Paris; background color: white; skin color: white; hair color: black . Four generated images of the Eiffel Tower showing variations from the same text prompt. The images are arranged in a 2 by 2 grid. Despite the prompt explicitly requesting a white background, the outputs vary significantly: \begin{itemize} \itemTop-left: A stylized, colorful drawing of the tower situated above a yellow archway against a light blue sky. \itemTop-right: A sketch-style, distant view of the tower at the end of a path with buildings in the background and a blue sky. \itemBottom-left: A drawing of the tower standing on a gray path bordered by bright green grass, set against a plain white sky. \itemBottom-right: A simple black outline of the tower isolated on a pure white background, being the only image that strictly adheres to the background color constraint. \end{itemize}
Appendix figures & tables5 assets
Supplementary material from the paper’s appendix.
Appendix
Table 4. Examples of the three datasets in our corpus: ARASAAC pictograms, OpenMoji icons, and LDS symbolic illustrations. Although all are simplified drawings, they exhibit clear and systematic stylistic differences in visual abstraction, line weight, and compositional conventions.
Table 7
Scene Description
Background
Skin
Hair
The skyline of NYC at night
Red
White
Blonde
A person watering a houseplant
Green
Black
Brown
A child brushing their teeth
Blue
Asian
Dark Brown
A doctor listening to heartbeat
Yellow
Mulatto
Gray
A firefighter climbing a ladder
Black
Aztec
Dark Gray
A teacher writing on a chalkboard
White
White
Red
Appendix
Table 7. Validation Dataset prompts and control attributes
Figure 3. Four samples at different seeds generated by the closed-source Nano Banana Pro ( Google DeepMind, 2025 ) model with the prompt: A pictogram of the skyline of New York City at night . A 2 by 2 grid displaying four different generated pictograms of the New York City skyline at night: \begin{itemize} \itemTop-left: A black silhouette of the skyline against a dark blue background, featuring a white crescent moon and stars, with the words ``NEW YORK CITY'' written in black text below the buildings. \itemTop-right: A white outline and solid white shapes forming the skyline against a solid black background, with a white crescent moon and stars. \itemBottom-left: A skyline with dark silhouettes and yellow glowing accents, framed within a dark blue circular background containing a yellow crescent moon and stars. \itemBottom-right: A black silhouette and outline of the skyline against a very pale, off-white background, featuring a black crescent moon and stars. \end{itemize}
Prompt (without sks token)
Generation 1
Generation 2
Generation 3
Generation 4
Generation 5
A street market with food stands; background color: red; skin color: mulatto; hair color: black
A person taking a photograph; background color: white; skin color: asian; hair color: red
A soccer player kicking a ball; background color: green; skin color: asian; hair color: darkBrown
A cup of coffee on a table; background color: green; skin color: white; hair color: darkGray