We love sharing new features with you, but we don’t often talk about the work that doesn’t show up in a list of new features. There’s a lot of it, and it has a real impact on your experience with ON1 Photo RAW. Today, around two-thirds of our engineering team is working on maintaining, modernizing, and improving existing code. Here’s an honest look at what that means and why it matters.

ON1 Photo RAW Performance: Two Big Modernization Projects

We’re wrapping up two large platform migrations that have been in progress for a while.

From DirectML to WinML on Windows

DirectML is the framework we currently use for AI inference on Windows. It’s a solid, general-purpose approach to GPU processing and it’s served us well. WinML, the framework we’re moving to, works differently: it uses vendor-specific Execution Providers that compile and cache AI models for your exact hardware in real time. Instead of a one-size-fits-all solution, your GPU or NPU runs the model the way it was built to run it. We’ve already seen 2x speed improvements on some GPUs. This migration also unlocks NPU processing, which will matter more as NPU-equipped hardware becomes the norm.

From OpenGL to Platform-Native Graphics

We currently use OpenGL for rendering, which was the industry standard not long ago. The ecosystem has moved on. We’re migrating to Direct3D 12 on Windows, Metal on Mac and iOS, and Vulkan on Android. The difference for you will be most noticeable with deep effects stacks and heavy brushwork, where performance today is more limited. On our end, these APIs also give us better debugging tools and compute options, which improves stability and opens up development paths that weren’t available before.

Making Existing Features Better

Some of our work isn’t about adding tools. It’s about making the tools you already use work better.

A Significant Update to Our Raw Engine

We built our own raw processing engine from scratch about a decade ago. We wanted full control over speed and output, and building it ourselves was the right call. The core results have been largely unchanged since then, which is something you’ve noticed and told us about. That’s about to change. We’re making significant improvements to the raw engine. The goals are specific: shadows and highlights sliders that behave more predictably and affect only their intended tonal ranges, and default processing that delivers more color and punch straight out of the camera. We’re making real progress and will share results soon.

Better Retouching Results

You’ve told us that the Perfect Eraser and our generative AI inpainting tools can produce better results. We agree. We’re putting significant R&D into both, and we’re confident we can deliver meaningful improvements. More to come on this.

Paying Down Technical Debt

Every long-lived application accumulates technical debt. Paying it down is unglamorous work, but skipping it makes everything else harder.

Bug fixes are the most visible form. We do those constantly, but it goes deeper. Coding standards evolve, and legacy code needs regular refactoring to stay clean and maintainable. We’re currently refactoring a large core area of the codebase that handles document management and plugins. This work will reduce the overall size of the codebase, improve stability, and make future development faster.

Overhauling the Component Manager

ON1 Photo RAW ships with thousands of components: AI models, camera and lens profiles, presets, borders, textures, and more. We separated these from the main installer years ago so downloads could be smaller and faster, with components fetched in the background as needed. That works well on fast connections, but it can be slow and disruptive in other situations.

We’re making significant changes to give you more control over when components install and to make the process far less intrusive. As part of this work, we’ve also cleaned up application startup and shutdown. Both will be faster and more consistent.

A Word on Stability and Performance

You’ll notice stability and performance come up throughout this post. That’s intentional. We hear your feedback on these, and we feel the shortcomings ourselves. We’re dedicating more resources to these areas than at any point in the product’s history.

Progress here rarely comes from fixing a handful of bugs. In a system as large and interconnected as Photo RAW, real gains come from the kind of structural work I’ve described above. It takes time, and it won’t always show up in a release note. It is the foundation everything else is built on, and the work we’re doing now is what makes a faster, more stable Photo RAW possible.

We’re excited for you to feel the difference.

Thanks for reading,

Dan Harlacher
VP of Product, ON1