Low-Light Image Enhancement: YUV vs RAW – What’s the Difference?

In the world of embedded vision—whether for mobile phones, surveillance systems, or smart edge devices—image quality in low-light conditions can make or break user experience. That’s where advanced AI-based denoising algorithms come into play.

At our company, we specialize in real-time low-light video enhancement using deep learning (CNNs). Our technology supports both RAW denoising and YUV denoising, optimized for embedded camera systems. But how do these two approaches differ, and which one is right for your pipeline?

Let’s dive into the differences between YUV and RAW domain low-light enhancement, from both an image quality and technical integration perspective.

RAW Denoising: Closer to the Sensor, Closer to the Truth

RAW denoising operates on the unprocessed sensor data, usually in Bayer format, before any major image signal processing (ISP) occurs.

Advantages:

  • Maximum information: RAW data retains the full dynamic range and bit depth captured by the sensor. This gives AI/CNN models more to work with—especially in dark scenes.
  • Reliable, high-quality noise removal: Because RAW data is not yet processed or transformed by the ISP and its noise characteristics are more consistent and predictable, denoising can be applied more effectively—suppressing noise without introducing color artifacts or losing fine detail, and with less need for sensor-specific tuning.
  • Post-denoise ISP optimization: One of the key advantages of the RAW domain is that after denoising, the ISP has much better opportunities to enhance the image—for example, to sharpen it and adjust colors according to the customer’s preferences.

Challenges:

  • Integration complexity: Integrating into the RAW domain can be difficult—or even impossible—depending on the system architecture. Access to RAW data is often limited or proprietary in the SoCs.
  • High compute & bandwidth: RAW data is large and typically requires more processing power and memory bandwidth, which may not suit every embedded platform.

YUV Denoising: Real-Time Ready, Deployment Friendly

YUV denoising, on the other hand, takes place after most ISP stages. The image has already been demosaiced, color-corrected, and converted into a format optimized for compression and display.

Advantages:

  • Easier integration: YUV is a standardized output format across most camera pipelines. This makes YUV denoising much easier to deploy, especially in real-time video scenarios.
  • Lightweight models: Because the data is smaller and already preprocessed, AI-based YUV denoise models can run more efficiently on edge devices.
  • Live video enhancement: For use cases like surveillance or automotive, YUV denoising is often the more practical and scalable choice.

Challenges:

  • Lower fidelity: By this stage, much of the original sensor information is lost. Noise patterns are more complex, and recovering fine detail becomes more difficult.
  • Sensor-specific tuning: Each sensor’s ISP behaves differently, requiring per-sensor tuning and model finetuning.

Choosing the Right Domain: It Depends on Your Pipeline

There’s no one-size-fits-all answer. The decision between RAW and YUV denoising depends heavily on:

  • Access to the image pipeline: Can you tap into the RAW feed before the ISP? If not, YUV may be your only option.
  • Compute and memory budget: RAW enhancement is heavier. For lightweight platforms, YUV might be the only feasible choice.
  • Hardware constraints: Some NPUs support only 8-bit operations (INT8) and lack 16-bit support, which makes high dynamic range RAW denoising impractical. In such cases, the pipeline is effectively forced into the YUV domain.
  • Time-to-market: If fast integration is key, YUV denoise wins. If you want maximum image quality and control, RAW denoise might be worth the extra effort.

At the end of the day, the right choice comes down to customer needs and pipeline constraints. That’s why we offer both solutions—each optimized for its domain and use case.

 

ISP noise reduction vs Visidon RAW denoise in 0,05 lux lighting level
ISP noise reduction vs Visidon YUV denoise in 0,05 lux lighting level

 

Final Thoughts

Whether you’re working with YUV or RAW, denoising algorithms powered by AI/CNNs have significantly raised the bar in low-light video enhancement. While RAW gives you maximum image quality and post-processing flexibility, YUV gives you faster deployment and real-time performance.

And we’re here to help you get the best of both worlds—real-time, embedded AI-powered low-light enhancement tailored to your product.

Want to see side-by-side results or learn which domain is best for your system? Get in touch.

Keywords: AI, CNN, denoising algorithms, RAW denoise, YUV denoise, RAW denoising, YUV denoising, low-light enhancement, embedded camera systems, real-time video enhancement.