Advanced image sensors and HDR processors are transforming vehicle vision systems to handle extreme lighting conditions safely.
14 Dec 2025 | 4575 Views | By Jens Benndorf, Tessolve
While the human eye instinctively adapts to rapidly changing lighting conditions, vehicle cameras and their “brain” — the image signal processor (ISP) — face a far greater challenge. To keep these systems both cost-efficient and fast, automotive cameras typically use neither an iris nor an ND (neutral density) filter to ...
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While the human eye instinctively adapts to rapidly changing lighting conditions, vehicle cameras and their “brain” — the image signal processor (ISP) — face a far greater challenge. To keep these systems both cost-efficient and fast, automotive cameras typically use neither an iris nor an ND (neutral density) filter to regulate incoming light. In real driving scenarios, scene contrast can reach up to 160 dB in critical situations such as bright sunlight at tunnel entrances, headlights on dark roads, LED traffic lights, or reflections on wet asphalt. At the same time, there is zero tolerance for safety-critical artefacts like ghosting or LED flicker.
Dynamic range describes the ratio between the brightest and darkest signal levels an image sensor can accurately capture. To faithfully reproduce a high-contrast scene, the sensor’s dynamic range must match or exceed the scene’s contrast.
Only recently have image sensors capable of reaching 160 dB dynamic range without safety-critical artefacts become available. These sensors combine several sophisticated HDR techniques — such as multiple conversion gains, charge overflow, and staggered exposure schemes.
Side note: In small automotive cameras, the optics will inevitably introduce stray light, limiting the effective dynamic range in extreme contrast situations. Still, a 160 dB sensor (including stray light) retains far more critical information than a sensor whose signal simply clips. Even with imperfect optics, extremely high dynamic range sensors make clear sense in safety-critical systems.
To process such vast dynamic-range imagery, specialized HDR ISPs are required. These processors are typically implemented in hardware to achieve acceptable power consumption and are offered as semiconductor-based digital IP for integration into complex systems.
Real-World Applications of HDR ISPs
HDR images may use up to 28 bits per channel to represent a 160 dB signal in linear space.
One key use case is rendering this high dynamic range content as a natural-looking image on a display — for instance, in digital mirrors. Most displays today support just 8 to 10 bits per channel. Therefore, advanced tone-mapping algorithms, especially grid-based local tone mapping, are essential. They preserve both global contrast and fine details when compressing a 28-bit HDR frame to an 8- or 10-bit output.
The comparison below illustrates the difference: global tone mapping looks fine, but local tone mapping reveals additional subtle structures — the kind of details that might correspond to a pedestrian in the shadows or a bright vehicle emerging from a sunlit tunnel.
Another important application is machine-vision data generation for AI-driven perception systems. The HDR preprocessing required for object detection differs substantially from that used to produce natural images for human viewing — yet local tone mapping remains essential here as well.
To address these diverse demands, HDR ISPs use a modular architecture that scales seamlessly across application requirements. This flexibility enables customers to fine-tune performance, power efficiency, and silicon area, while allowing easy integration of new features or pipeline optimizations.
HDR ISPs are already embedded across a wide range of automotive domains, particularly:
Beyond automotive, HDR ISPs are becoming essential across industrial automation, security, robotics, quality control, and consumer electronics. In industrial environments — where lighting may change rapidly — real-time ISP processing enables fast and accurate machine vision. In consumer markets, HDR ISPs power action cameras, smart home devices, drones, and wearables, ensuring stable, high-quality imagery in all lighting conditions.
Overall, HDR ISP technology offers transformative potential across numerous sectors, playing an increasingly vital role in safety-critical and data-driven applications.
The Critical Role of Semiconductors
Semiconductors are central to the rising capabilities of automotive and autonomous mobility systems. They integrate complex technologies into power-efficient packages, enabling smarter, safer operation. Their roles include:
Conclusion
Although they operate behind the scenes, HDR ISPs are becoming a cornerstone of road safety and many other industries. They capture, interpret, and process complex imaging data in real time and very low latency. As ADAS and autonomous driving technologies continue to advance, the ability for vehicles to “see” clearly across extreme contrast conditions becomes increasingly crucial — and this is precisely where powerful semiconductors and HDR ISPs excel.
With global demand for smarter, safer, and more reliable mobility rising, HDR ISPs are rapidly becoming foundational components in modern vehicles. Continued innovation will be essential to meet evolving safety standards and unlock the full potential of next generation driving systems.
Beyond automotive, HDR ISPs are now proliferating wherever high-dynamic-range imaging must be processed — a trend that will accelerate as more HDR sensors of varying pixel counts and form factors enter the market.
Jens Benndorf is the CEO of Dream Chip Technologies & Head of Custom Silicon at Tessolve. Views expressed are the author's personal.