Have you ever wondered why some security camera footage appears washed out or too dark to distinguish details? This issue can be attributed to the concept of dynamic range, which refers to the balance between light and dark areas within an image. Understanding the concept of wide dynamic range (WDR) is crucial when discussing camera performance, as it plays a significant role in revolutionizing security surveillance.

What Is Wide Dynamic Range?

Wide dynamic range is a term used to describe the contrast ratio between the darkest and brightest color tones that a camera can capture in a single exposure. In video surveillance, WDR technology aims to effectively manage high-contrast environments by skillfully balancing the extremes. Its purpose is to prevent overexposure in bright areas and retain detail in dark areas, thereby avoiding under- or overexposed footage.

The measurement of a camera's dynamic range is expressed in decibels (dB), with the industry standard defined by IHS Markit stating that WDR should have a range of 60 dB or higher. However, it is not uncommon to find WDR cameras that offer dynamic ranges of 120 dB or even greater.

To illustrate the effectiveness of WDR technology in surveillance cameras, let's compare two images. In the first image without WDR, the camera's exposure is affected by the intense light coming from the window. As a result, the exterior view is overexposed, obscuring the details, while the room's interior appears too dark. However, in the second image with WDR enabled, the camera achieves balanced exposure. Both the bright outdoor scenery and the interior details of the conference room are captured clearly, ensuring visibility of both areas within the same frame.

How Does WDR Work?

WDR technology utilizes two processors, namely a light image processor and a dark image processor, to enhance the overall image quality and clarity.

When employing WDR technology in a PoE IP camera, the camera lens allows different amounts of light to enter specific areas of the image by utilizing varying shutter speeds. This control of light exposure helps achieve a well-balanced WDR image.

In areas with brighter lighting conditions, the camera lens employs a higher shutter speed, resulting in a shorter duration of light exposure for the camera sensor.

Conversely, in darker areas, the camera lens adopts a relatively slower shutter speed, allowing the sensor to capture more light over an extended period.

By combining the information from both images captured at different exposure settings, a final image is generated, which exhibits improved quality and clarity compared to a single-exposure image.

True WDR vs DWDR

True WDR (Wide Dynamic Range) and DWDR (Digital Wide Dynamic Range) are two technologies utilized in cameras to handle high-contrast lighting conditions.

True WDR employs a combination of hardware and software to capture multiple frames simultaneously at different exposure levels. These frames are then merged to create a single image with well-balanced exposure, ensuring that both the brightest highlights and darkest shadows retain their detail.

In contrast, DWDR operates solely through software manipulation on a single image. It adjusts the brightness of shadows and reduces the intensity of highlights. While DWDR is a cost-effective solution, it is generally less effective than True WDR and more suitable for lighting situations that are less challenging.

WDR vs HDR

WDR (Wide Dynamic Range) and HDR (High Dynamic Range) are two distinct image processing techniques that aim to improve image capture performance in high-contrast scenes. It is important to understand the differences between WDR and HDR to choose the appropriate surveillance technology that meets the requirements of various environments and image quality needs.

When comparing HDR and WDR, we recommend using WDR technology for security cameras due to the following advantages:

1. High-Speed Processing: WDR technology is supported by high-speed digital signal processing (DSP), enabling it to effectively handle dynamic images and videos.

2. Adjustable Exposure: WDR allows for the output of multiple frames with different exposure times, and each frame's gain can be individually set. This flexibility allows for precise control over the exposure settings.

3. Backlight Compensation: WDR enables imaging systems to compensate for intense backlighting surrounding subjects. This feature enhances the ability to distinguish features and shapes on the subject, ensuring clearer and more detailed images.

4. Better Low-Light Imaging: WDR technology excels at capturing images in low-light environments. It can effectively illuminate dark areas, ensuring security even in situations with low or no power supply.

5. Sharp Details: Compared to HDR, WDR technology produces images with exceptional sharpness and more pronounced details. This results in improved image quality and enhanced visibility of important information.

6. Cost-Effective: WDR cameras are more cost-effective in terms of installation and purchase price compared to HDR cameras. This makes WDR technology a practical choice for various surveillance applications, providing high-quality imaging at a more affordable cost.

Where to Use WDR Cameras?

WDR cameras find extensive use in environments characterized by demanding lighting conditions, particularly in areas where there is a significant contrast between bright and dark areas. Here are some common applications where WDR cameras are employed:

Entrance

The primary application for WDR cameras is monitoring the entrances of buildings. Whether it's a store, bank, ATM, transportation facility, restaurant, or hospital, every establishment has entrance doors that introduce bright light compared to the interior space. WDR cameras excel at compensating for areas that are excessively bright or dark and provide clear snapshots or videos.

Garage

In high-contrast scenarios where vehicles frequently enter parking lots, darkened garages, or cars with bright headlights approach surveillance cameras, WDR cameras can capture license plates with enhanced clarity.

Window Side

In areas where sunlight streams through glass panes, creating sharp contrasts of light and shadow within interior spaces, WDR cameras meticulously balance the intense glare from the outdoors with the softer indoor lighting. This ensures that every detail, from people's expressions near the window to the movement of curtains in the sunlight, is captured accurately.

Outdoor

Outdoor surveillance cameras often face the challenge of strong sunlight, which contrasts with the shadows of buildings or areas without direct sunlight. WDR cameras effectively compensate for these differences, providing clear and balanced images.

To further enhance security with high-quality video capture in challenging lighting conditions, Linovision offers a range of security cameras equipped with WDR technology. These options include the 4K bullet PoE IP camera, the 4MP dome network camera, the 4MP turret network camera. Linovision not only provides security cameras but also offers comprehensive video surveillance solutions tailored for enterprises, retail supermarkets, campuses, and other specific needs.