HDR Camera Module: Sensor-Level High Dynamic Range in Embedded Cameras
A standard CMOS sensor covers roughly 60 to 70 dB of scene contrast. A vehicle leaving a tunnel at midday spans well past 120 dB, and everything outside the sensor’s range arrives as clipped white or crushed black that no amount of post-processing recovers. That gap is what an HDR camera module exists to close, and Vadzo Imaging closes it on the sensor rather than in software, across USB, MIPI CSI-2, GigE, and FPD-Link modules reaching 100 to 140 dB. What follows is the technique behind each HDR camera module, the dB figure to specify, and the parts that carry it.
What Is HDR Camera Hardware?
An HDR camera captures bright and dark regions of the same frame without clipping either, using a sensor that extends its own range instead of an ISP stretching contrast afterwards. On a Vadzo HDR embedded camera, this is board-level hardware: a 32 x 32 mm or 38 x 38 mm module with an M12 or S-mount lens, an HDR-capable sensor, and an on-board ISP handling tone mapping, temporal noise reduction, and dewarping before anything reaches the host. The Falcon-821CRH carries an AR0821 with embedded HDR exceeding 140 dB, the Bolt-830CRH carries an AR0830 in LI-HDR mode, and both drop into a Jetson, i.MX, Raspberry Pi, or x86 host as an OEM part rather than a boxed camera. That distinction matters in procurement: an HDR embedded camera is specified by sensor, dB figure, and HDR mode, not by a housing.
What Is Dynamic Range in Camera Terms?
Dynamic range is the ratio between the brightest and darkest signal a sensor records in one frame, written in decibels, and each 6 dB is one stop or a doubling of that ratio. A standard module at 70 dB covers about 3,200 to 1; a 100 dB dynamic range part covers 100,000 to 1; a 140 dB HDR camera such as the Falcon-821CRS or Bolt-821CRS covers ten million to one, and a 140 dB HDR camera is the only class that holds detail at both ends of a tunnel mouth. Those are not marketing steps but different sensor architectures, which is why the Falcon-2020CRS is published at 100 dB using line-interleaved readout. When comparing modules, compare the dB figure and the mode that produces it, because a 100 dB dynamic range claim from frame stacking and one from a single exposure behave nothing alike in a moving scene.
How Many dB of Dynamic Range Do I Need?
The number follows the lighting the camera will actually face, not the highest figure on the datasheet. Indoor and controlled lighting is served by 70 to 80 dB, which is why an embedded vision HDR build for a lit inspection cell rarely needs a flagship part; outdoor and mixed lighting wants 100 dB or more, putting the Falcon-830CRH or Bolt-2020CRH in range; an automotive HDR camera for ADAS or smart city work wants about 120 dB with flicker mitigation, where the Falcon-246CRS sits. Paying for 140 dB on an indoor embedded vision HDR application buys nothing a 100 dB module would not deliver, and specifying 80 dB for a loading bay with a sunlit doorway guarantees a blown-out or blacked-out region in every frame.
Sensor-Level HDR and ISP Tone Mapping Are Not the Same Thing
Sensor-level HDR extends the range at capture, before the data is quantized, so the information exists in the file; an ISP contrast stretch only redistributes information already captured and cannot invent a highlight the sensor clipped. Every HDR figure Vadzo publishes is sensor-level HDR, and the HDR tone mapping ISP on the USB modules runs after it, compressing that wide capture into a viewable 8-bit stream along with temporal noise reduction and dewarping. The order is what matters: an HDR tone mapping ISP fed by a 140 dB capture from a Falcon-821CRH produces a usable image of a tunnel exit, while the same ISP fed by a 70 dB capture produces a well-graded picture of clipped data.
HDR Methods Used on Vadzo Sensors
Multi-Exposure HDR
Multi-exposure HDR takes two or more frames at different exposure times and blends them, which reaches a high dB figure cheaply because the sensor itself needs no special pixel structure. The cost is time: the frames are captured sequentially, so anything moving between them appears as a ghost or a tear at the blend boundary, and frame rate drops with the number of exposures. Vadzo uses multi-exposure HDR only where the scene is static, and the modules below instead use the single-readout methods that follow.
In-Pixel HDR (iHDR)
In-pixel HDR gives each pixel more than one storage node, so long and short integrations are captured and combined on-chip within a single readout. An iHDR camera such as the Falcon-1335CRA, a 13MP AR1335 module with ROI-based auto exposure and autofocus, therefore holds a full frame rate and shows no blending error, since there is no second frame to align. The Bolt-1335CRA is the MIPI iHDR camera built on the same AR1335, quoted around 120 dB in Quad HDR terms, so in-pixel HDR spans both interfaces.
Line-Interleaved HDR (LI-HDR)
Line-interleaved HDR alternates high-gain and low-gain rows inside one readout, reconstructing a wide-range frame from a single exposure without ghosting. The Falcon-830CRH and Bolt-830CRH, both AR0830 HyperLux LP parts at 8MP 4K, run line-interleaved HDR with Wake-on-Motion, and the 20MP AR2020 in the Bolt-2020CRH and Falcon-2020CRS uses the same approach for its 100 dB figure. A Li-HDR camera module suits perimeter surveillance, drones, and autonomous mobile robots precisely because the vehicle and the scene both move, and on a Li-HDR camera module the frame rate does not drop to buy the extra range.
Extended HDR and Enhanced Dynamic Range
An eHDR sensor adds a brief secondary exposure immediately after the main integration to recover highlights, which is how the Falcon-246CRS reaches 120 dB with adaptive local tone mapping and how the AR0821 eHDR sensor in the Falcon-821CRS exceeds 140 dB with exposure ratio control. Extended dynamic range, written eDR, is a separate single-exposure mode worth about 73 dB that layers on top: the Bolt-2020CRH publishes 100 dB line-interleaved HDR and 73 dB eDR as two selectable modes. An eDR mode camera running in its extended dynamic range setting is the lower-power option when the scene does not need the full HDR budget, and the Falcon-830CRS is the eDR mode camera on the USB side of the same family.
Does HDR Cause Motion Artifacts?
Only when the HDR comes from stacking frames. Sequential exposures blended into one picture produce ghosting on anything that moved between them, which is why single-exposure HDR is the method used across the Vadzo HDR range: iHDR on the Falcon-1335CRA, LI-HDR on the Falcon-830CRH and Bolt-830CRH, eHDR on the Falcon-821CRH. Because all of these reconstruct the wide-range frame within one readout, there is no temporal offset to misalign, and single-exposure HDR therefore holds full frame rate as well. For a drone, an AMR, or a vehicle camera, that property decides the part before the dB figure does.
HDR over USB, MIPI CSI-2 and GigE
HDR USB Camera
An HDR USB camera in the Falcon range is UVC compliant, so Windows and Linux hosts enumerate it without a driver, and the on-board ISP delivers tone-mapped dual streams straight to the application. That makes a UVC HDR camera such as the Falcon-830CRH or Falcon-2020CRS the fastest HDR path onto an x86 or Jetson host, since a UVC HDR camera needs no kernel work before the first frame arrives, and the USB 2.0 modules extend the same HDR USB camera idea to USB 2.0 for lower-bandwidth or on-board-storage designs.
HDR MIPI Camera
An HDR MIPI camera in the Bolt range connects over 2-lane or 4-lane CSI-2 directly to the SoC, which removes the USB controller from the path and lowers both power and latency. HDR mode, exposure, gain, and frame rate are exposed through V4L2 HDR control in the supplied driver package, so a Bolt-821CRS or Bolt-2020CRH is configured with the same V4L2 HDR control calls the rest of the pipeline already uses on Jetson, i.MX, Rockchip, or Raspberry Pi.
HDR GigE Camera
An HDR GigE camera module puts the module up to 100 m from the host over Cat5e or Cat6, with the encoder and ISP on the camera, which is what the Innova-678CRS does with an IMX678 Clear HDR sensor and the Innova-821CRS with an AR0821. Where the scene has a wide contrast range, and the host cannot sit beside the camera, an HDR GigE camera is the only one of the three interfaces that solves both problems at once.
Vadzo HDR USB 3.x Camera Modules
Model | Sensor | Resolution | HDR mode | Buy Now |
Falcon-246CRS | onsemi AR0246 | 2MP 1080p | eHDR with ALTM, 120 dB, eDR | |
Falcon-233CRS | onsemi AR0233 | 2MP 1080p | HDR with LFM, extended temperature | |
Falcon-821CRH | onsemi AR0821 | 8.3MP 4K | Sensor-level eHDR above 140 dB, autofocus | |
Falcon-830CRH | onsemi AR0830 | 8MP 4K | LI-HDR with eDR, autofocus | |
Falcon-2020CRS | onsemi AR2020 | 20MP | 100 dB LI-HDR with eDR | |
Falcon-521CRH | onsemi AR0521 | 5.1MP | HDR with extended NIR | |
Falcon-1335CRA | onsemi AR1335 | 13MP 4K | iHDR, autofocus |
Vadzo HDR USB 2.0 Camera Modules
Model | Sensor | HDR mode | Buy Now |
Merlin-291CRS | Sony IMX662 | Clear HDR, on-board dewarping | |
MerlinPlus-662CRS | Sony IMX662 | Clear HDR, on-board storage | |
MerlinPlus-234CGS | onsemi AR0234 | HDR sensor, dewarping, on-board storage | |
MerlinPlus-521CRS | onsemi AR0521 | HDR-class sensor, on-board storage |
Vadzo HDR MIPI CSI-2 Camera Modules
Model | Sensor | Resolution | HDR mode | Buy Now |
Bolt-821CRS | onsemi AR0821 | 8.3MP 4K | Sensor-level HDR above 140 dB | |
Bolt-830CRS | onsemi AR0830 | 8MP 4K | LI-HDR with eDR | |
Bolt-830CRH | onsemi AR0830 | 8MP 4K | LI-HDR with eDR, autofocus | |
Bolt-2020CRH | onsemi AR2020 | 20MP | 100 dB LI-HDR, 73 dB eDR, autofocus | |
Bolt-1335CRA | onsemi AR1335 | 13MP 4K | iHDR, autofocus |
Vadzo HDR GigE Camera Modules
Read the four tables by constraint. Lighting sets the dB figure, so an indoor cell takes any part on the list, while a tunnel mouth or a sunlit doorway needs the AR0821. Motion sets the HDR mode, ruling out frame stacking and pointing at iHDR, LI-HDR, or eHDR parts. Host distance sets the interface: USB for a host within a few meters, MIPI CSI-2 for a module bolted to the SoC, GigE for 100 m of cable. Road-facing work adds flicker mitigation as a hard requirement, which narrows the list to the Falcon-233CRS and Falcon-823CRS.
Frequently Asked Questions
What is an HDR camera?
A camera whose sensor captures bright and dark parts of the same scene without clipping either, rather than an ISP stretching contrast after capture. The range is extended at the point of capture, so the highlight and shadow information exists in the data instead of being reconstructed from what survived. On a board-level module, this means an HDR-capable sensor plus an on-board ISP for tone mapping, noise reduction, and dewarping, delivered as an OEM part for a Jetson, i.MX, Raspberry Pi, or x86 host. A standard sensor covers about 60 to 70 dB, while HDR parts run from 100 dB to 140 dB. Every HDR figure in the Vadzo range is sensor-level rather than software-applied.
What is dynamic range in a camera?
The ratio between the brightest and the darkest signal recorded in a single frame, expressed in decibels, where every 6 dB is one additional stop. Seventy decibels is roughly 3,200 to 1; one hundred decibels is 100,000 to 1; and 140 dB is about ten million to one. The figure is set by the sensor architecture, not by exposure settings or by processing applied afterwards. Two modules quoting the same dB can behave very differently if one reaches it by stacking frames and the other within a single readout. Vadzo publishes both the dB figure and the HDR mode for every module so the two can be compared properly.
How many dB of dynamic range do I need?
Indoor and controlled lighting is generally served by 70 to 80 dB; outdoor and mixed lighting should target 100 dB or more; automotive, ADAS, and smart city work wants around 120 dB together with flicker mitigation. Specifying below the scene requirement produces clipped highlights or blocked shadows in every frame, and no downstream processing recovers them. Specifying far above it costs money without changing the picture. The Vadzo range covers 100 dB through 140 dB across USB, MIPI CSI-2, and GigE, so the part can be matched to the scene.
Does HDR cause motion artifacts?
Depends entirely on how the HDR is produced. Multi-exposure HDR captures frames sequentially and blends them, so anything that moves between exposures ghosts or tears at the blend boundary, and frame rate falls as exposures are added. Single-exposure methods reconstruct the wide-range frame inside one readout, so there is no temporal offset and no ghosting, and full frame rate is retained. In-pixel HDR, line-interleaved HDR, and extended HDR all work this way. The Vadzo HDR modules use these single-readout methods, which is why they suit drones, autonomous mobile robots, and vehicle cameras.
What is LED flicker mitigation?
An exposure technique that aligns the integration window with the complete cycle of a pulse-width-modulated LED, so the camera never samples the light during an off period. Without it, LED traffic signals, brake lights, and matrix signage can appear dark or partly broken in individual frames. That is a safety failure in any perception system that has to read a signal state, not merely a cosmetic defect. It matters most in automotive, ADAS, and smart city deployments where nearly all lighting is now pulse-driven. Vadzo implements it on the Falcon-3C10CRS, Falcon-233CRS, and Falcon-823CRS alongside their HDR modes.
