Jack, this seems to be a trend for Asian manufacturers right now! Innovating new terms for WDR :)
We'll ask Vivotek for an explanation of what technically each version/type does.
That said, we have only ever found 2 types of WDR - 'electronic' / fake and multi-imager / true - see our WDR Tutorial.
IPVMU Certified | 11/14/13 04:41pm
Hi John, the whole topic of WDR is very confusing, isn't it. God I hate "specsmanship"...! Anyhow, there are some new technologies being introduced as substitutes for the traditional "dual shutter speed" method of WDR. Many end-users seem to complain about the reduced effective frame rate of the dual shutter speed WDR implementation. (I think it looks weird also!) Anyhow, the R&D engineers have been experimenting with "gamma stretching" and other effects to produce images that provide a "WDR-like" image in real time. We just demonstrated this latest technology to our OEMs at the ASIS Show. I think it has ood potential for scens such as night-time with auto headlights/taillights and license plate recognition. There will undoubtedly be various "marketing" termonology for these new functions since many camera vendors will surely develop/license the process. In any event, the main goal of a "WDR" (or similar) functions is to provide useable video in challenging (real world) lighting conditions. It should be exciting when this new "WDR" technology makes the mainstream...
IPVMU Certified | 11/14/13 05:16pm
The dual shutter spped method for WDR effectively reduces the frame rate in 2 since the resultant combined image will be mostly of the nominal shutter speed (1/60-sec for NTSC, 1/50-sec for PAL) exposure. The actual camera output is still full frame rate but as you know the combined image is stored in memory and repeated (frame doubling). This IP Camera course has taught me a lot about the "80%" of the market that we are not involed in (our market is high end PTZ camera blocks). As you know I work for a camera block manufacturer, (I know you don't want these forums to be about manufacturers - but I know you can determine my company from my profile...). Anyhow, our latest DSP contains multiple gamma-stretching functions, Automatic DeFog, and a function that stretches the dark parts of the image while leaving the remainder of the image unaltered. We have a block with this technology at our OEMs for evaluation now. I am not sure if you want me to (or if I even can... no NDA...) list further details (model numbers, production timelines, etc.). I don't want the forum to be used as a sales push - that's not my style, or desire. I just though I should mention that some exciting new technology will be mainstream during 2014.
IPVMU Certified | 11/16/13 11:16pm
Hi Alex, For our SD NTSC and PAL camera blocks that use full frame rate progressive scan image sensors and full frame rate progressive processing the interlaced video output fields are derived from the image sensor frames as follows: For the first image sensor frame, the output field (Field A) is taken from the odd numbered scan lines of the sensor frame. For the next image sensor frame, the output field (Field B) is taken from the even numbered scan lines of the sensor frame. So basically the unused lines are not used (thrown away). There is also special interlaced output modes, called PsF, both for NTSC and PAL, where both interlaced Field A and Field B are taken from the same full frame progressive output from the image sensor. With these modes, there is no time or motion displacement between the two fields so the images are clear for frame by frame viewing and/or capturing/recording using "Frame Capture" capture devices and/or DVRs. This concept is especially hard to understand (and explain!) as even my Sales managers have a hard time grasping the concepts. Terms such as "Frame" and "Field" take on different meanings between interlaced image sensors and processing versus progressive image sensors and processing. HD and Full HD, by using progressive sensors, processing, and digital output, have done away with this confusion... I hope this helps you. Let me know if you have any follow up questions. One important item I should add is that the output of the camera blocks is NOT necessarily the final output of the IP camera system that uses the blocks. An OEM's driver can use or discard all of the frames from the camera block to suit their desired application.
Steve have ? for you
How does Hitachi measure lux level on IP cameras
Please be specific
IPVMU Certified | 11/18/13 08:47pm
Hi Alex, our factory is (painfully!) conservative. As you may know, and what IPVM has been stating, there are no industry standards for stating the various video camera "specificatiions", such as Minimum Sensitivity. Our factory specifies Minimum Sensitivity at full frame rate (No DSS), Full Iris Opening, and default AGC Gain (which is not the maximum available AGC Gain), at a video output level of 50-IRE (or IRE Equivalent). This 50% video output level is a bit conservative; I see some "specifications" listed at 30-IRE (or equivalent). Rating a camera block at 30-IRE (or even lower!) provides a better (about 40% lower value) minumum sensitivity than rating at 50-IRE. Another issue, again brought up by IPVM, is the WDR "specification". This WDR "spec" is even worse... I hear people state a WDR "spec" of 100-dB (or even higher). I just smile and repeat to myself - OK, that would be the surface of the Sun to the Dark Side of the Moon (sorry, I love Pink Floyd!). Anyhow, I then ask the person, Can you please tell me what you are basing the comparison to?... God I hate "specsmanship"!!! Oh well, it is just part of the industry. By the way, since there is no industry standard for measuring and quantifying WDR performance, our factory does not provide a WDR "spec", even though our OEMs are crying for one. I tell them, 'make one up', just be sure to describe the conditions and criteria you are using for your "spec".
IPVMU Certified | 11/18/13 08:49pm
The best process for choosing among several camera systems is to perform direct comparisons - using the same conditions and criteria for each system. This is where IPVM and it's shootouts becomes so valuable for the industry.