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What is a 500W HD camera and how can it be 500 million pixels?
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edy:
I was asked to review a product that has a few interesting "specs" which seem to contradict each other and I need some help decyphering it. I can't give too many details yet, but basically one advertisement says it has 500 million pixels, and yet on another video it says 500W HD camera. So what gives?

Doing a quick Google search I noted that "500W" shows up a lot with (1080p) written next to it. What does the 500W mean, as I'm not familiar with this term with respect to camera resolutions. My understanding is that 1080p refers to 1920 x 1080, which is an HD resolution of roughly 2 MegaPixels (2 million pixels). It is NOT 4K, although I've seen some ads even say cameras with 500W-4K.

Certainly the "W" does not mean width, and I can't seem to find any reason why "500" would have anything to do with 1920x1080, or with megapixels. And the "W" can't be referring to Watts either.  :-//

Now with respect to the 500 million pixels reference, I think that's total bull$#!t. A camera with 500,000,000 pixels would have to have a 16:9 resolution of about 29814 x 16771 = 500,010,594. It may be that they are "capturing" a scene and stitching the images together to a maximum stitched image of that 500 MP resolution and they are using misleading marketing.

Another question I had was that when they talk about a 1000 x 1000 pixel camera (for example) the images that come out of that camera are 1000 x 1000 pixels in COLOR. Does that mean that for each color pixel, there are actually 4 sensing elements in the sensor (usually with color masks on top... 1 blue, 1 red and 2 greens). So could a manufacturer try to inflate the number of pixels by referring to the actual CCD sensing elements? Would a 1080p camera, which outputs COLOR images of 1920x1080 resolution, ACTUALLY HAVE a CCD which is 2x the width and height due to the additional color masks - each pixel being a 2x2 array of underlying monochrome sensing pixels beneath color masks)?

BrokenYugo:
Sounds like Chinese bullshittery to me, a quick Google of "500W HD camera" confirms it.
Siwastaja:
You are overthinking this.

A company with proper, actual technology will explain the terms they invent.

This is just some con artist putting random numbers and letters together. Like 10000W PMPO boomboxes in 1990's. They come with some gibberish and then they copy each other. Next thing is, someone upgrades their competition to 750W HD camera.

Regarding your question about 1000x1000 pixel color camera, in the typical/normal/default case, this only means 1000x1000 monochrome pixels coated with a so called Bayer filter in which 50% of the pixels sense green, and 25% and 25% sense red and blue. The gaps in color channels are interpolated in camera software (firmware, or when shooting "raw" files, this can be done later). These interpolation algoritms are nowadays much better than just linearly filling in the gaps. After all, you have actual image information at each pixel site, just in "wrong color", but an advanced algorithm can get quite close to the ideal/imaginary case where the same site would capture all three colors, by utilizing the fact that real world often consists of dull colors with lot of correlation between color channels.

This is the widely accepted way of specifying number of pixels, you just need to know this, you are not getting 3x1000x1000 actual pixels, but quite close to it in general purpose imaging. But if you are shooting a scene in deep red lighting which only registers in red pixels, you are going to notice significant reduction in resolution because the camera has only 25% of pixels to work with.

In earlier broadcast video cameras (don't know the situation as it is today), it was common to optically split the image to three separate monochrome CCDs. When they got the registration exactly right, these systems really did have each pixel site registering all three color. I bet this is quite rare today as CCDs (or CMOS sensors, more often now!) can be just manufactured to have ridiculously high number of pixels, like 20 million. The resolution is huge even if you need to interpolate colors. It would be nearly impossible to split beams and register three separate CCDs to that accuracy.
edy:
Here is a typical example of the "500W HD" Google search result:

https://www.walmart.ca/en/ip/500w-HD-Wifi-Endoscope-Camera-1920P-Flexible-IP67-Waterproof-Inspection-6LEDs-Adjustable-Borescope-Camera-2-meters-hard-line/2JREZVK5UCLB

Nowhere in the specifications for the above Walmart camera do we have any hint of what 500W refers to:


--- Quote ---Product Category:Portable camera

Lens Diameter: 5.5 mm
Camera light source: 6 adjustable LED S
Working temperature: 32 to 113 degrees Fahrenheit (0-45 degrees)
Battery: 1800mA Lithium Battery
Working hours: 1.5H
Power input: DC 5V 500 mAh/1A
Waterproof: IP67 (for lens only)
Focal length: 5cm~ infinity
Camera resolution: 2560*1920
Sensor pixels: 5 million pixels
Perspective: 70 degrees
Support system: IOS Android
Photo format: MJPEG
Video format: MP4
--- End quote ---

And here's an Alibaba camera that has 500W written in the description somewhere:

https://www.alibaba.com/product-detail/4k-Mini-OV5640-Sensor-Full-HD_1600294725966.html

*IF* and when I get the product to review I'll let you all know. For now these review requests are typically bait-and-switch or scam marketing so we'll see. I give them my work address and make sure they pay for all duty/tax/import fees otherwise I won't pick it up, and if they want it back they'd need to supply return postage paid labels and packaging or it's going potentially into the teardown video channel after. 
Siwastaja:
These are just cheap toys. Typically they kind-of work, but that's about it. If you just want any camera capable of storing some kind of image/video at whatever potato quality, buy one. It's very likely the image sensor isn't even full-HD, it's normal for such cheap toys to employ lower resolution sensors then just upscale in software (which only makes the files bigger, and saving them slower).

Clearly that 500W is now some fairly new trend term that just indicates cheap toy camera. They copy each other so it's not surprising they are suddenly everywhere. Soon they'll come up with something else.
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