Hikvision DS-2CD2032-I 3Mpix bullet - Is it really 3Mpix?

[teemto 0]

Hello everybody!

 

I just got a nice small Hik DS-2CD2032-I 3Mpix bullet camera on my bench.

The camera itself is very nice and performing more or less as expected.

 

But.....

Are You guys sure, that there is true 3Mpix sensor inside?

 

See the attached picture. The upper screenshot is taken with max 2048x1536 3Mpix resolution. The lower one is FullHD 1920x1080 2Mpix.

 

Now please have look to the flower on the right side. On the lower picture - which is 1920 pixels wide You can see whole flower and almost all the table. So on the upper 3Mpix picture, 2048 pixels wide (it is 128 pixels more) I expected to see even more of the table, and of course the flower. And what You see on the upper picture: only half of the flower. The angle of view is smaller, than expected.

 

Now see the frames on the lower pic. The blue one represents the expected 2048x1536 field of view.

The red one is the real field of view (in 3Mpix mode), and it is a very close approach to a 1600x1200 resolution. It seems to me, that the 3 Mpix video stream from this camera is an software upscaled 2Mpix 1600x1200. So - is the true resolution of the sensor really 3Mpix?

 

What do You think?

 

[finalwish 0]

MaxIcon did a good comparison write up for this.

See viewtopic.php?f=19&t=35752.

[Digiscan 0]

MaxIcon did a good comparison write up for this.

See viewtopic.php?f=19&t=35752.

Great link.

 

Hikvision does say the FOV is less side on 3 MP. The 2 MP setting gives an appreciably wider field of view, but it's also shorter.

 

For what it's worth I went back and forth with my camera and comparing cropped, zoomed-in sections of a picture the clarity when set to 3 MP is noticeably better than the clarity when set to 2 MP.

[MaxIcon 0]

Part of the reason the clarity is better is because the pixels per foot is higher at 3MP, due to both more pixels and a smaller FOV. Most 3MP cams give the same PPF in either 2MP or 3MP, but have a wider FOV in 3MP.

 

This indicates that their sampling algorithm does a good job, though I've seem some artifacts on night shots that show up on 3MP but not 2MP. It's hard to say what's happening at the sensor level, though.

[teemto 0]

MaxIcon - You did a great job. I was just looking around to find our lost-somewhere-test-chart and perform some visual tests on the camera, but You did it before and Your results are exactly as I expected.

 

So it seems, I'm not the only one who says "there is no spoon" when talking about real 3Mpix in this camera.

Thank You for help and confirmation of what I suspected.

 

PS

I sent an inquiry to Hik asking for a specification of the sensor....

[buellwinkle 0]

There's confusion between number of pixels and resolution and camera companies love using pixels, after all, why differentiate between a $99 16MP digital camera and a $999 16MP camera, same right but resolution between the two can vary by a lot.

 

I did verify resolution on a chart compared to other 3MP cameras I had including Dahua and ACTi and the resolution was comparable at 3MP and did drop when put in 1080P mode. People think that going to higher MP cameras, like 5MP makes for 2/3rds more pixels and that's true, but not 2/3rd more resolution and from what I've seen, I would guess at maybe half that, about 1/3rd better resolution. At night it's much, much worse where I've seen 1080P cameras that were marginally better than 720P cameras in resolution because of the additional noise from higher density sensors.

[teemto 0]

There's confusion between number of pixels and resolution and camera companies love using pixels, after all, why differentiate between a $99 16MP digital camera and a $999 16MP camera, same right but resolution between the two can vary by a lot.

 

You are absolutely right. But it was not the subject of my small research.

To be precise - the camera itself is not bad. It has very good price/quality factor.

And the only reason for me to look for the real data of the inside electronics is that

1.I like to be precise when offering something to my customers.

2.It is always better to know what's under the hood....

[teemto 0]

I have the answer from the distributor. They say, that the sensor installed in the DS-2CD2032-I 3 megapixel camera is the Aptina AR0330 2304x1536, 1/3", 5.07mm(H)x3.38mm(V).

 

The 3Mpix 4:3 stream uses physical 2048x1536 pixels (2048 out of 2304 horizontal).

The 2Mpix 16:9 uses physical 2304x1296 (scaled 20% down to 1920x1080).

 

So according to the official info it is the 3,5 Mpix camera.

 

I think, I have to find this lost-somewhere-test-chart and try to verify this, although the results may be not clear - the camera has very simple, small lens and this affects high resolutions in siginificant way.

[buellwinkle 0]

Thanks for clarifying that, a source of confusion since the camera came out. Like I said, using a standard chart, I saw no difference in optical resolution between this 3MP and other ones I had laying around, if anything, the Hik was slightly better.

[MaxIcon 0]

That sounds reasonable, and matches the FOV shift.

 

Using measured HFOV on the Hik 2032 with the 4mm lens:

3MP = 69 degrees H (89% of the 1080p FOV); 2048/2304 = 89%

1080P = 77 degrees H (112% of the 3MP FOV); 2304/2048 = 113%

 

That's been my stance all along; one resolution or the other was scaled instead of directly sampled. It's good to know which.

 

I also did resolution chart measurements, and the results were also inconclusive, so their sampling algorithm is good.