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Products => Thermal Imaging => Topic started by: xors01 on February 19, 2019, 08:14:41 pm

Title: Get wavelength values for every pixel
Post by: xors01 on February 19, 2019, 08:14:41 pm
Hi,

Recently I bought a thermal camera (DH-TPC-BF2120) with the purpose of building some software behind it and run my own analysis in a certain place.

However, once with the camera on my hands I'm unable to access the "raw" matrix file with the wavelength values for each pixel, getting the colored picture with the hotter and colder areas is fun but not so useful in my case, so I'm not sure if that's something to do with my inability got get it, with the model if it doesn't allow that or with the whole Dahua brand.

Any ideas?
Title: Re: Get wavelength values for every pixel
Post by: Vipitis on February 19, 2019, 08:41:04 pm
From the data sheet and product page, it looks like the camera is exactly what it is intend to be and nothing more. A low resolution security camera and not for any inspection purposes. You only get access to a upscaled video stream that gets compressed for streaming, no hint of raw data and not a word about radiometric access.

You also won't get any wavelength information out of a radiometric camera meant for inspection or research, you get a temperature for each pixel based on some calculations form the sensor response and it's own temperature etc. LWIR is a very broad spectrum because radiation gets lower in power the longer the wavelength. If you are interested in spectroscopy, or even (far)infrared spectroscope - you will need to spend a lot more money. Even low pass, high pass(cut-) filters for the LWIR spectrum cost a few hundred.

Good luck. It isn't unheard of badly designed firmware in network cameras that allow you to hack them(more like a network intrusion and less of a liberation of hidden features, but look into that for a chance).
Title: Re: Get wavelength values for every pixel
Post by: xors01 on February 22, 2019, 06:43:56 pm
Thanks a lot for your reply Vipitis, that actually made me think that a feasible chance could be to ask the brand directly and so did I.

They told me firmware modification on demand was possible, so I'm waiting for a quotation, but expensive as it might be it will always be cheaper than a new camera with that option enabled by default, so I'll just wait and see what their offer is. In the end the change is just a matter of removing the colour autoscale by a fixed one, with that I'll be able to calibrate it and use the thermal image to get the temperature per pixel.