I'm writing to someone to say something along the lines of: "May I see that image in a higher resolution; there is some important text and/or finer details that are unintentionally pixelated/obscured due to..", but it has to be eloquent, intelligent and in a formal, technical/academic style.

I think I lack the appropriate lexicon for this specialized field (graphics, imaging, etc).

Particularly the part about how a bitmapped or raster image pixelates or distorts due to insufficient resolution or (relatively) supersufficient digital-zoom ratio. Is there some specific terminology for this condition or occurance?

When dealing with traditional, analog-style optics (i.e. light microscopy), there's a comparable phenomenon, referred to by engineers & physicists as the diffraction limit.

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    The academic field to look for is "signal processing". Isn't pixelation a form of aliasing? – Jongware Jun 22 '18 at 10:25
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    @usr2564301 sort of showing pixels is not aliasing, since the image is most likely anti-aliased, as such it is just under sampling... but i could call the effect it interpolation – joojaa Jun 22 '18 at 11:12
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    @joojaa: it is (close to) signal aliasing, as analog input is converted into discrete squares. But maybe I am overthinking it and the word OP is looking for simply is "resolution" (i.e. "a lack of sufficiently high ~"). – Jongware Jun 22 '18 at 11:53
  • @usr2564301 - I think you might be right, but it's the OP who is over thinking it. "insufficient resolution" is another option. – Billy Kerr Jun 22 '18 at 12:44
  • @usr2564301 well it can be aliasing if the reconstruction filter is for example a box and the zoom factor is not a integer value. However maybe a better tern would be upsampling? – joojaa Jun 22 '18 at 12:47

In terms of distortion, often images can be subject to compression artifacts (or JPEG artifacts), which occur as a result of the compression algorithm used for JPEG files.

This doesn't really sound like this is your problem though; it sounds like you are having problems with low resolution, which is a sufficient term for your situation.

  • Since a image artifact is a unintended glitch, other uses are rendering artifact which might fit the bill. But also possibly scaling artifact. – joojaa Jun 22 '18 at 19:12

You can choose between... Pixelation and resolution... and yeap, those are technical terms.

obscured due to insufficient resolution or (relatively) super-sufficient digital-zoom ratio

That sounds nice.

The diffraction limit. is a physical phenomenon also present in digital images, as you said to some optical limitations on the lens, it is not by an analog substrate receiving the image, but how it is produced. So it could be also present in a digital photo.

"Diffraction limit" could be present by using a low aperture, for example, an f22 on some type of lenses.

There could also be some limitations on the quality of the lens itself producing less resolution than the digital sensor can receive, by either producing some aberrations or simply by lack of focus.

When these flaws are introduced "artificially" on an already produced photo, normally are generated by a resampling of the image.

You have two options, either resampling by just copying information from adjacent pixels (nearest neighbor) or by interpolating the information to smooth the jagged borders produced by the former.

A digital zoom takes the information of the image and tries to interpolate it to smooth the information when enlarging it. But there is not much you can do about it but try to apply some sharpening (or deblur) algorithm. http://smartdeblur.net/

If you are not enlarging the image, you are reducing it. In that case, yes, you simply have a lower resolution image, and you can ask for a higher resolution one.

Another type of blur can be artificially added, like some gaussian blur, and or pixelation, to intentionally obscure some data.

But in your case, it seems that the only options are "pixelation" or "resolution".

  • Technically adding sharpening to the rescaling algorithm is the same as applying a sharper reconstruction filter. – joojaa Jun 22 '18 at 16:48

its called "aliasing". Technically that is the term, any time nyquist's rule is broken. Its broken thousands of times every time you see a lossy jpeg. its broken thousand of times every time a digital photograph is captured.

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