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Image processing is the computational transformation of an image signal. It's about the technical side of batch transformations, conversions, and enhancements, as distinct from post-processing (adjusting an image to achieve a desired look, probably using image processing).

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What causes chroma noise in an image sensor

I'm trying to understand what is causing chroma noise in an image sensor, specifically why it is so visible when the ISO is set to a very high value (which for CMOS I guess means that there is an ...
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3answers
2k views

How can I adjust the colour temperature of an image programmatically?

I'm wondering how to convert programmatically (i.e. with a programming language rather than an editor) from one colour temperature to another? If, for example, I make the assumption (and it's a big ...
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2answers
159 views

How does a camera artificially decrease DoF of a shot from a single position?

Some cameras with small sensors can artificially blur image background provided there's an object in the foreground. FujiFilm calls it Pro Focus filter. I'm not sure if the camera makes one or two ...
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1answer
85 views

Access “Pre-Bayer” RAW image to analyse channel values [closed]

First of all i 'm working with a Fuji Finepix HS50 EXR I'm doing an internship and my job is to collect photosite raw data to analyse phosphorescent paint comportment. To do so I need to access the ...
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3answers
236 views

How to open a raw file in Camera Raw full size rather than cropped to in-camera aspect ratio?

On a recent photography holiday I took a number of photographs using the in camera option to change the image size to, for example, 16 x 9. The native image size of the camera is 4:3. I transferred ...
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1answer
61 views

Getting more signal from downsampling/binning

In microscopy we often can sacrifice spatial resolution to collect more photons per pixel. Using sCMOS sensor and binning by factor of 2, we can get bump (up to 4x) in our signal-to-noise ratio (SNR). ...
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3answers
109 views

What are the exact pixel values (or ranges) for shadows/midtones/highlights in Lightroom?

In lightroom, different sliders impact different pixel intensities. I'm looking for the exact values (or approximate ranges) of the various levels: blacks: 0 - ? shadows: ? - ? midtones ? - ? ...
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3answers
2k views

Can I combine several low quality pics into one higher quality picture?

Is there an easy tool to combine low quality pics taken from a mobile phone, all of the same thing but taken within a few seconds interval from one another, mostly suffering from slight out of focus ...
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2answers
102 views

How can I convert a photo to a fixed palette with pre-defined weighted color proportions?

I am creating a physical mosaic from a photograph, where each mosaic tile will correspond to a pixel of the (scaled down) original picture. The problem is: my tile color selection is limited, with the ...
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2answers
71 views

How is data in a camera's colorspace transformed into XYZ or a standard RGB space?

I have a canon 600d that says it uses sRGB. How is this even possible without having the same spectral sensitivity spectrum as a standard observer? It is possible to define the matching functions of ...
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3answers
212 views

How can one correct intensity flicker due to AC line frequency?

Is there a good image processing method to get rid of the horizontal stripes in the images taken under fluorescent lighting? These stripes (flicker) occur when you take pictures indoors due to the 50 ...
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0answers
34 views

An online service to create “photo stacks”? [duplicate]

I'm really not sure what the following is called (this isn't my image): The image was from here (not really relevant though). I want to create something like it, though. Is there a website for me to ...
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1answer
99 views

Does shrinking the upscaled picture improve its quality (in terms of blur)?

Take a look at the following diagrams: The original picture: The upscaled (2x, bilinear) picture: In both cases the first item in the first row is the input image. There is its 2d fft next to ...
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14answers
37k views

What tools are available for RAW image processing in Linux?

I have been taking photographs with RAW format. What tools are available for working with RAW under Linux?
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1answer
101 views

can you remove a hair on the image sensor in light room?

i took a series of pictures yesterday and discovered that shooting around f/13, f/16, there is what appears to be a hair located on the image sensor and is visible in the pictures where the lens is ...
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4answers
3k views

What software should I use for converting fisheye photos to normal rectilinear photos?

Can you recommand me a software for doing this job? I shoot using Sigma 8mm lens and I would like to be able to obtain a normal image out of that. The camera is canon 550D.
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2answers
197 views

How can I detect upscaled photos?

I have a collection of JPEG photos, each 500 to 600 pixels on the longest side. How can I detect which ones have been algorithmically enlarged from a substantially smaller photo? An online ...
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2answers
135 views

What workflow will speed up sorting photos stored on a NAS in OS X finder before import into Lightroom?

I have a DSLR camera; D7100 to be exact. I originally purchased it, because I was fed up with all the point and shoot cameras out there and wanted control over my photos. At this point, I'm wanting ...
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3answers
543 views

What is Lightroom *really* doing when I change a Camera Calibration?

What does LR / ACR really do when a user changes the Camera Calibration setting? Here's Adobe's statement (for LR4, but I didn't find a newer one and there's no reason for this to change): Lightroom ...
7
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2answers
236 views

Does it matter what edge finding algorithm you use?

I was playing around with an action set that I have that creates edge masks using the Roberts, Robinson, Sobel, Prewitt, and Kirsh algorithms. Because of the differing levels of brightness, I decided ...
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1answer
88 views
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0answers
62 views

In intuitive explanation what is zig zag scanning?

In intuitive explanation what is zig zag scanning and what is the purpose for using it in image processing ?
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3answers
102 views

Utilities for comparing different JPEG compression engines?

I'm looking to do some statistical analysis on the effect on an image of various compression systems, with the end-goal of hopefully being able to determine which is a recompressed version of which. ...
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1answer
41 views

Retina Display-Can anyone suggest how to literally make an image “retina display”? [closed]

Can anyone suggest how to literally make an image "retina display"? I think it doesn't depends on the camera. Does their is any software for it? I want another suggestion. Can anyone suggest a ...
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96 views
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5answers
18k views

What is the difference between Adobe Photoshop and Lightroom?

I have been using Adobe Photoshop for years. I even use Illustrator for vector work from time to time. Then along came Adobe bridge and it seems to be an attempt at a better way to browse, sort, and ...
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4answers
198 views

Seeking a way for “authoritiative”, proven method to prove that two photo images are “nearly identical”?

In usual discourse, when looking at an photographed image (A) - which is a JPG - and a slightly photoshopped version of it (A2), most people can intuitively compare the two and visually assess that ...
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2answers
116 views

How can I give an assitant rights to edit without having the possibility to download the image? [closed]

The situation is this one: we are a small photo company. We have a few people going out to shoot various assignments. When they return they hand me the memory cards and I download the images into the ...
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3answers
86 views

Convolution algebra and capture, creative, and output sharpening

I'm making the reasonable assumption that software implements sharpening via convolutions. Convolutions are both commutative and associative. So... why do we talk about capture sharpening, local ...
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4answers
17k views

How to batch process images retaining them as PNG in Photoshop?

I need to optimize 700 images in PNG in a batch process, but Photoshop only gives me the option to optimize the images and export them to JPG, when I want to mantain the images on PNG. Is there a way ...
2
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2answers
203 views

What is subpixel sharpening?

What does sub pixel radius sharpening mean in this review of the Pentax K5IIs mean?How does it differ from regular sharpening? Now this is the same raw file, with a 301% .3 sub pixel radius ...
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4answers
586 views

What algorithms or example tools are there for denoising of images in Raw format?

I am trying to perform some post-processing of Camera Raw images captrued using my Canon EOS 450-D. I am using PS CS5 and GIMP particulary to remove noise which is present in images. My questions is: ...
4
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4answers
719 views

Query about gamma correction?

I have a bespoke Image Capture & processing flow, wherein I do the following operations:- Capture Raw data-->De-Bayer(Get RGB)-->Color Balance-->RGB-to-YCbCr-->Image sharpening-->Denoise ...
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2answers
2k views

Is it possible to print a photo so it can be mounted on a globe?

I'd like to transform an image so that it can be mounted on a sphere. I'd like to use an image of a map (see the One Piece world map on the image), but it could be anything. Here is a kind of Family ...
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4answers
809 views

What are Color Profiles and where would I find information on using them properly?

I see the term "Color Profile" a lot and I have this vague idea that it helps you adjust color values based on the unique differences of both cameras, displays and printers from some ideal device. ...
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8answers
32k views

Where can I get free RAW files online for practicing with Lightroom?

I've downloaded Adobe Lightroom in order to learn RAW image processing. I want to practise on some photos that covers basic subjects (Histograms, HDR etc). Is there a good, free source of RAW images ...
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1answer
196 views

How can I export 16 bit tiffs with Mac OSX' imageing engine sips?

I'm playing around with Apple sips command. When I export a Canon raw file (CR2) to tiff via sips -s format tiff -out img.tiff img.cr2 the result is an 8-bit tiff, although the CR2 source is ...
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1answer
45 views

Programming curves tool how to work with RGB (combined) channel

I'm working on a Curves tool and i need to adjust all three channels at once using one curve. (RGB Curve) Internally, the class i created for the counting gets a set of control points the curve ...
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2answers
182 views

What, technically, is happening when one adjusts the 'Exposure' setting in a raw editor?

Since the photograph has already been taken by the time it is being edited, 'adjusting the exposure' of a RAW file must have a specific technical meaning (which I have struggled to find) Can someone ...
3
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1answer
228 views

RGB colour correction of CCD camera images [closed]

I've developed an application which is able to communicate directly with a CCD camera (unbranded and obscure) and I'm able to capture and store the image from this camera. When the image is first ...
4
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3answers
146 views

Superimposing photos and thermographic images

I have two cameras: one is a "visible" camera and the other one is a thermographic camera, which, as many of you may know, it is a camera that captures infrared radiation instead of visible light. I ...
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0answers
133 views

How can I automatically square-crop an image?

I have a large number of photos that I need cropped into squares, the thing is I want to crop them "intelligently" so I don't end up cropping through someone's face if tha isn't necessary. Are ...
0
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1answer
270 views

How can I differentiate an Original and Photoshop Image [duplicate]

May be this is a wrong place to question this. But, please allow me to ask at least. We have some photography event in our office. So, we have mentioned the rule of date capture (like photo must be ...
0
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1answer
243 views

What is the best way to resize a high-DPI image for use on the web and in mobile apps? [duplicate]

I've been given an image (I'm guessing straight from a camera) and it's currently at at 240 pixels per inch. It's been a while since I did much Photoshop; I have three questions for two requirements: ...
5
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3answers
2k views

Easiest way to auto-align a stack of images? [duplicate]

I am working on my own "everyday face" project - taking pictures of myself to combine them in a sequence afterwards. I'm wondering what is the easiest and fastest way to align all pictures so my ...
7
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2answers
4k views

What workflow should I use for processing RAW photos in Lightroom?

I started shooting in RAW, and I use Adobe Lightroom. What workflow would you recommend to use for the processing? I will really appreciate a detailed description of the steps (or a link to one). ...
2
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1answer
124 views

Recommended settings in Lightroom 5 when exporting to NIK / other plugs as TIFF?

When exporting to NIK or any other plug, Lightroom asks for some information. AFAIK, and the more I study the less I know, the exported file should be a TIFF (no good options there), ProPhoto RGB ...
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3answers
175 views

Can you take a picture of a faded docket and see the details again in computer?

Hi I have a very faded docket, where I can still read the details with bare eyes, but when I tried to photocopy and scan it, it just gave me a white docket. My last hope is using a camera. Please tell ...
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3answers
86 views

How to erase ALL metadata associated with an image? [duplicate]

I'm looking for a way to get rid of ALL metadata associated with an image. What should I do?
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1answer
72 views

Image bending? Light bending? [closed]

Anyone know how to project an image onto a curved wall but still make the image appear as though its on a flat surface?