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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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3answers
133 views

What are similarities and differences between raw editing and film developing capabilities?

Raw images are supposed to be detailed output from the camera sensor(s), with more details that what can actually be printed or displayed on a screen. Effects like exposure compensation or white ...
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2answers
73 views

Why does frame stacking alter colours?

I apologise in advance for the subject matter of my photos. I've not tidied the table for a few days. I needed indoor artificial lighting for the long duration of this experiment. Both images are ...
4
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1answer
46 views

How to minimise the noise in colour values when moving between colour spaces?

Let's say I was to change from RGB to HSV using a software like Matlab and then convert the result back to RGB using the same software. I know that there are going to be some slight noise and error in ...
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2answers
62 views

What is the difference between HSV and CIE-Lab color space?

When do we (or should we) use HSV color space and when do we use CIE-Lab color space?
9
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5answers
4k 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.
3
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1answer
133 views

Can I extend dynamic range by underexposing and then downsampling (“binning”) my images?

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). ...
57
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15answers
42k 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
322 views

What are the anomalies in this picture of earth?

I was playing around with the New NASA pic of earth (posted July 20th 2015 on Nasa Goddard space flight center on Flickr). I've found this very odd structure on the bottom right corner that is pretty ...
2
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3answers
129 views

What education or certifications are needed to get work as an image processor or photo retoucher?

I am thinking about seeking employment in the area of photo retouching and image processing. What education or certifications would be good to help make this happen? And what online resources are ...
3
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3answers
312 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 ...
12
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3answers
16k views

Is it possible to make a single still photo from a video?

The idea comes from the fact that in astronomy (amatorial), it's common to take videos from a telescope with a webcam and convert them into a single, less noisy picture. The principle is that of ...
5
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3answers
8k views

What software tool can I use to convert a photo to line drawing?

What's the best way to do this, using free software? I want to convert photos to line-drawings, maybe cartoons ...
0
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2answers
347 views

How can I batch process HDR images in Lightroom?

I have taken a series of 8 images for a 360 panoramic shot using bracketed exposure of 3. This produces 24 total images, which I would like to process in lightroom using HDR merge. Currently, I am ...
0
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1answer
111 views

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 ...
9
votes
2answers
263 views

What algorithm can I use to simulate bokeh?

I am attempting to write a script that loops through each pixel in a photograph and applies a bokeh to the image as a whole. I built a script based off this link, however that seems to be a hack. I ...
2
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1answer
280 views

Is there a technique for combining multiple images to create a sharper result?

I've been experimenting with photogrammetry for a while, and the main hurdle I keep tripping over is the clarity (lack thereof) of my images. Rather than spend a lot of money on a better camera, I'm ...
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1answer
87 views

how can to convert single spherical distort image to rectangle image?

how can to convert single spherical distort image to rectangle image? I looked for more than a week I did not find the solution please help me.
5
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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 ...
6
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2answers
172 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 ...
0
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1answer
130 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 ...
2
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3answers
145 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 ? - ? ...
11
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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
120 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
151 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 ...
3
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3answers
289 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
127 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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1answer
111 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 ...
3
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2answers
263 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
246 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 ...
2
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3answers
707 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
votes
2answers
262 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
93 views
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0answers
70 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
117 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. ...
0
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1answer
46 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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0answers
138 views
4
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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
212 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 ...
3
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2answers
119 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
99 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 ...
6
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4answers
21k 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
votes
2answers
251 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 ...
4
votes
4answers
627 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
votes
4answers
815 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 ...
13
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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 ...
26
votes
4answers
878 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. ...
18
votes
8answers
35k 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 ...
2
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1answer
215 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 ...
0
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1answer
52 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 ...