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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
78 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
34 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
64 views

What is the difference between edge detection, Sobel detection, and Canny detection?

What is the difference between edge detection, Sobel detection, and Canny detection
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2answers
113 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 ...
6
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1answer
168 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 ...
3
votes
1answer
94 views

How to open a raw file in camera raw in the correct image aspect

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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3answers
65 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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1answer
50 views

Weighted conversion to a fixed palette

for some reason I need to convert a picture to a 16-color palette. While the conversion itself is nothing special, I need the final result to stick to a well-defined color proportion. This means, for ...
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2answers
140 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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2answers
210 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 ...
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4answers
181 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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1answer
35 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
178 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
196 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
votes
3answers
124 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
97 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 ...
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1answer
194 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
138 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: ...
3
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3answers
634 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 ...
2
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1answer
106 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 ...
0
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3answers
168 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 ...
0
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3answers
74 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
54 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?
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1answer
87 views

2 Images, same object: tone difference and alignment [duplicate]

I would like to know a software which helps in post-production to calculate the general color/tone difference of 2 images. The images contain the same object, but arn't shot from the same position. ...
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0answers
27 views

Erase background from an image [duplicate]

I 'm interested about erasing backgroung from an image. Taking into account that I 'm an amateur, which is the best way doing this? I hade already tried with backgroung eraser tool ...
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2answers
92 views

Flat fielding an image with two 1-D arrays

This is more of a math questions, but I thought I had a better chance of finding a camera enthusiast with a math background here. I've always flat fielded images using a two dimensional array with a ...
1
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1answer
113 views

Long Exposure Photo vs. Video [duplicate]

If I want to make some cool photos with long exposure times but not having a good camera that allows me to define the time, can I get the same result recording a video and make the superposition of ...
1
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3answers
325 views

How does the spectral sensitivity of different sensors affect the resulting photo?

I am learning about light and color formation but I don't understand how does the sensitivity affects an image. Take for instance the different sensitivities for two "cameras" for each RGB channel ...
0
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1answer
70 views

Slicing articles from a photo or pdf newspaper page [closed]

I have a pdf file which is a pdf format of a newspaper page that has many articles(image + text), same as the articles we find in the newspaper that newspaper vendor drops at our place everyday. I ...
0
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1answer
109 views

What's the best way to remove discolouration of scanned photographs?

I'm got a batch of printed photos which I am scanning to store a digital copy of and possibly enlarge them for printing. I've scanned them at the maximum quality (600DPI) and saved it with the least ...
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1answer
147 views

How can I change the pixel data in a DNG while keeping all the metadata?

I am looking for some free tools that will let me easily process the pixel data in a RAW file (DNG or NEF) while keeping the metadata untouched. Are there any such tools? Use case: I am ...
5
votes
3answers
226 views

Creating one photo with multiple rows as if one is head-on to each row?

I took a picture of a crescent arch with scaffolding (apparently for maintenance) but can't post it for lack of "10 reputation." However the effect is simple, in that from the vantage point, the row ...
2
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1answer
78 views

Are there any good “dispersion blur” image filters?

I would like to obtain an effect where pixels get spreaded locally. I tried to reproduce how such a filter would look, I hope you get the idea: before: after: Note: here I ran a blur, aded ...
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3answers
3k views

Is there any good method to invert a negative image (duplicated with a digital camera) in Lightroom?

I made some duplicates picture (of negatives) with my digital camera using a bellows and a repro-dia. The image is obviously in a negative format but in RAW. Is the invertion function exists in ...
2
votes
1answer
121 views

How to safely and efficiently remove frames of photo added by software?

How to safely and efficiently remove frames of photo added by software? I'm NOT talking about the physical frame, but the border/frame added by software such as PhotoShop. I'm particularly ...
2
votes
1answer
77 views

Is the 'mono' setting in smartphone cameras a form of grayscale?

In the description, my smartphone camera describes the 'mono' setting as being black and white, but it appears more to be grayscale - am I right in this assumption? Also, if it is grayscale, how is ...
3
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2answers
773 views

What does “frequency” mean in an image?

I don't understand how frequencies are defined in images/photographs. As far as I understand it now, high frequencies are like sharp things in images, like edges or so, and low frequencies are kind of ...
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2answers
220 views

What factors, asides from temperature, affect dark current?

What is an effective means of determining the average dark current/noise of a camera image sensor? My understanding is that this is type of noise is temperature dependent, what other factors may ...
2
votes
1answer
173 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 ...
4
votes
1answer
956 views

Can I convert raw files to TIFFs via the command line using Apple's converting engine?

I want to convert from the command line a bunch of RAW files into tiffs using the same converting engine as Apple's Aperture or Preview (in order to get the same results as from these applications). ...
2
votes
1answer
432 views

If I want soft focus, should I get the Canon 135mm soft focus lens or do it in Photoshop?

I always read that when possible it's best to "get things right in camera" which I always aim for - so following that line of thinking, would it be worthwhile to get the Canon 135mm f/2.8 soft focus ...
4
votes
3answers
2k views

Is “Active D-Lighting, NR” a necessary evil?

Are the settings "Active D-Lighting, NR" in Nikon DSLR necessary evil or should this be turned off (managed through image editor)? What is the effect of this setting on processing time and battery ...
2
votes
1answer
328 views

Gamma loaders on Windows 7/8: necessary or not?

I noticed that some monitor profiling software (like X-Rite i1 Display Pro, for one example) install their startup gamma loaders under Windows 7. Back in the XP days we used those utilities to load ...
9
votes
4answers
6k views

Why is a physical anti-aliasing filter still needed on modern DSLRs?

I understand the purpose of the anti-aliasing (AA) filter is to prevent moire. When digital cameras first emerged an AA filter was necessary to creat enough blur to prevent moire patterns. At that ...
0
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3answers
322 views

Would you use an online RAW image processing application? [closed]

I'm just curious, if there was a web-site/web-portal related to RAW image processing what features you would prefer to use on it: RAW image processing (from different Cameras) Implementing different ...
8
votes
2answers
798 views

How can I “focus peak” a photograph?

Does an application exist where I can input an image and then the application indicates what parts of the image are in focus? I imagine it as a sort of post-process focus peaking.
5
votes
4answers
12k 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 ...
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votes
1answer
1k views

How to calculate object's height in pixels from an image? [duplicate]

Possible Duplicate: Calculate object size when I have physical pixel size I am working on the following formula to calculate distance of object from camera: distance to object (mm) = ...
0
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2answers
403 views

Image overlay and processing [closed]

If I overlay an image( lets say A) with another image(B) using 50% transparency. is it possible to recover A without knowing what B is? Dose overlaying make it hard to extract the original content? ...
3
votes
3answers
1k views

Why do I have to convert RAW files to JPEG to open them? [duplicate]

Possible Duplicate: How do I get started with RAW photography? I am a new to RAW shooting and recently bought a Nikon DSLR. I find that only the software which came with the camera can open ...