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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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2answers
1k 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 ...
0
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2answers
258 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
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 ...
4
votes
1answer
1k 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
538 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
4k 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
368 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 ...
11
votes
4answers
7k 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
votes
3answers
337 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
941 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.
6
votes
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 ...
-1
votes
1answer
2k 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
votes
2answers
435 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 ...
2
votes
1answer
333 views

How can I control exposure via a smartphone API when lighting changes? [closed]

I'm trying to create a smartphone application on iOS/Android that uses image processing. I'm experiencing the following problem: when I am recording and a new object (mostly white) enters the ...
5
votes
5answers
383 views

Object size discrepancy in image (Round object occupies more pixels than it should)

I am photographing a sphere (a ball): in the same picture I have also placed a ruler. The ball and the ruler are in the same plane. i.e. the ruler is placed such that it is aligned with the center of ...
5
votes
1answer
949 views

Lightroom 4.1 HDR (From other source than Photoshop)

I'm trying to use the new feature of lightroom 4.1 that allows us to edit 32bits floating point tif directly within Lightroom. The workflow seems easy enough when you have Photoshop but I do not. I ...
4
votes
1answer
411 views

Understanding Hue, and is there something else I should be using?

I am trying to isolate objects of a certain color in an image. Looking at this image, you can see that I have extracted the hue channel, and have filtered these values so that the closer a pixel's hue ...
1
vote
2answers
269 views

some criteria when a filter looks good

I'm a developer who wants to figure out when a filter would look good applied to a given image. For example, I have sepia, solarisation and pencil filters. Okay, the perception will be very ...
18
votes
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 ...
3
votes
3answers
577 views

Photo Processing - What am I doing wrong?

I seem to have a problem processing photos and I am not sure where I am going wrong. The issue is on my desktop monitor the photos look great. Overall vivid color, brightness, contrast etc. When I ...
4
votes
1answer
1k views

Tablet Apps for Simple Processing of RAW files

What tablet Apps would you recommend for simple RAW processiong on a tablet? Currently using Samsung Tab 2, 7 inch tablet. My main concern is just open the RAW file and do some Cropping and upload ...
4
votes
1answer
137 views

Manipulating images at different spatial scales

Is there software which will allow manipulating an image at different spatial scales? For example, change the contrast or brightness of features smaller than 50 px but larger than 10 px. I have ...
9
votes
3answers
563 views

Is the image processor relevant in a camera when shooting RAW?

When cameras come out the company often states that the image processor is upgraded. Does such an upgrade matter when one only shoots in RAW? When shooting RAW the image is taken directly from the ...
12
votes
3answers
2k 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 noisier picture. The principle is that of ...
2
votes
1answer
151 views

Learning about photography algorithms [closed]

I'm very interested in learning about algorithms in photography (in particular processing photos). In addition to algorithms, I'm interested in learning about photo formats (probably RAW and jpeg the ...
11
votes
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 ...
6
votes
3answers
10k views

How to analyze images with Fast Fourier Transform method?

I am learning about analyzing images with the method of FFT(Fast Fourier Transform). The image I am analyzing is attached below: And the result of the FFT analysis of this picture is presented ...
2
votes
1answer
197 views

What is the the product of two Fast Fourier Transfoms?

I am reading a book about image processing. I have found mention of a method for processing images. It is said that a special effect could be reached when we multiply two results of the Fast Fourier ...
25
votes
2answers
3k views

How does exposure fusion work?

I understand that "exposure fusion" is a method for combining different exposures into a single image. How exactly does it work, and how is it related to HDR?
6
votes
3answers
1k views

What kind of process is this old photo in glass?

I have 2 old (circa 1800?) black and white photos sizes 9x11 inches in glass. It's a picture of a little girl in a flower field and another of a woman outside the home, sitting on a chair with her ...
2
votes
2answers
150 views

How does a glare arise in images?

I know am sounding dumb but i have not been able to find a correct definition of glare What are the reasons it props up into images For example am taking a photograph of a fruit in diffuse light : ...
0
votes
3answers
272 views

What settings do I have to use to take pictures like this one by S Dot B?

I am impressed by this photograph of hip hop artist Kid Ink by S Dot B photography: http://www.killerhiphop.com/wp-content/uploads/2011/03/Kid-Ink.jpg Can anybody tell me the settings for my Nikon ...
4
votes
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 ...
0
votes
4answers
910 views

A beginner with post processing wanting to learn [duplicate]

Possible Duplicate: Any good tutorials for learning how to post-process images? Though I have been trying hands on photography for quite a while now, I want to learn post processing of ...
6
votes
2answers
1k views

Is “saturation” an image-processing concept?

Image saturation is a concept used to describe the purity or intensity of color in an image, such that an image with very little saturation approaches a black and white image. Pink, then, is said to ...
1
vote
1answer
327 views

How can I extract qualitative information from EXIF files?

I have bunch of EXIF files. I am looking for some heuristics to extract qualitative information such as if the picture is portrait or not, if the picture was taken in day or night, if the picture is ...
13
votes
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 ...
3
votes
2answers
2k views

How to achieve misty look and vintage colors like Jaime Ibarra?

How are the color tones and the misty look achieved in the photo below? Does the technique/s have a name? (Note: link is NSFW.) Link to image - ...
9
votes
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.
3
votes
1answer
430 views

Which postcard mailing services are the best? [closed]

I have noticed several sites offering to let me upload a photo, some text and an address. They will then print a postcard with the image and my text and mail it for me. Some offer smartphone-apps and ...
0
votes
4answers
480 views

What color system best differentiates Yellow/Red/Black? [closed]

I'm working on a image processing system to segment three different types of pixels that are more or less Yellow/Red/Black. Now my question - which I though it's best to be asked here - is that which ...
4
votes
4answers
587 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: ...
6
votes
4answers
3k views

Should I save an image as png, jpeg or bmp?

If I edit an image file using some application like Gimp, Photoshop or MSPaint, while saving I will be asked to select the required file-format. There are different formats available, the common ones ...
3
votes
5answers
9k views

How to get creamy skin tone in Lightroom

I googled some tutorials on "creamy lightroom", but most of what I found ended up turning my photos' skin tones too orange, too "vintage". I tried desaturating Orange to counter this, but the ...
5
votes
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 ...
0
votes
1answer
497 views

How is colour balancing performed in post processing of raw images

I had asked a question previously here which though not duplicate but is related to this. Asking this one as I feel it is different. My question is basically related to colour balancing/colour ...
5
votes
1answer
534 views

How can I improve the results of my proprietary RAW processing pipeline?

I am doing some experiment with Raw image processing using two post processing tools: Adobe PhotoShop (PS) CS5 Proprietary Image processing pipeline code. Data Capture: I captured some raw ...
19
votes
5answers
8k views

How can I tell exactly what changed between two images?

For example, for a recent conversation about JPEG compression I wanted to compare pixel for pixel what changed between two JPEGs (one with compression level 100, and one with compression level 95). ...
4
votes
3answers
4k views

How can I resize Raw images and store them back in the original format?

I have some raw images captured using Canon,Nikon,Minolta cameras.(*.CR2, *.NEF, *.MRW) I want to change resize them and store them back as the original format. I checked in two tools, Canon ...