This question already has an answer here:
GetPixel after SetPixel gives incorrect result
(1 answer)
Closed 8 years ago.
I did some encryption technique which encrypted the image LENA.jpg.I saved it as a encrypted image.When I am reading the same matrix for decription process I noticed a change in the values of the matrix.Image has lost some of its characteristics.When I decrypted the Matrix (encrypted) without saving as picture the output is perfect..But Once saved it loses its quality...Why it is happening...
I am attaching the decrypted image..you can see some pixels missing clearly..
When you "save as picture" what format are you using? Some are lossy but it sounds like you need a lossless format for this.
What you are looking for is aptly explained in this SO answer.
If you had saved the image in a .jpg format, it is to be expected. JPEG is by default a lossy format. It does have some lossless variants though.
Related
I have raw image data, a pixel array (actually a single string of data) that I want to convert to the most basic and minimal DNG format/file. I saw different approaches utilizing libtiff and libjpeg.
Is there a simpler and more straight forward way to do this in SWIFT using Core Graphics, Core Image or yet another SWIFT API?
The image data are still in the original Bayer matrix format (CFA pattern is RGGB) without any tags.
I downloaded the over 100 pages of the latest Adobe DNG format specification, but I cannot find the actual byte order or structure of the DNG file in there... I am pretty lost with this document.
Any help and hints are highly appreciated.
At work I have to record a lot of data from png data. Every time I have to manually record the digits (e.g. mean\SD 101.1\11) on the excel sheet and read it with Matlab. Would it be possible that Matlab could directly read the digits from the PNG image, so that lots of work could be saved?
I know it might involve pattern recognition, but still hope that there may be someone who has done this before.
You can make use of Optical Character Recognition (OCR). The code for it is available here
I'm trying to convert a 3-channel rgb raw image to a one channel image in Matlab (or any other conversion software for that matter). I've tried concatenating but that was still unsuccessful. Any other suggestions?
The raw image I found online and I personally don't care which format it's in (whether NEX/ARW/etc). Just need to get it to one channel.
Thanks
This question already has answers here:
segment digits in an image - Matlab
(2 answers)
Closed 9 years ago.
I am doing a project to recognize the digits in a calculator screen. The full image is shown
.
After some image processing, I have extracted only the screen from the full image as shown
.
But the digits are getting overlapped. Can anyone suggest how to remove the bridges or connections between the images?? Would any morphological image processing using bwmorph() be of utility? Please help..
May be you can try these two ideas see where it takes you
1). I would clean up the salt and pepper noise first.
2). then use erodedBW = imerode(originalBW,se)
of course you have to play aroud with se to find the one that works best for you.
I wanted to import a tif image into Matlab workspace as a variable using File/import data tool. But I got the following error "Warning: The datatype for tag SamplesPerPixel should be TIFF_SHORT instead of TIFF_LONG. This may cause data corruption". The image type is float single, 32 bit. and size is really big (4144,12619,7). Can matlab read and display such an image. What does this error mean? and how can I correct it?
Thank you so much
Read the TIFF specification.
From the warning message it appears there's some problem with the format chosen. When reading a TIFF file, each IFD has many entries, one of them being SamplesPerPixel (see page 24 of the specification). This should be of type SHORT (see page 15 for the list of types and what they are). However, apparently, you have type LONG there. That seems to be causing problem. Either matlab is identifying it incorrectly, or the software you used to save the image is not following the TIFF specification.