Region of interest in - roi

I'm a developing an application using jasper library and i need to encode ROI some ROI (region of interest).
I read in the jasper official website https://www.ece.uvic.ca/~frodo/jasper/ that, only the decoder support ROI.
But i saw in the jpc codec source code https://github.com/mdadams/jasper/blob/master/src/libjasper/jpc/jpc_cs.h a field call "roishift".
Did someone know what it is for?
Thank you for your answer!

jasper is a dead project. It is no longer consider an active reference JPEG 2000 implementation, why would anyone use japser these days ?
OpenJPEG does implement the simple ROI upshift a whole component, if you can pick an active JPEG 2000 implementation.

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Leadtools bitmap to OpenCV Mat and back

I have a LeadTools Bitmap that I need to convert to OpenCV's Mat to do some processing on, and then convert it back to LeadTools Bitmap. What is the best way to do this?
I know OpenCV can read files and write them back, but that is not an option for me for many reasons that are not worth mentioning here
I'm using C++, but samples in any programming languages are appreciated.
Thank you for using the LEADTOOLS SDK. Can you please send an email to support#leadtools.com with the following information:
What version of the LEADTOOLS SDK are you using?
Some sample images that you are wanting to convert
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Convert pcl xyzrgb(a) point cloud to images from different angles of the cloud

I would like to generate images from my point cloud (Kinect) from different angles, but the only function to take snapshots seems to require an open Viewer (open Window) and saves the images to a file. I would like to process them later and show them in a custom viewer, so storing in RAM is necessary.
Is the point cloud library providing such a method? Or does anybody knows how the approach with pcl would look like?
My second approach is to use opencv mats. Then use the projectPoints method for the projection, but this works on xyz-coordinates not xyzrgb(a) and I will loose the information which color from the pointcloud point belongs to the new projected image.
I stuck a little bit here :( and hope you can help me :)
Many thanks
Greetings
Carlo
I don't believe there is a way to do that using PCL functions. However PCL uses VTK to build it's viewer and I believe you would be able to do what you're talking about by using VTK functionality, though it's likely going to be more complicated. This article might be a good start.

Image processing and Computer Vision

I would like to use Smalltalk (Pharo) to better refactor my image processing and computer vision code/algorithms, written in other languages. I have not found a lot of examples online where Smalltalk is used for processing images (or video frames). I would like to know whether
i) there is an opencv/image/computer vision library available for Smalltalk that is easily installed or
ii) someone could give an example of how to access the pixel data in an image and threshold it using Smalltalk.
For the first question, you can maybe write your own interface using FFI to the OpenCV C-API.
For the second question, I think it's easy to use ImageReadWriter formFromFileNamed: and then can use pixelValueAt: to read the value, threshold, and then write back by pixelValueAt:put:.
There is a recent binding to OpenCV (for Pharo 7 a.t.m.) at https://github.com/feenkcom/gt4opencv

Image conversion framework

Could someone recommend an existing image conversion framework. I need to convert virtually all image formats: raster and vector, ms office, pdf, psd etc. Color precision is a must.
Thank you.
(edited)
Any platform, any language, but Windows is preferred. This would be a backend, so client platform is irrelevant.
I know I could find multiple frameworks to cover all the formats (already have), but idea is to have as few as possible.
Color precision is important as it is an image review system.
Imagemagick is the most complete image conversion tool I know, it has lot's of features to modify all types of images. The software works in cli and is available for any platform.
You can also find a lot of help on their forum.
Building on your key requirements:
to use the framework on your back-end,
to get the framework with an un-compromised ColorManagement precision
test the server-side suitability of a GhostScript framework.
Moving your solution's neutral-format to a PostScript level will solve all your other conversion related requirements.
Once your image-review system architecture settles on PostScript, "The Lingua Franca" for professional TypeSetting, both the conversion issue and the ColorManagement issue get out of the table.
Try ImageResizing if you can develeop on .net platform.
IMHO great piece of software!
Use Imagemagick as it can convert nearly all image formats.
for more info refer below link
http://www.imagemagick.org/

Streaming opencv Video

I need some ideas about how to stream video feed coming from opencv to a webpage. I currently have gStreamer, but I don't know if this is the right tool for the job. Any advice on using gStreamer or any hyperlinks to tutorials would be helpful and appreciated!
Thanks!
OpenCV doesn't provide an interface for streaming video, which means that you'll need to use some other techonology for this purpose.
I've used GStreamer in several professional projects: this is the droid you are looking for.
I do not have any experience w/ streaming OpenCV output to a website. However I'm sure this is possible using gstreamer.
Using a gstreamer stream, it is possible to get data and convert the data in to OpenCV format. I recommend you read up on GstAppSink and GstBuffer.
Basically, if I remember correctly, you must run a pipeline in the a background thread. Then using some function in gst_app_sink, you can get the buffer data from the sink.
A quick lookup on the issue, you had to use GST_BUFFER_DATA for this
I remember having to convert the result from yCBCr to bgr, a collegue had problems as the conversion of opencv was inadequate. So you might have to write your own. (This was back in the IplImage* days)

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