Creating SVG image in c++ - c++

I want to create a SVG image programmatically using preferably c++ from some image points. Can anyone help me with that?

simple-svg is a header only svg lib easy to use:
simple_svg_1.0.0
Here is an example how to use it: main_1.0.0.cpp
It is also hosted on GitHub.

You could check out LibBoard. I have no experience with it myself, so I can't vouch for its usefulness, but it does appear to be what you're looking for. I'm not sure how complicated your target image is going to be, but the website states:
For now, LibBoard can handle primitives like lines, rectangles,
triangles, polylines, circles, ellipses and text.
In future releases, bitmap insertion should be supported.
See the TODO file for a list of features that should be added in future releases.
So you'll have basic functionality from it, and you can probably mess around with the basic list of shapes to create some pretty complicated images.

I used GraphViz to do that, using 'dot' language, check it out.

Related

Disparity Map post processing in OpenFrameworks

After long hours I finally managed to get a stereo disparity map with a single camera. The result is rather spotty as one would expect, so I would like to apply some filter to improve the quality. The problem is that I'm not using pure OpenCV, but the plugin for OpenFrameworks (ofxCv), meaning I can't use this:
http://docs.opencv.org/3.1.0/d3/d14/tutorial_ximgproc_disparity_filtering.html
There has to be a way how I can apply the WLS filter, or something similar in this situation. WLS appears to be implemented in OpenCV, but I can't access it through the plugin, and direct access also doesn't seem to work.
Does anybody know how I can apply that filter, or has any other, general, disparity map post-processing advice?
I'm not sure what OpenCV functionality is available to you. But just a suggestion, maybe use the implementation from OpenCV in your project. Look at the file: https://raw.githubusercontent.com/opencv/opencv_contrib/master/modules/ximgproc/src/disparity_filters.cpp
Copy any additional files you may need to your project and try building. With basic OpenCV support you might be able to make it work.

Pango layout flow around container (image)

I'm using Pango for text layouting without the cairo backend (currently testing with the win32 backend). And I like to know if pango is capable of a flow layout around an image, or any given container. Or maybe inside a custom container.
Something like this: Flow around image
I have checked many examples and the Pango API and didn't found such a feature. Maybe I'm missing something or Pango does not have this feature.
As I said in this answer, you can't. I went through the source code Pango graphics handling is primitive to the point of uselessness. Unless there's been some major reworking in the past year, which the release notes don't indicate, it's probably the same now.
The image you provide as an example is only available as PDF at the moment which requires every line, word and glyph be hard-positioned on the page. While theoretically possible to check the alpha channel of the image to wrap the text around the actual image instead of the block it contains, this has not (to the best of my knowledge) ever been implemented in a dynamic output system.
Pango, specifically, cannot even open "holes" in the text for graphics to be added later and, at the code level, doesn't even have the concept of a multi-line cell - hence a line being the size of its largest component.
Your best bet is to look at WebKit for more complex displays. I, for one, have pretty much given up on Pango and it seems to be getting less popular.

Augmented Reality-PC

I recently saw the virtual mirror concept on you tube, I tried it out and researched about it. It seems that the creators have used augmented reality so that people can see the output on their screens. On researching I found out that we identify a pattern on which a 3D image is superimposed.
Question 1:How are they able to superimpose the jewellery and track the face of the person without identifying any pattern?
I also tried to check various libraries that I can use to make a program similar to the one they show. Seems to me that a lot of people are using Android phones and iPhones and making apps that use augmented reality.
Question 2:Is there any way that I can use c++ and try to make a program that uses augmented reality?
Oh, and the most important thing, the link to the application is provided below:
http://www.boutiqueaccessories.com.au/virtual-mirror/w1/i1001664/
Do try it out. Its a good experience. :D
I'm not able to actually try the live demo, but the linked video suggests that they either use some simplified pattern recognition (get the person's outline), or they simply track you based on the initial image (with your position/texture being determined by the outline being shown.
Following the video, it's easy to see that there's no real/advanced AR behind this. The images are simply overlayed or hidden (e.g. in case it's missing track of one ear due to you looking to the side) and they're not transformed (no perspective or resizing happening). They definitely seem to track the head (or features like ears, neck, etc.). depending on your background and surroundings that's actually a rather trivial task.
Question 2: Sure! There are lots of premade toolsets out there, but you could as well use some general image processing library such as OpenCV to do the math. Augmented reality usually uses some kind of pattern (e.g. a card or page with a known pattern) to determine the correct position and transformation for the contents to be added to the image. There are also approaches using the device's orientation and perspective changes in camera images to determine depth/position (I really like this demo).

Libraries for reading and writing vector graphics - polling x,y for color

I'm doing an implementation for a path planning algorithm. I'd really like to be able to load in a 2d "environment" in vector graphics (svg) format, so that complex obstacles can be used. This would also make it fairly easy to overlay the path onto the environment and export another file with the result of the algorithm.
What I'm hoping to be able to do is use some kind of library in my collision test method so that I can simply ask, "is there an obstacle at x, y?" and get back true or false. And then of course I'd like to be able to add the path itself to the file.
A brief search and a couple of downloads left me with libraries which either create svg's or render them but none really gave me what I need. Am I better off just parsing the xml and hacking through everything manually? That seems like a lot of wasted effort.
1.This may be a bit heavyhanded, but Qt has a really great set of tools called the Graphics View Framework. Using these tools, you can create a bunch of QGraphicsItems (polygons, paths, etc..) in a QGraphicsScene, and then query the scene by giving it a position. Using this you'll never actually have to render the scene out to a raster bitmap.
http://doc.trolltech.com/4.2/graphicsview.html, http://doc.trolltech.com/4.2/qgraphicsscene.html#itemAt
2.Cairo has tools to draw all sorts of shapes as well, but I believe you'll have to render the whole image and then check the pixel values. http://cairographics.org/
The SVG specification includes some DOM interfaces for collision detection:
http://www.w3.org/TR/SVG/struct.html#_svg_SVGSVGElement__getEnclosureList
http://www.w3.org/TR/SVG/struct.html#_svg_SVGSVGElement__getIntersectionList
Using these methods, all "obstacles" (which can be groups of primitive elements, using the <g> element) should be labelled as a target of pointer events.
These methods are bounding-box based, however, so may not be sophisticated enough for your requirements.
Thanks for the responses. I didn't manage to get anything working in QT (it's massive!) or Cairo, and I ended up going with PNGwriter, which does pretty much what I wanted except, of course, that it reads and writes PNG's instead of vector graphics. The downside here is that my coordinates must be rounded off to even pixels. Maybe I'll continue to look into vector graphics, but this solution is satisfactory for this project.

Animation with C++

is there anyway to build rich animation with C++?
I have been using OpenCV for object detection, and I want to show the detected object with rich animation, Is there any easy way to realize this?
I know flash can be used to easily build rich animation. But can flash be reliably integrated with C++ and How?
Also, Can OpenGL help me with this? To my knowledge, OpenGL is good for 3D rendering. But I am more interested in showing 2D animations in an image. So I am not sure whether this is a right way to go.
Another question, how are those animations in augmented reality realized? What kind of library are they using?
Thank you in advance.
Its difficult to tell if this answer will be relevant, but depending on what sort of application you are creating you may be able to use Simple DirectMedia Layer.
This is a cross-platform 2D and 3D (via OpenGL) media library for C, C++ and many other compatible languages.
It appears to me that you wish to produce an animated demo of your processing results. If I am wrong, let me know.
The simplest way to produce a demo of a vision algorithm is to dump the results to a distinct image file after each processed frame. After the processing session, these individual image files are employed to prepare the video using e.g. mencoder. I employed such procedure to prepare this.
Of course, your program can also produce OpenGL. Many people dealing with 3D reconstruction do that. However, in my opinion that would be an overkill for simple 2D detection. Producing flash would be an even greater overkill.