XML Parser in OpenCV

Question

I have a file locations.xml which contains image filenames, and positions of rectangles drawn on the corresponding image. The XML node structure is as follows:

<?xml version="1.0" encoding="ISO-8859-1"?>
<tagset>
  <image>
    <imageName>ryoungt_05.08.2002/aPICT0034.JPG</imageName>
    <resolution x="960" y="1280" />
    <taggedRectangles>
      <taggedRectangle x="196.0" y="901.0" width="111.0" height="67.0" offset="0.0" rotation="0.0" userName="admin" />
      <taggedRectangle x="116.0" y="896.0" width="59.0" height="69.0" offset="0.0" rotation="0.0" userName="admin" />
      <taggedRectangle x="442.0" y="794.0" width="424.0" height="67.0" offset="0.0" rotation="0.0" userName="admin" />
      <taggedRectangle x="212.0" y="793.0" width="200.0" height="66.0" offset="0.0" rotation="0.0" userName="admin" />
      <taggedRectangle x="99.0" y="560.0" width="302.0" height="76.0" offset="0.0" rotation="0.0" userName="admin" />
      <taggedRectangle x="107.0" y="791.0" width="84.0" height="66.0" offset="0.0" rotation="0.0" userName="admin" />
      <taggedRectangle x="512.0" y="682.0" width="366.0" height="74.0" offset="0.0" rotation="0.0" userName="admin" />
      <taggedRectangle x="104.0" y="678.0" width="376.0" height="73.0" offset="0.0" rotation="0.0" userName="admin" />
    </taggedRectangles>
  </image>

I need to open this file in OpenCV and read it such that for every image filename in the XML file, the corresponding image will be opened in a window, and the rectangles will be drawn on the corresponding image.

Basically I need to open these files and see the rectangles to match them with rectangles drawn on the same images using a text detection algorithm. But it's handling the XML files that have me stumped. Any help is appreciated.

if it's your xml file, you could switch from json to xml and save parsing time. because json parsing is much simpler and faster than xml. :) — Evgen Bodunov, Feb 11 '12 at 11:41
JSON is not an option. Because all the files are not mine. And I do not know anything about JSON yet. And I'll have to figure out how ti incorporate the JSON parser results into OpenCV function arguments. — Riddhiman Dasgupta, Feb 11 '12 at 15:31

antoine · Answer 1 · 2020-06-03T12:34:31.463

2

OpenCV has some (de-)serialization tool which support XML, YAML and JSON file format

You can deserialize your XML into OpenCV objects directly. Take a look at the example here.

But this is only useful when OpenCV is involved on both sides. XML parser requires the <opencv_storage> tag.

edited Jun 03 '20 at 12:34

answered Jun 03 '20 at 11:14

antoine

1,293
9
22

score 2 · Answer 2 · edited May 23 '17 at 12:21

2

OpenCV is OpenCV and XML is XML. One has not much to do with the other.

Check this thread

What is the best open XML parser for C++?

I personally used pugixml and I was content

edited May 23 '17 at 12:21

Community

1
1

answered Feb 11 '12 at 11:38

Jakub M.

30,095
43
103
169

1

Yes, I've thought of using TinyXML or something more full-fledged, but do I need to use a different parser for my rather simple needs? Is there no way to do it using the inbuilt XML/YAML handling functions in OpenCV? – Riddhiman Dasgupta Feb 11 '12 at 15:30

XML Parser in OpenCV

2 Answers2