Assuming we found something, we then just try to pull off the corresponding cover from the O’Reilly site and display it. The getResultPoints() method returns the coordinates of each of the position indicators, and the getText() method returns the encoded text. Once we’ve called decode(), the reader object will have data about any QR codes it’s detected. LuminanceSource source = new BufferedImageLuminanceSource((BufferedImage)cam.getImage()) īinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source)) It’s slightly more complex in that we have to do a couple of transformations on the raw image before we can use the decoder - this is all done in the draw() method: In this case, we’re just passing it the frames coming in from the webcam. Then, we pass the reader an image that might contain a QR code. First, we set up a new reader object, like this:Ĭom. reader = new () The setup is similar to the one we’ve used in the posts on OpenCV. Of course, you can encode any other information you like. When you show the codes to the webcam, you should see the cover image appear after a short delay. Print off a few QR Codes for various O’Reilly books and start the sketch. You can get it from the qr_codes.pde file or pull it from the following codebox: Then paste in the sketch code into the main code window. Once you have the jar files, fire up Processing and then use “Sketch -> Add File” to add them to your project. (A jar file like a zip file for Java that compresses and bundles multiple files.) (But, don’t tell anybody - this probably violates some license requirement or the other. If you’re not, I’ve compiled them for you. If you’re comfortable with Java, all you have to do is go into the “core” and “javase” directories and run ant to build the jar files. The first thing to do is download ZXing and use your Java compiler to create two files: core.jar and javase.jar. Here’s an example of how to generate a code for “9780596510510,” the ISBN for Tom Igoe’s book Making things Talk: You can use a site like Kaywa to generate the code. The following image should give you the basic idea: The code also has some information used for error correction. For example, it could be a product number, a URL, or (in our case here) an ISBN. The data elements represent the encoded data. The positioning elements help the software determine the QR code’s location and orientation. A QR code has two basic parts - the three positioning elements, which are the large square blocks at the three corners, and the data elements, which is everything else. When it finds one, it superimposes the book’s cover image onto the video over the QR code.īefore jumping into the code, a bit of background. (Although Processing has a great contributed library called QRCode, the ZXing is much faster and can do recognition in realtime.) The sketch looks for QR codes with an encoded O’Reilly books ISBN (ISBNs are standard book identifiers). This Codebox shows you how to use the ZXing library (pronounced “Zebra Crossing”) to identify QR codes in a live webcam feed. Showcasing amazing maker projects of 2022 Gift the gift of Make: Magazine this holiday season! Subscribe to the premier DIY magazine todayĬommunity access, print, and digital Magazine, and more Share a cool tool or product with the community.įind a special something for the makers in your life. Skill builder, project tutorials, and more Get hands-on with kits, books, and more from the Maker Shed A project collaboration and documentation platform.Initiatives for the next generation of makers.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |