A barcode generator may seem a bit basic, but there's some logic behind the choice: It's something I recently needed, so it's not entirely contrived. It's simple enough to do in one function, so it can be reviewed easily. UPDATE: The introduction to this post may seen a little “out there”. For some context, I had just finished watching the prior to writing this post so I definitely had some inspiration regarding zombie shoppers, Black Friday chaos, and Game of Thrones. Black Friday is coming. Hordes of angry shoppers. Stampedes of middle-aged midwestern women, their toothless gums bloodthirsty for 75% off the latest season of Game of Thrones at the local Wal-Mart. They’ll lineup outside the Wal-Mat doors on Thanksgiving at midnight. They’ll rally, beating at the locked doors with their hands and heads until their bodies are raw and bloody, like zombies from 28 Days Later. But instead of human flesh, they crave petty consumer sustenance. Their war cries of discounts and sales will reach the heavens. Arreglar cable roto en el peor sitio. Puente Inalambrico con Linksys WRT54GS. Configurar Router ADSL como Repetidor Wifi/LAN. Configuracion Router CNT - Huawei HG530. Configurar Antena Ubiquiti Modo Router. Como usar un viejo router como repetidor Wifi facilmente, paso a paso. WRT54G v8 and v8.2 DD-WRT Firmware Installation Guide. Por otro lado puedes configurarlo como AP cableandolo al router por uno de los puertos 1~4 del linksys a otro de los mismos de tu router, quitas DHCP como ya apuntaste, pones una IP fija que este fuera del rango que usas en el DHCP del router y como gateway pones la IP del router. Configura el wireless con SSID, seguridad y pass de las mismas que usas en el router. Back on the Belkin router and to the wireless area you want to set the channel to 5 or more channels off the other router. If the Netgear is channel 1, then use channel 6 or 11 for the Belkin. Configurar router linksys wrt54g repetidor wifi belkin password. And their thunderous footsteps will cause earthquakes across the Great Plains. Of course, the media won’t help — they will sensationalize every last little piece. From frostbitten families camping out all night in the blistering cold, to the little old lady trampled by raging bargain hunters as the doors open, akin to the Gallimimus stampede in Jurassic Park. All of this simply because she wanted to purchase the latest Halo game for Timmy, her little 9 year old grandson, who’s parents passed away this time last year. At a Wal-Mart. During Black Friday. And I have to ask, is all this chaos and bedlam worth it? Any shopping I do this Black Friday will be from (safely) behind my laptop screen, likely nursing a hangover from the night before with a cup of coffee and a handful of Tylenol. But if you decide you are going to venture out into the real-world and brave the bargain hunters, you’ll want to download the source code to this blog post first Imagine how silly you would feel, standing in line, waiting to checkout, only to scan the barcode on the latest season of Game of Thrones only to find out that Target has it for $5 cheaper? In the rest of this blog post I’ll show you how to detect barcodes in images using nothing but Python and OpenCV. Looking for the source code to this post? Detecting Barcodes in Images using Python and OpenCV The goal of this blog post is to demonstrate a basic implementation of barcode detection using computer vision and image processing techniques. My implementation of the algorithm is originally based loosely on. I have gone through the code and provided some updates and improvements to the original algorithm. It’s important to note that this algorithm will not work for all barcodes, but it should give you the basic intuition as to what types of techniques you should be applying. For this example, we will be detecting the barcode in the following image. # load the image and convert it to grayscale image = cv2.imread(args['image']) gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY) # compute the Scharr gradient magnitude representation of the images # in both the x and y direction using OpenCV 2.4 ddepth = cv2.cv.CV_32F if imutils.is_cv2() else cv2.CV_32F gradX = cv2.Sobel(gray, ddepth=ddepth, dx=1, dy=0, ksize=-1) gradY = cv2.Sobel(gray, ddepth=ddepth, dx=0, dy=1, ksize=-1) # subtract the y-gradient from the x-gradient gradient = cv2.subtract(gradX, gradY) gradient = cv2.convertScaleAbs(gradient). Gradient = cv2. ConvertScaleAbs ( gradient ) On Lines 14 and 15 we load our image off disk and convert it to grayscale. Then, we use the Scharr operator (specified using ksize = - 1 ) to construct the gradient magnitude representation of the grayscale image in the horizontal and vertical directions on Lines 19-21. From there, we subtract the y-gradient of the Scharr operator from the x-gradient of the Scharr operator on Lines 24 and 25. By performing this subtraction we are left with regions of the image that have high horizontal gradients and low vertical gradients. Our gradient representation of our original image above looks like. ( _, thresh ) = cv2. Threshold ( blurred, 225, 255, cv2. THRESH_BINARY ) The first thing we’ll do is apply an average blur on Line 28 to the gradient image using a 9 x 9 kernel. This will help smooth out high frequency noise in the gradient representation of the image. We’ll then threshold the blurred image on Line 29. Any pixel in the gradient image that is not greater than 225 is set to 0 (black). Otherwise, the pixel is set to 255 (white). The output of the blurring and thresholding looks like this. Closed = cv2. MorphologyEx ( thresh, cv2. MORPH_CLOSE, kernel ) We’ll start by constructing a rectangular kernel using the cv2. GetStructuringElement on Line 32. This kernel has a width that is larger than the height, thus allowing us to close the gaps between vertical stripes of the barcode. We then perform our morphological operation on Line 33 by applying our kernel to our thresholded image, thus attempting to close the the gaps between the bars. You can now see that the gaps are substantially more closed, as compared to the thresholded image above.
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