Thick horizontal line detection

Please suggest me some methods o开发者_StackOverflow社区n thick horizontal line detection in images. Any papers, libraries etc please.

---

Binary threshold the image, then use a combination of morphological operations to detect "borders that are thicker then N1 but thinner than N2" to produce several images and combine (logically AND) them to selectively detect borders of a certain expected thickness.

---

OpenCV is a good library. You may use a Hough transform to detect lines.

Note that the answer may depend on the quality of your images, some methods can be more effective that other ones.

---

If the line images are really easy to detect (say you can find the line from ten yards away), just scale the image from (width, height) to (1, height) and find the y-coordinate of the darkest pixel. Use CV_INTER_AREA when resizing.