“…Keeping these observations in mind, we propose a unique classifier that achieves a symmetric response with comparable precision and recall values while keeping both of them high. While our proposal is targeting the specific application area of image annotation [98]- [103], the proposed principle of symmetric classifier has potential applications in diverse areas of image processing and computer vision, such as self-localization [21], [45], [49], surveillance [43], [44], [48], action recognition [3], [5]- [8], [14], [85]- [87], [92]- [94], target localization and tracking [66], [67], [84], [89], shape description and object recognition [1], [16], [17], [117], image-based rendering [2], [9], [10], [88], image restoration [12], [39], [63], [78]- [83], and camera motion classification and quantification [4], [19]- [23], [46], [47], to name a few. The proposed annotation system employs multiple layers of sparse coding treating training images as predictors and the test image as target signal.…”