Koteswar Rao Jerripothula

Various types of saliency cues exist, all of which can be instrumental in the foreground extraction. It brings us to an interesting problem of effectively combining them. Note that earlier works either fuse them in the spatial domain or introduce dedicated terms in the energy functions to cater to multiple cues. In contrast, this paper investigates the appearance domain and proposes a novel appearance fusion framework, which we refer to as AppFuse. It is an intuitive framework for fusing candidate appearance models into the desired one for an energy function. Thus, we do not require any alterations in the energy function anymore. Like any fusion strategy, the proposed framework also requires guidance, which we facilitate through reliability and mutual consensus phenomena. To demonstrate the efficacy, we leverage it to solve a foreground extraction problem named video co-localization, where we propose two novel concepts i) hierarchical co-saliency and ii) mask-specific proposals. Our fusion results ensure that similar objects get highlighted sufficiently to ensure localization simply by respecting our framework and different spatiotemporal constraints. Our exhaustive set of experiments using both hand-crafted and learned saliency cues reveal that our approach comfortably outperforms several competing localization methods on standard benchmark datasets.

Recent advances in the joint processing of a set of images have shown its advantages over individual processing. Unlike the existing works geared towards co-segmentation or co-localization, in this article, we explore a new joint processing topic: image co-skeletonization, which is defined as joint skeleton extraction of the foreground objects in an image collection. It is well known that object skeletonization in a single natural image is challenging, because there is hardly any prior knowledge available about the object present in the image. Therefore, we resort to the idea of image co-skeletonization, hoping that the commonness prior that exists across the semantically similar images can be leveraged to have such knowledge, similar to other joint processing problems such as co-segmentation. Moreover, earlier research has found that augmenting a skeletonization process with the object’s shape information is highly beneficial in capturing the image context. Having made these two observations, we propose a coupled framework for co-skeletonization and co-segmentation tasks to facilitate shape information discovery for our co-skeletonization process through the co-segmentation process. While image co-skeletonization is our primary goal, the co-segmentation process might also benefit, in turn, from exploiting skeleton outputs of the co-skeletonization process as central object seeds through such a coupled framework. As a result, both can benefit from each other synergistically. For evaluating image co-skeletonization results, we also construct a novel benchmark dataset by annotating nearly 1.8 K images and dividing them into 38 semantic categories. Although the proposed idea is essentially a weakly supervised method, it can also be employed in supervised and unsupervised scenarios. Extensive experiments demonstrate that the proposed method achieves promising results in all three scenarios.

This work studies how we can obtain feature-level ratings of the mobile products from the customer reviews and review votes to influence decision-making, both for new customers and manufacturers. Such a rating system gives a more comprehensive picture of the product than what a product-level rating system offers. While product-level ratings are too generic, feature-level ratings are particular; we exactly know what is good or bad about the product. There has always been a need to know which features fall short or are doing well according to the customer's perception. It keeps both the manufacturer and the customer well-informed in the decisions to make in improving the product and buying, respectively. Different customers are interested in different features. Thus, feature-level ratings can make buying decisions personalized. We analyze the customer reviews collected on an online shopping site (Amazon) about various mobile products and the review votes. Explicitly, we carry out a feature-focused sentiment analysis for this purpose. Eventually, our analysis yields ratings to 108 features for 4000+ mobiles sold online. It helps in decision-making on how to improve the product (from the manufacturer's perspective) and in making the personalized buying decisions (from the buyer's perspective) a possibility. Our analysis has applications in recommender systems, consumer research, and so on.

Video object co-localization is the task of jointly localizing common visual objects across videos. Due to the large variations both across the videos and within each video, it is quite challenging to identify and track the common objects jointly. Unlike the previous joint frameworks that use a large number of bounding box proposals to attack the problem, we propose to leverage co-saliency activated tracklets to efficiently address the problem. To highlight the common object regions, we first explore inter-video commonness, intra-video commonness, and motion saliency to generate the co-saliency maps for a small number of selected key frames at regular intervals. Object proposals of high objectness and co-saliency scores in those frames are tracked across each interval to build tracklets. Finally, the best tube for a video is obtained through selecting the optimal tracklet from each interval with the help of confidence and smoothness constraints. Experimental results on the benchmark YouTube- Objects dataset show that the proposed method outperforms state-of-the-art methods in terms of accuracy and speed under both weakly supervised and unsupervised settings. Moreover, by noticing the existing benchmark dataset lacks of sufficient annotations for object localization (only one annotated frame per video), we further annotate more than 15k frames of the YouTube videos and develop a new benchmark dataset for video co-localization.

Despite the advantage of exploiting interimage information by performing joint processing of images for co-saliency, co-segmentation, or co-localization, it introduces a few drawbacks: 1) its necessity in scenarios where the joint processing might not perform better than individual image processing; 2) increased complexity over individual image processing; and 3) complex parameter tuning. In this paper, we propose a simple cosaliency estimation method where we fuse saliency maps of different images using the dense correspondence technique. More important, the co-saliency estimation is guided by our proposed quality measurement that helps decide whether the saliency fusion really improves the quality of the saliency map or not. Our basic idea for developing the quality metric is that a high-quality saliency map should have well-separated foreground and background, as well as a concentrated foreground like ground-truths. Extensive experiments on several benchmark datasets including the large-scale dataset, ImageNet, for the applications of foreground co-segmentation and co-localization show that our proposed framework is able to achieve very competitive results.

Recent advances in the joint processing of images have certainly shown its advantages over the individual processing. Different from the existing works geared towards co-segmentation or co-localization, in this paper, we explore a new joint processing topic: co-skeletonization, which is defined as joint skeleton extraction of common objects in a set of semantically similar images. Object skeletonization in real world images is a challenging problem, because there is no prior knowledge of the objects shape if we consider only a single image. This motivates us to resort to the idea of object co-skeletonization hoping that the commonness prior existing across the similar images may help, just as it does for other joint processing problems such as co-segmentation. Noting that skeleton can provide good scribbles for segmentation, and skeletonization, in turn, needs good segmentation, we propose a coupled framework for co-skeletonization and co-segmentation tasks so that they are well informed by each other, and benefit each other synergistically. Since it is a new problem, we also construct a benchmark dataset for the co-skeletonization task. Extensive experiments demonstrate that proposed method achieves very competitive results.

Most existing high-performance co-segmentation algorithms are usually complex due to the way of co-labeling a set of images as well as the common need of fine-tuning few parameters for effective co-segmentation. In this paper, instead of following the conventional way of co-labeling multiple images, we propose to first exploit inter-image information through co-saliency, and then perform single-image segmentation on each individual image. To make the system robust and to avoid heavy dependence on one single saliency extraction method, we propose to apply multiple existing saliency extraction methods on each image to obtain diverse salient maps. Our major contribution lies in the proposed method that fuses the obtained diverse saliency maps by exploiting the inter-image information, which we call saliency co-fusion. Experiments on five benchmark datasets with eight saliency extraction methods show that our saliency co-fusion-based approach achieves competitive performance even without parameter fine-tuning when compared with the state-of-the-art methods.

Despite recent advances in joint processing of images, sometimes it may not be as effective as single image processing for object discovery problems. In this paper while aiming for common object detection, we attempt to address this problem by proposing a novel QCCE: Quality Constrained Co-saliency Estimation method. The approach here is to iteratively update the saliency maps through co-saliency estimation depending upon quality scores, which indicate the degree of separation of foreground and background likelihoods (the easier the separation, the higher the quality of saliency map). In this way, joint processing is automatically constrained by the quality of saliency maps. Moreover, the proposed method can be applied to both unsupervised and supervised scenarios, unlike other methods which are particularly designed for one scenario only. Experimental results demonstrate superior performance of the proposed method compared to the state-of-the-art methods.