Rizwan Ahmed Ansari's research while affiliated with Symbiosis Institute of Technology and other places

Publications (27)

Article
Techniques for the semantic segmentation of remotely sensed imageries for building footprint identification have been widely studied and several supervised and unsupervised techniques have been proposed. The ability to perform online mapping and accurate segmentation on a large scale by taking into account the multifariousness inherent in aerial im...
Article
This paper presents a multiresolution textural approach to change detection in multitemporal polarimetric synthetic aperture radar images. Several change detection methods utilizing wavelet based features from remotely sensed images have been developed previously. The aim of this paper is to investigate and propose a texture based change detection...
Article
Full-text available
As the global urban population grows due to the influx of migrants from rural areas, many cities in developing countries face the emergence and proliferation of unplanned and informal settlements. However, even though the rise of unplanned development influences planning and management of residential land-use, reliable and detailed information abou...
Article
Multiresolution analysis (MRA) methods have been successfully used in texture analysis. Texture analysis is widely discussed in literature, but most of the methods which do not employ multiresolution strategy cannot exploit the fact that texture occurs at various spatial scales. This paper proposes a methodology to identify different classes in sat...
Article
This contribution proposes a multiresolution analysis (MRA)-based composite technique for image restoration by noise filtering in satellite images. Multiresolution techniques provide a coarse–fine and scale-invariant decomposition of images for analysis and interpretation. MRA methods effectively handle the noise because of their multiscale feature...
Article
Full-text available
Many cities in developing countries are facing rapid growth of dynamic slum areas but often lack detailed information and analysis on these informal settlements. Multiresolution analysis (MRA) has been successfully used in texture analysis. Texture analysis is widely discussed in literature, but most of the methods which do not employ multiresoluti...
Article
Full-text available
Near real time processing and feature extraction from high-resolution satellite images aids in various applications of remote sensing including segmentation, classification and change detection. The latest generation of satellite sensors are able to capture the data at a very high spatial, spectral and temporal resolution. The processing time requi...
Chapter
The rapid development of technology has made archival and transmission of multimedia information such as music, image, and video very convenient. However, it has also introduced new challenges related to privacy and security of data. Therefore, there is a compelling need for ensuring of authenticity and protection of ownership. For providing securi...
Article
This paper presents an overview of remotely sensed image denoising based on multiresolution analysis. In this paper, the wavelet, curvelet and contourlet transforms are used for denoising of remotely sensed images with additive Gaussian noise. The curvelets and contourlets are two kinds of new multi-scale transforms which can capture the intrinsic...
Article
This article presents a new technique for denoising of remotely sensed images based on multi-resolution analysis (MRA). Multi-resolution techniques provide a coarse-to-fine and scale-invariant decomposition of images for image processing and analysis. The multi-resolution image analysis methods have the ability to analyse the image in an adaptive m...
Article
Full-text available
This article presents techniques for noise filtering of remotely sensed images based on Multi-resolution Analysis (MRA). Multiresolution techniques provide a coarse-to-fine and scale-invariant decomposition of images for image interpretation. The multiresolution image analysis methods have the ability to analyze the image in an adaptive manner, cap...
Chapter
The Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard is a real revolution in wireless metropolitan area networks (Wireless MANs) that enables high speed access to data, video, and voice services. Worldwide Interoperability for Microwave Access (WiMAX) is the industry name given to the 802.16-2004 amendment by the vendor inte...

Citations

... Therefore, in order to apply these trained data-hungry models for other specific domains, knowledge transfer learning should be considered; specifically, when data-hungry models are applied for remote sensing domain (RSD), they have to utilize a large-scale dataset (e.g., ImageNet [18]) to sufficiently stimulate their potential and then better adapt for various downstream tasks (e.g., scene classification, object detection, and semantic segmentation) in the RSD. Until now, many efforts [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] have demonstrated that the consensus solution of supervised pre-training based knowledge transfer learning for model training has basically formed, which needs to pre-train the model on a large-scale dataset with manual annotation and then directly fine-tune pre-trained models on downstream task datasets in the RSD. ...
... Moreover, with reference to the climatic conditions in the GMS, we divided the annual VV and VH time-series images into four groups and performed intra-group mean compositions, yielding eight phenological backscattering metrics for each year. Since texture features highlight the local spatial characteristics of different land covers 40 , we calculated five texture variables for the VV and VH images each year using the gray-level co-occurrence matrix (GLCM). These texture variables included angular second moment (ASM), entropy (ENT), inverse difference moment (IDM), correlation (CORR), and sum average (SAVG). ...
... Traditional machine learning methods such as support vector machine (SVM), decision tree [15], and deep learning [13,16] methods have been explored. Deep learning approaches were recently discussed, focusing on input characteristics and using time and frequency transformation [17,18]. ...
... In recent years, many scholars have carried out researched on the denoising algorithm of dictionary learning sparse representation [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27], and achieved many achievements under various noises, making up for the shortcomings of traditional denoising methods. For example, Elad proposed a denoising algorithm based on a fixed dictionary, but the fixed dictionary ignored the utilization of image pixel information [12]. ...
... Scientific research has been carried out in exploiting texture analysis to clearly identify and capture informal settlements [18,31]. In particular, several studies have explored texture feature algorithms such as grey level co-occurrence matrix (GLCM) [32][33][34][35], contourlets [36], curvelets [37], lacunarity [38][39][40][41], local Binary Patterns (LBPs) and Line Support Regions (LSRs) [42]. In other studies [18,42,43], spectral information, spectral indices and textural information have been integrated for improved accuracy, with NDVI being the widely used spectral index. ...
... In pixel-based methods, it is important to understand and infer objects and their spatial relationships in an image [11][12][13]. Spatial information extraction techniques such as those based on the grey level co-occurrence matrix (GLCM) have been employed to extract the underlying texture in the image to achieve more accurate classification, while texture-feature-based classification techniques were also explored in a few applications [14] in combination with support vector machines to improve performance [15,16]. ...
... CC BY 4.0 License. further processed through the use of a 2D median filter (Figure 2 (e)) to smooth out the surface and reduce noise (Ansari and Buddhiraju, 2018). Furthermore, filling algorithms can be used to counteract artifacts causing sinks and holes with no physical 125 meaning that typically arise in remote sensing. ...
... Advancements in sensor technology, particularly in terms of enhanced spatial and spectral resolutions, have allowed detailed characterisation of these urban deprived areas Fallatah et al., 2022). Various high-resolution earth observation (EO) data have been tested to map informal settlements, which include commercial satellites such as Quickbird imagery (Kohli et al., 2016;Mboga et al., 2017;Persello and Stein, 2017), World view (Kuffer et al., 2016;Ansari and Buddhiraju, 2019), and GeoEye (Fallatah et al., 2018(Fallatah et al., , 2020(Fallatah et al., , 2022. However, selection of the proper remote sensing data for a particular application is controlled by factors such as cost and resolution (Mahmoud 2021). ...
... The development of Internet technology has diversified the tourist demand for information services of scenic spots. More and more tourists are acquiring scenic spot information from the Internet, and actively sharing their travel photos with others [1][2][3][4]. Many travel photos contain the visual features of scenic spots, which reflect the background knowledge of the scenic spots and provide a wealth of relevant information (e.g. ...
... The compressive sensing technique may further be modified by using variable block sizes depending on the level of detail [1]. Image blocks with low local variance may have larger block sizes sparse coded using a complete dictionary, whereas image blocks exhibiting larger local variance can be learnt using smaller block sizes using over-complete dictionaries. ...