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An Efficient Lossless ROI Image Compression Using Wavelet-Based Modified Region Growing Algorithm
摘要： Nowadays, medical imaging and telemedicine are increasingly being utilized on a huge scale. The expanding interest in storing and sending medical images brings a lack of adequate memory spaces and transmission bandwidth. To resolve these issues, compression was introduced. The main aim of lossless image compression is to improve accuracy, reduce the bit rate, and improve the compression efficiency for the storage and transmission of medical images while maintaining an acceptable image quality for diagnosis purposes. In this paper, we propose lossless medical image compression using wavelet transform and encoding method. Basically, the proposed image compression system comprises three modules: (i) segmentation, (ii) image compression, and (iii) image decompression. First, the input medical image is segmented into region of interest (ROI) and non-ROI using a modified region growing algorithm. Subsequently, the ROI is compressed by discrete cosine transform and set partitioning in hierarchical tree encoding method, and the non-ROI is compressed by discrete wavelet transform and merging-based Huffman encoding method. Finally, the compressed image combination of the compressed ROI and non-ROI is obtained. Then, in the decompression stage, the original medical image is extracted using the reverse procedure. The experimentation was carried out using different medical images, and the proposed method obtained better results compared to different other methods.
关键词： DWT,Medical image,non-ROI,modified region growing,DCT,region of interest,merging-based Huffman encoding,SPIHT
更新于2025-09-23 15:22:29
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[IEEE 2018 2nd IEEE Advanced Information Management,Communicates, Electronic and Automation Control Conference (IMCEC) - Xi'an (2018.5.25-2018.5.27)] 2018 2nd IEEE Advanced Information Management,Communicates,Electronic and Automation Control Conference (IMCEC) - Studying the Effect of ROI on Image Quality Using ERPS
摘要： The effect of region of interest (ROI) on the overall image quality assessment was studied using subjective rating method and objective psychophysiology measurement methods (e.g., event-related potentials (ERPs) technology. Different image quality was acquired by compressing only the ROI or background area with different σ values of Gaussian Kernel Function. Also, the amplitude and latency of P300 (ERPs component at about 300-550ms) changed with different compressed types. The ROI compressed stimuli had earlier and higher P300 component than that of NROI compressed stimuli. The results showed that it was easier to detect the difference between original image and impaired image of ROI compressed stimuli than that of NROI compressed stimuli.
关键词： event-related potentials,region of interest,image quality
更新于2025-09-23 15:21:01
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Operator-bias-free Comparison of Quantitative Perfusion Maps Acquired with Pulsed-continuous Arterial Spin Labeling and Single-photon-emission Computed Tomography
摘要： Purpose: We compared the regional cerebral blood ?ow (rCBF) obtained by pulsed continuous arterial spin labeling (pCASL) and iodine-123-N-isopropyl-p-iodoamphetamine (IMP) single photon emission computed tomography (SPECT) using 3-dimensional stereotactic region-of-interest (ROI) software for automated de?nition of ROIs in anatomic regions of the brain. Methods: Thirteen patients with cerebrovascular occlusive disease and three with transient ischemic attacks underwent pCASL and IMP SPECT imaging. We compared rCBF values of each anatomic region and calculated the correlation coef?cients between pCASL and IMP SPECT. We also calculated the asymmetry index (AI) using ROIs in contralateral regions of the hemispheres. Results: The rCBF values calculated from pCASL and IMP SPECT were comparable in most segments, but rCBF in the thalamus (P < 0.0001) and hippocampus (P = 0.0006) was signi?cantly higher measured by pCASL than IMP SPECT. The correlation of rCBF between pCASL and IMP SPECT in the affected hemisphere (r = 0.50) tended to be lower than that in the normal hemisphere (r = 0.59), but not signi?cantly different (P = 0.25). Moreover, there was a ?xed bias for underestimation of rCBF by pCASL (P = 0.0047) in the affected hemisphere. The calculated AI showed a signi?cant relationship between methods (r = 0.79, P < 0.0001). Conclusion: The rCBF obtained by pCASL had positive relationships with IMP SPECT. However, it should be considered that pCASL tends to have a weak relationship with IMP SPECT in some normal regions and regions affected by cerebrovascular occlusive disease.
关键词： iodine-123-N-isopropyl-p-iodoamphetamine,3-dimensional stereotactic region-of-interest software,pulsed continuous arterial spin labeling,arterial spin labeling,regional cerebral blood ?ow
更新于2025-09-23 15:19:57
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Investigation of shutter scan acquisition parameters in a prototype chest digital tomosynthesis system
摘要： A shutter scan acquisition (SSA) method is proposed to reduce patient exposure dose in a chest digital tomosynthesis system. Projections obtained using the SSA constitute a combination of truncated and non-truncated projections. The truncated projections are images in which the lung field is set within a region-of-interest (ROI), and the non-truncated projections are full images in which the ROI is not set at all. We proposed a shutter weighting factor (SWF) as an acquisition parameter for SSA. We call the number of truncated projections divided by the number of non-truncated projections as SWF. We used a prototype CDT system and the LUNGMAN phantom with 8 and 10 mm lung nodules. 81 projections were obtained using SSA in five sets according to the SWFs. The image quality was quantified based on the contrast-to-noise ratio (CNR). We also calculated the figure of merit (FOM) to determine the proper acquisition parameters of the five sets. Both the CNR and FOM values of the 8 mm lung nodule in the selected ROI increased with increases of the SWF. However, the CNR value of the 10 mm lung nodule outside the ROI decreased with increases of the SWF, while the FOM value was maximized when the SWF was 3.05. We investigated the effect of the composition ratio of the truncated and non-truncated projections on the reconstructed images of the SSA based on the FOM values. In conclusion, we determined the proper SSA parameters in a prototype CDT system.
关键词： Digital tomosynthesis,Dose reduction method,Region of interest reconstruction,Shutter scan acquisition
更新于2025-09-19 17:15:36
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Study of modeling optimization for hyperspectral imaging quantitative determination of naringin content in pomelo peel
摘要： With the development of modern computational science and data metrology, hyperspectral imaging technology has been utilized in the field of remote sensing for the application in precision agriculture and crop quality testing. In this paper, the near infrared hyperspectral imaging (NIRHSI) technique was applied to quantitatively determine the naringin content in pomelo peel samples. Model optimization was studied by investigating the influence of system measuring conditions and parameters of the built-up HSI instrumental system. The HSI data acquisition was built up using a prevalent pushbroom scanner in the near infrared region. Calibration models were established using the partial least squares (PLS) regression in the mode of cross validation, in combined use of the Savitzky-Golay smoother (SGS) for data pretreatment. These multivariate analytical models were optimized in comparison about the region of interest (ROI) for NIRHSI model optimization. In the process of NIRHSI data acquisition, the rational values of some system measurement parameters were also tuned and tested, such as the use of different watts for light intensity, different lenses and different materials as the scanning backgrounds. Results showed that the cross-validation PLS regression methods performed well in the calibration and prediction processes, working well together with the parameter tuning of the SGS pretreatment. In addition to the fact that different materials as the scanning backgrounds obviously affected the quantitative result, there is no apparent difference in the comparing cases of different light intensities and different lenses. This work validates the capability of applying NIRHSI technique to quantitative determine the content of naringin in pomelo peel samples. The test for model optimization by comparing the measurement parameters and the system properties has prospective application ability in fields of other spectral/hyperspectral data analysis. It is an important lab simulation of remote sensing. It contributes significant theoretical reference to the design of the large-scale online hyperspectral data acquisition systems.
关键词： Pomelo peel Naringin,Near infrared hyperspectral imaging,Pushbroom scanner,Modeling optimization,Region of interest
更新于2025-09-19 17:15:36
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Region of interest–based segmented tiled adaptive streaming using head-mounted display tracking sensing data
摘要： To support 360 virtual reality video streaming services, high resolutions of over 8K and network streaming technology that guarantees consistent quality of service are required. To this end, we propose 360 virtual reality video player technology and a streaming protocol based on MPEG Dynamic Adaptive Streaming over HTTP Spatial Representation Description to support the player. The player renders the downsized video as the base layer, which has a quarter of the resolution of the original video, and high-quality video tiles consisting of tiles obtained from the tiled-encoded high-quality video (over 16K resolution) as the enhanced layer. Furthermore, we implemented the system and conducted experiments to measure the network bandwidth for 16K video streaming and switching latency arising from changes in the viewport. From the results, we confirmed that the player has a switching latency of less than 1000 ms and a maximum network download bandwidth requirement of 100 Mbps.
关键词： region of interest rendering,virtual reality,Head-mounted display,adaptive streaming,tracking sensor
更新于2025-09-16 10:30:52
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Region-of-interest based image compression using the discrete Tchebichef transform in wireless visual sensor networks
摘要： Reducing the algorithmic complexity of image compression techniques is a major challenge in wireless image sensor networks (WISNs). Many image compression standards, such as JPEG and JPEG20 0 0, are unsuitable for implementation in WISNs because of their high energy consumption. In this paper, a solution to this problem is proposed. It consists of a region-of-interest (ROI) based image compression using the discrete Tchebichef transform (DTT).The main idea is about compressing only the ROI instead of the whole image. The DTT is used as an alternative to the discrete cosine transform (DCT) due to its low complexity and good energy compaction. Simulation results have shown that the proposed method reduces the number of arithmetic operations, the processing/transmission energy consumption and the amount of transmitted data. The savings obtained generally exceed 50%. Furthermore, it has a competitive compression e?ciency compared with the state-of-the-art image compression techniques.
关键词： WISNs,Discrete cosine transform,Region-of-interest coding,Image compression,Energy consumption,Discrete Tchebichef transform
更新于2025-09-10 09:29:36
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[IEEE 2018 25th IEEE International Conference on Image Processing (ICIP) - Athens, Greece (2018.10.7-2018.10.10)] 2018 25th IEEE International Conference on Image Processing (ICIP) - Visual Saliency Analysis for Common Region of Interest Detection in Multiple Remote Sensing Images
摘要： Saliency detection is an effective tool to extract regions of interest (ROIs) from remote sensing images. However, some existing saliency detection models focus on extracting ROI from a single image, which cannot accurately detect ROI against complex background interference. In this paper, a novel visual saliency analysis and ROI extraction model is proposed to effectively extract common ROIs from remote sensing images and exclude images without ROIs. Firstly, the single saliency maps are generated by frequency-tuned (FT) method. Secondly, the cluster method based on synthesized features is proposed to group regions with similar feature into a cluster for multiple images. Thirdly, computing the mean of saliency value as the cluster saliency suppresses the saliency value of non-common ROIs. Finally, a ROI extraction method based on the maximum saliency value is proposed to extract ROIs while eliminating the image without ROIs. Experimental results indicate our model outperforms other state-of-the-art saliency detection models, achieving highest ROC and maximal PRF values.
关键词： saliency analysis,region of interest,feature clustering,Image processing,remote sensing
更新于2025-09-09 09:28:46
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[IEEE 2018 International Conference on Advances in Communication and Computing Technology (ICACCT) - Sangamner (2018.2.8-2018.2.9)] 2018 International Conference On Advances in Communication and Computing Technology (ICACCT) - Adaptive Background Subtraction in Images
摘要： Selective background subtraction is the major problem associated with background subtraction technique. For foreground detection, background modeling is used in many different applications to subtract the background and detect foreground object in the image. There are many challenges in elaborating a good background subtraction algorithm and researcher have been appropriated to developing the new innovation and enhancement techniques to overcome all the limitations. In this paper, we present selective background subtraction technique to subtract unnecessary background from the foreground and background scene.
关键词： Selective Background Subtraction,Background modelling,Region of Interest
更新于2025-09-04 15:30:14