Simple color appearance model (sCAM) based on simple uniform color space (sUCS).

A new color appearance model named sCAM has been developed, including a uniform color space, sUCS. The model has a simple structure but provides comprehensive functions for color related applications. It takes input from either XYZ D65 or signals from an RGB space. Their accuracy has been extensively tested. sUCS performed the best or second-best to the overall 28 datasets for space uniformity and the 6 datasets for hue linearity comparing the state of the art UCSs. sCAM also performed the best to fit all available one- and two-dimensional color appearance datasets. It is recommended to have field tests for all color related applications.

Colour gamut mapping between small and large colour gamuts: Part I. gamut compression.

This paper describes an investigation into the performance of different gamut compression algorithms (GCAs) in different uniform colour spaces (UCSs) between small and large colour gamuts. Gamut mapping is a key component in a colour management system and has drawn much attention in the last two decades. Two new GCAs, i.e. vividness-preserved (VP) and depth-preserved (DP), based on the concepts of 'vividness' and 'depth' are proposed and compared with the other commonly used GCAs with the exception of spatial GCAs since the goal of this study was to develop an algorithm that could be implemented in real time for mobile phone applications. In addition, UCSs including CIELAB, CAM02-UCS, and a newly developed UCS, Jzazbz, were tested to verify how they affect the performance of the GCAs. A psychophysical experiment was conducted and the results showed that one of the newly proposed GCAs, VP, gave the best performance among different GCAs and the Jzazbz is a promising UCS for gamut mapping.

Color gamut mapping between small and large color gamuts: part II. gamut extension.

A wide color gamut (WCG) display has great color rendering capability and offers the opportunity to achieve a pleasing and realistic appearance in terms of image quality. To take full advantage of the large display gamut, a new gamut extension algorithm (GEA) is proposed based on a new color appearance scale, vividness. The performance of the new GEA was investigated via a psychophysical experiment together with five commonly used GEAs. In addition, two different uniform color spaces (UCSs) were also studied including the CAM02-UCS color space and a space, Jzazbz, designed for high dynamic range (HDR) and WCG applications. The results showed that the newly proposed GEA, i.e. the vividness-extension (VE) algorithm, outperformed all the other GEAs and the Jzazbz space was a promising UCS for evaluating gamut extension.

Comprehensive model for predicting perceptual image quality of smart mobile devices.

An image quality model for smart mobile devices was proposed based on visual assessments of several image quality attributes. A series of psychophysical experiments were carried out on two kinds of smart mobile devices, i.e., smart phones and tablet computers, in which naturalness, colorfulness, brightness, contrast, sharpness, clearness, and overall image quality were visually evaluated under three lighting environments via categorical judgment method for various application types of test images. On the basis of Pearson correlation coefficients and factor analysis, the overall image quality could first be predicted by its two constituent attributes with multiple linear regression functions for different types of images, respectively, and then the mathematical expressions were built to link the constituent image quality attributes with the physical parameters of smart mobile devices and image appearance factors. The procedure and algorithms were applicable to various smart mobile devices, different lighting conditions, and multiple types of images, and performance was verified by the visual data.

[Robot-assisted transaxillary thyroidectomy: our early experience].

Objective:To evaluate the feasibility, effectiveness and safety of robot-assisted transaxillary thyroidectomy (RATT).Method: The clinical data of 66 patients undergoing RATT from November 2016 to May 2018 were prospectively collected and analyzed. The average age was (38.61±11.72) years, 57 cases were female and 9 cases were male. Preoperative fine needle aspiration biopsy revealed papillary thyroid carcinoma in 58 cases and follicular thyroid tumor in 8 cases.Result:All the patients successfully completed RATT, and there was no open operation, in which 54 cases of ipsilateral lobetomy and isthmus resection and ipsilateral central lymph node dissection, 8 cases with ipsilateral lobectomy and contralateral near-total lobectomy, and total thyroidectomy with ipsilateral central lymph node dissection and selective neck dissection combined with retroauricular approach in 4 cases. The mean operative time was (124.30±23.41) min, and the average bleeding volume was (17.73±8.28) ml. The mean diameter of thyroid papillary carcinoma was (0.71±6.22) cm, and the postoperative drainage volume was (67.57±25.11) ml. The average postoperative hospitalization time was (3.24±0.81) days. 3 cases (4.5%) had temporary laryngeal nerve palsy after operation, and 1 case (1.5%) had temporary hypocalcemia after operation, all recovered after one month. No postoperative bleeding, subcutaneous emphysema, drinking water cough and permanent hypocalcemia were observed. The average numbers of lymph node dissection in PTC patients were (6.26±4.76), of which 21 cases (36.2%) had lymph node metastasis, postoperative stage T1 54 cases, T2 4 cases, N1a 17 cases, N1b 4 cases. The follow-up time were 1-18 months. The postoperative cosmetic VAS score in January was (9.66±0.54). Ultrasound showed no residual glands in the affected thyroid gland, and there was no recurrence in the local and regional regions.Conclusion:RATT is safe and feasible with good aesthetic effect and can be used as an option for the treatment of thyroid diseases..

[Robotic nasopharyngectomy via combined approach of nose and oral for local recurrent nasopharyngeal carcinoma].

Objective:Surgery is one of the salvage treatments for recurrent nasopharyngeal carcinoma. The safety and efficacy of Da Vinci's robotic surgery was preliminarily investigated to resect recurrent nasopharyngeal cancer after one-course radiotherapy.Method:Since Oct 2017, Da Vinci surgery system was used to complete the operation of locally recurrent nasopharyngeal carcinoma including two approaches, such as trans oral with soft palate incision and trans oral and nose with soft palate suspended.Result:Ten patients underwent robotic nasopharyngectomy, The median operation time was 90 minutes, median follow-up time was 6 months, and all patients had clear resection margins. There was no residual, recurrent or cancer related death during short-term follow-up.Conclusion:Robotic nasopharyngectomy via combined approach of nose and mouth is safe, effective and has good local control.