We address the problem of correcting an undesirable expression on a face photo by transferring local facial components, such as a smiling mouth, from another face photo of the same person which has the desired expression. Direct copying and blending using existing compositing tools results in semantically unnatural composites, since expression is a global effect and the local component in one expression is often incompatible with the shape and other components of the face in another expression. To solve this problem we present Expression Flow, a 2D flow field which can warp the target face globally in a natural way, so that the warped face is compatible with the new facial component to be copied over. To do this, starting with the two input face photos, we jointly construct a pair of 3D face shapes with the same identity but different expressions. The expression flow is computed by projecting the difference between the two 3D shapes back to 2D. It describes how to warp the target face photo to match the expression of the reference photo. User studies suggest that our system is able to generate face composites with much higher fidelity than existing methods. CR Categories: I.4.9 [IMAGE PROCESSING AND COM-PUTER VISION]: Applications

Yang, F., Liu, F.-h. and Rowland, G. 2013. Effects of diurnal temperature range and seasonal temperature pattern on the agronomic traits of fibre flax ( Linum usitatissimum L.). Can. J. Plant Sci. 93: 1249–1255. Three cultivars of fibre flax (Linum usitatissimum L.), Viking, Argos and Ariane, were used to study the effect on various agronomic traits of diurnal temperature ranges (DIF) and seasonal temperature patterns (STP) applied throughout the crop growth period. Diurnal temperature ranges were set at 5, 10 and 15°C with the same daily mean temperature and accumulated growing degree days (GDDa), under a parabolic STP. Seasonal temperature patterns were set following parabolic, anti-parabolic and quasi-horizontal configurations with DIF set at 10°C. The results showed that DIF or cultivar had a significant influence on the biomass, plant height (PH), stem diameter (SD), length of technical stem (LTS), weight of technical stem (WTS), fibre weight (FW), fibre content (FC) and seed weight per pot (SWp). Seasonal temperature pattern also had a significant influence on these traits except for WTS and FW. Significant interactions were observed between DIF and cultivar, affecting all traits with the exception of FW, and between STP and cultivar, affecting biomass, PH, SD and WTS. Diurnal temperature range set at 10°C was optimal for biomass, PH, SD, LTS, WTS, and FW, while DIF set at 5°C benefited FC and SWp. Among the different STP configurations, anti-parabolic pattern was optimal for biomass, PH, SD, LTS and FC, and the quasi-horizontal pattern best fit SWp. In conclusion, the combination of DIF set at 10°C and anti-parabollic STP provided the most favorable temperature conditions for fibre flax growth, which is the situation with winter flax production in Yunnan, China.