DCT-domain spatial transcoding using generalized DCT decimation

[[abstract]]In this paper, we propose a generalized DCT-domain spatial downscaling scheme to improve the visual quality. We analyze the filtering performances and computational complexities of the proposed scheme and the pixel-domain downscaling schemes. The analyses show that the proposed scheme can reduce the aliasing artifact compared to the existing schemes, while the computational complexity may be increased. We also integrate the proposed decimation scheme into the cascaded DCT-domain transcoder for spatial downscaling of a pre-encoded video into its quarter size. Experiments show the proposed approach can achieve better visual quality than the existing schemes.[[fileno]]2030144030019[[department]]電機工程學

Changes in Photochemical Efficiency and Differential Induction of Superoxide Dismutase in Response to Combined Stresses of Chilling Temperature and Relatively High Irradiation in Two <em>Chlorella</em> Strains

The green algae Chlorella sp. DT (DT) and Chlorella pyrenoidosa 211-8b (8b) had similar cell growth rates and photochemical efficiency (Fv/Fm) when they were cultivated under a moderate irradiance of 120 μmol photons m−2 s−1 in combination with a series of temperatures that decreased from 32 to 7°C. Upon shifting the cultures to the relatively high irradiance of 240 μmol photons m−2 s−1, DT exhibited higher cell growth rates than 8b under the chilling temperatures of 20°C and 15°C and differences in the Fv/Fm and Chl a/b ratios from 8b. In particular, DT possessed more new differentially induced SOD isoforms than 8b