Showing papers on "JPEG 2000 published in 1970"

Image Compression using Modified Haar Wavelet-Base Vector Quantization

Abstract: This research presents an image compression algorithm using modified Haar wavelet and vector quantization. For comparison purposes, a standard Haar wavelet with vector quantization and SPIHT, which is used in JPEG2000, are compared with the proposed method using Peak Signal-to-Noise Ratio (PSNR). The proposed method shows better results on average over the compared methods.

Color Image Transcoding of Lossless Encoder and Standard Lossy Decoder based on JP2K

Abstract: In JPEG2000 (JP2K) color image system, loss less coding signal is not able to be reconstructed with lossy decoder directly. Then, this report proposes a new transcoding between lossless encoder and standard lossy decoder for color image signals base on JP2K. A proposed encoder is required reversible color transform (RCT) and reversible discrete wavelet transform (RDWT) with compatibility to standard lossy decoder based on JP2K (JP2K lossy decoder). To improve the compatibility, proposed encoder is designed by using Non-scaled RCT and Non-Scaled RDWT with embedding scaling parameter into quantization header. Then, this method can be practical use with JP2K lossy decoder without any change. It also reduces total rounding error and lifting steps. The results show that proposed method can keep lossless coding performance and improve transcoding functionality to JP2K lossy decoder. The quality of transcoding image was achieved to 50.05 dB (PSNR).

A Copyright- and Privacy-Protected Diabetic Retinopathy Diagnosis Network

Abstract: This paper proposes a copyright- and privacyprotected diabetic retinopathy (DR) diagnosis network. In the network, DR lesions are automatically detected from a fundus image by firstly estimating non-uniform illumination of the image, and then the lesions are detected from the balanced image by using level-set evolution without re-initialization. The lesions are subsequently marked by using contours. The lesion-marked fundus image is subsequently shared for intra or inter hospital network diagnosis with copyright and privacy protection. Watermarking technique is used for image copyright protection, and visual encryption is used for privacy protection. Sign scrambling of two dimensional (2D) discrete cosine transform (DCT) and one dimensional (1D) DCT is proposed for lesion-marked fundus image encryption. The proposed encryption methods are compared with other transform-based encryption methods, i.e., discrete Fourier transform (DFT) amplitude-only images (AOIs), DCT AOIs, and JPEG 2000-based discrete wavelet transform (DWT) sign scrambling which were proposed for image trading system. Since the encryption is done after DR diagnosis, contours used for DR marking must also be visually encrypted. The proposed encryption methods are effective for strong-edge images that are suitable for lesion-marked fundus images, while random sign-based JPEG 2000, DFT AOIs, and DCT AOIs encrypt the images imperfectly. Moreover, the proposed methods are better in terms of image quality. In addition, watermarking performance and compression performance are confirmed by experiments.