dcttceencode [-nl num_levels] [-ss stepsize] [-r rate] [-vo] [-os overlap_sample] [-sf smooth_factor] imgfile bitstream
dcttcedecode [-r rate] bitstream imgfile
dcttceencode codes an image, imgfile, using the DCT-TCE algorithm by Shah et al. The DCT-TCE algorithm combines a block-based lapped biorthogonal transform based on the DCT with the embedded TCE coder. See QccWAVdcttceEncode(3) for more detail on the DCT-TCE algorithm.
The -os and -sf control the overlapping and smoothing of the prefilter and postfilter that, when combined with a block-based DCT, form the lapped biorthogonal transform.
dcttceencode supports two encoding modes. Mode 1 consists of first applying a scalar quantizer to all DWT coefficients and then encoding the coefficients, bitplane by bitplane, until all bitplanes are encoded. Mode 2 consists of direct bitplane encoding without any scalar quantization of coefficients; in this mode, encoding stops when the target bitrate is reached. Mode 1 is selected by specifying a quantization stepsize with the -ss option. Mode 2 is selected by specifying a target encoding rate with the -r option. Note that one, and only one, of -ss and -r must be specified.
dcttceencode prints to stdout a small amount of information concerning the target bitrate and the actual bitrate achieved, as well as some run time information. Usually these rates are identical, but may differ slightly. If the -vo (value-only) option is given, all printed output is suppressed except for the actual bitrate.
dcttcedecode performs the corresponding decoding using the DCT-TCE algorithm, decoding the bitstream made by dcttceencode and producing a reconstructed image, imgfile. The -r option for dcttcedecode specifies the rate at which to stop decoding, which may be any rate less than that at which bitstream was originally produced.
dcttceencode and dcttcedecode call QccWAVdcttceEncode(3) and QccWAVdcttceDecode(3) , respectively, to perform DCT-TCE encoding and decoding. Refer to the man pages for these functions for more information on the details of the QccPack implementation of the TCE algorithm.
V. P. Shah, J. E. Fowler, and N. H. Younan, "Tarp Filtering of Block-Transform Coefficients for Embedded Image Coding," in Proceedings of the IEEE International Conference on Acoustics, Speech, and Signal Processing, Toulouse, France, May 2006, vol. 2, pp. 21-24.
Copyright (C) 1997-2021 James E. Fowler