Abstract: A method of compressing data is described in which the compressed data is generated by either or both of a primary compression unit or a reserve compression unit in order that a target compression threshold is satisfied. If a compressed data block generated by the primary compression unit satisfies the compression threshold, that block is output. However, if the compressed data block generated by the primary compression unit is too large, such that the compression threshold is not satisfied, a compressed data block generated by the reserve compression unit using a lossy compression technique, is output.

Abstract: Methods of encoding and decoding for video data are described for encoding or decoding coefficients for a transform unit. In particular, the sign bits for the non-zero coefficients are encoded using sign bit hiding. Two or more sets of coefficients are defined for the transform unit and a sign bit may be hidden for each set, subject to satisfaction of a threshold test. The sets may correspond to coefficient groups that are otherwise used in multi-level significance map encoding and decoding.

Abstract: An approach is provided for color clustering for preprocessing an image. A cross-product on values of pixels in a source image and a number of bits per channel is determined, rounded to integer values, and left aligned to specify a target image. The following actions are repeatedly performed until a count of colors in the target image equals a target: a least frequent color in the target image is identified, distances between the least frequent color and other colors in the target image are determined, a least distance among the distances is determined, where the least distance is between the least frequent color and a closest color, a merged color is generated by merging the least frequent color and the closest color, and the count of the colors in the target image is reduced by replacing the least frequent color and the closest color with the merged color.

Abstract: A method and system for producing a plant-based image includes receiving a source image; screening the source image into a set of picture elements; and producing raster data indicating at least a type or density of seeds or plants to plant for each picture element.

Abstract: Systems and methods of encoding display data include performing a part of a first predetermined transform algorithm on at least a first part of a first frame of display data, and analyzing a light level to determine whether a different transform algorithm would be more suitable for encoding a second part of the first frame of the display data. If it is determined that a different transform algorithm would be more suitable for encoding, the second part of the first frame of the display data is encoded using the different transform algorithm to generate an encoded first frame. If it is determined that a different transform algorithm would not be more suitable for encoding, the second part of the first frame of the display data is encoded using the first predetermined transform algorithm to generate the encoded first frame.

Abstract: A method of compressing data is described in which the compressed data is generated by either or both of a primary compression unit or a reserve compression unit in order that a target compression threshold is satisfied. If a compressed data block generated by the primary compression unit satisfies the compression threshold, that block is output. However, if the compressed data block generated by the primary compression unit is too large, such that the compression threshold is not satisfied, a compressed data block generated by the reserve compression unit using a lossy compression technique, is output.

Abstract: A data compression device and a compression method are provided. The data compression device includes a quantization table processing unit and a quantization unit. The quantization table processing unit determines a target quantization table in which a quantization coefficient satisfies a data distortion rate and a compression ratio of a preset condition according to a target compression ratio. By constructing different quantization tables for different data, a distortion rate is greatly reduced based on satisfying a compression ratio, and issues that the distortion rate and the compression ratio cannot be simultaneously satisfied in the prior art are alleviated.

Abstract: A method for decoding a bitstream representative of a picture is disclosed. Information representative of at least one encoding precision is first determined. A transform is then decoded responsive to the determined information. Finally, the picture is decoded using the decoded transform. A method for encoding a bitstream representative of a picture, as well as encoding devices and decoding devices are also disclosed.

Abstract: A method for non-uniform mapping for quantization matrix coefficients between different sizes of quantization matrices in image/video coding includes obtaining a first quantization matrix and identifying a second quantization matrix to be formed therefrom. The second quantization matrix is a factor of two larger than the first quantization matrix. The second quantization matrix is populated with values from the first matrix through non-uniform mapping of the first quantization matrix. Non-uniform mapping to populate the second quantization matrix includes directly mapping values of all or a portion of the first quantization matrix into a most upper left portion of the second quantization matrix and mapping up-sampling values of the first quantization matrix into a remaining portion of the second quantization matrix.

Abstract: The image coding method includes: determining a context for a current block to be processed, from among a plurality of contexts; and performing arithmetic coding on the control parameter for the current block to generate a bitstream corresponding to the current block, wherein in the determining: the context is determined under a condition that control parameters of neighboring blocks of the current block are used, when the signal type is a first type, the neighboring blocks being a left block and an upper block of the current block; and the context is determined under a condition that the control parameter of the upper block is not used, when the signal type is a second type, and the second type is one of “mvd_l0” and “mvd_l1”.

Abstract: A method for encoding video and an encoder for encoding video, a method for decoding video and a decoder for decoding video are provided. Accordingly, in one embodiment, a method for decoding video receives a bit-stream including a plurality of data units encoded according to a scan pattern comprising at least one U-pattern, and decodes a data unit among the plurality of data units by using at least one data unit included among the plurality of data units, the at least one other data unit being decoded prior to the data unit according to the scan pattern. When the plurality of data units are included in a data cluster, the method includes scanning the plurality of data units according to the at least one U-pattern, and the scanning includes scanning and decoding the data unit, followed by scanning and decoding a neighboring data unit horizontally or vertically adjacent to the data unit.

Abstract: The present invention relates to a method for decoding a video signal, comprising the steps of: acquiring a transform size flag of the current macroblock from a video signal; checking the number of non-zero transform coefficients at each pixel position in a first transform block which corresponds to the transform size flag; changing a scan order of the first transform block by prioritizing the position of the pixel having the greatest number of the non-zero transform coefficients in the first transform block; determining the number of the non-zero transform coefficients at each pixel position in a second transform block, and setting the changed scan order of the first transform block as an initialized scan order of the second transform block; adding the number of the non-zero transform coefficients at each pixel position in the first transform block and the number of the non-zero transform coefficients at each pixel position in the second transform block, and changing the scan order of the second transform bl

Abstract: The present disclosure generally relates to techniques for processing complex-valued array data representing an image. The techniques may include obtaining an electronic representation of an array of complex numbers representing an image, converting the array of complex numbers to an array of scaled coordinate pair values in a magnitude-phase plane, replacing each coordinate pair value with data representing a respective nearest node in a quantized magnitude-phase plane, such that an array of scaled quantized coordinate value pairs is produced, arranging into a sequence of bit values ordered according to decreasing bit significance, from most-significant bit values to least-significant bit values, the scaled quantized coordinate value pairs, and transmitting the sequence of bit values to a receiver, such that the receiver rearranges and rescales the sequence of bit values and obtains the image represented by the array of complex numbers.

Abstract: A video decoding apparatus using an intra-prediction, performs a method including: reconstructing information on an intra-prediction mode of a current block to be decoded from a bitstream, wherein the current block is a square block; reconstructing transform block information from the bitstream and reconstructing transform coefficients corresponding to each of one or more transform blocks divided in a quad tree structure from the current block; and reconstructing the current block based on the information on the intra-prediction mode and the reconstructed transform coefficients of the transform blocks.

Abstract: The present invention relates to a method for decoding a video signal, comprising the steps of: acquiring a transform size flag of the current macroblock from a video signal; checking the number of non-zero transform coefficients at each pixel position in a first transform block which corresponds to the transform size flag; changing a scan order of the first transform block by prioritizing the position of the pixel having the greatest number of the non-zero transform coefficients in the first transform block; determining the number of the non-zero transform coefficients at each pixel position in a second transform block, and setting the changed scan order of the first transform block as an initialized scan order of the second transform block; adding the number of the non-zero transform coefficients at each pixel position in the first transform block and the number of the non-zero transform coefficients at each pixel position in the second transform block, and changing the scan order of the second transform bl

Abstract: A video decoding apparatus using an intra-prediction, includes: a decoder configured to reconstruct information on an intra-prediction mode of a current block to be decoded from a bitstream, and reconstruct transform block information from the bitstream and reconstruct transform coefficients corresponding to each of one or more transform blocks divided in a tree structure from the current block; an inverse transformer configured to reconstruct residual signals by inversely transforming the transform coefficients corresponding to each of the transform blocks; a predictor configured to generate predicted pixels based on the information on the intra-prediction mode; and an adder configured to add the residual signals to the predicted pixels.

Abstract: Disclosed are a method of encoding a division block in video encoding and a method of decoding a division block in video decoding. An input picture is divided into encoding unit blocks. The encoding unit blocks are divided into sub-blocks. The sub-blocks are encoded by selectively using at least one of intra prediction encoding and inter prediction encoding. A decoding process is performed through a reverse process of the encoding method. When pixel values of an encoding unit block are encoded in video encoding, the flexibility in selecting an encoding mode is increased and the efficiency of encoding is increased.

Abstract: The present invention relates to a method for decoding a video signal, comprising the steps of: acquiring a transform size flag of the current macroblock from a video signal; checking the number of non-zero transform coefficients at each pixel position in a first transform block which corresponds to the transform size flag; changing a scan order of the first transform block by prioritizing the position of the pixel having the greatest number of the non-zero transform coefficients in the first transform block; determining the number of the non-zero transform coefficients at each pixel position in a second transform block, and setting the changed scan order of the first transform block as an initialized scan order of the second transform block; adding the number of the non-zero transform coefficients at each pixel position in the first transform block and the number of the non-zero transform coefficients at each pixel position in the second transform block, and changing the scan order of the second transform bl

Abstract: A method and apparatus for clipping a transform coefficient are disclosed. In one implementation, a method is implemented in a video encoder for clipping a quantization level. The method operates by generating the quantization level for a transform coefficient of a transform unit by quantizing the transform coefficient according to a quantization matrix and quantization parameter, determining a clipping condition in the video encoder based on video source bit-depth, and clipping the quantization level according to the clipping condition to generate a clipping-processed quantization level.

Abstract: A method and apparatus for decoding two-level scanned transform coefficients corresponding to a transform unit (TU) are disclosed. The TU is divided into sub-blocks and the transform coefficients of the TU are scanned across the sub-blocks according to a first scan pattern, and each sub-block is scanned according to a second scan pattern. In one embodiment, the sub-blocks of the transform coefficients received from the variable length decoding are stored in an inverse scan buffer (or TC buffer) and the transform coefficients are retrieved from the inverse scan buffer row-by-row or column-by-column in a selected direction after a corresponding row or column of the transform coefficients is fully received. In a system incorporating an embodiment of the present invention, at least a leading row or a leading column of the transform coefficients is available in the selected direction before a last sub-block of the transform coefficients arrives.

Abstract: Disclosed are a method of encoding a division block in video encoding and a method of decoding a division block in video decoding. An input picture is divided into encoding unit blocks. The coding unit (CU) blocks are divided into sub-CU blocks. The sub-CU blocks are encoded by selectively using at least one of intra prediction encoding and inter prediction encoding. A decoding process is performed through a reverse process of the encoding method. When pixel values of a CU block are encoded in video encoding, the flexibility in selecting an encoding mode is increased and the efficiency of encoding is increased.

Abstract: An image processing apparatus includes a receiving unit configured to receive image data of program content and genre information relating to the program content, a selection unit configured to select a size selection parameter for causing the genre information received by the receiving unit to be reflected in a block size, a determination unit configured to determine a block size in accordance with the size selection parameter selected by the selection unit, the block size being used for orthogonal transformation, and an orthogonal transformation unit configured to perform orthogonal transformation on the image data received by the receiving unit at the block size determined by the determination unit.

Abstract: An image processing system comprises an image processor configured to identify edges in an image, to apply a first type of filtering operation to portions of the image associated with the edges, and to apply a second type of filtering operation to one or more other portions of the image. By way of example only, in a given embodiment a clustering operation is applied to the image to identify a plurality of clusters, a first set of edges comprising edges of the clusters is identified, an edge detection operation is applied to the image to identify a second set of edges, a third set of edges is identified based on the first and second sets of edges, and the first type of filtering operation is applied to portions of the image associated with one or more edges of the third set of edges.

Abstract: Provided are a video encoding method and apparatus using a low-complexity transformation and a video decoding method and apparatus using a low-complexity inverse transformation. The video encoding method includes: receiving image data of an input picture in predetermined data units; generating coefficients of the predetermined data units by performing a low-complexity transformation on the image data; and outputting the generated coefficients. The low-complexity transformation includes at least one of a selective frequency-domain transformation that uses a transformation basis for a predetermined frequency-domain, a sub data unit transformation that performs a transformation by respectively selecting and applying transformation bases for a plurality of sub data units divided from the image data, and a scale-down transformation that uses a scale-down rectangular transformation basis that is a combination of a rectangular matrix and a square matrix.

Abstract: Some aspects of the disclosure relate to a compression technique that can permit determining dynamically a satisfactory quantization matrix based at least on properties intrinsic to a digital object being compressed and a predetermined compression quality criterion, wherein the quantization matrix is associated with a specific space-domain-to-frequency-domain transforms. In one aspect, the compression technique can permit creation of a compressed digital object that can satisfy a predetermined a compression quality criterion.

Abstract: Embodiments herein provide for a pre-processing stage or mechanism for enhancing data compression of an image by splitting or separating the color channels for pixels into planar data sources. Typically, image data is displayed as an interleaved set of channel types for a color space such that each pixel within an image (such as a bitmap) has one component for each color channel. By separating the interleaved bitmap into a planar representation, each plane can be compressed independently and often times achieve higher compression ratios. This is especially true for channels that are expected to stay fairly constant throughout the bitmap most of the time. The utilization of the above embodiment can be further enhanced through manipulation of channel data or through converting the color space from one form to another.

Abstract: The present invention relates to a method for storing an image sequence and a method for compressing, storing an image sequence. The method for storing an image sequence comprises the following steps: within the image sequence, forming a pixel-bit sequence according to known positions and order of each pixel in each of image frames formed by pixels; within the image sequence, setting a pixel value of a first pixel-bit position of a preceding image frame as a “preceding pixel value”, while setting the pixel value of the same pixel-bit position of the succeeding image frame adjacent to the said preceding image frame as a “succeeding pixel value”, comparing the said “preceding pixel value” with the said “succeeding pixel value”; creating a recording program to record a number of times of consecutively repeated presence of the “preceding pixel value” in the pixel-bit position.

Abstract: An approach is provided for implementing locked printing on a printing device with remote unlock. The printing device includes a locked print process that is configured to examine print data received by the printing device and determine whether locked printing is to be used for the print data. Print data designated for locked printing is stored on the printing device. The printing device also includes a Web application configured to generate Web pages that define a Web-based graphical user interface. When processed at a client device, the Web pages allow a user to enter authorization data that is transmitted to the Web application on the printing device. The locked print process verifies the authorization data and if the authorization data is successfully verified, allows the user access to locked print data on the printing device. The approach may also be implemented using a common repository to store print data.

Abstract: Embodiments herein provide for a pre-processing stage or mechanism for enhancing data compression of an image by splitting or separating the color channels for pixels into planar data sources. Typically, image data is displayed as an interleaved set of channel types for a color space such that each pixel within an image (such as a bitmap) has one component for each color channel. By separating the interleaved bitmap into a planar representation, each plane can be compressed independently and often times achieve higher compression ratios. This is especially true for channels that are expected to stay fairly constant throughout the bitmap most of the time. The utilization of the above embodiment can be further enhanced through manipulation of channel data or through converting the color space from one form to another.

Abstract: A system for and method of efficient interoperability assessment based on automated Behavioral Profiling and Emulation of SIP or T.38 Fax-relay Enabled Devices, for example, for profiling and emulating VoIP Phones such as SIP Phones, or T.38 Fax-relay devices such as Internet Aware Fax Terminals. The method includes a Multi-step/Multi-technology Iterative Profiling Stage that allows creating a Behavioral Profile based on the analysis of a plurality of traffic samples. Also, the method presents an efficient process of Device Emulation of an actual device to be used in interoperability assessment, including a Standard State Machine parameterized by a set of characteristics stored in the Behavioral Profile. The Emulation method can be used to duplicate one or more device behaviors exhibited either by different firmware revisions, software upgrades or by different OEM product models.

Abstract: A system and method for updating a display unit remotely located from a computing system are described. The method includes copying display information from a video buffer of a computing device executing an application to generate a display update, calculating a size of the display update, and determining an amount of available bandwidth of a network connecting the computing device and the display unit. The method also includes calculating a time period required to communicate the display update from the computing device to the display unit, transmitting the display update to the display; and repeating the method after the time period has elapsed.

Abstract: An apparatus and a method for performing video decoding processes in parallel are provided. The method is adapted for utilizing a first cluster and a second cluster of a processor to perform the video data decoding process in parallel. The method includes performing a VLD process to the video data with the first cluster, so as to obtain a plurality of coefficients and then performing an IZ process, an IQ process, and an IDCT process to the coefficients with the second cluster, so as to obtain a plurality of pixels values of the video data. When the first cluster decodes a coefficient of the video data, the second cluster performs the IZ, IQ, and IDCT processes to a coefficient previously decoded by the second cluster of the video data. Accordingly, a parallel process is realized and the decoding speed is increased.

Abstract: In an image encoder, a first quantization section which is selected when normal image quality is required performs quantization by dividing a wavelet transformation coefficient by a quantization step size and by thereafter rounding down a fraction thereof. On the other side, a second quantization section which is selected when high image quality is required performs quantization by dividing a wavelet transformation coefficient by a quantization step size, by adding 0.5 to the addition result, and by thereafter rounding down a fraction thereof. Therefore, the width of a dead zone where coefficients are quantized to a value of 0 is narrower than that in the first quantization section, and higher image quality is obtained accordingly.

Abstract: An Image Signal Processing unit (ISP) has at least one fixed-size line buffer which is smaller than the width of the image buffer. To handle the image data, the image buffer is divided into regions which are sequentially loaded into the at least one fixed-size line buffer of the ISP for processing. Since functions of the ISP operate with neighboring pixels of the target pixel, margins of the regions need to be transmitted as well. After processing by the ISP, the data is encoded which includes a DCT, Quantization, and VLC. The result is then stored in segments in a buffer storage. VLC also inserts a Restart Marker which is used as a pointer to stitch together all the segments thus producing a new and seamless image.

Abstract: Embodiments of the invention provide an instruction that computes the horizontal and vertical values (H,V) based upon the predefined equations. Based upon the horizontal and vertical values (H,V) and the current sign bit being processed at [m,n], the output context and decision pair (CX,D) is determined placed into a destination register.

Abstract: A content distribution mechanism that relies on cooperative desktop PCs to distribute content is disclosed. The mechanism distributes content in a robust manner by allowing at least one intermediate network node (i.e., between a source and client) to generate and send packets that contain a linear combination of the portions of content available at the node. Such linear combinations may be created by the source and client using at least a portion of the original content file in either encoded or unencoded form. After the client has received enough linearly independent combinations of packets, the original content may be reconstructed.

Abstract: Reduction in the blockiness of a simulated film grain block can be achieved either by the use of adaptive downscaling or adaptive deblocking filtering to adjust the intensity of the pixels at the block edge in accordance with at least one film grain block parameter, such as film grain size, intensity and texture. Performing such adaptive downscaling or adaptive deblocking filtering achieves improved performance at lower computational cost by avoiding modification of film grain block pixels in lesser affected areas.

Abstract: A method for compressing a digital image to be printed, the image consisting of pixels. It is determined, for blocks of pixels, whether a block contains a graphical structure that is to be maintained without loss because it is of a type that can be accurately perceived by a human observer. The block is encoded losslessly into a less voluminous format, if such a graphical structure has been found. Otherwise, the block is compressed lossily, if no such graphical structure has been found.

Abstract: The invention describes a process to prevent counterfeiting or alteration of a printed or engraved surface, characterized by the incorporation of a signature of the form of a digital mark into parts or the entire document, and in particular a digital mark technology to hide information in an invisible way through over-printing by using a method called asymmetric amplitude modulation. This method can be applied to any type of printed material such paper, packaging, or any other surface. Visible information can also be printed over the digital mark. As an application example, applied to a paper document the digital mark can be used to guarantee the document authenticity, as it would be destroyed by a copy process.

Abstract: A method of encoding a set of data representing physical quantities includes the steps of dividing the set of data into subsets, calculating a first encoding cost for each subset using a first encoding mode, calculating a second encoding cost for each subset using a second encoding mode, and selecting an encoding mode per subset as a function of the first and second encoding costs, in which the two encoding costs are calculated according to the same rate-distortion compromise (?), for the image overall.

Abstract: An Image Signal Processing unit (ISP) has at least one fixed-size line buffer which is smaller than the width of the image buffer. To handle the image data, the image buffer is divided into regions which are sequentially loaded into the at least one fixed-size line buffer of the ISP for processing. Since functions of the ISP operate with neighboring pixels of the target pixel, margins of the regions need to be transmitted as well. After processing by the ISP, the data is encoded which includes a DCT, Quantization, and VLC. The result is then stored in segments in a buffer storage. VLC also inserts a Restart Marker which is used as a pointer to stitch together all the segments thus producing a new and seamless image.

Abstract: Provided are an image processing apparatus and image processing method capable of processing image data as packet data, and compressing the image data in real time to a data amount within the storage capacity of a memory. Image data in the form of packet data is divided into a plurality of blocks by a block forming circuit (102), and compressed at a first compression ratio by a DCT circuit (104), quantizing circuit (105), and Huffman encoding circuit (106) for each block. A counter (108) measures the data amount of the compressed image data. If the measured data amount is equal to or larger than a predetermined value, the image data stored in a memory (112) is recompressed at a second compression ratio as a higher compression ratio by a Huffman decoding circuit (113), bit shifting circuit (114), and Huffman encoding circuit (115).

Abstract: In an image encoder, a first quantization section which is selected when normal image quality is required performs quantization by dividing a wavelet transformation coefficient by a quantization step size and by thereafter rounding down a fraction thereof. On the other side, a second quantization section which is selected when high image quality is required performs quantization by dividing a wavelet transformation coeffient by a quantization step size, by adding 0.5 to the dividing result, and by thereafter rounding down a fraction thereof. Therefore, the width of a dead zone where coefficients are quantized to a value of 0 is narrower than that in the first quantization section, and higher image quality is obtained accordingly.

Abstract: An apparatus and a method of changing a bit rate of a compressed image bit stream by changing a codeword so as to easily change the bit rate and reduce a changing loss. The apparatus for changing a bit rate, in which an input bit stream generated by an image compression encoding method is changed into an output bit stream having a desired bit rate, includes a changing codeword determiner which selects codewords to replace the codewords of the input bit stream, and a codeword changer which changes the codewords of the input bit stream into the codewords selected by the changing codeword determiner. The method and the apparatus can be applied to image services provided through the Internet and receiving apparatuses supporting the Personal Video Recorder (PVR) function. Particularly, the method of changing the bit rate of a compressed image bit stream changes the codewords of input transform coefficients so as to easily change the bit rate and reduce the changing loss.

Abstract: The present invention relates to an image capturing apparatus and method in which the image recording time is reduced and the memory capacity required for compression is also reduced. A number-of-bytes calculation unit 302 determines the number of bytes after compression based on an integrated value of high-frequency integrated data supplied from a high-frequency integration processor. Based on the determined number of bytes, a Q-scale calculation unit 303 determines a Q-scale based on which the image data can be compressed one time to a predetermined data size. A Q-table generation unit 304 generates a Q-table based on the Q-scale. A DCT unit 321 performs a discrete cosine transform on the input image data. A quantization processor 322 adjusts the compression ratio of the image data based on the up-to-date Q-table supplied from the Q-table generation unit 304.

Abstract: A method for encoding video with a two-dimensional (2D) transform separable to two one-dimensional (1D) transforms. The method receives an array of values for a sub-section of an image, performs a first 1D-transform of the array, transposes the resulting array, and performs a second 1D-transform of the array resulting from the transpose. The method, without performing another transpose, generates a data stream using a transposed scan order based on the values of the array resulting from the second transform. A method for decoding video encoded by a 2D transform, which separable to two 1D transforms. The method receives a data stream containing encoded values for an image, parses out the values into an array using a transposed scan order, performs a first 1D-inverse transform on the array, transposes the resulting array, and performs a second 1D-inverse transform of the array resulting from the transpose to produce a decoded output.

Abstract: JPEG data is efficiently recompressed and transmitted to a remote color facsimile device. Before transmission of recompressed JPEG data, an anticipated transmission time is displayed for enabling the user to easily select the desired compression ratio. To generate recompressed JPEG, a Huffman decoder is provided for decoding encoded data and temporarily generates decoded data. Table generator multiplies the predefined quantization table values by the prescribed value to generate the modified quantization table. Intermediate data generator generates the intermediate data by dividing the encoded data by ratio n, which is derived by dividing predefined quantization table by the modified quantization table. Huffman encoder encodes the intermediate data to create new encoded data. Recompressed JPEG data includes the newly coded data and the modified quantization table.

Abstract: The invention provides a system and method for JPEG encoding an image that includes variable quantization for each block, depending upon the classification of each block, which is dependent on the classification of pixels in that block.

Abstract: An image data generator for generating data on a size reduced image of an original image. In one embodiment, the image data generator includes: an inverse wavelet transform unit to perform on inverse wavelet transform on wavelet coefficients; and a coefficient selecting unit to select, of wavelet coefficients in a sub-band, wavelet coefficients to be subjected to the inverse wavelet transform. In one embodiment, the inverse wavelet transform unit performs the inverse wavelet transform only on the wavelet coefficients selected in the coefficient selecting unit with respect to the wavelet coefficients in the sub-band.

Abstract: In order to avoid print buffer under-run a printing method involves a printer printing a rendered first page of print data while another page is rendered in a connected computer. Simultaneously, a previously rendered page of print data is transmitted from the computer to the printer. Typically the connection between the computer and the printer is a relatively low bandwidth connection such as a USB, parallel port or 10 Base-T Ethernet connection. In order to rapidly transmit the rendered pages of print data across the low bandwidth connection the computer applies data compression to the print data.