Showing papers on "Run-length encoding published in 1996"

Run-based algorithms for binary image analysis and processing

Abstract: In this paper we suggest a variant of a binary image representation based on run length encoding. This variant allows one to build a "graph representation" for a number of computing tasks like component labeling, computations of Euler number, diameter and convex hull, and the detection of local extrema and multiple points. Finally, a running application in the raster-to-vector conversion of digital maps is provide.

Video display system

Abstract: PROBLEM TO BE SOLVED: To provide a wireless video display system which excels in portability and ensures the smooth movements of the moving image parts and the clear reproduction of the static image parts by comparing only the video signals of different parts with each other between the continuous front and rear frames of video signals and decoding the video signals which are encoded and transmitted. SOLUTION: In regard to the inputted RGB signals, an encoding circuit 12 of a transmitting device 2 compares the video signals with each other between the preceding and next screens and only the parts having changes on both screens are selectively and reversibly encoded and outputted in a run length encoding system. At the same time, the encoding rate is regulated according to the decoding state of a decoding circuit 24 of a display device 3 or the video signals are retransmitted. The data to be transmitted include the control data on the encoding conditions, etc., in addition to the graphic data, and the device 3 writes the encoded graphic data in a memory 25 based on the control data. Then a read control circuit 27 reads out the data, and the RGB signals converted into the analog signals by a DA converter 26 are shown on a display 32 as images.

FIFO feedback and control for digital video encoder

Abstract: Method and apparatus for encoding a digital video image stream in an encoder. The encoding includes spatial compression of still images in the digital video image stream and temporal compression between the still images. The spatial compression is carried out by converting a time domain image of a macroblock to a frequency domain image of the macroblock, taking the discrete cosine transform of the frequency domain image, transforming the discrete cosine transformed macroblock image by a quantization factor, and run length encoding the quantized discrete cosine transformed macroblock image. The temporal compression is carried out by reconstructing the run length encoded, quantized, discrete cosine transformed image of the macroblock, searching for a best match macroblock, and constructing a motion vector between them. This forms a bitstream of runlength encoded, quantized, discrete cosine transformed macroblocks and of motion vectors. This bitstream is passed to and through a FIFO buffer to a transmission medium. The number of run length encoded bits is fed back to the encoder for calculation of the quantization factor, to thereby avoid overrunning the buffer and interrupting the transmission.

Method and apparatus for double run-length encoding of binary data

Abstract: A method and apparatus for losslessly compressing binary data using a technique referred to as Double Run-Length Encoding (DRLE). DRLE has particular application to the compression of gray-scale data as it is being processed for printing by a laser printer or other continuous raster scan device. DRLE records repeating patterns of ones and zeros with little computational complexity. Compression ratios that may be an order of magnitude or more are obtained frequently on data that may not compress well using traditional Run-Length Encoding (RLE). DRLE uses a sequential history of order-pairs that denote variable-length patterns of zeros and ones, and then encodes these patterns as they repeat themselves.

Method and apparatus for run-length encoding using special long-run codes

Abstract: Magnitudes of runs of constant signal value in signals representative of physical activities or objects are determined. The signals are converted to fixed-length run-length (RL) codes, wherein each long run in the signals that is longer than the largest run length represented by a single RL code is represented by at least one no-change RL code and an RL code representing a remainder value, wherein the no-change RL code represents a portion of the long run and also indicates that the immediately following RL code corresponds to a continuation of the long run. In a preferred embodiment, binary images are run-length encoded and the resulting run-length codes are subjected to variable-length encoding using structured Huffman tables.

Image compression and decompression using predictive coding and error diffusion

Abstract: An encoding/compression technique using a combination of predictive coding and run length encoding allows for efficient compression of images produced by error diffusion.

Run-length coding method

Abstract: PROBLEM TO BE SOLVED: To provide a method for realizing efficient run length encoding by shortening a run length in the scanning of a DCT coefficient block. SOLUTION: The block of a transformation coefficient is divided into plural sub blocks and whether or not at least one non-zero value is present inside the respective sub blocks is judged. By detecting 104 a sub block array composed of the sub blocks provided with the non-zero value, scanning the entire transformation coefficients present inside the non-zero blocks by a predetermined scanning sequence and performing the run length encoding 113, run length encoded signals are generated.

Method and apparatus for quantizing and run length encoding transform coefficients in a video coder

Abstract: A method and apparatus for run length encoding video data for transform based coders. The video data is separated into blocks of pixels. The pixel values are transformed to another set of values which can be represented with less data. The transformed values are quantized by generating a quantized magnitude and sign for multiple transformed values at a time, while removing branch misprediction errors during the quanitizing process. The quantized values are run length encoded by removing branch misprediction errors during the encoding process.

Image signal encoding method and device therefor and image signal decoding method and device therefor

Abstract: PROBLEM TO BE SOLVED: To efficiently encode the coefficient of a wavelet conversion in a sub-band encoding. SOLUTION: An adder 1 generates an anticipated error signal, and a wavelet converter 20 preforms a wavelet conversion for the anticipated error signal and divides the signal into the signals of plural frequency bands. A quantizer 2 quantizes a conversion coefficient, and a frame memory 3 temporarily stores the quantization coefficient, extracts the coefficients existing at the same spatial location at each hierarchy obtained by a band division, generates a coefficient tree, performs an S-scan for the coefficient tree from a low frequency band to a high frequency band and generates a scan string. A run length encoding device 4 performs a run length encoding for this scan string and generates encoding data A variable length encoding/multiplexing device 6 performs a variable length encoding for encoding data, multiplexes the data and transmits the data.

Digital image compression system

Abstract: The digital image compression system compares current and preceding digital images on a pixel-by-pixel basis using an exclusive-or operation to identify the differences therebetween. The result of the exclusive-or operation between the two images is then compressed using a loss-less compression algorithm (e.g. run length encoding) for subsequent processing or storage. Compression of selected portions of the current and preceding image is also disclosed.

Video coder and decoder

Abstract: The method involves generating coding transformation coefficients in a forward path (VP) using a coding transformation (DCT). A scanning procedure (SV) is applied to the generated coefficients in the forward path of the coding and decoding unit (CD), and the scanned coefficients undergo a quantisation in a quantiser (Q). A run length encoding (RLC) is performed in the forward path. A run length decoding (RLD) is performed in a reconstruction path (RP), at the beginning of a internal reconstruction of the video data stream. An inverse quantisation (IQ) is performed on the run-length decoded data, and the produced data undergo a process (ISV) which is an inverse of the scanning procedure. The resulting data undergo an inverse coding transformation (IDCT) and the resulting, reconstructed video data stream is subtracted from the original video data stream, to form only the difference for processing.

Data compression device

Abstract: PURPOSE: To provide a data compression device which can easily and highly precisely compress character data CONSTITUTION: A character data conversion part 1 converts input character data into a binary code, and a parallel/serial conversion part 3 serially converts it It is written into N-bit length shift registers 4 to 7 Selection circuits 8 to 10 sequentially read data at the code number interval of the binary code constituting character data Data which are read are serially converted in a parallel/ serial conversion circuit 11 and are compressed in a run length encoding part 12