摘要:
The invention relates to a method of encoding an input signal into an output bit stream (BS). Said method comprises steps of applying (1) a transformation to a block of values (BV) in order to get a transformed block (T), scanning (2) the coefficients (C1-C1) of a transformed block (TB) according to a coefficient scanning order, splitting (3) a scanned coefficient (Ci) into K groups of bits (Ci,1-Ci,K) such that at least a group of bits comprise at least 2 bits and such that said scanned coefficient (Ci) is the concatenation of the K groups of bits, entropy coding (4) a kth group of bits (Ci,k) using entropy codes into a kth entropy coded group of bits (ECi,k) and forming (5) a block bit stream (BBS) from the K entropy coded groups of bits of the scanned coefficients of the transformed block, said output bit stream (BS) comprising said block bit stream (BBS).
摘要:
The present invention relates to method for spatial up-scaling of an original video frame comprising p rows and q colums of pixels, where p and q are integers. Said up-scaling method comprises a step of constructing high-low (HL), low-high (LH), and high-high (HH) virtual spatial frequency subbands comprising p rows and q colums of pixels from the use of high-pass filtering of the original video frame, considered as a low-low spatial frequency subband (LL), in horizontal, vertical, and both directions, respectively. Said up-scaling method further comprises a step of applying an inverse wavelet transform (IWT) to the constructed subbands and to the original video frame in such a way that an up-sampled version of the original image is obtained.
摘要:
The versatile method of spatial and SNR scalable picture compression comprises: high resolution encoding (202a) an input picture (vi) yielding high resolution encoded data (coHR,LQ), being the base data; deriving a first down-scaled representative picture (p1) on the basis of the high resolution encoded data (coHR,LQ); deriving a second down-scaled representative picture (p2) on the basis of the input picture (vi); and lower resolution encoding (214) lower resolution quality enhancement data (coMR,MQ), usable for improving the visual quality of a picture reconstructable from the high resolution encoded data (coHR,LQ), on the basis of comparing the first down-scaled representative picture (p1) with the second down-scaled representative picture. This enables good bit-rate distribution for multi-resolution, multi-quality users.
摘要:
The invention relates to a transcoder (100) for a variable length coded data stream such as an MPEG 2 coded data stream transcoder (100) comprises a receiver (101) which receives the variable length coded data stream. The receiver (101) is connected to a significance processor (107) that determines if a variable length coded coefficient is significant or less significant. The significance processor (107) is connected to a truncation processor (111) which truncates the less significant coefficients. The trancoder further comprises an encode processor (109) which generates a transcoded data stream from the original significant coefficients and the truncated less significant coefficients. All processing may be performed exclusively in the variable length code domain thereby providing a low complexity and high speed transcoder.
摘要:
The present invention relates to a method of encoding blocks of values, e.g. DCT blocks, generated in accordance with an image compression scheme. The values are expressed as a set of bit planes, each bit plane comprising, for the values, all bits with a specific significance. In each bit plane at least one parameter is determined (7) in accordance with a predetermined definition, the parameter defining a partition of the bits in the bit plane which encloses all set bits. All bits in the partition are transferred (8) to a bit stream that may be truncated. This provides a method with low complexity. The invention further relates to a corresponding encoding device, a corresponding decoding device, and a corresponding bit-stream.
摘要:
The invention relates to a signal processing system comprising first electronic means for storing an input signal, second means for a real-time processing of the input signal thus stored, and third electronic means for storing the signal thus processed. This system is according to the invention, characterized in that said second processing means themselves comprise off-line signal enhancement means applied to said input signal and using available processing resources, not still used for real-time or on-line processing, for delivering an enhanced signal and storing it in said third means for storing the signal processed by the second processing means. The signal enhancement means may also comprise means for modifying said enhanced signal, said third electronic means for storing the processed signal being also able to store the enhanced signal thus modified, and the third electronic means for storing the signal processed may be provided for outputting the enhanced signal and/or the modified enhanced signal in real time.
摘要:
A heterogeneous layered video decoding system and associated method is disclosed that provides for flexible and cost effective scalability through the use of generic decoders (e.g., MPEG-2/4/AVC) at each layer instead of decoders specifically designed for scalable systems. In one embodiment, additional signaling information (220) embodied as a parameter list is transmitted along with the transport stream (250). The parameter list independently defines for each layer (BS, ES), how the particular layer is to be decoded. In this manner, a trade-off between complexity and efficiency is achieved. For example, the base layer (BS) may employ a sophisticated base layer AVC codec, while one or more enhancement layers (ES) may use an MPEG-2 codec that is half as complex as a full AVC codec but only slightly less efficient.
摘要:
The invention relates to a method of coding video data available in the form of a first input stream of video frames, and to a corresponding coding device. This method, implemented for instance in three successives stages (101, 102, 103), comprises the steps of (a) encoding said first input stream to produce a first coded base layer stream (BL1) suitable for a transmission at a first base layer bitrate; (b) based on said first input stream and a decoded version of said encoded first base layer stream, generating a first set of residual frames in the form of a first enhancement layer stream and encoding said stream to produce a first coded enhancement layer stream (EL1); and (c) repeating at least once a similar process in order to produce further coded base layer streams (BL2, BL3, . . . ) and further coded enhancement layer streams (EL2, EL3, . . . ). The first input stream is thus, for obtaining a required spatial resolution, compressed by encoding the base layers up to said spatial resolution with a lower bitrate and allocating a higher bitrate to the last base layer and/or to the enhancement which corresponds to said required spatial resolution. A corresponding transmission method is also proposed.
摘要:
The versatile method of spatial and SNR scalable picture compression comprises: high resolution encoding (202a) an input picture (vi) yielding high resolution encoded data (coIIR,LQ), being the base data; deriving a first down-scaled representative picture (p1) on the basis of the high resolution encoded data (coHR,LQ); deriving a second down-scaled representative picture (p2) on the basis of the input picture (vi); and lower resolution encoding (214) lower resolution quality enhancement data (coMR,MQ), usable for improving the visual quality of a picture reconstructable from the high resolution encoded data (coIIR,LQ), on the basis of comparing the first down-scaled representative picture (p1) with the second down-scaled representative picture. This enables good bit-rate distribution for multi-resolution, multi-quality users.
摘要:
The present invention relates to a method of encoding blocks of values, e.g. DCT blocks, generated in accordance with an image compression scheme. The values are expressed as a set of bit planes, each bit plane comprising, for the values, all bits with a specific significance. In each bit plane at least one parameter is determined (7) in accordance with a predetermined definition, the parameter defining a partition of the bits in the bit plane which encloses all set bits. All bits in the partition are transferred (8) to a bit stream that may be truncated. This provides a method with low complexity. The invention further relates to a corresponding encoding device, a corresponding decoding device, and a corresponding bit-stream.