WO2003105070A1 - Spatial prediction based intra coding - Google Patents

Spatial prediction based intra coding Download PDF

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Publication number
WO2003105070A1
WO2003105070A1 PCT/IB2003/002202 IB0302202W WO03105070A1 WO 2003105070 A1 WO2003105070 A1 WO 2003105070A1 IB 0302202 W IB0302202 W IB 0302202W WO 03105070 A1 WO03105070 A1 WO 03105070A1
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Prior art keywords
prediction modes
prediction
group
mode
modes
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PCT/IB2003/002202
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French (fr)
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Marta Karczewicz
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Nokia Corporation
Nokia Inc.
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=29741013&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=WO2003105070(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Priority claimed from US10/171,467 external-priority patent/US20030231795A1/en
Application filed by Nokia Corporation, Nokia Inc. filed Critical Nokia Corporation
Priority to KR1020047020114A priority Critical patent/KR101017094B1/en
Priority to EP03732786.3A priority patent/EP1512115B1/en
Priority to CA2488266A priority patent/CA2488266C/en
Priority to JP2004512067A priority patent/JP4490261B2/en
Priority to MXPA04012133A priority patent/MXPA04012133A/en
Priority to AU2003240172A priority patent/AU2003240172B2/en
Publication of WO2003105070A1 publication Critical patent/WO2003105070A1/en

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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/41Bandwidth or redundancy reduction
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/46Embedding additional information in the video signal during the compression process
    • H04N19/463Embedding additional information in the video signal during the compression process by compressing encoding parameters before transmission
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06VIMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V10/00Arrangements for image or video recognition or understanding
    • G06V10/20Image preprocessing
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/46Colour picture communication systems
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/102Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or selection affected or controlled by the adaptive coding
    • H04N19/103Selection of coding mode or of prediction mode
    • H04N19/105Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/102Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the element, parameter or selection affected or controlled by the adaptive coding
    • H04N19/103Selection of coding mode or of prediction mode
    • H04N19/11Selection of coding mode or of prediction mode among a plurality of spatial predictive coding modes
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/169Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding
    • H04N19/17Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object
    • H04N19/176Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a block, e.g. a macroblock
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/189Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding
    • H04N19/196Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding being specially adapted for the computation of encoding parameters, e.g. by averaging previously computed encoding parameters
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/10Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding
    • H04N19/189Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding
    • H04N19/196Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding being specially adapted for the computation of encoding parameters, e.g. by averaging previously computed encoding parameters
    • H04N19/197Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the adaptation method, adaptation tool or adaptation type used for the adaptive coding being specially adapted for the computation of encoding parameters, e.g. by averaging previously computed encoding parameters including determination of the initial value of an encoding parameter
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N19/00Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
    • H04N19/50Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding
    • H04N19/593Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving spatial prediction techniques

Definitions

  • the present invention relates generally to image coding and, more particularly, to coding blocks of video frames.
  • a digital image such as a video image, a TV image, a still image or an image generated by a video recorder or a computer, consists of pixels arranged in horizontal and vertical lines.
  • the number of pixels in a single image is typically in the tens of thousands.
  • Each pixel typically contains luminance and chrominance information.
  • JPEG, MPEG and H.263 standards have been developed.
  • the frame of the original video sequence is partitioned into rectangular regions or blocks, which are encoded in Intra-mode (I-mode) or Inter-mode (P-mode).
  • the blocks are coded independently using some kind of transform coding, such as DCT coding.
  • transform coding such as DCT coding.
  • pure block-based coding only reduces the inter-pixel correlation within a particular block, without considering the inter-block correlation of pixels, and it still produces high bit-rates for transmission.
  • Current digital image coding standards also exploit certain methods that reduce the correlation of pixel values between blocks.
  • blocks encoded in P-mode are predicted from one of the previously coded and transmitted frames.
  • the prediction information of a block is represented by a two-dimensional (2D) motion vector.
  • the predicted block is formed using spatial prediction from already encoded neighboring blocks within the same frame.
  • the prediction error i.e., the difference between the block being encoded and the predicted block is represented as a set of weighted basis functions of some discrete transform.
  • the transform is typically performed on an 8x8 or 4x4 block basis.
  • the weights - transform coefficients - are subsequently quantized.
  • Quantized transform coefficients together with motion vectors and some control information, form a complete coded sequence representation and are referred to as syntax elements.
  • syntax elements Prior to transmission from the encoder to the decoder, all syntax elements are entropy coded so as to further reduce the number of bits needed for their representation.
  • the block in the current frame is obtained by first constructing its prediction in the same manner as in the encoder and by adding to the prediction the compressed prediction error.
  • the compressed prediction error is found by weighting the transform basis functions using the quantized coefficients.
  • the difference between the reconstructed frame and the original frame is called reconstruction error.
  • the compression ratio i.e., the ratio of the number of bits used to represent the original and compressed sequences, both in case of I- and P- blocks, is controlled by adjusting the value of the quantization parameter that is used to quantize transform coefficients.
  • the compression ratio also depends on the employed method of entropy coding.
  • FIG. 2 An example of spatial prediction used in a Working Draft Number 2 (WD2) of the JVT coder is described as follows.
  • the JVT coder offers 9 modes for prediction of 4x4 blocks, including DC prediction (Mode 0) and 8 directional modes, labeled 1 through 7, as shown in Figure 1.
  • the prediction process is illustrated in Figure 2.
  • the pixels from a to p are to be encoded, and pixels A to Q from neighboring blocks that have already been encoded are used for prediction. If, for example, Mode 1 is selected, then pixels a, e, i and m are predicted by setting them equal to pixel A, and pixels b, f, j and n are predicted by setting them equal to pixel B, etc.
  • Mode 1 is a predictor in the vertical direction
  • Mode 2 is a predictor in the horizontal direction.
  • - e, f, g, h are predicted by F
  • i, j, k, 1 are predicted by G
  • - m, n, o, p are predicted by H.
  • This mode is used only if all A, B, C, D, I, J, K, L, Q are inside the picture. This is a "diagonal" prediction.
  • - a is predicted by (A + 2B + C + I + 2J + K + 4)»3 - b, e are predicted by (B + 2C + D + J + 2K + L + 4)»3
  • This mode is used only if all A, B, C, D, I, J, K, L, Q are inside the picture. This is a "diagonal" prediction. - a, j are predicted by (Q + A + 1)»1
  • This mode is used only if all A, B, C, D, I, J, K, L, Q are inside the picture. This is a "diagonal" prediction.
  • Vahteri et al. discloses a block-based coding method wherein directionality information of the image within the blocks are used to classify a plurality of spatial prediction modes.
  • the spatial prediction mode of a block is determined by the directionality information of at least one neighboring block.
  • an example of the prediction modes for the block C is given when the prediction mode for both U and L is 2.
  • the string (2, 8, 7, 1, 0, 6, 4, 3, 5) indicates that mode 2 is also the most probable mode for block C.
  • Mode 8 is the next most probable mode, etc.
  • the ordering of the modes for block C can also be specified by listing the rank for each mode: the higher the rank, the less probable the prediction method. For the above example, the rank list would be (5, 4, 1, 8, 7, 9, 6, 3, 2).
  • the modes (0, 1, 2, 3, 4, 5, 6, 7, 8) are related to the rank list (5, 4, 1, 8, 7, 9, 6, 3, 2), we can tell that Mode 0 has a rank 5, Mode 1 has a rank 4, etc.
  • a method and device for coding a digital image using intra-mode block prediction is provided.
  • a list of prediction modes for each combination of prediction modes of the neighboring blocks is obtained.
  • the modes assigned to each combination of prediction modes may be divided into two groups.
  • the first group includes m (where m is smaller than the overall number n of available modes) most probable prediction modes and the second group includes the remaining modes.
  • the modes in the first group are ordered according to their probability. This order may be specified as a list of modes ordered from most probable to the least probable mode.
  • the modes belonging to the second group may be ordered in some predetermined manner, which may be specified depending on the information already available to the decoder. Information is sent to the decoder regarding whether the mode selected for a given block belongs to the first group or to the second group.
  • the information is transmitted indicating that rth most probable mode shall be used for a block C given the combination of modes for blocks U and L. If the mode belongs to the second group, the information is transmitted indicating thaty ' th mode of this group should be used.
  • Figure 1 is a schematic representation illustrating 8 directional modes that are used as spatial prediction modes.
  • Figure 2 is a schematic representation illustrating the pixels that are used for the prediction of a current 4x4 block of pixels.
  • Figure 3 is a schematic representation illustrating two neighboring blocks being used for the prediction of a current block.
  • Figure 4a is a schematic representation illustrating the spatial prediction mode of two neighboring blocks used for the prediction of a current block.
  • Figure 4b is a schematic representation illustrating the spatial prediction mode of two neighboring blocks having a mirrored relationship with those of Figure 4a.
  • Figure 5a is a schematic representation illustrating another spatial prediction mode pair.
  • Figure 5b is a schematic representation illustrating the mirrored mode pair.
  • Figure 6 is a flow-charting illustrating the method of spatial prediction.
  • Figure 7 is a block diagram illustrating a digital image block transfer system for implementing the method according to an embodiment of the present invention.
  • Figure 8 is a block diagram illustrating a portable video telecommunications device implementing the method according to an embodiment of the present invention.
  • An embodiment of the present invention utilizes the property that it is possible to obtain an ordered list of prediction modes for one combination of prediction modes of neighboring blocks as a function of prediction modes for another combination.
  • prediction modes of two neighboring blocks U and L are used to infer the prediction of the current block C.
  • a combination of prediction modes in Figure 4a can be obtained by flipping diagonally the prediction modes, as shown in Figure 4b. Accordingly, the nth most probable prediction mode for block C, when the combination of modes in Figure 4a is used, should be the same as the "flipped diagonally", ntb-most-probable prediction mode for the combination of modes in Figure 4b.
  • the ordered list of prediction modes for ⁇ k,l) can be substantially symmetrical to that for ⁇ ij).
  • the primary objective of the present invention is to reduce the size of the table specifying prediction mode as a function of prediction modes of already coded, neighboring blocks (e.g., TABLE I). This table is obtained during the training process.
  • the number each prediction mode is chosen according to a given selection criterion e.g., the smallest prediction error
  • This number determines the rank of prediction mode in the list of prediction modes assigned to combination (ij), more frequently the mode is chosen, higher the rank it has in the list of prediction modes.
  • the resulting table specifying prediction modes will be smaller. If the ordered list for combination (k,l) can be obtained from ordered list for combination (ij) only the Attorney Docket No. 944-001.078-4-1
  • the reduced prediction table is shown in TABLE III.
  • the former can be eliminated.
  • the second group of elements in a prediction table comprising a first group of elements and a second group of elements, wherein each of the second group of elements can be restored from a corresponding element in the first group by a mapping function, the second group of elements can be eliminated.
  • Figure 6 is a flowchart illustrating the decoding stage when the symmetry in the prediction table is utilized.
  • the method 100 comprises receiving a plurality of image blocks at step 110.
  • the complementary prediction mode of the current block is mapped into the prediction mode of the current block.
  • modes 1, 5 and 6 can be grouped together and labeled as 1
  • modes 2, 7 and 8 can be grouped together and labeled as 2.
  • the directions of modes 7 and 8 are close to the direction of mode 2
  • the directions of modes 5 and 6 are close to the direction of mode 1.
  • each of blocks U and L can have one of the 5 modes labeled as 0, 1, 2, 3 and 4. Therefore, instead of 9x9 possible combinations of prediction modes of U and L, there are only 5x5 such combinations.
  • the memory required to specify ordering of prediction modes for block C will be 5x5x9 bytes, instead of 9x9x9 bytes (assuming that 1 byte of memory is required to hold 1 number).
  • the mapping function/is used for "flipping" the ordered lists the prediction table can be further simplified.
  • An example of the table specifying prediction mode as a function of ordering signaled in the bitstream when both of these methods are used in conjunction is given in TABLE IV.
  • the spatial, prediction-based intra-coding can be readily incorporated into a digital, image-block transfer system, as shown in Figure 7.
  • encoding of the frame proceeds as follows.
  • the blocks of the frame to be coded are directed one by one to the encoder 50 of the video transfer system presented in Figure 7.
  • the blocks of the frame are received from a digital image source, e.g. a camera or a video recorder (not shown) at an input 27 of the image transfer system.
  • the blocks received from the digital image source comprise image pixel values.
  • the frame can be stored temporarily in a frame memory (not shown), or alternatively, the encoder receives the input data directly block by block.
  • the blocks are directed one by one to a prediction method selection block 35 that determines whether the pixel values of the current block to be encoded can be predicted on the basis of previously intra-coded blocks within the same frame or segment.
  • the prediction method selection block 35 receives input from a frame buffer of the encoder 33, which contains a record of previously encoded and subsequently decoded Attorney Docket No. 944-001.078-4-1
  • the prediction method selection block can determine whether prediction of the current block can be performed on the basis of previously decoded and reconstructed blocks. Furthermore, if appropriate decoded blocks are available, the prediction method selection block 35 can select the most appropriate method for predicting the pixel values of the current block, if more than one such method may be chosen. It should be appreciated that in certain cases, prediction of the current block is not possible because appropriate blocks for use in prediction are not available in the frame buffer 33. In the situation where more than one prediction method is available, information about the chosen prediction method is supplied to multiplexer 13 for further transmission to the decoder. It should also be noted that in some prediction methods, certain parameters necessary to perform the prediction are transmitted to the decoder.
  • Pixel values of the current block are predicted in the intra prediction block 34.
  • the intra prediction block 34 receives input concerning the chosen prediction method from the prediction method selection block 35 and information concerning the blocks available for use in prediction from frame buffer 33. On the basis of this information, the intra prediction block 34 constructs a prediction for the current block.
  • the predicted pixel values for the current block are sent to a differential summer 28 which produces a prediction error block by taking the difference between the pixel values of the predicted current block and the actual pixel values of the current block received from input 27.
  • the error information for the predicted block is encoded in the prediction error coding block in an efficient form for transmission, for example using a discrete cosine transform (DCT).
  • the encoded prediction error block is sent to multiplexer 13 for further transmission to the decoder.
  • the encoder of the digital image transmission system also includes decoding functionality.
  • the encoded prediction error of the current block is decoded in prediction error decoding block 30 and is subsequently summed in summer 31 with the predicted pixel values for the current block. In this way, a decoded version of the current block is obtained.
  • the decoded current block is then directed to the frame buffer 33.
  • a demultiplexer receives the demultiplexed coded prediction error blocks and prediction information transmitted from the encoder 50.
  • the prediction information may include parameters used in the prediction process. It should be appreciated that in the case that only one intra prediction method is used, information concerning the prediction method used to code the blocks is unnecessary, although it may still be necessary to transmit parameters used in the prediction process. In Figure 7, dotted lines are used to represent the optional transmission and reception of prediction method information and/or prediction parameters. Assuming more than one intra prediction method may be used, information concerning the choice of prediction method for the current block being decoded is provided to intra prediction block 41.
  • Intra prediction block 41 examines the contents of frame buffer 39 to determine if there exist previously decoded blocks to be used in the prediction of the pixel values of the current block. If such image blocks exist, intra prediction block 41 predicts the contents of the current block using the prediction method indicated by the received prediction method information and possible prediction-related parameters received from the encoder. Prediction error information associated with the current block is received by prediction error decoding block 36, which decodes the prediction error block using an appropriate method. For example, if the prediction error information was encoded using a discrete cosine transform, the prediction error decoding block performs an inverse DCT to retrieve the error information. The prediction error information is then summed with the prediction for the current image block in summer 37 and the output of the summer is applied to the frame buffer 39.
  • each block is decoded, it is directed to the output of the decoder 40, for example, to be displayed on some form of display means.
  • the image frame may be displayed only after the whole frame has been decoded and accumulated in the frame buffer 39.
  • the intra-prediction block 34 constructs a prediction of the current block based on the previously encoded and subsequently decoded and reconstructed intra blocks as provided by the frame buffer 33.
  • the prediction of the current block is determined from the spatial prediction modes of the previously reconstructed intra blocks using a prediction table, as shown in TABLE III or TABLE IV (not shown in Figure 7).
  • a prediction table as shown in TABLE III or TABLE IV (not shown in Figure 7).
  • the ordered list for the prediction Attorney Docket No. 944-001.078-4-1
  • a mapping block 32 can be used to map the spatial prediction modes of the previously reconstructed blocks into complementary or mirrored spatial prediction modes ⁇ k,l).
  • the intra prediction block 34 can determine the complementary or mirrored prediction modefp) for the current block. Again the mapping block 32 is used to obtained the prediction mode/? of the current block by mapping the complementary prediction modefp). Likewise, a mapping block 38 is used for mapping when needed.
  • the mapping algorithm which is used to perform the mapping of ⁇ ij) to ⁇ k,l) and the mapping offlp) to p, can be coded in a software program 69, which comprises machine executable steps or pseudo codes for performing the method according to the present invention.
  • the software program is stored in a storage medium.
  • the software program is stored in a memory unit resident in a CPU 70, or in a separate memory unit 68, as shown in Figure 8.
  • Figure 8 presents a simplified schematic diagram of a mobile terminal 90 intended for use as a portable video telecommunications device, incorporating the prediction mode mapping method of the present invention.
  • the mobile terminal 90 comprises at least a display module 76 for displaying images, an image capturing device 72, and an audio module 74 for capturing audio information from an audio input device 82 and reproducing audio information on an audio producing device 80.
  • the mobile terminal 90 further comprises a keyboard 78 for inputting data and commands, a radio frequency component 64 for communicating with a mobile telecommunications network and a signal/data processing unit 70 for controlling the operation of the telecommunications device.
  • the digital image block transfer system (50, 60) is implemented within in the processor 70.
  • memory requirements could be limited while achieving coding efficiency.
  • the modes assigned to each combination of prediction modes of U and L may be divided into two groups.
  • the first group includes m (where m is smaller than the overall Attorney Docket No. 944-001.078-4-1
  • the modes in the first group are ordered according to their probability. As described above, this order may be specified as a list of modes ordered from most probable to the least probable mode.
  • the modes belonging to the second group may be ordered in some predetermined manner, which may be specified depending on the information already available to the decoder. For example, prediction mode that is labeled using smaller number may precede prediction mode that is labeled using larger number.
  • the prediction modes are arranged into an ordered set S.
  • the modes in the first ordered set T are ordered according to their expected probability of occurrence for combination of modes for neighboring blocks U and L. The more frequently the mode is expected to occur, the fewer bits should be used to signal it.
  • the second ordered set of modes is created by removing elements of the first set from the set S and preserving the order of the remaining elements. For example, if prediction i preceded prediction mode / in the ordered set S, prediction i should precede prediction mode j in the set V.
  • Mode 1 constitutes the first ordered set T.
  • the decoder receives the information that first group is selected, no further information is required since only one mode belongs to this group. If the mode belongs to the second group, the information is transmitted indicating thaty ' th mode of this group should be used. In our exemplar, if the information is received that the first mode should be selected, mode 0 should be chosen.
  • the way that the elements of the first set T are specified depends on the prediction modes of neighboring blocks U and L.
  • the elements of this set can be specified for example as a table stored in the memory both of the encoder and decoder, or they can be inferred from the modes U and L themselves.
  • the signaling to the decoder of which mode is selected can be done in numerous ways, for example:
  • the information about the rank of the prediction mode in the ordered set R can be transmitted.
  • the same label may be assigned to different prediction modes of blocks U and L before using them to specify prediction mode for block C.
  • Diagonal modes 3, 5 and 8 are grouped together and labeled as 3
  • diagonal modes 4, 6 and 7 are grouped together and labeled as 4.
  • each of blocks U and L may have one of the 5 modes labeled as 0, 1, 2, 3 and 4. Therefore, instead of 9x9 possible combination of prediction modes of U and L there are only 5x5 such combinations.
  • First information is sent to the decoder whether the most probable mode is used. This information is coded jointly for two 4x4 blocks as given in table below.
  • X denotes that the most probable mode should be used.
  • the code number from 0 to 7 is transmitted indicating which of the remaining modes should be used. Since the remaining modes are ordered according to their number, the mode with a smaller number precedes the mode with a higher number, when the code number q is received, the used prediction mode is equal to:
  • the code number q is sent as 3-bit codeword, which is the binary representation of the corresponding code number.
  • the present invention provides methods, devices and systems for coding into a bitstream and decoding from the bitstream image information comprising a plurality of image blocks using a plurality of spatial prediction modes for intra-mode block prediction.
  • the spatial prediction mode of a current block (C) can be determined based on a plurality of derived prediction modes, derived from the spatial prediction modes of a plurality of neighboring blocks (U, L) of the current block (C).
  • the plurality of n derived prediction modes are grouped into a first group of m first prediction modes with m ⁇ n and a second group of second prediction modes.
  • the first prediction modes have a higher probability of occurrence than the second prediction modes.
  • the second prediction modes are arranged in a predetermined fashion known to the decoder.
  • an ordered set is provided to the decoding device so as to allow the decoding device to determine the order of the second prediction modes based on the provided ordered set.
  • the ordered set is associated with one or more group of the spatial prediction modes of the neighboring blocks (U, L) of the current block (C).
  • the bitstream may include coded information indicative of which of the first prediction modes has the highest probability of occurrence when the derived prediction mode with the highest probability of occurrence is selected for use in coding the current block (C).
  • the present invention also provides a computer program having pseudo codes for use in grouping the plurality of derived prediction modes into the first and second groups, and in ordering the first prediction modes according to the probability of occurrence among the first prediction modes.

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Abstract

A method (100) and device (90) for coding a digital image using intra-mode block prediction, wherein a list of prediction modes for each combination of prediction modes of the neighboring (U, L) blocks is obtained. The modes assigned to each combination of prediction modes may be divided into two groups. The first group includes n(where n is smaller than the overall number of available modes) most probable prediction modes and the second group includes the remaining modes. The modes in the first group are ordered according to their probability. This order may be specified as a list of modes ordered from most probable to the least probable mode. The modes belonging to the second group may be ordered in some predetermined manner, which may be specified depending on the information already available to the decoder (60).

Description

Attorney Docket No. 944-001.078-4-1
SPATIAL PREDICTION BASED INTRA CODING
Field of the Invention
The present invention relates generally to image coding and, more particularly, to coding blocks of video frames.
Background of the Invention
A digital image, such as a video image, a TV image, a still image or an image generated by a video recorder or a computer, consists of pixels arranged in horizontal and vertical lines. The number of pixels in a single image is typically in the tens of thousands. Each pixel typically contains luminance and chrominance information. Without compression, the quantity of information to be conveyed from an image encoder to an image decoder is so enormous that it renders real-time image transmission impossible. To reduce the amount of information to be transmitted, a number of different compression methods, such as JPEG, MPEG and H.263 standards, have been developed. In a typical video encoder, the frame of the original video sequence is partitioned into rectangular regions or blocks, which are encoded in Intra-mode (I-mode) or Inter-mode (P-mode). The blocks are coded independently using some kind of transform coding, such as DCT coding. However, pure block-based coding only reduces the inter-pixel correlation within a particular block, without considering the inter-block correlation of pixels, and it still produces high bit-rates for transmission. Current digital image coding standards also exploit certain methods that reduce the correlation of pixel values between blocks.
In general, blocks encoded in P-mode are predicted from one of the previously coded and transmitted frames. The prediction information of a block is represented by a two-dimensional (2D) motion vector. For the blocks encoded in I-mode, the predicted block is formed using spatial prediction from already encoded neighboring blocks within the same frame. The prediction error, i.e., the difference between the block being encoded and the predicted block is represented as a set of weighted basis functions of some discrete transform. The transform is typically performed on an 8x8 or 4x4 block basis. The weights - transform coefficients - are subsequently quantized. Quantization Attorney Docket No. 944-001.078-4-1
introduces loss of information and, therefore, quantized coefficients have lower precision than the originals.
Quantized transform coefficients, together with motion vectors and some control information, form a complete coded sequence representation and are referred to as syntax elements. Prior to transmission from the encoder to the decoder, all syntax elements are entropy coded so as to further reduce the number of bits needed for their representation. In the decoder, the block in the current frame is obtained by first constructing its prediction in the same manner as in the encoder and by adding to the prediction the compressed prediction error. The compressed prediction error is found by weighting the transform basis functions using the quantized coefficients. The difference between the reconstructed frame and the original frame is called reconstruction error.
The compression ratio, i.e., the ratio of the number of bits used to represent the original and compressed sequences, both in case of I- and P- blocks, is controlled by adjusting the value of the quantization parameter that is used to quantize transform coefficients. The compression ratio also depends on the employed method of entropy coding.
An example of spatial prediction used in a Working Draft Number 2 (WD2) of the JVT coder is described as follows. In order to perform the spatial prediction, the JVT coder offers 9 modes for prediction of 4x4 blocks, including DC prediction (Mode 0) and 8 directional modes, labeled 1 through 7, as shown in Figure 1. The prediction process is illustrated in Figure 2. As shown in Figure 2, the pixels from a to p are to be encoded, and pixels A to Q from neighboring blocks that have already been encoded are used for prediction. If, for example, Mode 1 is selected, then pixels a, e, i and m are predicted by setting them equal to pixel A, and pixels b, f, j and n are predicted by setting them equal to pixel B, etc. Similarly, if Mode 2 is selected, pixels a, b, c and d are predicted by setting them equal to pixel I, and pixels e, f, g and h are predicted by setting them equal to pixel J, etc. Thus, Mode 1 is a predictor in the vertical direction; and Mode 2 is a predictor in the horizontal direction. These modes are described in document VCEG-N54, published by ITU - Telecommunication Standardization Sector of Video Coding Expert Group (VCEG) in September 2001 , and in document JVT-B 118r2, published by the Joint Video Team of ISOTEC MPEG and ITU-T VCEG in March, 2002. Attorney Docket No. 944-001.078-4-1
Mode 0: DC prediction
Generally all samples are predicted by (A+B+C+D+I+J+K+L+4)»3. If four of the samples are outside the picture, the average of the remaining four is used for prediction. If all eight samples are outside the picture the prediction for all samples in the block is 128. A block may therefore always be predicted in this mode
Mode 1 : Vertical Prediction
If A, B, C, D are inside the picture, then - a, e. i, m are predicted by A,
- b, f, j, n are predicted by B, c, g. k, o are predicted by C,
- d, h. 1, p are predicted by D.
Mode 2: Horizontal Prediction
If E, F, G, H are inside the picture, then a, b, c, d are predicted by E,
- e, f, g, h are predicted by F, i, j, k, 1 are predicted by G, - m, n, o, p are predicted by H.
Mode 3: Diagonal Down/Right prediction
This mode is used only if all A, B, C, D, I, J, K, L, Q are inside the picture. This is a "diagonal" prediction. - m is predicted by (J + 2K + L + 2)»2
- i, n are predicted by (I + 2J + K + 2)»2
- e, j , o are predicted by (Q + 21 + J + 2)»2
- a, f, k, p are predicted by (A + 2Q + 1 + 2)»2
- b, g, 1 are predicted by (Q + 2A + B + 2)»2 - c, h are predicted by (A + 2B + C + 2)»2
- d is predicted by (B + 2C + D + 2)»2 Attorney Docket No. 944-001.078-4-1
Mode 4: Diagonal Down/Left prediction
This mode is used only if all A, B, C, D, I, J, K, L, Q are inside the picture. This is a "diagonal" prediction.
- a is predicted by (A + 2B + C + I + 2J + K + 4)»3 - b, e are predicted by (B + 2C + D + J + 2K + L + 4)»3
- c, f, i are predicted by (C + 2D + E + K + 2L + M + 4)»3
- d, g, j, m are predicted by (D + 2E + F + L + 2M + N + 4)»3
- h, k, n are predicted (E + 2F + G + M + 2N + O + 4)»3
- 1, o are predicted by (F + 2G + H + N + 2O + P + 4)»3 - p is predicted by (G + H + O + P + 2)»3
Mode 5: Vertical-Left prediction
This mode is used only if all A, B, C, D, I, J, K, L, Q are inside the picture. This is a "diagonal" prediction. - a, j are predicted by (Q + A + 1)»1
- b, k are predicted by (A + B + 1)»1
- c, 1 are predicted by (B + C + 1)»1
- d is predicted by (C + D + 1)»1
- e, n are predicted by (I + 2Q + A + 2)»2 - f, o are predicted by (Q + 2A + B + 2)»2
- g, p are predicted by (A + 2B + C + 2)»2
- h is predicted by (B + 2C + D + 2)»2
- i is predicted by (Q + 21 + J + 2)»2
- m is predicted by (1 + 2J + K + 2)»2
Mode 6: Vertical-Right prediction
This mode is used only if all A, B, C, D, I, J, K, L, Q are inside the picture. This is a "diagonal" prediction.
- a is predicted by (2A + 2B + J + 2K + L + 4)»3 - b, i are predicted by (B + C + 1)»1
- c, j are predicted by (C + D + 1)»1
- d, k are predicted by (D + E + 1 )»1 Attorney Docket No. 944-001.078-4-1
1 is predicted by (E + F + l)»l e is predicted by (A + 2B + C + K + 2L + M + 4)»3 f, m are predicted by (B + 2C + D + 2)»2 g, n are predicted by (C + 2D + E + 2)»2 h, o are predicted by (D + 2E + F + 2)»2 p is predicted by (E + 2F + G + 2)»2
Mode 7: Horizontal-Up prediction
This mode is used only if all A, B, C, D, I, J, K, L, Q are inside the picture. This is a "diagonal" prediction. a is predicted by (B + 2C + D + 21 + 2J + 4)»3 b is predicted by (C + 2D + E + 1 + 2 J + K + 4)»3 c, e are predicted by (D + 2E F + 2J + 2K + 4)»3 d, f are predicted by (E + 2F + G + J + 2K + L + 4)»3 g, i are predicted by (F + 2G + H + 2K + 2L + 4)»3 h, j are predicted by (G + 3H + K + 3L + 4)»3 1, n are predicted by (L + 2M + N + 2)»3 k, m are predicted by (G + H + L + M + 2)»2 o is predicted by (M + N + l)»l p is predicted by (M + 2N + O + 2)»2
Mode 8: Horizontal-Down prediction
This mode is used only if all A, B, C, D, I, J, K, L, Q are inside the picture. This is a "diagonal" prediction. a, g are predicted by (Q + I + 1)»1 b, h are predicted by (I + 2Q + A + 2)»2 c is predicted by (Q + 2A + B + 2)»2 d is predicted by (A + 2B + C + 2)»2 e, k are predicted by (I + J + l)»l f, 1 are predicted by (Q + 21 + J + 2)»2 i, o are predicted by (J + K + l)»l j, p are predicted by (I + 2J + K + 2)»2 Attorney Docket No. 944-001.078-4-1
m is predicted by (K + L + l)»l n is predicted by (J + 2K + L + 2)»2
Since each block must have a prediction mode assigned and transmitted to the decoder, this would require a considerable number of bits if coded directly. In order to reduce the amount of information to be transmitted, the correlation of the prediction modes of adjacent blocks can be used. For example, Vahteri et al. (WO 01/54416 Al, "A Method for Encoding Images and An Image Coder", hereafter referred to as Vahteri) discloses a block-based coding method wherein directionality information of the image within the blocks are used to classify a plurality of spatial prediction modes. The spatial prediction mode of a block is determined by the directionality information of at least one neighboring block.
In JVT coder, when the prediction modes of neighboring, already-coded blocks U and L are known, an ordering of the most probable prediction mode, the next most probable prediction mode, etc., for block C is given (Figure 3). The ordering of modes is specified for each combination of prediction modes of U and L. This order can be specified as a list of prediction modes for block C ordered from the most to the least probable one. The ordered list used in the WD2 of the JVT coder, as disclosed in VCEG- N54, is given below:
L/U outside 0 1 2 outside 0 01 10
0 02- 021648573 125630487 021876543 021358647 1 102654387 162530487 120657483 102536487 2 20- 280174365 217683504 287106435 281035764 3 201385476 125368470 208137546 325814670 4 201467835 162045873 204178635 420615837 5 015263847 152638407 201584673 531286407 6 016247583 160245738 206147853 160245837 7 270148635 217608543 278105463 270154863 8 280173456 127834560 287104365 283510764
L/U 4 outside -
0 206147583 512368047 162054378 204761853 208134657
1 162045378 156320487 165423078 612047583 120685734
2 287640153 215368740 216748530 278016435 287103654
3 421068357 531268470 216584307 240831765 832510476
4 426015783 162458037 641205783 427061853 204851763 Attorney Docket No. 944-001.078-4-1
5 125063478 513620847 165230487 210856743 210853647
6 640127538 165204378 614027538 264170583 216084573
7 274601853 271650834 274615083 274086153 278406153
8 287461350 251368407 216847350 287410365 283074165
TABLE I: Prediction mode as a function of ordering signalled in the bitstream
Here, an example of the prediction modes for the block C, as specified in the WD2 of the JVT coder, is given when the prediction mode for both U and L is 2. The string (2, 8, 7, 1, 0, 6, 4, 3, 5) indicates that mode 2 is also the most probable mode for block C. Mode 8 is the next most probable mode, etc. To the decoder the information will be transmitted indicating that the nth most probable mode will be used for block C. The ordering of the modes for block C can also be specified by listing the rank for each mode: the higher the rank, the less probable the prediction method. For the above example, the rank list would be (5, 4, 1, 8, 7, 9, 6, 3, 2). When the modes (0, 1, 2, 3, 4, 5, 6, 7, 8) are related to the rank list (5, 4, 1, 8, 7, 9, 6, 3, 2), we can tell that Mode 0 has a rank 5, Mode 1 has a rank 4, etc.
For more efficient coding, information on intra prediction of two 4x4 blocks can be coded in one codeword. The above-mentioned method has one major drawback - the memory required to keep ordering of prediction modes for block C given prediction modes of blocks U and L is demanding. In WD2 of the JVT coder, because 9 modes are used for prediction, there are 9x9 possible combinations of modes for blocks U and L. For each combination, an ordering of 9 possible modes has to be specified. That means that 9x9x9 bytes (here it is assumed that one number requires one byte) are needed to specify the ordering of prediction modes. In addition, more memory may be required to specify the special cases - for example, if one or both blocks U and L are not available.
Thus, it is advantageous and desirable to provide a method and device for coding a digital image wherein the memory requirements are reduced while the loss in coding efficiency is minimal. Attorney Docket No. 944-001.078-4-1
Summary of the Invention
A method and device for coding a digital image using intra-mode block prediction is provided. A list of prediction modes for each combination of prediction modes of the neighboring blocks is obtained. The modes assigned to each combination of prediction modes may be divided into two groups. The first group includes m (where m is smaller than the overall number n of available modes) most probable prediction modes and the second group includes the remaining modes. The modes in the first group are ordered according to their probability. This order may be specified as a list of modes ordered from most probable to the least probable mode. The modes belonging to the second group may be ordered in some predetermined manner, which may be specified depending on the information already available to the decoder. Information is sent to the decoder regarding whether the mode selected for a given block belongs to the first group or to the second group. If it belongs to the first group, the information is transmitted indicating that rth most probable mode shall be used for a block C given the combination of modes for blocks U and L. If the mode belongs to the second group, the information is transmitted indicating thaty'th mode of this group should be used.
The present invention will become apparent upon reading the description taken in conjunction with Figures 4a to 8.
Brief Description of the Drawings
Figure 1 is a schematic representation illustrating 8 directional modes that are used as spatial prediction modes.
Figure 2 is a schematic representation illustrating the pixels that are used for the prediction of a current 4x4 block of pixels. Figure 3 is a schematic representation illustrating two neighboring blocks being used for the prediction of a current block.
Figure 4a is a schematic representation illustrating the spatial prediction mode of two neighboring blocks used for the prediction of a current block.
Figure 4b is a schematic representation illustrating the spatial prediction mode of two neighboring blocks having a mirrored relationship with those of Figure 4a.
Figure 5a is a schematic representation illustrating another spatial prediction mode pair. Attorney Docket No. 944-001.078-4-1
Figure 5b is a schematic representation illustrating the mirrored mode pair.
Figure 6 is a flow-charting illustrating the method of spatial prediction.
Figure 7 is a block diagram illustrating a digital image block transfer system for implementing the method according to an embodiment of the present invention. Figure 8 is a block diagram illustrating a portable video telecommunications device implementing the method according to an embodiment of the present invention.
Best Mode for Carrying Out the Invention
An embodiment of the present invention utilizes the property that it is possible to obtain an ordered list of prediction modes for one combination of prediction modes of neighboring blocks as a function of prediction modes for another combination. For illustration purposes, prediction modes of two neighboring blocks U and L, as shown in Figure 3, are used to infer the prediction of the current block C. It is noted that a combination of prediction modes in Figure 4a can be obtained by flipping diagonally the prediction modes, as shown in Figure 4b. Accordingly, the nth most probable prediction mode for block C, when the combination of modes in Figure 4a is used, should be the same as the "flipped diagonally", ntb-most-probable prediction mode for the combination of modes in Figure 4b. Thus, if the neighboring blocks U and L have the modes "vertical" and "vertical", the prediction mode of the current block C is most probably "vertical" (Figure 4b). Consequently, when these blocks are "flipped" or mirrored against the diagonal ("down/right"), we know that from "horizontal" and "horizontal" we should get "horizontal" for the current block (Figure 4a). Similarly, if the neighboring blocks U and L are of Modes 2 and 3, as shown in Figure 5a, then the flipped blocks U and L will be of Modes 3 and 1, as shown in Figure 5b. To further illustrate this example, let us define the function/which maps the prediction direction i into j,j=f(i) as follows. Each prediction mode i is assigned a prediction mode j obtained by mirroring it about the diagonal line going from upper left corner of the block to lower right corner of the block. For the prediction modes in Figure 1 , the resulting assignment is summarized in Table II.
Figure imgf000011_0001
Attorney Docket No. 944-001.078-4-1
Figure imgf000012_0001
TABLE II
When the function is defined as above, the ordered list of prediction modes for the combination of modes (k, I) can be determined based on the ordered list for combination (i,j) such that i=f(l) and j=f(k), i.e., if the prediction mode/? is the nth most probable mode for the combination (i,j), the nth mode for the combination (k, I) is equal to ffp). As an example let us consider the combination of modes (1,1) to which the ordered list of modes for block C is assigned: (1, 6, 2, 5, 3, 0, 4, 8, 7). It should be possible to obtain the ordered list of the prediction modes for combination (2,2) from this ordered list by mapping using the function f: (2, 7, 1, 8, 3, 0, 4, 6, 5). Similarly, the ordered list of the prediction modes for combination (2,3) is (2, 0, 8, 1, 3, 7, 5, 4, 6) and the ordered list of modes/2,3)=(3,l) is/2, 0, 8, 1, 3, 7, 5, 4, 6) = (1, 0, 5, 2, 3, 6, 8, 4, 7). It should be noted that the ordered list of prediction modes for {k,l) can be substantially symmetrical to that for {ij). Thus, the mapping function/can be described as a mirroring function. The primary objective of the present invention is to reduce the size of the table specifying prediction mode as a function of prediction modes of already coded, neighboring blocks (e.g., TABLE I). This table is obtained during the training process. To find the ordered list of prediction modes for combination of modes (i,j) for some large number of blocks C for which neighboring blocks have this combination, the number each prediction mode is chosen according to a given selection criterion (e.g., the smallest prediction error) is counted. This number determines the rank of prediction mode in the list of prediction modes assigned to combination (ij), more frequently the mode is chosen, higher the rank it has in the list of prediction modes. When, during the training process the described mapping of the prediction modes is used, the resulting table specifying prediction modes will be smaller. If the ordered list for combination (k,l) can be obtained from ordered list for combination (ij) only the Attorney Docket No. 944-001.078-4-1
ordered list for combination (ij) has to be stored. During the training, the mapping can be introduced as follows. The frequency of occurrence of each prediction mode for the combinations (k, I) and (i,j) such that i=f(l) and j=f(k) is counted jointly, i.e., if prediction mode ? was chosen for combination (k,l) it is also counted that prediction mode f(p) was chosen for combination (ij). As well when prediction mode s was chosen for combination (ij) it is counted that prediction mode/Cs was chosen for combination {k,l).
The reduced prediction table, according to the present invention, is shown in TABLE III.
L/U outside 0 1 2 outside 0 01 10
0 02 024167835 150642387 027486135 013245867
1 150643278 021468735 105436287
2 20 124086573 283407156
3 385240167
4
5
6
7
8
L/U outside
0 012465738 150346287 160452387 024716835 028413765
1 104562378 156403287 165403278 014652738 014256837
2 240781635 214835076 241086735 207483165 280473156
3 413205876 531480267 146530287 247308516 832045176
4 420671835 145602387 461027538 407261835 248073165
5 513406287 165402387 240158376 082354167
6 614503287 614057328 042617385 024681357
7 427016385 426701835 284703615
8 328514067 248361075 248703651
TABLE III: Reduced Prediction Table
In TABLE III for some combinations (U, L), the ordered list of prediction modes is not given. The ordered lists for those combinations can be "restored" by mapping the corresponding elements that are retained in the prediction table when those "restored" elements are needed for the prediction of a current block. Thus, in general, as long as an element in the prediction table can be obtained or restored from another element in the Attorney Docket No. 944-001.078-4-1
prediction table by way of mapping, the former can be eliminated. In other words, in a prediction table comprising a first group of elements and a second group of elements, wherein each of the second group of elements can be restored from a corresponding element in the first group by a mapping function, the second group of elements can be eliminated.
Figure 6 is a flowchart illustrating the decoding stage when the symmetry in the prediction table is utilized. As shown, the method 100 comprises receiving a plurality of image blocks at step 110. When a current block is processed, it is determined at step 120 whether the prediction mode for the current block can be obtained from the prediction mode for the neighboring blocks without mapping. If so, then the spatial prediction mode of the current block is determined based on the prediction mode of the neighboring blocks at step 132. Otherwise, a complementary prediction mode of the neighboring blocks is provided at step 130, and a complementary prediction mode of the current block is determined based on the complementary prediction mode of the neighboring blocks at step 140. At step 150, the complementary prediction mode of the current block is mapped into the prediction mode of the current block.
Alternatively, it is possible to assign the same label to different prediction modes (grouping them together) of blocks U and L before using them to specify the prediction mode for block C. For example, in the case of the JVT coder, modes 1, 5 and 6 can be grouped together and labeled as 1, and modes 2, 7 and 8 can be grouped together and labeled as 2. As can be seen from Figure 1, the directions of modes 7 and 8 are close to the direction of mode 2, and the directions of modes 5 and 6 are close to the direction of mode 1. After this grouping, each of blocks U and L can have one of the 5 modes labeled as 0, 1, 2, 3 and 4. Therefore, instead of 9x9 possible combinations of prediction modes of U and L, there are only 5x5 such combinations. Accordingly, the memory required to specify ordering of prediction modes for block C, given prediction modes of blocks U and L, will be 5x5x9 bytes, instead of 9x9x9 bytes (assuming that 1 byte of memory is required to hold 1 number). Furthermore, if the mapping function/is used for "flipping" the ordered lists, the prediction table can be further simplified. An example of the table specifying prediction mode as a function of ordering signaled in the bitstream when both of these methods are used in conjunction is given in TABLE IV. Attorney Docket No. 944-001.078-4-1
L/U outside 0 1 2 3 4
Outside 0 01 10
0 02 024167835 150642387 024781635 013245867 012465738
1 156043278 021468375 153046827 140652378
2 20 214806357 283407156 247081635
3 385240167 413205876
4 420671835
TABLE IV
Moreover, it is also possible to limit the number of prediction modes for block C given prediction modes of blocks U and L. In the case of the JVT coder, there would still be 9x9 possible combination of prediction modes of U and L. But to each of these combinations only m modes would be assigned, where m is smaller than 9. Accordingly, the number of the probable prediction modes is reduced to (9x9xm)<(9x9x9). Similarly, if the mapping function/is used for "flipping" the ordered lists, the prediction table can be further simplified.
These methods can be used jointly or separately.
The spatial, prediction-based intra-coding, according to present invention, can be readily incorporated into a digital, image-block transfer system, as shown in Figure 7. Assuming that a frame is to be encoded in intra format using some form of intra prediction, encoding of the frame proceeds as follows. The blocks of the frame to be coded are directed one by one to the encoder 50 of the video transfer system presented in Figure 7. The blocks of the frame are received from a digital image source, e.g. a camera or a video recorder (not shown) at an input 27 of the image transfer system. In a manner known as such, the blocks received from the digital image source comprise image pixel values. The frame can be stored temporarily in a frame memory (not shown), or alternatively, the encoder receives the input data directly block by block.
The blocks are directed one by one to a prediction method selection block 35 that determines whether the pixel values of the current block to be encoded can be predicted on the basis of previously intra-coded blocks within the same frame or segment. In order to do this, the prediction method selection block 35 receives input from a frame buffer of the encoder 33, which contains a record of previously encoded and subsequently decoded Attorney Docket No. 944-001.078-4-1
and reconstructed intra blocks. In this way, the prediction method selection block can determine whether prediction of the current block can be performed on the basis of previously decoded and reconstructed blocks. Furthermore, if appropriate decoded blocks are available, the prediction method selection block 35 can select the most appropriate method for predicting the pixel values of the current block, if more than one such method may be chosen. It should be appreciated that in certain cases, prediction of the current block is not possible because appropriate blocks for use in prediction are not available in the frame buffer 33. In the situation where more than one prediction method is available, information about the chosen prediction method is supplied to multiplexer 13 for further transmission to the decoder. It should also be noted that in some prediction methods, certain parameters necessary to perform the prediction are transmitted to the decoder. This is, of course, dependent on the exact implementation adopted and in no way limits the application of the prediction-based intra coding according to the present invention. Pixel values of the current block are predicted in the intra prediction block 34. The intra prediction block 34 receives input concerning the chosen prediction method from the prediction method selection block 35 and information concerning the blocks available for use in prediction from frame buffer 33. On the basis of this information, the intra prediction block 34 constructs a prediction for the current block. The predicted pixel values for the current block are sent to a differential summer 28 which produces a prediction error block by taking the difference between the pixel values of the predicted current block and the actual pixel values of the current block received from input 27. Next, the error information for the predicted block is encoded in the prediction error coding block in an efficient form for transmission, for example using a discrete cosine transform (DCT). The encoded prediction error block is sent to multiplexer 13 for further transmission to the decoder. The encoder of the digital image transmission system also includes decoding functionality. The encoded prediction error of the current block is decoded in prediction error decoding block 30 and is subsequently summed in summer 31 with the predicted pixel values for the current block. In this way, a decoded version of the current block is obtained. The decoded current block is then directed to the frame buffer 33.
Here, it is also assumed that the receiver receives the blocks that form a digital image frame one by one from a transmission channel. Attorney Docket No. 944-001.078-4-1
In the receiver, 60, a demultiplexer receives the demultiplexed coded prediction error blocks and prediction information transmitted from the encoder 50. Depending on the prediction method in question, the prediction information may include parameters used in the prediction process. It should be appreciated that in the case that only one intra prediction method is used, information concerning the prediction method used to code the blocks is unnecessary, although it may still be necessary to transmit parameters used in the prediction process. In Figure 7, dotted lines are used to represent the optional transmission and reception of prediction method information and/or prediction parameters. Assuming more than one intra prediction method may be used, information concerning the choice of prediction method for the current block being decoded is provided to intra prediction block 41. Intra prediction block 41 examines the contents of frame buffer 39 to determine if there exist previously decoded blocks to be used in the prediction of the pixel values of the current block. If such image blocks exist, intra prediction block 41 predicts the contents of the current block using the prediction method indicated by the received prediction method information and possible prediction-related parameters received from the encoder. Prediction error information associated with the current block is received by prediction error decoding block 36, which decodes the prediction error block using an appropriate method. For example, if the prediction error information was encoded using a discrete cosine transform, the prediction error decoding block performs an inverse DCT to retrieve the error information. The prediction error information is then summed with the prediction for the current image block in summer 37 and the output of the summer is applied to the frame buffer 39. Furthermore, as each block is decoded, it is directed to the output of the decoder 40, for example, to be displayed on some form of display means. Alternatively, the image frame may be displayed only after the whole frame has been decoded and accumulated in the frame buffer 39.
It should be noted that the intra-prediction block 34 constructs a prediction of the current block based on the previously encoded and subsequently decoded and reconstructed intra blocks as provided by the frame buffer 33. In particular, the prediction of the current block is determined from the spatial prediction modes of the previously reconstructed intra blocks using a prediction table, as shown in TABLE III or TABLE IV (not shown in Figure 7). However, when the ordered list for the prediction Attorney Docket No. 944-001.078-4-1
modes {ij) of the previously reconstructed intra blocks are missing from the prediction table, a mapping block 32 can be used to map the spatial prediction modes of the previously reconstructed blocks into complementary or mirrored spatial prediction modes {k,l). At this point, the intra prediction block 34 can determine the complementary or mirrored prediction modefp) for the current block. Again the mapping block 32 is used to obtained the prediction mode/? of the current block by mapping the complementary prediction modefp). Likewise, a mapping block 38 is used for mapping when needed.
The mapping algorithm, which is used to perform the mapping of {ij) to {k,l) and the mapping offlp) to p, can be coded in a software program 69, which comprises machine executable steps or pseudo codes for performing the method according to the present invention. Advantageously, the software program is stored in a storage medium. For example, the software program is stored in a memory unit resident in a CPU 70, or in a separate memory unit 68, as shown in Figure 8. Figure 8 presents a simplified schematic diagram of a mobile terminal 90 intended for use as a portable video telecommunications device, incorporating the prediction mode mapping method of the present invention. The mobile terminal 90 comprises at least a display module 76 for displaying images, an image capturing device 72, and an audio module 74 for capturing audio information from an audio input device 82 and reproducing audio information on an audio producing device 80. Advantageously, the mobile terminal 90 further comprises a keyboard 78 for inputting data and commands, a radio frequency component 64 for communicating with a mobile telecommunications network and a signal/data processing unit 70 for controlling the operation of the telecommunications device. Preferably, the digital image block transfer system (50, 60) is implemented within in the processor 70. In accordance with a further embodiment of the present invention, memory requirements could be limited while achieving coding efficiency.
It has been observed that for each combination of modes for blocks U and L there are just a few modes for block C that have a high probability of occurrence. The probability of the remaining modes is much smaller. Moreover, probabilities of occurrence of these remaining modes are similar, and therefore, their order in the ordered set of modes does not have strong influence on the coding efficiency.
The modes assigned to each combination of prediction modes of U and L may be divided into two groups. The first group includes m (where m is smaller than the overall Attorney Docket No. 944-001.078-4-1
number n of available modes) most probable prediction modes and the second group includes the remaining modes. The modes in the first group are ordered according to their probability. As described above, this order may be specified as a list of modes ordered from most probable to the least probable mode. The modes belonging to the second group may be ordered in some predetermined manner, which may be specified depending on the information already available to the decoder. For example, prediction mode that is labeled using smaller number may precede prediction mode that is labeled using larger number.
In other words the prediction modes are arranged into an ordered set S. The ordered set of modes R assigned to combination of prediction modes for U and L is created by combining two ordered sets of modes
Figure imgf000019_0001
t2, .... tk} and V={v], v2, ..., vj:
R={tl, t2, .... tk, V], v2, .... ViJ.
The modes in the first ordered set T are ordered according to their expected probability of occurrence for combination of modes for neighboring blocks U and L. The more frequently the mode is expected to occur, the fewer bits should be used to signal it. The second ordered set of modes is created by removing elements of the first set from the set S and preserving the order of the remaining elements. For example, if prediction i preceded prediction mode / in the ordered set S, prediction i should precede prediction mode j in the set V.
As an exemplar, let us consider modes available in the JVT coder and assume that for each combination of modes for blocks U and L only the most probable mode is assigned to the first group. The remaining 8 modes are listed in the ascending order of their number. To further illustrate this exemplar, let us consider the combination of modes (1,1) to which mode 1 is assigned as the most probable mode. Mode 1 constitutes the first ordered set T. The second ordered set Fis created by removing mode 1 from the ordered set S, i.e., V= {0, 2, 3, 4, 5, 6, 7, 8}. Here the ordered set S is created by listing the nine prediction modes in ascending order of the numbers, i.e., S ={0, 1, 2, 3, 4, 5, 6, 7, 8}.
Information is sent to the decoder regarding whether the mode selected for a given block belongs to the first group or to the second group. If it belongs to the first group, the Attorney Docket No. 944-001.078-4-1
information is transmitted indicating that rth most probable mode shall be used for a block C given the combination of modes for blocks U and L. In our exemplar, if the decoder receives the information that first group is selected, no further information is required since only one mode belongs to this group. If the mode belongs to the second group, the information is transmitted indicating thaty'th mode of this group should be used. In our exemplar, if the information is received that the first mode should be selected, mode 0 should be chosen.
Implementation Alternatives: 1. The rules according to which the modes are ordered in set S may differ.
2. The way that the elements of the first set T are specified depends on the prediction modes of neighboring blocks U and L. The elements of this set can be specified for example as a table stored in the memory both of the encoder and decoder, or they can be inferred from the modes U and L themselves. 3. The signaling to the decoder of which mode is selected can be done in numerous ways, for example:
- The information about the rank of the prediction mode in the ordered set R can be transmitted.
- The information regarding which set or Fis selected is followed by the rank of the mode in the selected set.
Preferred implementation for the prediction modes specified in the JVT coder is described as follows.
The same label may be assigned to different prediction modes of blocks U and L before using them to specify prediction mode for block C. Diagonal modes 3, 5 and 8 are grouped together and labeled as 3, and diagonal modes 4, 6 and 7 are grouped together and labeled as 4. After this grouping, each of blocks U and L may have one of the 5 modes labeled as 0, 1, 2, 3 and 4. Therefore, instead of 9x9 possible combination of prediction modes of U and L there are only 5x5 such combinations. The ordered set S is created by listing the nine prediction modes in ascending order of their number, i.e., S = {0, 1, 2, 3, 4, 5, 6, 7, 8}. To each combination of prediction modes for U and L, only one most probable mode is assigned, i.e., the ordered Attorney Docket No. 944-001.078-4-1
set T for each combination consists of only one element. The assignment is given in Table V.
Figure imgf000021_0001
TABLE V
First information is sent to the decoder whether the most probable mode is used. This information is coded jointly for two 4x4 blocks as given in table below.
Figure imgf000021_0002
TABLE VI
X denotes that the most probable mode should be used. For the blocks for which the most probable mode m is not used, the code number from 0 to 7 is transmitted indicating which of the remaining modes should be used. Since the remaining modes are ordered according to their number, the mode with a smaller number precedes the mode with a higher number, when the code number q is received, the used prediction mode is equal to:
q, if q<m q+l, otherwise.
The code number q is sent as 3-bit codeword, which is the binary representation of the corresponding code number.
The savings in memory for the method, according to the present invention, comes from the fact that the decoder for each combination of modes of blocks U and L must store, at most, the ordered sets S and T, while S is identical for all the combination of modes for blocks U and L. Attorney Docket No. 944-001.078-4-1
In sum, the present invention provides methods, devices and systems for coding into a bitstream and decoding from the bitstream image information comprising a plurality of image blocks using a plurality of spatial prediction modes for intra-mode block prediction. The spatial prediction mode of a current block (C) can be determined based on a plurality of derived prediction modes, derived from the spatial prediction modes of a plurality of neighboring blocks (U, L) of the current block (C). The plurality of n derived prediction modes are grouped into a first group of m first prediction modes with m<n and a second group of second prediction modes. The first prediction modes have a higher probability of occurrence than the second prediction modes. While the first prediction modes are ordered according to their probability of occurrence, the second prediction modes are arranged in a predetermined fashion known to the decoder. Thus, an ordered set is provided to the decoding device so as to allow the decoding device to determine the order of the second prediction modes based on the provided ordered set. The ordered set is associated with one or more group of the spatial prediction modes of the neighboring blocks (U, L) of the current block (C). Furthermore, the bitstream may include coded information indicative of which of the first prediction modes has the highest probability of occurrence when the derived prediction mode with the highest probability of occurrence is selected for use in coding the current block (C). The present invention also provides a computer program having pseudo codes for use in grouping the plurality of derived prediction modes into the first and second groups, and in ordering the first prediction modes according to the probability of occurrence among the first prediction modes.
Although the invention has been described with respect to a preferred embodiment thereof, it will be understood by those skilled in the art that the foregoing and various other changes, omissions and deviations in the form and detail thereof may be made without departing from the scope of this invention.

Claims

Attorney Docket No. 944-001.078-4-1What is claimed is:
1. A method of coding into a bitstream image information comprising a plurality of image blocks using a plurality of spatial prediction modes for intra-mode block prediction, wherein the spatial prediction mode of a current block (C) is determined based on a plurality of derived prediction modes, which are derived based on the spatial prediction modes of a plurality of neighboring blocks (U, L) of the current block (C), said method characterized by grouping said plurality of derived prediction modes into a first group and a second group, the first group having a first number of first prediction modes and the second group having a second number of second prediction modes, wherein the first number is smaller than the number of the derived prediction modes, and wherein the first prediction modes have a higher probability of occurrence than the second prediction modes, and coding into the bitstream information indicative of whether the spatial prediction mode of the current block (C) belongs to the first group or the second group.
2. The method of claim 1 , further characterized by ordering the first prediction modes according to the probability of occurrence among the first prediction modes.
3. The method of claim 1, further characterized by arranging the second prediction modes in a predetermined fashion known to the decoding device.
4. The method of claim 1, further characterized by coding into the bitstream information indicative of which of the first prediction modes has a highest probability of occurrence when the derived prediction mode with the highest probability of occurrence is selected for use in coding the current block (C).
5. The method of claim 1, further characterized in that an ordered set of prediction modes is known to the decoding device so that the decoding device determines the order of the second prediction modes based on the ordered set. Attorney Docket No. 944-001.078-4-1
6. The method of claim 5, further characterized in that the ordered set is associated with more than one group of the spatial prediction modes of a plurality of neighboring blocks (U, L) of the current block (C).
7. The method of claim 1 , further characterized in that the derived prediction modes are representable by a plurality of different integers and the second prediction modes are ordered according to an order of the integers known to the decoding device.
8. The method of claim 1 , wherein the derived prediction modes are representable by a plurality of different integers, each integer corresponding to a derived prediction mode, and wherein the integers are arranged in an ascending order of the integers for providing an ordered set, said method further characterized by removing the integers corresponding to the first prediction modes from the ordered set for providing a modified ordered set, so as to allow the decoding device to determine the order of the second group based on the modified ordered set.
9. The method of claim 1 , wherein one of said plurality of derived prediction modes is selected for use in coding the current block (C), said method further characterized by providing the decoding device with information indicative of an ,'th mode among the second prediction modes if the selected one of the combined prediction modes is in the second group.
10. The method of claim 1 , further characterized by mapping the spatial prediction modes of the neighboring blocks for providing a complementary prediction mode of the neighboring blocks when needed, by determining a complementary prediction mode of the current block (C) based on the complementary prediction mode of the neighboring blocks, and by mapping the complementary prediction mode of the current block (C) for obtaining on the spatial prediction mode of the current block (C). Attorney Docket No. 944-001.078-4-1
11. The method of claim 10, characterized in that the mapping of the complementary prediction mode of the block (C) is carried out by a mirroring function mirroring the first and second blocks.
12. An encoding device for coding an image comprising a plurality of image blocks using a plurality of spatial prediction modes for intra-mode block prediction, wherein the spatial prediction mode of a current block (C) is determined based on a plurality of derived prediction modes, which are derived based on the spatial prediction modes of a plurality of neighboring blocks (U, L) of the current block (C), said encoding device characterized by means, for grouping said plurality of derived prediction modes into a first group and a second group, the first group having a first number of first prediction modes and the second group having a second number of second prediction modes, wherein the first number is smaller than the number of the derived prediction modes, and wherein the first prediction modes have a higher probability of occurrence than the second prediction modes, and the second prediction modes are ordered in a predetermined fashion known to the decoding device, and means, for coding into a bitstream information indicative of whether the spatial prediction mode of the current block (C) belongs to the first group or the second group.
13. The encoding device of claim 12, further characterized by means, responsive to the first group, for ordering the first prediction modes according to probability of occurrence among the first prediction modes for providing an ordered set.
14. The encoding device of claim 12, further characterized by means, for providing the decoding device information indicative of the prediction modes in the ordered set that has a highest probability of occurrence.
15. The encoding device of claim 12, further characterized by means capable of providing a complementary prediction mode of the neighboring blocks when needed based on the spatial prediction modes of the neighboring blocks so Attorney Docket No. 944-001.078-4-1
that a complementary prediction mode of the current block can be determined based on the complementary prediction mode of the neighboring blocks, and means, responsive to the complementary prediction mode of the current mode, for providing the spatial prediction mode of the current block (C) based on a mapping of the complementary prediction mode of the cuπent mode.
16. A method for decoding from a bitstream image information comprising a plurality of image blocks using a plurality of spatial prediction modes for intra-mode block prediction, wherein the spatial prediction mode of a current block (C) is determined based on a plurality of derived prediction modes, which are derived based on the spatial prediction modes of a plurality of neighboring blocks (U, L) of the current block (C), said method characterized in that said plurality of derived prediction modes are grouped into a first group and a second group, the first group having a first number of first prediction modes and the second group having a second number of second prediction modes, wherein the first number is smaller than the number of the derived prediction modes, and wherein the first prediction modes have a higher probability of occurrence than the second prediction modes, said method characterized by decoding from the bitstream information indicative of whether the spatial prediction mode of the current block (C) belongs to the first group or the second group so as to allow the decoding device to determine the spatial prediction mode of the current block (C) based on the decoded information.
17. The method of claim 16, further characterized in that the first prediction modes are ordered according to the probability of occurrence among the first prediction modes.
18. The method of claim 16, further characterized in that the second prediction modes are aπanged in a predetermined fashion known to the decoding device.
19. The method of claim 16, further characterized in that the decoded information is also indicative of which of the first prediction modes has a highest probability of Attorney Docket No. 944-001.078-4-1
occurrence when the combined prediction mode with the highest probability of occurrence is selected for use in coding and decoding the current block (C).
20. The method of claim 16, further characterized in that an ordered set is provided to the decoding device so as to allow the decoding device to determine the order of the second prediction modes based on the ordered set.
21. A decoder capable of decoding from a bitstream image information comprising a plurality of image blocks using a plurality of spatial prediction modes for intra-mode block prediction, wherein the spatial prediction mode of a current block (C) is determined based on a plurality of derived prediction modes, which are derived based on the spatial prediction modes of a plurality of neighboring blocks (U, L) of the current block (C), characterized in that said plurality of derived prediction modes are grouped into a first group and a second group, the first group having a first number of first prediction modes and the second group having a second number of second prediction modes, wherein the first number is smaller than the number of the derived prediction modes, and wherein the first prediction modes have a higher probability of occurrence than the second prediction modes, said decoder characterized by means, responsive to decoded information, for determining whether the spatial prediction mode of the current block (C) belongs to the first group or the second group, and means for selecting the spatial prediction mode based on said determining.
22. The decoder of claim 21 , characterized in that the first prediction modes are ordered according to the probability of occurrence among the first prediction modes.
23. The decoder of claim 21 , characterized in that the second prediction modes are arranged in a predetermined fashion, said decoder further characterized by means for storing information indicative to said predetermined fashion. Attorney Docket No. 944-001.078-4-1
24. The decoder of claim 21 , said determining means is also capable of determining based on the decoded information which of the first prediction modes has a highest probability of occurrence when the derived prediction mode with the highest occurrence mode is selected for use in decoding the current block (C).
25. An image coding system for coding and decoding an image comprising a plurality of image blocks using a plurality of spatial prediction modes for intra-mode block prediction, wherein the spatial prediction mode of a current block (C) is determined based on a plurality of derived prediction modes, which are derived based on the prediction modes of a plurality of neighboring blocks (U, L) of the current block (C), said coding system characterized by means, for grouping said plurality of derived prediction modes into a first group and a second group, the first group having a first number of first prediction modes and the second group having a second number of second prediction modes, wherein the first number is smaller than the number of the derived prediction modes, and the first prediction modes have a higher probability of occurrence than the second prediction modes, means, for coding into a bitstream group information indicative of whether the spatial prediction mode of the current block (C) belongs to the first group or the second group, and means, for decoding from the bitstream said group information so as to allow the decoding device to determine the spatial prediction mode of the current block (C) based on said decoded information.
26. The image coding system of claim 25, further characterized by means, responsive to the first group, for ordering the first prediction modes according to probability of occurrence among the first prediction modes.
27. The image coding system of claim 25, further characterized by means, responsive to the second group, for arranging the second prediction modes in a predetermined fashion known to the decoding device. Attorney Docket No. 944-001.078-4-1
28. A computer program for use in an image coding system for coding into a bitstream image information comprising a plurality of image blocks using a plurality of spatial prediction modes for intra-mode block prediction, wherein the spatial prediction mode of a block (C) is determined based on a plurality of derived prediction modes, which are derived based on the prediction modes of a plurality of neighboring blocks (U, L) of the block (C), said computer program characterized by a pseudo code for use in grouping said plurality of derived prediction modes into a first group and a second group, the first group having a first number of first prediction modes and the second group having a second number of second prediction modes, wherein the first number is smaller than the number of the derived prediction modes, and the first prediction modes have a higher probability of occurrence than the second prediction modes, and a pseudo code for use in ordering the first prediction modes according to probability of occurrence among the first prediction modes.
29. The computer program of claim 28, further characterized by a pseudo code for use in arranging the second prediction modes in a predetermined fashion known to the decoding device.
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Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1653745A2 (en) * 2004-10-26 2006-05-03 Nec Corporation Image encoder and method thereof, computer program of image encoder, and mobile terminal
CN100348051C (en) * 2005-03-31 2007-11-07 华中科技大学 An enhanced in-frame predictive mode coding method
WO2009004985A1 (en) * 2007-06-29 2009-01-08 Sharp Kabushiki Kaisha Image encoding device, image encoding method, image decoding device, image decoding method, program, and recording medium
WO2010021664A1 (en) * 2008-08-20 2010-02-25 Thomson Licensing Depth coding
WO2010077071A2 (en) * 2009-01-05 2010-07-08 에스케이텔레콤 주식회사 Block mode encoding/decoding method and apparatus, and method and apparatus for image encoding/decoding using the same
WO2011152635A2 (en) * 2010-05-30 2011-12-08 Lg Electronics Inc. Enhanced intra prediction mode signaling
US8279920B2 (en) 2009-03-24 2012-10-02 Via Technologies, Inc. Intra-frame prediction method and prediction apparatus using the same
EP2608541A2 (en) * 2010-08-17 2013-06-26 Oh, Soo-mi Method for decoding intra-predictions
WO2013109066A1 (en) * 2012-01-20 2013-07-25 주식회사 팬택 Intra prediction mode mapping method and device using the method
TWI407797B (en) * 2009-03-27 2013-09-01 Via Tech Inc Intra-frame prediction method and prediction apparatus using the same
US8761254B2 (en) 2007-06-04 2014-06-24 Ntt Docomo, Inc. Image prediction encoding device, image prediction decoding device, image prediction encoding method, image prediction decoding method, image prediction encoding program, and image prediction decoding program
JP2014161094A (en) * 2004-06-27 2014-09-04 Apple Inc Selecting encoding types and predictive modes for encoding video data
US8913662B2 (en) 2011-01-06 2014-12-16 Qualcomm Incorporated Indicating intra-prediction mode selection for video coding using CABAC
US8913105B2 (en) 2009-01-07 2014-12-16 Thomson Licensing Joint depth estimation
US9025661B2 (en) 2010-10-01 2015-05-05 Qualcomm Incorporated Indicating intra-prediction mode selection for video coding
US9154796B2 (en) 2011-11-04 2015-10-06 Qualcomm Incorporated Intra-mode video coding
US9179153B2 (en) 2008-08-20 2015-11-03 Thomson Licensing Refined depth map
US9554154B2 (en) 2010-07-31 2017-01-24 M & K Holding Inc. Image encoding apparatus adaptively determining a scan pattern according to an intra prediction mode
US9716886B2 (en) 2010-08-17 2017-07-25 M&K Holdings Inc. Method for restoring an intra prediction mode
US9930332B2 (en) 2011-09-12 2018-03-27 Canon Kabushiki Kaisha Deriving reference mode values and encoding and decoding information representing prediction modes
US10198792B2 (en) 2009-10-14 2019-02-05 Dolby Laboratories Licensing Corporation Method and devices for depth map processing
US10264280B2 (en) 2011-06-09 2019-04-16 Qualcomm Incorporated Enhanced intra-prediction mode signaling for video coding using neighboring mode
US10652533B2 (en) 2011-09-28 2020-05-12 Electronics And Telecommunications Research Institute Method and apparatus for encoding/decoding intra prediction mode
US10951884B2 (en) 2017-01-16 2021-03-16 Industry Academy Cooperation Foundation Of Sejong University Method and apparatus for encoding/decoding an image signal
US11252407B2 (en) 2011-09-28 2022-02-15 Electronics And Telecommunications Research Institute Method and apparatus for encoding/decoding intra prediction mode
US11284072B2 (en) 2010-08-17 2022-03-22 M&K Holdings Inc. Apparatus for decoding an image
US11659169B2 (en) 2018-09-13 2023-05-23 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Affine Linear Weighted Intra Predictions
US11700384B2 (en) 2011-07-17 2023-07-11 Qualcomm Incorporated Signaling picture size in video coding

Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100716999B1 (en) 2005-06-03 2007-05-10 삼성전자주식회사 Method for intra prediction using the symmetry of video, method and apparatus for encoding and decoding video using the same
JP5089878B2 (en) * 2005-10-28 2012-12-05 パナソニック株式会社 Image encoding device
EP2090112A4 (en) * 2006-11-07 2014-04-23 Samsung Electronics Co Ltd Method and apparatus for encoding and decoding based on intra prediction
JP2010135864A (en) * 2007-03-29 2010-06-17 Toshiba Corp Image encoding method, device, image decoding method, and device
US8189676B2 (en) * 2007-04-05 2012-05-29 Hong Kong University Of Science & Technology Advance macro-block entropy coding for advanced video standards
JP5004180B2 (en) * 2007-11-07 2012-08-22 Kddi株式会社 Video encoding apparatus and decoding apparatus
JP5166339B2 (en) * 2008-03-28 2013-03-21 三星電子株式会社 Method and apparatus for encoding and / or decoding intra prediction mode information of image
JP2009272969A (en) * 2008-05-09 2009-11-19 Hitachi Ltd Image encoding apparatus and image encoding method, and image decoding apparatus and image decoding method
JP4995789B2 (en) * 2008-08-27 2012-08-08 日本電信電話株式会社 Intra-screen predictive encoding method, intra-screen predictive decoding method, these devices, their programs, and recording media recording the programs
CN102308586B (en) * 2009-02-06 2015-03-25 汤姆森特许公司 Methods and apparatus for implicit and semi-implicit intra mode signaling for video and decoders
JP5746182B2 (en) * 2009-09-14 2015-07-08 トムソン ライセンシングThomson Licensing Efficient video encoding and decoding method and apparatus for intra prediction mode
KR101441879B1 (en) * 2009-12-09 2014-09-23 에스케이텔레콤 주식회사 Video encoding apparatus and method, transform encoding apparatus and method, basis transform generating apparatus and method, and video decoding apparatus and method
WO2011078562A2 (en) * 2009-12-21 2011-06-30 한국전자통신연구원 Intra-predictive coding and decoding methods, and intra-predictive coding and decoding devices for performing the methods
MY186093A (en) * 2010-07-15 2021-06-21 Velos Media Int Ltd Image encoding device, and image decoding device
JP5781313B2 (en) 2011-01-12 2015-09-16 株式会社Nttドコモ Image prediction coding method, image prediction coding device, image prediction coding program, image prediction decoding method, image prediction decoding device, and image prediction decoding program
CN102611885B (en) * 2011-01-20 2014-04-30 华为技术有限公司 Encoding and decoding method and device
WO2012113197A1 (en) * 2011-02-24 2012-08-30 中兴通讯股份有限公司 Encoding or decoding method of prediction mode, and device thereof
WO2013111977A1 (en) * 2012-01-26 2013-08-01 한국전자통신연구원 Deblocking method and deblocking apparatus for block on which intra prediction is performed
CN103369315B (en) * 2012-04-06 2016-08-24 华为技术有限公司 The coding of the intra prediction mode of chromatic component, coding/decoding method, equipment and system
WO2013155666A1 (en) * 2012-04-16 2013-10-24 Mediatek Singapore Pte. Ltd. Methods and apparatuses of intra mode coding for hevc
GB2509901A (en) * 2013-01-04 2014-07-23 Canon Kk Image coding methods based on suitability of base layer (BL) prediction data, and most probable prediction modes (MPMs)
JP5775959B2 (en) * 2014-11-07 2015-09-09 株式会社Nttドコモ Image prediction coding method, image prediction coding device, image prediction coding program, image prediction decoding method, image prediction decoding device, and image prediction decoding program
US20180048915A1 (en) * 2015-02-27 2018-02-15 Lg Electronics Inc. Method and apparatus for encoding/decoding a video signal
JP6038243B2 (en) * 2015-07-15 2016-12-07 株式会社Nttドコモ Image predictive decoding method and image predictive decoding device
JP6310992B2 (en) * 2016-11-01 2018-04-11 株式会社Nttドコモ Image predictive decoding method and image predictive decoding device
JP6486528B2 (en) * 2018-03-19 2019-03-20 株式会社Nttドコモ Image predictive decoding method and image predictive decoding device

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR940023248A (en) * 1993-03-15 1994-10-22 오오가 노리오 Image signal encoding method and apparatus, Image signal decoding method and apparatus
CN1134993C (en) * 1996-04-18 2004-01-14 诺基亚流动电话有限公司 Vedio data encoder and decoder
US5974184A (en) * 1997-03-07 1999-10-26 General Instrument Corporation Intra-macroblock DC and AC coefficient prediction for interlaced digital video
US6275533B1 (en) * 1997-06-20 2001-08-14 Matsushita Electric Industrial Co., Ltd. Image processing method, image processing apparatus, and data recording medium
FI116819B (en) * 2000-01-21 2006-02-28 Nokia Corp Procedure for transferring images and an image encoder
EP1347649A1 (en) * 2002-03-18 2003-09-24 Lg Electronics Inc. B picture mode determining method and apparatus in video coding system

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
"ITU-telecommunication standardization sector", VIDEO CODING EXPERT GROUP (VCEG), September 2001 (2001-09-01), pages 1 - 10, XP002969249 *
"Joint video team of ISO/IEC MPEG and ITU-T VCEG", DRAFT ISO/IEC 14496-10, February 2002 (2002-02-01), XP002969250 *
See also references of EP1512115A4 *

Cited By (100)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014161094A (en) * 2004-06-27 2014-09-04 Apple Inc Selecting encoding types and predictive modes for encoding video data
EP1653745A3 (en) * 2004-10-26 2012-04-04 NEC Corporation Image encoder and method thereof, computer program of image encoder, and mobile terminal
EP1653745A2 (en) * 2004-10-26 2006-05-03 Nec Corporation Image encoder and method thereof, computer program of image encoder, and mobile terminal
CN100348051C (en) * 2005-03-31 2007-11-07 华中科技大学 An enhanced in-frame predictive mode coding method
US8761254B2 (en) 2007-06-04 2014-06-24 Ntt Docomo, Inc. Image prediction encoding device, image prediction decoding device, image prediction encoding method, image prediction decoding method, image prediction encoding program, and image prediction decoding program
US9667976B2 (en) 2007-06-29 2017-05-30 Sharp Kabushiki Kaisha Image encoding device, image encoding method, image decoding device, image decoding method, program, and storage medium
US8644382B2 (en) 2007-06-29 2014-02-04 Sharp Kabushiki Kaisha Image encoding device, image encoding method, image decoding device, image decoding method, program, and storage medium
US9955171B2 (en) 2007-06-29 2018-04-24 Velos Media, Llc. Image decoder, image decoding method, image encoder, and image encode method
WO2009004985A1 (en) * 2007-06-29 2009-01-08 Sharp Kabushiki Kaisha Image encoding device, image encoding method, image decoding device, image decoding method, program, and recording medium
US11109037B2 (en) 2007-06-29 2021-08-31 Velos Media, Llc Image decoder, image decoding method, image encoder, and image encode method
US10306237B2 (en) 2007-06-29 2019-05-28 Velos Media, Llc Image decoder, image decoding method, image encoder, and image encode method
US9161037B2 (en) 2007-06-29 2015-10-13 Sharp Kabushiki Kaisha Image encoding device, image encoding method, image decoding device, image decoding method, program, and storage medium
WO2010021664A1 (en) * 2008-08-20 2010-02-25 Thomson Licensing Depth coding
US9179153B2 (en) 2008-08-20 2015-11-03 Thomson Licensing Refined depth map
WO2010077071A3 (en) * 2009-01-05 2010-09-30 에스케이텔레콤 주식회사 Block mode encoding/decoding method and apparatus, and method and apparatus for image encoding/decoding using the same
US8811469B2 (en) 2009-01-05 2014-08-19 Sk Telecom Co., Ltd. Block mode encoding/decoding method and apparatus, and method and apparatus for image encoding/decoding using the same
WO2010077071A2 (en) * 2009-01-05 2010-07-08 에스케이텔레콤 주식회사 Block mode encoding/decoding method and apparatus, and method and apparatus for image encoding/decoding using the same
US8913105B2 (en) 2009-01-07 2014-12-16 Thomson Licensing Joint depth estimation
US8279920B2 (en) 2009-03-24 2012-10-02 Via Technologies, Inc. Intra-frame prediction method and prediction apparatus using the same
TWI407797B (en) * 2009-03-27 2013-09-01 Via Tech Inc Intra-frame prediction method and prediction apparatus using the same
US10198792B2 (en) 2009-10-14 2019-02-05 Dolby Laboratories Licensing Corporation Method and devices for depth map processing
US10417748B2 (en) 2009-10-14 2019-09-17 Dolby Laboratories Licensing Corporation Filtering and edge encoding and decoding for depth maps
US11800117B2 (en) 2010-05-30 2023-10-24 Lg Electronics Inc. Enhanced intra prediction mode signaling
CN105141950A (en) * 2010-05-30 2015-12-09 Lg电子株式会社 Enhanced intra mode signaling
WO2011152635A2 (en) * 2010-05-30 2011-12-08 Lg Electronics Inc. Enhanced intra prediction mode signaling
US8902978B2 (en) 2010-05-30 2014-12-02 Lg Electronics Inc. Enhanced intra prediction mode signaling
US11297331B2 (en) 2010-05-30 2022-04-05 Lg Electronics Inc. Enhanced intra prediction mode signaling
CN105141950B (en) * 2010-05-30 2018-04-13 Lg电子株式会社 The intra prediction mode signaling of enhancing
CN102918844B (en) * 2010-05-30 2015-11-25 Lg电子株式会社 The intra prediction mode signaling strengthened
CN105141949A (en) * 2010-05-30 2015-12-09 Lg电子株式会社 Enhanced intra mode signaling
CN105141951A (en) * 2010-05-30 2015-12-09 Lg电子株式会社 Enhanced intra mode signaling
EP2391130A3 (en) * 2010-05-30 2012-02-15 LG Electronics Inc. Enhanced intra mode signaling
CN105227951A (en) * 2010-05-30 2016-01-06 Lg电子株式会社 The intra prediction mode signaling strengthened
US9398303B2 (en) 2010-05-30 2016-07-19 Lg Electronics Inc. Enhanced intra prediction mode signaling
US10390023B2 (en) 2010-05-30 2019-08-20 Lg Electronics Inc. Enhanced intra prediction mode signaling
CN102918844A (en) * 2010-05-30 2013-02-06 Lg电子株式会社 Enhanced intra prediction mode signaling
CN105141949B (en) * 2010-05-30 2019-04-19 Lg电子株式会社 Method and apparatus for handling vision signal
US10742997B2 (en) 2010-05-30 2020-08-11 Lg Electronics Inc. Enhanced intra prediction mode signaling
WO2011152635A3 (en) * 2010-05-30 2012-04-19 Lg Electronics Inc. Enhanced intra prediction mode signaling
US10034003B2 (en) 2010-05-30 2018-07-24 Lg Electronics Inc. Enhanced intra prediction mode signaling
CN105141951B (en) * 2010-05-30 2018-05-04 Lg电子株式会社 The intra prediction mode signaling of enhancing
US9554154B2 (en) 2010-07-31 2017-01-24 M & K Holding Inc. Image encoding apparatus adaptively determining a scan pattern according to an intra prediction mode
US9584829B2 (en) 2010-07-31 2017-02-28 M&K Holdings Inc. Image encoding apparatus adaptively determining a scan pattern according to an intra prediction mode
USRE48564E1 (en) 2010-07-31 2021-05-18 M&K Holdings Inc. Image decoding apparatus adaptively determining a scan pattern according to an intra prediction mode
US9609360B2 (en) 2010-07-31 2017-03-28 M&K Holdings Inc. Image decoding apparatus adaptively determining a scan pattern according to an intra prediction mode
US9609359B2 (en) 2010-07-31 2017-03-28 M&K Holdings Inc. Image decoding apparatus adaptively determining a scan pattern according to an intra prediction mode
US9584826B2 (en) 2010-07-31 2017-02-28 M&K Holdings Inc. Image encoding apparatus adaptively determining a scan pattern according to an intra prediction mode
US9584827B2 (en) 2010-07-31 2017-02-28 M&K Holdings Inc. Image encoding apparatus adaptively determining a scan pattern according to an intra prediction mode
US9578349B2 (en) 2010-07-31 2017-02-21 M&K Holdings Inc. Image decoding apparatus adaptively determining a scan pattern according to an intra prediction mode
US9584828B2 (en) 2010-07-31 2017-02-28 M&K Holdings Inc. Image encoding apparatus adaptively determining a scan pattern according to an intra prediction mode
US9584830B2 (en) 2010-07-31 2017-02-28 M&K Holdings Inc. Image decoding apparatus adaptively determining a scan pattern according to an intra prediction mode
CN104602004A (en) * 2010-08-17 2015-05-06 M&K控股株式会社 method for decoding intra predictions
EP3125554A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Apparatus for encoding an intra prediction mode
EP3125556A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Method for restoring an intra prediction mode
EP3125557A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Apparatus for encoding an intra prediction mode
EP3125558A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Method for restoring an intra prediction mode
EP3125552A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Method for restoring an intra prediction mode
US9716886B2 (en) 2010-08-17 2017-07-25 M&K Holdings Inc. Method for restoring an intra prediction mode
EP2608541A2 (en) * 2010-08-17 2013-06-26 Oh, Soo-mi Method for decoding intra-predictions
US9918086B2 (en) 2010-08-17 2018-03-13 M&K Holdings Inc. Method for encoding an intra prediction mode
US9918087B2 (en) 2010-08-17 2018-03-13 M&K Holdings Inc. Method for encoding an intra prediction mode
US9924187B2 (en) 2010-08-17 2018-03-20 M&K Holdings Inc. Method for restoring an intra prediction mode
US9924186B2 (en) 2010-08-17 2018-03-20 M&K Holdings Inc. Method for encoding an intra prediction mode
US11284072B2 (en) 2010-08-17 2022-03-22 M&K Holdings Inc. Apparatus for decoding an image
EP3125553A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Method for restoring an intra prediction mode
EP3125561A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Method for restoring an intra prediction mode
EP3125555A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Method for restoring an intra prediction mode
EP2608541A4 (en) * 2010-08-17 2014-05-14 Infobridge Pte Ltd Method for decoding intra-predictions
US10003795B2 (en) 2010-08-17 2018-06-19 M&K Holdings Inc. Method for encoding an intra prediction mode
EP3125560A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Apparatus for decoding an intra prediction mode
US10063854B2 (en) 2010-08-17 2018-08-28 M&K Holdings Inc. Apparatus for decoding an image
US10085019B2 (en) 2010-08-17 2018-09-25 M&K Holdings Inc. Method for restoring an intra prediction mode
US10123009B2 (en) 2010-08-17 2018-11-06 M&K Holdings Inc. Apparatus for encoding an image
US10123010B2 (en) 2010-08-17 2018-11-06 M&K Holding Inc. Apparatus for encoding an image
US10136130B2 (en) 2010-08-17 2018-11-20 M&K Holdings Inc. Apparatus for decoding an image
US10567760B2 (en) 2010-08-17 2020-02-18 M&K Holdings Inc. Apparatus for encoding an image
EP3125559A1 (en) * 2010-08-17 2017-02-01 M&K Holdings Inc. Apparatus for decoding an intra prediction mode
CN106231308B (en) * 2010-08-17 2019-04-12 M&K控股株式会社 Method for encoding intra prediction mode
US9491478B2 (en) 2010-08-17 2016-11-08 M&K Holdings Inc. Method for decoding in intra prediction mode
CN106231308A (en) * 2010-08-17 2016-12-14 M&K控股株式会社 Method for coded frame inner estimation mode
US9025661B2 (en) 2010-10-01 2015-05-05 Qualcomm Incorporated Indicating intra-prediction mode selection for video coding
US8913662B2 (en) 2011-01-06 2014-12-16 Qualcomm Incorporated Indicating intra-prediction mode selection for video coding using CABAC
US10264280B2 (en) 2011-06-09 2019-04-16 Qualcomm Incorporated Enhanced intra-prediction mode signaling for video coding using neighboring mode
US11700384B2 (en) 2011-07-17 2023-07-11 Qualcomm Incorporated Signaling picture size in video coding
US9930332B2 (en) 2011-09-12 2018-03-27 Canon Kabushiki Kaisha Deriving reference mode values and encoding and decoding information representing prediction modes
US11729380B2 (en) 2011-09-28 2023-08-15 Electronics And Telecommunications Research Institute Method and apparatus for encoding/decoding intra prediction mode
US10652533B2 (en) 2011-09-28 2020-05-12 Electronics And Telecommunications Research Institute Method and apparatus for encoding/decoding intra prediction mode
US11252407B2 (en) 2011-09-28 2022-02-15 Electronics And Telecommunications Research Institute Method and apparatus for encoding/decoding intra prediction mode
US9154796B2 (en) 2011-11-04 2015-10-06 Qualcomm Incorporated Intra-mode video coding
US9986238B2 (en) 2012-01-20 2018-05-29 Intellectual Discovery Co., Ltd. Intra prediction mode mapping method and device using the method
US9554130B2 (en) 2012-01-20 2017-01-24 Pantech Inc. Intra prediction mode mapping method and device using the method
US10863173B2 (en) 2012-01-20 2020-12-08 Dolby Laboratories Licensing Corporation Intra prediction mode mapping method and device using the method
WO2013109066A1 (en) * 2012-01-20 2013-07-25 주식회사 팬택 Intra prediction mode mapping method and device using the method
US10616575B2 (en) 2012-01-20 2020-04-07 Intellectual Discovery Co., Ltd. Intra prediction mode mapping method and device using the method
US10158852B2 (en) 2012-01-20 2018-12-18 Intellectual Discovery Co., Ltd. Intra prediction mode mapping method and device using the method
US9854239B2 (en) 2012-01-20 2017-12-26 Intellectual Discovery Co., Ltd. Intra prediction mode mapping method and device using the method
US10951884B2 (en) 2017-01-16 2021-03-16 Industry Academy Cooperation Foundation Of Sejong University Method and apparatus for encoding/decoding an image signal
US11533470B2 (en) 2017-01-16 2022-12-20 Industry Academy Cooperation Foundation Of Sejong University Method and apparatus for encoding/decoding an image signal
US11665337B2 (en) 2017-01-16 2023-05-30 Industry Academy Cooperation Foundation Of Sejong University Method and apparatus for encoding/decoding an image signal
US11659169B2 (en) 2018-09-13 2023-05-23 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Affine Linear Weighted Intra Predictions

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CA2488266C (en) 2013-08-13
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EP1512115A4 (en) 2009-06-03
MXPA04012133A (en) 2005-04-19
JP2005529527A (en) 2005-09-29
JP4490261B2 (en) 2010-06-23
CN100380984C (en) 2008-04-09
CN1659580A (en) 2005-08-24
TWI239207B (en) 2005-09-01
EP1512115A1 (en) 2005-03-09
AU2003240172B2 (en) 2009-09-10
KR20050007607A (en) 2005-01-19
KR101017094B1 (en) 2011-02-25
CA2488266A1 (en) 2003-12-18
DE60345459C5 (en) 2022-11-17

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