Renesas Electronics Corporation

Renesas Technology Corp.

Fumitaka Izuhara

Hiroaki Nakata

Takafumi Yuasa

Kazushi Akie

Seiji Mochizuki

Kenichi Iwata

Hiroshi Ueda

Keisuke Matsumoto

Koji Hosogi

Tetsuya Shibayama

Masakazu Ehama

Yukifumi Kobayashi

Masaru Hase

Shohei Saito

Motoki Kimura

Variable length code decoding device for decoding variable length code data, including: decoding process tables each including at least two kinds of formats consisting a first format storing identification information for designating a subsequent table to be referred to in a subsequent decoding process, and a second format that stores a decoded value obtained by repeating the decoding process and a significant bit length to be referred to with respect to variable length code data. The device utilizes first, second, third and fourth formats and relative addresses.

Variable length code decoding device and decoding method

The present invention provides an image encoding device which does not necessitate reference of a quantization parameter between consecutive macroblocks across a parallel processing area boundary without forming slices. The image encoding device encodes a macroblock of an encoding target image by parallel processing sequentially from the top of a parallel processing area, and possesses an encoding element for every parallel processing area. When all the quantized orthogonally-transformed coefficients of a top macroblock of the parallel processing area are zero, the encoding element adds a non-zero coefficient to a part of the coefficients, making the coefficients non-zero. Accordingly, generation of a skip macroblock in the top macroblock of each parallel processing area is suppressed. Since slice formation is not necessary, the prediction over a parallel processing area boundary is applied, and encoding efficiency improves. Errors are not generated in decoding and the decoded image quality does not deteriorate.

Parallel processing image encoding device with variable length coding

A variable length code decoding device for decoding variable length code data, including: a table memory that stores a plurality of decoding process tables having a reference relationship therein; and a decoding control unit that sequentially selects the decoding process tables according to the decoded data to control a process of decoding the variable length code data, wherein when referring to the decoding process table to perform an initial decoding of the variable length code data, the initial decoding process is conducted by a longer bit length to be clipped from the variable length code data for referring to the decoding process table than the bit length used when referring to the other portions of the decoding process table.

The present invention provides a functional block that executes video coding and video decoding based on H.264/AVC. The functional block includes two moving picture processing units, and a memory unit that stores therein data related to the results of processing of first plural macroblocks arranged within one row of one picture by the first moving picture processing unit. Data related to the results of processing of plural adjacent macroblocks, which are selected from the data stored in the memory unit, are transferred to the second moving picture processing unit. The second moving picture processing unit performs processing of one macroblock of second plural macroblocks arranged in the following row, using the transferred data.

Parallel processing circuit for intra-frame prediction

The present invention provides a technology that is implemented in a motion compensation image coding device or a coding method and intended to code motion picture data in real time by performing a decreased number of arithmetic operations so as to determine a motion vector. In motion compensation image coding, macroblocks and sub-blocks into which each of the macroblocks is divided are searched for a motion vector with integer pixel precision. Based on the results of the search, a shape of a block that should be searched for a motion vector with decimal pixel precision is determined as a shape mode. The block of the shape mode is searched for a motion vector with decimal pixel precision, whereby a motion vector needed to produce predictive image data is determined.

Motion compensation image coding device and coding method

A variable length code decoding device for decoding variable length code data, including: a table memory that stores a plurality of decoding process tables having a reference relationship therein; and a decoding control unit that is given a start address and an initial reference bit length of the table memory; and sequentially selects the decoding process tables according to the decoded data to control a process of decoding the variable length code data, wherein when referring to the decoding process table to perform an initial decoding of the variable length code data, the initial decoding process is conducted by a longer bit length to be clipped from the variable length code data for referring to the decoding process table than the bit length used when referring to the other portions of the decoding process table.

A flag indicating whether a decoding process is completed or continued is disposed in each of entries of a decoding process table. A decoded value and a significant bit length are recorded in the entry of a decoding process completion. Information for identifying the decoding process table which is used in a subsequent process, and a bit length that is clipped from a code word which is used when referring to a subsequent table are recorded in the entry of the decoding process continuation. When the decoding process starts, the information for identifying the table to be used and the bit length that is referred to from the code word when referring to the table are designated together with the code word. The decoding process table reference is repeated as the occasion demands. With the above configuration, there is provided a variable length code decoding device.

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Kokubunji, Japan

Fumitaka Izuhara