摘要:
Today the storage of audiovisual (AV) data on storage media employs standardized coding schemes, e.g. MPEG-2. End user devices for AV presentation, like disc players, contain dedicated decoders implemented in hardware, which are able to decode data streams complying with the respective standard. The efficiency of this decoding methodology relies on the standardization of appropriate coding schemes. Proprietary coding schemes may be more efficient by being adapted to the content, or may be used for content protection or optional features. Using reconfigurable decoder hardware, storing the configuration data for the actual decoder on the same storage medium as the AV data, and downloading the data to configure the player can be used to implement proprietary coding schemes. Such schemes require appropriate player hardware, suitable to execute a downloaded decoder under real-time conditions, and a standardized format to store the decoder configuration data.
摘要:
A set top box can be connected to a DVD Streamer via an IEEE1394 interface which contains means to timestamp data and to strip off these timestamps again, using them for timing regeneration. The DVD stream also must regenerate the timing of data packets as it was upon recording, when these packets are played back. The streamer could also use its own timestamps and strip them off again when replaying. So, in total, there is an in-series connection between two time stamping and time regeneration mechanism which introduces jitter accumulation.
摘要:
A cassette for use with a recording apparatus comprises: a housing for a recording medium, the housing having a first surface and side walls, the recording medium being accessible through one of the side walls; at least a part of a chip card affixed to the housing, forming a second surface of the housing and closing the cassette, the chip card part having a memory formed integrally therewith and externally accessible contacts; and, the contacts of the chip card being positioned on the second surface to be engageable by corresponding contacts in the recording apparatus when the cassette is inserted therein. One of the side walls has an access door for the recording medium and the second surface forms an upper wall of the housing as defined by the access door. The part of the chip card forming the second surface of the housing has a marking position at which light transmissivity can be controlled. The marking position can be rendered non transmissive to light to prevent recording.
摘要:
A noise reduction system with motion detection for digitalized video signals, the system including at least one memory, a filter, a correction circuit, and an adder and/or subtracter, wherein the correction circuit weights differences and/or sums of luminance and/or chrominance values with a factor k, and wherein the factor k has positive or negative values depending upon the difference in the signals.
摘要:
In bitstream recording presentation data is organized into Video Object Units. These have a variable size but have also a variable duration. To allow access to any Video Object Unit in the bitstream a housekeeping address table is used which is based on pieces of the bitstream of constant size per piece. The address table additionally contains for each of these pieces a specific delta duration which indicates the time difference between the arrival time of the first packet of a piece and the arrival time of the packet following immediately the last packet of that piece. The computation of the target VOBU address includes the following steps: accumulate the delta durations until the given time value is most closely reached towards the target VOBU; the running index of this table entry multiplied by the constant piece size directly results in the address value to be accessed.
摘要:
In a system for generating a compatible television signal with a "letterbox" display format, groups of vertically arranged picture elements (pels) are subjected to vertical DCT transformation producing eight DCT coefficients. Intermediate sixth and seventh coefficients are placed in the letterbox bar regions. The remaining six coefficients, namely the first through fifth coefficients and the highest frequency eighth coefficient, are inverse DCT transformed and processed with the main image information. A standard aspect ratio receiver displays a letterbox image using only the remaining six coefficients. A wide aspect ratio receiver uses the six remaining coefficients with the two coefficients from the bar regions, after inverse DCT, to produce a full resolution wide aspect ratio image.
摘要:
A method of signal processing batch-bulk coded digital signals which are segmented into variable-length words and the variable-length words are allocated to constant-length blocks. The constant-length blocks which receive a variable-length word having a word length which is shorter than a predetermined word length are filled up with portions of variable-length words having a word length longer than the predetermined word length. Several successive constant-length blocks are combined into superblocks, and one address word which identifies the superblock location is added at one end of each superblock. The sum of the variable-length words within each superblock is smaller than, or equal to, the sum of the constant-length blocks within the superblock.
摘要:
In bitstream recording presentation data is organized into Video Object Units. These have a variable size but have also a variable duration. To allow access to any Video Object Unit in the bitstream a mapping list is used which is based on pieces of the bitstream of constant size per piece. The mapping list additionally contains for each of these pieces a specific delta duration which indicates the difference between the arrival time of the first packet of a piece and the arrival time of the packet following immediately the last packet of that piece, and contains an initialization value which allows to have a share of equal bits between a predetermined amount of MSBs of application time stamps and the same amount of LSBs of the summation of said delta time durations. The computation of the target SOBU address includes accumulating the initialization value and the delta durations until the given time value is most closely reached towards the target SOBU then multiplying the running index of this table entry by the constant piece size directly resulting in the address value to be accessed.
摘要:
A method of making a hierarchical estimate of image motion for a television signal. A television signal video image is divided into blocks of fixed size, and motion relative to a second video image is determined for each block. Mutually non-overlapping pixel blocks are produced at a lower, more finely resolved hierarchical level. The center points of these blocks are used as the points for an analysis at a level that is located higher in the hierarchy. Preferably, points which lie between image lines and which do not represent real picture elements in the line raster, are investigated in the mutually non-overlapping blocks.
摘要:
Video signal information derived from a high definition source is conveyed via two channels. A first channel conveys relatively low spatial resolution, high temporal resolution video information compatible with a standard television receiver. An auxiliary second channel conveys relatively high spatial resolution, low temporal resolution video information. A high definition television receiver reconstructs original high definition information from the first and second channel information.