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AssigneeU.S. Phillips Corporation
InventorsPeter H. N. De With, Stephanus J. J. Nijssen, Robert A. Brondijk, Wilhelmus H. A. Bruls
Estimating the term…
To be able to transmit television pictures in a digital form through a medium having a limited bandwidth, the pictures are subjected to picture transform and to variable-length coding. The picture to be transmitted is converted in this manner into a bit stream comprising code words of variable length. This bit stream is converted into a channel bit stream which is less sensitive to transmission errors. To this end the most significant code words (representing the average luminance and the coarse picture details) of sub-pictures of 8*8 pixels are accommodated at fixed bit positions of the channel bit stream. These code words can be retrieved by simple count-down of the bit positions. The other code words are distributed over the other bit positions. The decoder is relatively simple because the length of each block comprising significant code words is also transmitted. This length is preferably adapted to the extent of picture detail in the sub-picture.
A storage medium on which a picture signal is stored in the form of a digital data stream comprising a series of data blocks comprising code words of variable length, each data block having a variable length and being divided into a main block having a variable length and comprising only selected code words and a sub-block having a variable length and comprising other code words, the digital data stream comprising:
A storage medium in which a picture signal, represented as a series of data blocks comprising code words of variable length, is stored in a coded format, the coded format comprising:
A storage medium in which a picture signal is stored in a predetermined format, the picture signal comprising a series of data blocks, each of said data block comprising code words of variable length, each said data block being divided into a main block of a variable length comprising selected code words of most significance and a sub-block of a variable length comprising other code words of least significance, the predetermined format comprising a sequential series of channel blocks, each of said channel blocks having a beginning bit located at a predetermined position within the storage medium, a plurality of the main blocks being stored adjacent to each other and at a predetermined position within said storage medium determined by said beginning bit of said each channel block, a length code indicative of the length of each of said main blocks being stored at a fixed predetermined position within each said main block, and the code words of the sub-blocks being stored at remaining positions of said channel blocks, whereby decoding of code words and/or End Of Block code detection are not needed to distinguish between said main blocks and said sub-blocks.
A storage medium in which a picture signal is stored in a predetermined format, the picture signal comprising a series of data blocks, each of said data blocks comprising code words of variable length, each said data block being divided into a main block of a variable length comprising selected code words of most significance and a sub-block of a variable length comprising other code words of least significance, the predetermined format comprising a sequential series of channel-blocks, each of said channel blocks having a beginning bit located at a predetermined position within the storage medium, each of the main blocks being stored in a different one of said channel blocks and at a predetermined position within said storage medium relative to said beginning bit of said different one of said channel blocks, a length code indicative of the length of each said main block being stored at a fixed predetermined position within each said main block, and the code words of the sub-blocks being stored at remaining positions of said channel blocks, whereby decoding of code words and/or End Of Block code detection are not needed to distinguish between said main blocks and said sub-blocks.
Dependencies are inferred from the claim text.