US5699475A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for encoding a digital image signal
Assignee: Sony Corp
•
Filing: 1993-02-02
•
Granted: 1997-12-16
•
Expires: 2013-02-02
Abstract
Abstract A digital image signal is encoded for recording by placing in a sync block approximately an integer number of macro blocks representing orthogonally transformed image data for a certain portion of the image. When a sync block is reproduced at high speed, the reproduced data therein corresponds to a displayable portion of the image including DC components and both low and high frequency AC components. Also, each sync block contains fixed length areas for the orthogonal transform coefficient data according to the 4:1:1 (or 4:2:0) format in which four blocks of luminance coefficients and two blocks of color difference coefficients represent a certain portion of an image, and also contains at least one fixed length overflow area for the high frequency coefficients which exceed the capacity of the fixed length coefficient areas. An error in the low frequency coefficients in the fixed length areas does not harm the high frequency coefficients since they are in separately addressed areas. Before a set of macro blocks is compressed into variable length encoded data, with the amount of encoded data for each set being kept within a target value so as to fit into fixed length recording tracks, the macro blocks are shuffled so that the central portions of an image are at the beginning of the set for reducing the noticeability of errors in a reproduced image.
Inventors
- 👤 Masaki Oguro
- 👤 Naofumi Yanagihara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:01
CPC Classifications
H; H04; H04N; H04N21/00; H04N21/20; H04N21/23; H04N21/238; H04N21/2387; H04N9/00; H04N9/79; H04N9/80; H04N9/804; H04N9/8042; H04N9/8047; H04N11/00; H04N11/04; H04N11/042; H04N11/044; H04N19/00; H04N19/10; H04N19/102; H04N19/124; H04N19/134; H04N19/136; H04N19/14; H04N19/146; H04N19/149; H04N19/169; H04N19/17; H04N19/176; H04N19/18; H04N19/60; H04N19/85; H04N19/89; H04N21/236; H04N21/40; H04N21/43; H04N21/434; H04N7/00; H04N7/24; H04N5/00; H04N5/76; H04N5/78; H04N5/782; H04N5/783
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
198 words
A method for encoding a digital image signal, comprising the steps of: orthogonally transforming said digital image signal into transformed macro blocks containing DC, low frequency AC and high frequency AC components of said digital image signal, encoding an encoding set comprised of a predetermined number of said transformed macro blocks using a variable length code into an amount of encoded data in accordance with a target amount, and forming said encoded data corresponding to an approximately integer number of said transformed macro blocks into a first sync block having a fixed length and also having DC component areas and low frequency AC component areas at predetermined positions and at least one high frequency AC component area at least at one predetermined position, with the encoded data representing said DC and low frequency AC components being in said DC and low frequency AC component areas, respectively, and at least some of the encoded data representing said high frequency AC components being placed in said at least one high frequency AC component area in the first sync block and remaining encoded data representing said high frequency AC components exceeding said fixed length being placed in a second sync block.
Claim 2
Independent Claim
198 words
A method for encoding a digital image signal, comprising the steps of: orthogonally transforming said digital image signal into transformed macro blocks containing DC, low frequency AC and high frequency AC components of said digital image signal, encoding an encoding set comprised of a predetermined number of said transformed macro blocks using a variable length code into an amount of encoded data in accordance with a target amount, and forming said encoded data corresponding to an approximately integer number of said transformed macro blocks into a first sync block having a fixed length and also having DC component areas and low frequency AC component areas at predetermined positions and at least one high frequency AC component area at least at one predetermined position, with the encoded data representing said DC and low frequency AC components being in said DC and low frequency AC component areas, respectively, and at least some of the encoded data representing said high frequency AC components being placed in said at least one high frequency AC component area in the first sync block and remaining encoded data representing said high frequency AC components exceeding said fixed length being placed in a second sync block.
Claim 3
Dependent Claim
35 words
The method of claim 1; further comprising the steps of blocking said digital image signal into image data blocks, and shuffling a spatial sequence of said image data blocks before said step of orthogonally transforming.
Claim 4
Dependent Claim
82 words
The method of claim 2; wherein, a predetermined number of said image data blocks form a respective shuffling set of macro blocks, and, in said step of shuffling, central macro blocks of each said shuffling set which correspond to central portions of an image represented by said digital image signal are shuffled to precede other macro blocks of the respective shuffling set which correspond to other portions of said image that are less centrally located in said image than said central portions.
Claim 5
Dependent Claim
28 words
The method of claim 1; wherein said step of orthogonally transforming includes performing a discrete cosine transformation on said digital image signal to produce said transformed macro blocks.
Claim 6
Dependent Claim
51 words
The method of claim 1; wherein said step of encoding includes estimating a quantizing number for said encoding set based on said target amount, quantizing said macro blocks in said encoding set in accordance with said quantizing number, and variable length coding the quantized macro blocks using said variable length code.
Claim 7
Dependent Claim
39 words
The method of claim 1; wherein said first sync block also includes a data area having a starting position, and said at least one high frequency AC component area is located near said starting position of said data area.
Claim 8
Independent Claim
368 words
A method for encoding a digital image signal, comprising the steps of: orthogonally transforming said diqital image signal into transformed macro blocks containing DC and low frequency AC components of said digital image signal; encoding an encoding set comprised of a predetermined number of said transformed macro blocks using a variable length code into an amount of encoded data in accordance with a target amount, said transformed macro blocks being respectively comprised of a predetermined number of transformed image data blocks which each contain AC component data representing high frequency AC components and said low frequency AC components; and forming said encoded data corresponding to an approximately integer number of said transformed macro blocks into a sync block having a fixed length and also having DC component areas and low frequency AC component areas at predetermined positions and at least one high frequency AC component area at least at one predetermined position, with the encoded data representing said DC and low frequency AC component being in said DC and low frequency AC component areas, respectively, and at least some of the encoded data representing said high frequency AC components being placed in the at least high frequency AC component area in said sync block, and with the number of said low frequency AC component areas in said sync block being equal to said predetermined number of transformed image data blocks in each of said transformed macro blocks, said step of forming including first placing AC component data of one of said transformed image data blocks in a transformed macro block into a respective one of said low frequency AC component areas until said respective one of said low frequency AC component areas is filled, next placing further AC Component data of said one of said transformed image data blocks which exceeds the capacity of said respective one of said low frequency AC component areas into said high frequency AC component area and unused areas of other of said low frequency AC component areas which contain AC component data for other of said transformed image data blocks, and finally placing as yet unplaced AC component data of said one of said transformed image data blocks into another sync block.
Claim 9
Independent Claim
368 words
A method for encoding a digital image signal, comprising the steps of: orthogonally transforming said diqital image signal into transformed macro blocks containing DC and low frequency AC components of said digital image signal; encoding an encoding set comprised of a predetermined number of said transformed macro blocks using a variable length code into an amount of encoded data in accordance with a target amount, said transformed macro blocks being respectively comprised of a predetermined number of transformed image data blocks which each contain AC component data representing high frequency AC components and said low frequency AC components; and forming said encoded data corresponding to an approximately integer number of said transformed macro blocks into a sync block having a fixed length and also having DC component areas and low frequency AC component areas at predetermined positions and at least one high frequency AC component area at least at one predetermined position, with the encoded data representing said DC and low frequency AC component being in said DC and low frequency AC component areas, respectively, and at least some of the encoded data representing said high frequency AC components being placed in the at least high frequency AC component area in said sync block, and with the number of said low frequency AC component areas in said sync block being equal to said predetermined number of transformed image data blocks in each of said transformed macro blocks, said step of forming including first placing AC component data of one of said transformed image data blocks in a transformed macro block into a respective one of said low frequency AC component areas until said respective one of said low frequency AC component areas is filled, next placing further AC Component data of said one of said transformed image data blocks which exceeds the capacity of said respective one of said low frequency AC component areas into said high frequency AC component area and unused areas of other of said low frequency AC component areas which contain AC component data for other of said transformed image data blocks, and finally placing as yet unplaced AC component data of said one of said transformed image data blocks into another sync block.
Claim 10
Independent Claim
202 words
An apparatus for encoding a digital image signal, comprising: means for orthogonally transforming said digital image signal into transformed macro blocks containing DC, low frequency AC and high frequency AC components of said digital image signal, means for encoding an encoding set comprised of a predetermined number of said transformed macro blocks using a variable length code into an amount of encoded data in accordance with a target amount, and framing means for forming said encoded data corresponding to an approximately integer number of said transformed macro blocks into a first sync block having a fixed length and also having DC component areas and low frequency AC component areas at predetermined positions and at least one high frequency AC component area at least at one predetermined position, with the encoded data representing said DC and low frequency AC components being in said DC and low frequency AC component areas, respectively, and at least some of the encoded data representing said high frequency AC components being placed in said at least one high frequency AC component area in the first sync block and remaining encoded data representing said high frequency AC components exceeding said fixed length being placed in a second sync block.
Claim 11
Independent Claim
202 words
An apparatus for encoding a digital image signal, comprising: means for orthogonally transforming said digital image signal into transformed macro blocks containing DC, low frequency AC and high frequency AC components of said digital image signal, means for encoding an encoding set comprised of a predetermined number of said transformed macro blocks using a variable length code into an amount of encoded data in accordance with a target amount, and framing means for forming said encoded data corresponding to an approximately integer number of said transformed macro blocks into a first sync block having a fixed length and also having DC component areas and low frequency AC component areas at predetermined positions and at least one high frequency AC component area at least at one predetermined position, with the encoded data representing said DC and low frequency AC components being in said DC and low frequency AC component areas, respectively, and at least some of the encoded data representing said high frequency AC components being placed in said at least one high frequency AC component area in the first sync block and remaining encoded data representing said high frequency AC components exceeding said fixed length being placed in a second sync block.
Claim 12
Dependent Claim
38 words
The apparatus of claim 8; further comprising means for blocking said digital image signal into image data blocks, and means for shuffling a spatial sequence of said image data blocks before said image data blocks are orthogonally transformed.
Claim 13
Dependent Claim
79 words
The apparatus of claim 9; wherein a predetermined number of said image data blocks form a respective shuffling set of macro blocks, and said means for shuffling shuffles central macro blocks of each said shuffling set which correspond to central portions of an image represented by said digital image signal to precede other macro blocks of said shuffling set which correspond to other portions of said image that are less centrally located in said image than said central portions.
Claim 14
Dependent Claim
27 words
The apparatus of claim 8; wherein said means for orthogonally transforming performs a discrete cosine transformation on said digital image signal to produce said transformed macro blocks.
Claim 15
Dependent Claim
57 words
The apparatus of claim 8; wherein said means for encoding includes means for estimating a quantizing number for said encoding set based on said target amount, means for quantizing said macro blocks in said encoding set in accordance with said quantizing number, and means for variable length coding the quantized macro blocks using said variable length code.
Claim 16
Dependent Claim
39 words
The apparatus of claim 8; wherein said first sync block also includes a data area having a starting position, and said at least one high frequency AC component area is located near said starting position of said data area.
Claim 17
Independent Claim
377 words
An apparatus for encoding a digital image signal, comprising: means for orthogonally transforming said digital image signal into transformed macro blocks containing DC and low frequency AC components of said digital image signal; means for encoding an encoding set comprised of a predetermined number of said transformed macro blocks using a variable length code into an amount of encoded data in accordance with a target amount, said transformed macro blocks being respectively comprised of a predetermined number of transformed image data blocks which each contain AC component data representing high frequency AC components and said low frequency AC components; and framing means for forming said encoded data corresponding to an approximately integer number of said transformed macro blocks into a sync block having a fixed length and also having DC component areas and low frequency AC component areas at predetermined positions and at least one high frequency AC component area at least at one predetermined position, with the encoded data representing said DC and low frequency Ac components being in said DC and low frequency AC component areas, respectively, and at least some of the encoded data representing said high frequency AC components being placed in the at least high frequency AC component area in said sync block, and with the number of said low frequency AC component areas in said sync block being equal to said predetermined number of transformed image data blocks in each of said transformed macro blocks, said framing means including first means for placing AC component data of one of said transformed image data blocks in a transformed macro block into a respective one of said low frequency AC component areas until said respective one of said low frequency AC component areas is filled, second means for placing further AC component data of said one of said transformed image data blocks which exceeds the capacity of said respective one of said low frequency AC component areas into said high frequency AC component area and unused areas of other of said low frequency AC component areas which contain AC component data for other of said transformed image data blocks, and third means for placing as yet unplaced AC component data of said one of said transformed image data blocks into another sync block.
Claim 18
Independent Claim
377 words
An apparatus for encoding a digital image signal, comprising: means for orthogonally transforming said digital image signal into transformed macro blocks containing DC and low frequency AC components of said digital image signal; means for encoding an encoding set comprised of a predetermined number of said transformed macro blocks using a variable length code into an amount of encoded data in accordance with a target amount, said transformed macro blocks being respectively comprised of a predetermined number of transformed image data blocks which each contain AC component data representing high frequency AC components and said low frequency AC components; and framing means for forming said encoded data corresponding to an approximately integer number of said transformed macro blocks into a sync block having a fixed length and also having DC component areas and low frequency AC component areas at predetermined positions and at least one high frequency AC component area at least at one predetermined position, with the encoded data representing said DC and low frequency Ac components being in said DC and low frequency AC component areas, respectively, and at least some of the encoded data representing said high frequency AC components being placed in the at least high frequency AC component area in said sync block, and with the number of said low frequency AC component areas in said sync block being equal to said predetermined number of transformed image data blocks in each of said transformed macro blocks, said framing means including first means for placing AC component data of one of said transformed image data blocks in a transformed macro block into a respective one of said low frequency AC component areas until said respective one of said low frequency AC component areas is filled, second means for placing further AC component data of said one of said transformed image data blocks which exceeds the capacity of said respective one of said low frequency AC component areas into said high frequency AC component area and unused areas of other of said low frequency AC component areas which contain AC component data for other of said transformed image data blocks, and third means for placing as yet unplaced AC component data of said one of said transformed image data blocks into another sync block.
References Cited (Backward Citations)
EP0239076A2
Cited
JPS62248393A
Cited
US5047852A
Cited
US5068744A
Cited
US5198900A
Cited
US5237424A
Cited
US5351131A
Cited
US5272528A
Cited
US5329375A
Cited
EP0553560A2
Cited
US5231486A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-12-15 | 2001-06-16 | 2001-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-12-15 | 2005-06-16 | 2005-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-12-15 | 2009-06-16 | 2009-12-16 | $7700.00 | Window Closed / Lapsed |