US6625323B2 — Method for compressing and decompressing digital …

Claim 1

Independent Claim 216 words

A method for compressing a digital image having both saturated text and/or line art and pictorial imagery, the method comprising the steps of: (a) receiving the digital image as blocks of pixels; (b) analyzing the block content to determine if all or any combination of the saturated text and/or line art, pictorial imagery or other types of image data are present; (c) assigning the saturated text and/or line art, the pictorial imagery, the other types of image data to one of a plurality of categories; (d) compressing the block of saturated text and/or line art, if any, according to a JPEG compression method using a first quantization matrix; (e) compressing the pictorial imagery, if any, according to the JPEG compression method while using a second quantization matrix different from the first quantization matrix; (f) compressing the other types of imagery, if any, according to the JPEG compression method corresponding to other predetermined quantization matrices different from the first quantization matrix; (g) providing information about the assigned image category for each pixel block of the digital image to a decoder; and (h) using the JPEG compression with the first, second, and other predetermined quantization matrices in steps (d)-(f) so that the first, second, and other predetermined quantization matrices minimizes any data loss resulting from the JPEG compression.

Claim 2

Independent Claim 216 words

A method for compressing a digital image having both saturated text and/or line art and pictorial imagery, the method comprising the steps of: (a) receiving the digital image as blocks of pixels; (b) analyzing the block content to determine if all or any combination of the saturated text and/or line art, pictorial imagery or other types of image data are present; (c) assigning the saturated text and/or line art, the pictorial imagery, the other types of image data to one of a plurality of categories; (d) compressing the block of saturated text and/or line art, if any, according to a JPEG compression method using a first quantization matrix; (e) compressing the pictorial imagery, if any, according to the JPEG compression method while using a second quantization matrix different from the first quantization matrix; (f) compressing the other types of imagery, if any, according to the JPEG compression method corresponding to other predetermined quantization matrices different from the first quantization matrix; (g) providing information about the assigned image category for each pixel block of the digital image to a decoder; and (h) using the JPEG compression with the first, second, and other predetermined quantization matrices in steps (d)-(f) so that the first, second, and other predetermined quantization matrices minimizes any data loss resulting from the JPEG compression.

Claim 3

Dependent Claim 23 words

The method as in claim 1 further comprising, prior to step (d), applying a contrast reducer to the saturated text and/or line art.

Claim 4

Dependent Claim 43 words

The method as in claim 1 , further comprising transmitting a code in a header for each image block which code identifies to a decoder whether the image block is saturated text and/or line art, pictorial imagery, or the other types of imagery.

Claim 5

Dependent Claim 43 words

The method as in claim 1 further comprising transmitting in the compressed image header a set of concatenated codewords which code identifies to a decoder whether each image block is saturated text and/or line art, pictorial imagery, or the other types of imagery.

Claim 6

Dependent Claim 26 words

The method as in claim 1 , wherein step (b) includes using text and pictorial images, and bi-level images as the other types of image data.

Claim 7

Dependent Claim 27 words

The method as in claim 1 further comprising determining if the block contains only values of 0 and 255 which indicates saturated text and/or line art by.

Claim 8

Dependent Claim 24 words

The method as in claim 1 further comprising determining if the block contains three unique values between 1 and 254 which indicates pictorial imagery.

Claim 9

Dependent Claim 29 words

The method as in claim 5 further comprising determining if the block contains only two unique values selected from a range of 1 to 254 which indicates bi-level image.

Claim 10

Dependent Claim 46 words

The method as in claim 5 further comprising determining if the block contains at least one value between 0 and 255 inclusive in addition to at least one value equal to 0 or 255 which indicates both saturated text and/or line art imagery and pictorial imagery.

Claim 11

Dependent Claim 93 words

The method as in claim 1 further comprising using a first 8×8quantization matrix if the block is saturated text and/or line art, wherein the first 8×8 quantization matrix is 8 8 8 8 9 10 12 14 8 8 8 8 9 10 12 15 8 8 8 9 10 12 14 32 8 8 9 11 13 15 32 32 9 9 10 13 16 32 32 32 10 10 12 15 32 32 32 32 12 12 14 32 32 32 32 32 14 15 32 32 32 32 32 32.

Claim 12

Dependent Claim 29 words

The method as in claim 5 further comprising using a second 8×8 quantization matrix if the block is bi-level, wherein the second quantization matrix is 8 at each location.

Claim 13

Dependent Claim 37 words

The method as in claim 1 further comprising using a third 8×8 quantization matrix if the block is both saturated text and/or line art, and pictorial imagery, wherein the third quantization matrix is 1 at each location.

Claim 14

Independent Claim 276 words

A method for compressing a digital image having both saturated text and/or line art and pictorial imagery, and then decompressing the digital image, the method comprising the steps of: (a) receiving the digital image as blocks of pixels; (b) analyzing the block content to determine if all or any combination of the saturated text and/or line art, pictorial imagery or other types of image data are present; (c) assigning the saturated text and/or line art, the pictorial imagery, the other types of image data to one of a plurality of categories; (d) compressing the block of saturated text and/or line art, if any, according to a JPEG compression method using a first quantization matrix; (e) compressing the pictorial imagery, if any, according to the JPEG compression method while using a second quantization matrix different from the first quantization matrix; (f) compressing the other types of imagery, if any, according to the JPEG compression method, and using a corresponding other predetermined quantization matrix different from the first quantization matrix; (g) providing information about the assigned image category for each pixel block of the digital image to a decoder, (h) using the JPEG compression with the first, second, and other predetermined quantization matrices in steps (d)-(f) so that the first, second, and other predetermined quantization matrices minimizes any data loss resulting from the JPEG compression; and (i) applying a threshold operation to the decompressed saturated text and/or line art, wherein the threshold operation converts the value of all the pixels below a predetermined threshold to a minimum pixel value and converts the value of all the pixels at or above the predetermined threshold to a maximum pixel value.

Claim 15

Independent Claim 276 words

A method for compressing a digital image having both saturated text and/or line art and pictorial imagery, and then decompressing the digital image, the method comprising the steps of: (a) receiving the digital image as blocks of pixels; (b) analyzing the block content to determine if all or any combination of the saturated text and/or line art, pictorial imagery or other types of image data are present; (c) assigning the saturated text and/or line art, the pictorial imagery, the other types of image data to one of a plurality of categories; (d) compressing the block of saturated text and/or line art, if any, according to a JPEG compression method using a first quantization matrix; (e) compressing the pictorial imagery, if any, according to the JPEG compression method while using a second quantization matrix different from the first quantization matrix; (f) compressing the other types of imagery, if any, according to the JPEG compression method, and using a corresponding other predetermined quantization matrix different from the first quantization matrix; (g) providing information about the assigned image category for each pixel block of the digital image to a decoder, (h) using the JPEG compression with the first, second, and other predetermined quantization matrices in steps (d)-(f) so that the first, second, and other predetermined quantization matrices minimizes any data loss resulting from the JPEG compression; and (i) applying a threshold operation to the decompressed saturated text and/or line art, wherein the threshold operation converts the value of all the pixels below a predetermined threshold to a minimum pixel value and converts the value of all the pixels at or above the predetermined threshold to a maximum pixel value.

Claim 16

Dependent Claim 30 words

The method as in claim 13 , wherein step (h) includes using a threshold value halfway between a minimum and maximum pixel values in the saturated text and/or line art.

Claim 17

Dependent Claim 23 words

The method as in claim 13 further comprising, prior to step (d), applying a contrast reducer to the saturated text and/or line art.

Claim 18

Dependent Claim 42 words

The method as in claim 13 further comprising transmitting a code in a header for each image block which code identifies to a decoder whether the image block is saturated text and/or line art, pictorial imagery, or the other types of imagery.

Claim 19

Dependent Claim 43 words

The method as in claim 13 further comprising transmitting in the compressed image header a set of concatenated codewords which code identifies to a decoder whether each image block is saturated text and/or line art, pictorial imagery, or the other types of imagery.

Claim 20

Dependent Claim 26 words

The method as in claim 13 , wherein step (b) includes using text and pictorial images, and bi-level images as the other types of image data.

Claim 21

Dependent Claim 27 words

The method as in claim 13 further comprising determining if the block contains only values of 0 and 255 which indicates saturated text and/or line art by.

Claim 22

Dependent Claim 24 words

The method as in claim 13 further comprising determining if the block contains three unique values between 1 and 254 which indicates pictorial imagery.

Claim 23

Dependent Claim 29 words

The method as in claim 18 further comprising determining if the block contains only two unique values selected from a range of 1 to 254 which indicates bi-level image.

Claim 24

Dependent Claim 46 words

The method as in claim 18 further comprising determining if the block contains at least one value between 0 and 255 inclusive in addition to at least one value equal to 0 or 255 which indicates both saturated text and/or line art imagery and pictorial imagery.

Claim 25

Dependent Claim 94 words

The method as in claim 13 further comprising using a first 8×8 quantization matrix if the block is saturated text and/or line art, wherein the first 8×8 quantization matrix is: 8 8 8 8 9 10 12 14 8 8 8 8 9 10 12 15 8 8 8 9 10 12 14 32 8 8 9 11 13 15 32 32 9 9 10 13 16 32 32 32 10 10 12 15 32 32 32 32 12 12 14 32 32 32 32 32 14 15 32 32 32 32 32 32.

Claim 26

Dependent Claim 29 words

The method as in claim 18 further comprising using a second 8×8 quantization matrix if the block is bi-level, wherein the second quantization matrix is 8 at each location.

Claim 27

Dependent Claim 37 words

The method as in claim 3 further comprising using a third 8×8 quantization matrix if the block is both saturated text and/or line art, and pictorial imagery, wherein the third quantization matrix is 1 at each location.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2006-09-22	2007-03-24	2007-09-23	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2010-09-22	2011-03-24	2011-09-23	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2014-09-22	2015-03-24	2015-09-23	$7700.00	Window Closed / Lapsed

Method for compressing and decompressing digital having text

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