Method and apparatus for blending images

Claim 2

A pen-based computer system comprising: a central processing unit (CPU); a display assembly having an input tablet and a display screen; a video memory responsive to said CPU for storing first and second image information sets corresponding to first and second images to be displayed on display screen, one of the first and second images corresponding to a handwritten image drawn on the input tablet; and a video driver for providing pixel state information, said video driver being connected to said video memory and being responsive to the first and second information sets in determining pixel states provided to the video display such that the pixel states provided are a function of both the first and second images, and said video driver includes a look-up table, and wherein the image information sets are presented as addresses to said look-up table and said look-up table produces the pixel states for the video display; a recognizer for attempting to recognize the handwritten image, wherein when at least a portion of the handwritten image is recognized, said video driver operates to modify at least one of the first and second image information sets stored in said video memory.

Claim 3

The computer system according to claim 1, wherein the pixel states produced by said look-up table represent a blending of the first and second images.

Claim 4

The computer system according to claim 2, wherein said video driver includes a color and/or gray scale screen controller.

Claim 5

The computer system according to claim 2, wherein said first and second images stored in said video memory are represented by four bit nibbles, and wherein the video driver provides an output signal indicative of the intended illumination of specific pixels.

Claim 6

The computer system according to claim 1, wherein said look-up table includes a plurality of addressable locations containing image tone level indications for pixels to be displayed on the video display.

Claim 7

The computer system according to claim 5, wherein said look-up table is divided into a plurality of sections, and each section provides tone level information for an associated color.

Claim 8

The computer system according to claim 6, wherein said look-up table comprises three sections, representing the respective colors, red, green, and blue, and/or gray scale hues.

Claim 9

The computer system according to claim 1, wherein said video memory includes a plurality of video RAMs, and first and second images are stored in separate video RAMs.

Claim 10

The computer system according to claim 8, wherein said plurality of video RAMs store image information in pixel pairs.

Claim 11

The computer system according to claim 1, wherein said computer system further performs an activity in accordance with the recognized portion of the handwritten image.

Claim 12

The computer system according to claim 10, wherein the activity is the execution of a command.

Claim 13

The computer system according to claim 10, wherein the activity is the display of a graphic item on the display screen.

Claim 16

The method according to claim 13, wherein first and second images are combined to establish an address location in a look-up table containing resultant pixel state information representing the combination of first and second images.

Claim 17

The method according to claim 14, wherein the entries of the look-up table comprise intensity or color tone indications.

Claim 18

The method according to claim 13, wherein each entry of the look-up table includes at least an intensity or color tone for red, green and blue.

Claim 19

The method according to claim 16, wherein said first and second image information is combined to represent a four bit contribution from said first image information and a four bit contribution from said second image information.

Claim 20

The method according to claim 13, wherein said first image information is produced from an application program.

Claim 21

The method according to claim 13, wherein said second image information is provided by a user using a pen on the input tablet.

Claim 22

The method according to claim 13, wherein said method further comprises: performing an activity in accordance with the recognized portion of the handwritten image when at least a portion of the handwritten pen-based input is recognized.

Claim 23

The method according to claim 20, wherein the activity is the execution of a command.

Claim 24

The method according to claim 20, wherein the activity is the display of a graphic item on the display screen.

Claim 25

A computer system, comprising: a video display for displaying images; an input tablet for receiving a handwritten input; an address bus having a plurality of address lines; a data bus having a plurality of data lines; a first video buffer, operatively connected to said data bus, for storing pixel data associated with a first image; a second video buffer, operatively connected to said data bus, for storing pixel data associated with a second image, the second image being formed from handwritten input; a display driver, operatively connected to said address and data buses, for controlling the loading of first and second video buffers with the pixel data from the first and second images, respectively, and for outputting resultant pixel data to said video display; a buffer selection circuit, operatively connected to said display driver, for selecting one of said first and second video buffers based on one of the address lines; a look-up table for receiving corresponding pixel data from said first and second video buffers via the selection by said buffer selection circuit, and for combining the corresponding pixel data from said first and second video buffers to produce the resultant pixel data for the video display; and a recognizer for attempting to recognize the handwritten input, wherein when at least a portion of the handwritten input is recognized, said computer system operates to delete at least a corresponding portion of the second image from the second video buffer and modifying the first image in the first video buffer.

Claim 26

A computer system, comprising: a video display for displaying images; an input tablet for receiving a handwritten input; an address bus having a plurality of address lines; a data bus having a plurality of data lines; a first video buffer, operatively connected to said data bus, for storing pixel data associated with a first image; a second video buffer, operatively connected to said data bus, for storing pixel data associated with a second image, the second image being formed from handwritten input; a display driver, operatively connected to said address and data buses, for controlling the loading of first and second video buffers with the pixel data from the first and second images, respectively, and for outputting resultant pixel data to said video display; a buffer selection circuit, operatively connected to said display driver, for selecting one of said first and second video buffers based on one of the address lines; a look-up table for receiving corresponding pixel data from said first and second video buffers via the selection by said buffer selection circuit, and for combining the corresponding pixel data from said first and second video buffers to produce the resultant pixel data for the video display; and a recognizer for attempting to recognize the handwritten input, wherein when at least a portion of the handwritten input is recognized, said computer system operates to delete at least a corresponding portion of the second image from the second video buffer and modifying the first image in the first video buffer.

Claim 27

A computer system as recited in claim 23, wherein said look-up table translucently combines the corresponding pixel data to produce the resultant pixel data.

Claim 28

A computer system as recited in claim 23, wherein said look-up table includes entries correspond to the resultant pixel data, and wherein said look-up table is addressed with the pixel data received.

Claim 29

A computer system as recited in claim 25, wherein the entries of said look-up table comprise intensity or color tone indications.

Claim 30

A computer system as recited in claim 25, wherein each entry of said look-up table includes at least an intensity or color tone for red, green and blue.

Claim 31

A computer system as recited in claim 23; wherein said display driver includes said look-up table; and wherein the pixel data are stored as sets of pixel data to said video buffers, the sets including pixel data for at least two pixels, and wherein the sets of pixel data read from said video buffers are supplied to said display driver.

Claim 32

A computer system as recited in claim 28, wherein said look-up table translucently combines the corresponding pixel data to produce the resultant pixel data.

Claim 33

The computer system according to claim 23, wherein said computer system further performs an activity in accordance with the recognized portion of the handwritten input.

Claim 34

The computer system according to claim 23, wherein the activity is the execution of a command.

Claim 35

The computer system according to claim 30, wherein the activity is the display of a graphic item on the video display.