Apparatus and method of smoothing MAPS compressed image data

• US 4,598,372 A
• Filed: 12/28/1983
• Issued: 07/01/1986
• Est. Priority Date: 12/28/1983
• Status: Expired due to Term

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: McRoberts, Louis A.
• Primary Examiner(s): Gruber, Felix D.
• Application Number:
  US06/566,258
• Time in Patent Office: 916 Days
• Field of Search: 364/514, 364/518, 364/521, 364/900, 358/133, 358/160, 358/166, 358/167, 358/260, 382/56
• US Class Current: 345/555
• CPC Class Codes: H04N 1/409 Edge or detail enhancement; Noise or error suppression

Abstract

MAPS compressed image data is arranged symmetrically so that it can be stored in a substantially reduced memory and operated on for smoothing with substantially less components. A serial and a parallel design are disclosed, both of which have substantially reduced memories and a reduced number of stages for processing of the surround areas.

Claims

1. A method of smoothing MAPS compressed image data including video data and coefficients for a central block of pixels and video data and coefficients for a plurality of surround areas, said method comprising the steps of:

arranging coefficients for surround areas CS₁ through CS_i symmetrically so they are divided into at least two equal groups;

storing the coefficients of one of the equal groups in an order coinciding with the arranging step;

retrieving stored coefficients by accessing the stored coefficients in a first sequence for one of the equal groups and accessing the stored coefficients in an opposite sequence for the other of the equal groups; and

utilizing the retrieved coefficients and the video data to calculate the output value for any pixel (n) in the central block of pixels from the equation ##EQU2## Where;

D=video data for the central block,

C_n =coefficient for the central block,

DS_i =video data for the surround areas 1 through i, and

CS_i =coefficient for the surround areas 1 through i;

and

applying the calculated output value to display apparatus to produce an image from the compressed image data.

2. A method as claimed in claim 1 wherein the storing step includes storing the coefficients in a binary addressable memory and the retrieving step includes generating binary numbers wherein the least significant bits are the address and the most significant bit indicates the equal group being accessed.

3. A method as claimed in claim 1 wherein the storing step includes storing the coefficients in an addressable memory and reducing the amount of memory utilized by dividing the addressable memory into independent sections, dividing the surround areas into groups with each group containing at least two surround areas which are never accessed simultaneously and storing coefficients for the surround areas in each group in a different section of the addressable memory.

4. A method of reducing the amount of memory utilized in storing information, comprising the steps of:

arranging the information symmetrically so it is divided into two equal groups;

storing the information of one of the equal groups in an order coinciding with the arranging step;

retrieving stored information by accessing the stored information in a first sequence for one of the equal groups and accessing the stored information in an opposite sequence for the other of the equal groups.

5. A method as claimed in claim 4 wherein the storing step includes storing the information in an addressable memory, dividing the addressable memory into independent sections, dividing the information into groups with each group containing at least two sets of information which are never accessed simultaneously and storing each group in a different section of the addressable memory.

6. Apparatus for smoothing MAPS compressed image data including video data and coefficients for a central block of pixels and video data and coefficients for a plurality of surround areas, said apparatus comprising:

addressble memory means having stored therein coefficients for the plurality of surround areas, the coefficients being arranged symmetrically so they are divided into two equal groups with the coefficients for one of the equal groups being stored in said memory means;

address generating means connected to said addressable memory means for generating binary numbers the least significant bits of which are the address of the stored coefficient being accessed and the most significant bit of which determines the equal group being accessed; and

circuitry connected to said memory means and said address generating means for calculating the output values for any pixel (n) in the central block of pixels from the equation ##EQU3## where;

D=video data for the central block,

C_n =coefficient for the central block,

DS_i =video data for the surround areas 1 through i, and

CS_i =coefficient for the surround areas 1 through i.

7. Apparatus as claimed in claim 6 wherein the addressable memory means further includes a plurality of separately addressable sections, the surround areas are divided into groups with each group containing at least two surround areas which are never accessed simultaneously and coefficients for the surround areas in each group are stored in different sections of said addressable memory.

8. Apparatus as claimed in claim 7 wherein the circuitry includes a stage of apparatus for each group of surround areas and the stages are coupled together to provide continuous processing of the video data.

9. Apparatus as claimed in claim 8 wherein there are twelve surround areas divided into five groups and the circuitry includes a stage for processing the video data and coefficients of the central block and five stages for processing the video data and coefficients of the five groups.