Device and method for processing sub-picture

• US 6,556,252 B1
• Filed: 02/08/2000
• Issued: 04/29/2003
• Est. Priority Date: 02/08/1999
• Status: Expired due to Term

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Dae Joong
• Primary Examiner(s): Miller, John
• Assistant Examiner(s): DESIR, JEAN WICEL
• Application Number:
  US09/499,632
• Time in Patent Office: 1,176 Days
• Field of Search: H04/N.545, 348/565, 348/563, 348/564, 348/566, 348/567, 348/569, 348/570, 348/521, 348/523, 348/524, 348/525
• US Class Current: 348/565
• CPC Class Codes: H04N 21/43072 of multiple content streams on the same device
• CPC Class Codes: H04N 21/4316 for displaying supplemental content in a region of the screen, e.g. an advertisement in a separate window
• CPC Class Codes: H04N 21/4858 for modifying screen layout parameters, e.g. fonts, size of the windows
• CPC Class Codes: H04N 5/45 Picture in picture , e.g. displaying simultaneously another television channel in a region of the screen

Abstract

A device and method for processing a sub-picture in a TV receiver is disclosed. The present invention allows a viewer to freely move the position of a sub-picture in both left⇄right and top⇄bottom directions, such that even a portion of the sub-picture may be displayed on the screen.

Claims

1. A device for processing a sub-picture in a TV receiver, comprising:

an input signal processor which receives and processes an input data including a main picture data and a sub-picture data, said input signal processor generating main picture synchronizing signals and sub-picture synchronizing signals;

a picture-in-picture (PIP) synchronizing generator which receives the main picture synchronizing signals and generates PIP synchronizing signals;

a read timing generator which generates a read signal using the PIP picture synchronizing signals;

a write timing generator which generates a write signal using the sub-picture synchronizing signals and the PIP synchronizing signals;

a sub-sampler which selects and sub-samples a portion of the sub-picture data to be displayed according to the write signal;

a sub-picture frame memory which stores a sub-sampled sub-picture data and presents the stored sub-picture data according to the read signal; and

a multiplexer which multiplexes a decoded main picture data from the input signal processor and the sub-picture data read from the sub-picture frame memory, and outputs the multiplexed data for display.

2. A device of claim 1, wherein the PIP synchronizing generator comprises:

a line counter which receives a main picture vertical synchronizing signal MAIN_VSYNC and a main picture horizontal synchronizing signal MAIN_HSYNC, and counts a number of MAIN_HSYNC signals within an effective MAIN_V SYNC signal to output a main picture line information; and

a first calculator which receives a corner vertical point coordinate of the sub-picture and a sub-picture height information from an external source and receives the main picture line information, said first calculator generating vertical side related information of the sub-picture to be displayed using the received information.

3. A device of claim 2, wherein the first calculator generates:

synchronizing signals PIP_VSYNC of lines to be displayed as the sub-picture on the main picture;

a PIP_LINE_OFFSET signal representing a line counted starting from a top side of the sub-sampled sub-picture up to which the sub-picture is not to be displayed; and

a number of lines PIP_DISP_HEIGHT of the sub-sampled sub-picture to be displayed.

4. A device of claim 3, wherein the PIP_VSYNC signal activated is on a line at which the sub-picture is to be displayed.

5. A device of claim 3, wherein:

the PIP_LINE_OFFSET is set to −

PIP_POS_Y and the PIP_DISP_HEIGHT is set to (PIP_HEIGHT+PIP_POS_Y) if the PIP_POS_Y is smaller than  

and if the PIP_POS_Y is greater than −

PIP_HEIGHT, where PIP_HEIGHT is the height of the sub-sampled sub-picture;

the PIP_POS_Y is changed to MAIN_HEIGHT−

1, the PIP_LINE_OFFSET is changed to ‘

0’ and

the PIP_DISP_HEIGHT is changed to ‘

1,’

if the PIP_POS_Y is smaller than ‘

0’ and

if the PIP_POS-Y is smaller than or equal to −

PIP_HEIGHT, wherein MAIN-HEIGHT is the height of the main picture;

the PIP_POS_Y is changed to −

PIP_HEIGHT+1, the PIP_LINE_OFFSET is changed to PIP_HElGHT−

1 and the PIP_DISP_HEIGHT is changed to ‘

1,’

if the PIP_POS_Y is not smaller than ‘

0’ and

if the PIP_POS_Y is greater than or equal to MAIN_HEIGHT;

the PIP_LINE_OFFSET is set to ‘

0’ and

the PIP_DISP_HEIGHT is equal to PIP_HEIGHT, if the PIP_POS_Y is not smaller than ‘

0,’

if the PIP_POS_Y is smaller than MAIN_HEIGHT and if (MAIN_HEIGHT−

PIP_POS_Y) is equal to or is greater than PIP_HEIGHT; and

otherwise

the PIP_LINE_OFFSET is set to ‘

0’ and

the PIP_DISP_HEIGHT is set to (MAIN_HEIGHT−

PIP_POS_Y).

6. A device of claim 1, wherein the PIP synchronizing generator further comprises:

a pixel counter which counts a number of clock pulses in an effective MAIN_HSYNC signal to output main column information; and

a second calculator which receives a corner horizontal point coordinate of the sub-picture and a sub-picture width information from the external source and receives the main column information, said second calculator generating horizontal side related information of the sub-picture to be displayed using the received information.

7. A device of claim 6, wherein the second calculator generates:

synchronizing signals PIP_HSYNC of columns to be displayed as the sub-picture on the main picture;

a PIP_COLUMN_OFFSET signal representing a pixel counted starting from a left most side of the sub-sampled sub-picture up to which the sub-picture is not to be displayed; and

a number of pixels per line PIP_DISP_WIDTH of the sub-sampled sub-picture to be displayed.

8. A device of claim 7, wherein the PIP_HSYNC signal is activated on a column at which the sub-picture is to be displayed.

9. A device of claim 7, wherein:

the PIP_COLUMN_OFFSET is set to −

PIP_POS_X and the PIP_DISP_WIDTH is set to (PIP_WIDTH+PIP_POS_X) if the PIP_POS_X is smaller than ‘

0’ and

if the PIP_POS_X is greater than −

PIP_WIDTH, where PIP_WIDTH is the width of the sub-sampled sub-picture;

the PIP_POS_X is changed to MAIN_WIDTH−

1, the PIP_COLUMN_OFFSET is changed to ‘

0’ and

the PIP_DISP_WIDTH is changed to ‘

1,’

if the PIP_POS_X is smaller than ‘

0’ and

if the PIP_POS-X is smaller than or equal to −

PIP_WIDTH, wherein MAIN-WIDTH is the width of the main picture;

the PIP_POS_X is changed to −

PIP_WIDTH+1, the PIP_COLUMN_OFFSET is changed to PIP_WIDTH−

1 and the PIP_DISP_WIDTH is changed to ‘

1,’

if the PIP_POS_X is not smaller than ‘

0’ and

if the PIP_POS_X is greater than or equal to MAIN_WIDTH;

the PIP_COLUMN_OFFSET is set to ‘

0’ and

the PIP_DISP_WIDTH is equal to PIP_WIDTH, if the PIP_POS_X is not smaller than ‘

0,’

if the PIP_POS_X is smaller than MAIN_WIDTH and if (MAIN_WIDTH−

PIP_POS_X) is equal to or is greater than PIP_WIDTH; and

otherwise

the PIP_COLUMN_OFFSET is set to ‘

0’ and

the PIP_DISP_WIDTH is set to (MAIN_WIDTH−

PIP_POS_X).

10. A device of claim 1, wherein the write timing generator comprises:

a line counter which receives a sub-picture vertical synchronizing signal SUB_VSYNC and a horizontal synchronizing signal SUB_HSYNC, and counts a number of SUB_HSYNC signals within an effective SUB_VSYNC signal; and

a first comparator which activates a line enable signal LINE_ENABLE when a value counted by the line counter is greater than a PIP_LINE_OFFSET information and smaller than a PIP_DISP_HEIGHT, where the PIP_LINE_OFFSET represents a line counted starting from a top side of the sub-sampled sub-picture up to which the sub-picture is not to be displayed and the PIP_DISP_HEIGHT represents the number of lines of the sub-sampled sub-picture to be displayed.

11. A device of claim 10, wherein the write timing generator further comprises:

a pixel counter which receives the SUB_VSYNC signal and the SUB_HSYNC signal, and counts a number of clock pulses CLK within an effective SUB_HSYNC signal; and

a second comparator which activates a pixel enable signal PIXEL_ENABLE when the value counted by the pixel counter is greater than a PIP_COLUMN_OFFSET information and smaller than a PIP_DISP_WIDTH information, where a PIP_COLUMN_OFFSET signal represents a pixel counted starting from a left most side of the sub-sampled sub-picture up to which the sub-picture is not to be displayed and the PIP_DISP_WIDTH represents the number of columns of the sub-sampled sub-picture to be displayed.

12. A device of claim 11, wherein:

the first comparator performs a M modulo operation on the count value from the line counter to calculate a height of the sub-sampled sub-picture PIP_HEIGHT, where a quotient from the M modular operation is the PIP_HEIGHT if a remainder is ‘

0’ and

otherwise the quotient plus a value of ‘

1’

is the PIP_HEIGHT; and

the second comparator performs a N modulo operation on the count value from the pixel counter to calculate a width of the sub-sampled sub-picture PIP_WIDTH, where a quotient from the N modular operation is the PIP_WIDTH if a remainder is ‘

0’ and

otherwise the quotient plus a value of ‘

1’

is the PIP_WIDTH.

13. A method for processing a sub-picture in a TV receiver, comprising:

(a1) receiving and processing an input data including a main picture data and a sub-picture data, and generating main picture synchronizing signals and sub-picture synchronizing signals;

(b1) generating picture-in-picture (PIP) synchronizing signals using the main picture synchronizing signals;

(c1) generating a read signal using the PIP synchronizing signals;

(d1) generating a write signal using the sub-picture synchronizing signals and the PIP synchronizing signals;

(e1) sub-sampling a portion of the sub-picture data to be displayed according to the write signal;

(f1) storing a sub-sampled sub-picture data and presenting the stored sub-picture data according to the read signal; and

(g1) multiplexing a decoded main picture data and the presented sub-picture data, and outputting the multiplexed data for display.

14. A method of claim 13, wherein (b1) comprises:

(a2) receiving a main picture vertical synchronizing signal MAIN_VSYNC and a main picture horizontal synchronizing signal MAIN_HSYNC, and counting a number of MAIN_HSYNC signals within an effective MAIN_V SYNC signal to output a main picture line information; and

(b2) receiving a corner vertical point coordinate of the sub-picture and a sub-picture height information from an external source and receiving the main picture line information, and generating vertical side related information of the sub-picture to be displayed using the received information.

15. A method of claim 14, wherein (b2) generates:

synchronizing signals PIP_VSYNC of lines to be displayed as the sub-picture on the main picture;

a PIP_LINE_OFFSET signal representing a line counted starting from a top side of the sub-sampled sub-picture up to which the sub-picture is not to be displayed; and

a number of lines PIP_DISP_HEIGHT of the sub-sampled sub-picture to be displayed.

16. A method of claim 15, wherein the PIP_VSYNC signal is activated on a line at which the sub-picture is to be displayed.

17. A method of claim 15 wherein:

the PIP_LINE_OFFSET is set to −

PIP_POS_Y and the PIP_DISP_HEIGHT is set to (PIP_HEIGHT+PIP_POS_Y) if the PIP_POS_Y is smaller than ‘

0’ and

if the PIP_POS_Y is greater than −

PIP_HEIGHT, where PIP_HEIGHT is the height of the sub-sampled sub-picture;

the PIP_POS_Y is changed to MAIN_HEIGHT−

1, the PIP_LINE_OFFSET is changed to ‘

0’ and

the PIP_DISP_HEIGHT is changed to ‘

1,’

if the PIP_POS_Y is smaller than ‘

0’ and

if the PIP_POS-Y is smaller than or equal to −

PIP_HEIGHT, wherein MAIN-HEIGHT is the height of the main picture;

the PIP_POS_Y is changed to −

PIP_HEIGHT+1, the PIP_LINE_OFFSET is changed to PIP_HEIGHT−

1 and the PIP_DISP_HEIGHT is changed to ‘

1,’

if the PIP_POS_Y is not smaller than ‘

0’ and

if the PIP_POS_Y is greater than or equal to MAIN_HEIGHT;

the PIP_LINE_OFFSET is set to ‘

0’ and

the PIP_DISP_HEIGHT is equal to PIP_HEIGHT, if the PIP_POS_Y is not smaller than ‘

0,’

if the PIP_POS_Y is smaller than MAIN_HEIGHT and if (MAIN_HEIGHT−

PIP_POS_Y) is equal to or is greater than PIP_HEIGHT; and

otherwise

the PIP_LINE_OFFSET is set to ‘

0’ and

the PIP_DISP_HEIGHT is set to (MAIN_HEIGHT−

PIP_POS_Y).

18. A method of claim 14, wherein (b1) further comprises:

(c2) counting a number of clock pulses in an effective MAIN_HSYNC signal to output main column information; and

(d2) receiving a corner horizontal point coordinate of the sub-picture and a sub-picture width information from the external source and receiving the main column information, and generating horizontal side related information of the sub-picture to be displayed using the received information.

19. A method of claim 18, wherein (d2) generates:

synchronizing signals PIP_HSYNC of columns to be displayed as the sub-picture on the main picture;

a PIP_COLUMN_OFFSET signal representing a pixel counted starting from a left most side of the sub-sampled sub-picture up to which the sub-picture is not to be displayed; and

a number of pixels per line PIP_DISP_WIDTH of the sub-sampled sub-picture to be displayed.

20. A method of claim 19, wherein the PIP_HSYNC signal is activated on a column at which the sub-picture is to be displayed.

21. A method of claim 19, wherein:

the PIP_COLUMN_OFFSET is set to −

PIP_POS_X and the PIP_DISP_WIDTH is set to (PIP_WIDTH+PIP_POS_X) if the PIP_POS_X is smaller than ‘

0’ and

if the PIP_POS_X is greater than −

PIP_WIDTH, where PIP_WIDTH is the width of the sub-sampled sub-picture;

the PIP_POS_X is changed to MAIN_WIDTH−

1, the PIP_COLUMN_OFFSET is changed to ‘

0’ and

the PIP_DISP_WIDTH is changed to ‘

1,’

if the PIP_POS_X is smaller than ‘

0’ and

if the PIP_POS-X is smaller than or equal to −

PIP_WIDTH, wherein MAIN-WIDTH is the width of the main picture;

the PIP_POS_X is changed to −

PIP_WIDTH+1, the PIP_COLUMN_OFFSET is changed to PIP_WIDTH−

1 and the PIP_DISP_WIDTH is changed to ‘

1,’

if the PIP_POS_X is not smaller than ‘

0’ and

if the PIP_POS_X is greater than or equal to MAIN_WIDTH;

the PIP_COLUMN_OFFSET is set to ‘

0’ and

the PIP_DISP_WIDTH is equal to PIP_WIDTH, if the PIP_POS_X is not smaller than ‘

0,’

if the PIP_POS_X is smaller than MAIN_WIDTH and if (MAIN_WIDTH−

PIP_POS_X) is equal to or is greater than PIP_WIDTH; and

otherwise

the PIP_COLUMN_OFFSET is set to ‘

0’ and

the PIP_DISP_WIDTH is set to (MAIN_WIDTH−

PIP_POS_X).

22. A method of claim 13, wherein (d1) comprises:

(a3) receiving a sub-picture vertical synchronizing signal SUB_VSYNC and a horizontal synchronizing signal SUB_HSYNC, and counting a number of SUB_HSYNC signals within an effective SUB_VSYNC signal; and

(b3) activating a line enable signal LINE_ENABLE when a value counted in (a3) is greater than a PIP_LINE_OFFSET information and smaller than a PIP_DISP_HEIGHT, where the PIP_LINE_OFFSET represents a line counted starting from a top side of the sub-sampled sub-picture up to which the sub-picture is not to be displayed and the PIP_DISP_HEIGHT represents the number of lines of the sub-sampled sub-picture to be displayed.

23. A method of claim 22, wherein (d1) further comprises:

(c3) receiving the SUB_VSYNC signal and the SUB_HSYNC signal, and counting a number of clock pulses CLK within an effective SUB_HSYNC signal; and

(d3) activating a pixel enable signal PIXEL_ENABLE when the value counted in (c3) is greater than a PIP_COLUMN_OFFSET information and smaller than a PIP_DISP_WIDTH information, where a PIP_COLUMN_OFFSET signal represents a pixel counted starting from a left most side of the sub-sampled sub-picture up to which the sub-picture is not to be displayed and the PIP_DISP_WIDTH represents the number of columns of the sub-sampled sub-picture to be displayed.

24. A method of claim 23, further comprising:

performing a M modulo operation on the count value from the line counter to calculate a height of the sub-sampled sub-picture PIP_HEIGHT, where a quotient from the M modular operation is the PIP_HEIGHT if a remainder is ‘

0’ and

otherwise the quotient plus a value of ‘

1’

is the PIP_HEIGHT; and

performing a N modulo operation on the count value from the pixel counter to calculate a width of the sub-sampled sub-picture PIP_WIDTH, where a quotient from the N modular operation is the PIP_WIDTH if a remainder is ‘

0’ and

otherwise the quotient plus a value of ‘

1’

is the PIP_WIDTH.