Multiple picture composing method and multiple picture composing apparatus

• US 6,456,335 B1
• Filed: 10/06/1998
• Issued: 09/24/2002
• Est. Priority Date: 02/19/1998
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Miura, Tsuyoshi, Terui, Yuichi
• Primary Examiner(s): Kostak, Victor R.
• Application Number:
  US09/167,432
• Time in Patent Office: 1,449 Days
• Field of Search: 348/564, 348/588, 348/383, 348/839, 348/840, 348/159, 348/153, 348/143, 348/500, 348/512, 348/513, 348/15, 348/565, 348/567, 348/568, 348/385, 348/386, 348/584, 348/731, 348/732
• US Class Current: 348/588
• CPC Class Codes: H04N 5/2624 for obtaining an image which is composed of whole input images, e.g. splitscreen
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

A multiple picture composing method for composing video signals from a plurality of video signal sources which operate asynchronously to each other includes the steps of (a) successively selecting the video signals from the video signal sources, (b) reading the selected video signals in units of frames while maintaining horizontal and vertical synchronization of the selected video signals, (c) reducing the video signals in the units of frames in correspondence with areas allocated for each of pictures to be composed in a composed picture, (d) writing the reduced video signal in blocks of a picture composing memory corresponding to the areas allocated for each of the pictures to be composed, and (e) composing the video signals stored in the picture composing memory to obtain a composed video signal related to a composed picture and subjecting the composed video signal to at least one of an encoding process and a transmission process.

Claims

1. A multiple picture composing method for composing video signals from a plurality of video signal sources which operate asynchronously to each other, comprising the steps of:

(a) successively selecting the video signals from the video signal sources;

(b) reading the selected video signals in units of frames while maintaining horizontal and vertical synchronization of the selected video signals;

(c) reducing the video signals in the units of frames in correspondence with areas allocated for each of pictures to be composed in a composed picture;

(d) writing the reduced video signal in blocks of a picture composing memory corresponding to the areas allocated for each of the pictures to be composed; and

(e) composing the video signals stored in the picture composing memory to obtain a composed video signal related to a composed picture and subjecting the composed video signal to at least one of an encoding process and a transmission process.

2. The multiple picture composing method as claimed in claim 1, wherein said step (e) carries out at least one of the encoding process and the transmission process every time a video signal in the units of frames and to be composed is read from one of the plurality of video signal sources.

3. The multiple picture composing method as claimed in claim 1, wherein said step (b) successively reads the video signals in the units of frames from the plurality of video signal source and said step (d) writes the reduced video signal in the picture composing memory during an encoding process and/or a transmission process, and said step (e) carries out at least one of the encoding process and the transmission process with respect to the video signal stored in the picture composing memory upon completion of the encoding process and/or the transmission process.

4. The multiple picture composing method as claimed in claim 1, which further comprises the steps of:

(f) reading a video signal of a weighted channel a number of times greater than video signals of other channels and obtaining the composed video signal by writing the video signals of the weighted channel and the other channels in the picture composing memory by said step (e).

5. The multiple picture composing method as claimed in claim 1, wherein said step (a) judges existences of the video signals from the plurality of video signal sources and selects only a video signal source from which a video signal exists, and said step (d) writes only the reduced video signal from the video signal source selected by said step (a).

6. The multiple picture composing method as claimed in claim 1, which further comprises the steps of:

(f) writing a fixed pattern in a block of the picture composing memory corresponding to an invalid area on the composed picture,

said step (e) composing the video signals and the fixed pattern stored in the picture composing memory.

7. The multiple picture composing method as claimed in claim 1, which further comprises the steps of:

(f) writing a received and decoded data in a block of the picture composing memory corresponding to an invalid area on the composed picture,

said step (e) composing the video signals and the received and decoded data stored in the picture composing memory.

8. The multiple picture composing method as claimed in claim 1, which further comprises the steps of:

(f) writing an enlarged video signal of a weighted channel in a block of the picture composing memory corresponding to an invalid area on the composed picture,

said step (e) composing the video signals and the enlarged video signal stored in the picture composing memory.

9. The multiple picture composing method as claimed in claim 1, which further comprises the steps of:

(f) writing a video signal of a weighted channel in a block of the picture composing memory corresponding to an invalid area on the composed picture so as to make a zoom-up display of the video signal of the weighted channel.

10. The multiple picture composing method as claimed in claim 1, wherein said step (e) carries out the encoding process by setting a quantization value with respect to a video signal of a weighted channel to a small value with priority.

11. The multiple picture composing method as claimed in claim 1, wherein said step (e) carries out an intra-frame encoding process with respect to a video signal of a weighted channel, and carries out an inter-frame prediction coding process with respect to video signals of other channels.

12. The multiple picture composing method as claimed in claim 1, which further comprises the steps of:

(f) disabling an in-loop filter when carrying out an encoding process with respect to a video signal of a weighted channel, and enabling the in-loop filter when carrying out an encoding process with respect to video signals of other channels.

13. The multiple. picture composing method as claimed in claim 1, which further comprises the steps of:

(f) setting a motion estimation search range with respect to a video signal of a weighted channel to a first range, and discontinuing the motion estimation search range or setting the motion estimation search range with respect to video signals of other channels to a second range smaller than the first range.

14. The multiple picture composing method as claimed in claim 10, which further comprises the steps of:

(g) selecting a channel which is to be weighted based on resolution information of the plurality of video signal sources and frame rate information.

15. The multiple picture composing method as claimed in claim 10, which further comprises the steps of:

(g) obtaining moving quantity information corresponding to the video signals from the plurality of video signal sources, and weighting a channel having a moving quantity greater than a predetermined value based on the moving quantity information.

16. The multiple picture composing method as claimed in claim 1, wherein said step (d) writes reduced video signals from the plurality of video signal sources in the units of frames, further comprising the steps of:

(f) enabling an in-loop filter when said step (e) carries out the encoding process with respect to the video signals immediately after said step (d) writes the video signals, and disabling the in-loop filter when said step (e) carries out the encoding process with respect to the video signal of a previous frame.

17. The multiple picture composing method as claimed in claim 1, wherein said step (a) selects a number of channels of video signal sources depending on a number of pictures to be composed when the number of pictures to be composed is greater than a number of video signal sources, and said step (b) switches a channel of the video signal which is read for every predetermined time.

18. The multiple picture composing method as claimed in claim 1, which further comprises the steps of:

(f) transmitting, together with a layout of pictures to be composed, a guidance which includes specifying a picture composing process,

said step (e) carrying out the picture composing process specified according to the guidance.

27. The multiple picture composing method as claimed in claim 11, which further comprises the steps of:

(g) selecting a channel which is to be weighted based on resolution information of the plurality of video signal sources and frame rate information.

28. The multiple picture composing method as claimed in claim 12, which further comprises the steps of:

(g) selecting a channel which is to be weighted based on resolution information of the plurality of video signal sources and frame rate information.

29. The multiple picture composing method as claimed in claim 13, which further comprises the steps of:

(g) selecting a channel which is to be weighted based on resolution information of the plurality of video signal sources and frame rate information.

30. The multiple picture composing method as claimed in claim 11, which further comprises the steps of:

(g) obtaining moving quantity information corresponding to the video signals from the plurality of video signal sources, and weighting a channel having a moving quantity greater than a predetermined value based on the moving quantity information.

31. The multiple picture composing method as claimed in claim 12, which further comprises the steps of:

(g) obtaining moving quantity information corresponding to the video signals from the plurality of video signal sources, and weighting a channel having a moving quantity greater than a predetermined value based on the moving quantity information.

32. The multiple picture composing method as claimed in claim 13, which further comprises the steps of:

(g) obtaining moving quantity information corresponding to the video signals from the plurality of video signal sources, and weighting a channel having a moving quantity greater than a predetermined value based on the moving quantity information.

19. A multiple picture composing apparatus for composing video signals from a plurality of video signal sources which operate asynchronously to each other, comprising:

a video signal selector selecting the video signals from the video signal sources;

an input signal monitoring unit reading the video signals selected by said video signal selector while maintaining horizontal and vertical synchronization of the selected video signals;

a horizontal direction reducer reducing the video signals synchronized by said input signal monitoring unit in units of frames in correspondence with areas allocated for each of pictures to be composed in a composed picture;

a picture composing memory storing the video signals reduced by said horizontal direction reducer in units of lines;

a picture composing controller controlling reading of the video signals by said input signal monitoring unit via said video signal selector and a picture composing process with respect to the video signals stored in said picture composing memory; and

an encoder carrying out the picture composing process with respect to the video signals stored in said picture composing memory.

20. The multiple picture composing apparatus as claimed in claim 19, which further comprises:

an encoding controller controlling said encoder to carry out the encoding process every time said input signal monitoring unit reads the video signals from the video signal sources in the units of frames.

21. The multiple picture composing apparatus as claimed in claim 19, wherein said picture composing controller controls said video signal selector so that a video signal of a weighted channel is read by said input signal monitoring unit a number of times greater than a number of times video signals of other channels are read.

22. The multiple picture composing apparatus as claimed in claim 19, which further comprises:

video input judgement means for judging whether or not the video signals from the plurality of video signal sources exist,

said picture composing controller controls said video signal selector to read only a video signal from a video signal source from which said input judging means judges an existence of the video signal and controls positions of blocks of the video signals to be composed in said picture composing memory.

23. The multiple picture composing apparatus as claimed in claim 19, wherein said encoding controller controls at least one of a quantization value with respect to a video signal corresponding to a weighted channel in said encoder, switching of an intra-frame encoding process and an inter-frame prediction coding process in said encoder, and enabled and disabled states of an in-loop filter in the encoder.

24. The multiple picture composing apparatus as claimed in claim 19, which further comprises:

special data storing memory storing a fixed pattern which is to be stored in a block of said picture composing memory corresponding to an invalid area on the composed picture.

25. The multiple picture composing apparatus as claimed in claim 19, which further comprises:

a decoder decoding received data; and

a decoding memory storing received data decoded by said decoder and to be stored in a block of said picture composing memory corresponding to an invalid area on the composed picture.

26. The multiple picture composing apparatus as claimed in claim 24, wherein said picture composing controller carries out a control to temporarily store a video signal of a weighted channel in said special data storing memory, and to store the video signal stored in said special data storing memory into said picture composing memory so as to make a zoom-up display of the video signal stored in said special data storing memory.