Wide-band multi-format audio/video production system with frame-rate conversion

• US 6,370,198 B1
• Filed: 05/06/1999
• Issued: 04/09/2002
• Est. Priority Date: 04/07/1997
• Status: Expired due to Term

• Current Assignee: Lightside Technologies, LLC
• Original Assignee: Kinya Washino
• Inventors: Washino, Kinya
• Primary Examiner(s): Le, Vu
• Application Number:
  US09/305,953
• Time in Patent Office: 1,069 Days
• Field of Search: 348/441, 348/445, 348/448, 348/426, 348/432, 348/454, 348/558, 348/568, 348/555-556, 348/722, 348/911, 348/575, 358/527, 358/524, 375/240.26, 375/240.29
• US Class Current: 375/240.26
• CPC Class Codes: G11B 20/10527 Audio or video recording; Data buffering arrangements G11B20/12 - G11B20/18 take precedence
• CPC Class Codes: G11B 20/1262 with more than one format/standard, e.g. conversion from CD-audio format to R-DAT format
• CPC Class Codes: G11B 2020/1292 Enhancement of the total storage capacity
• CPC Class Codes: G11B 2220/20 Disc-shaped record carriers
• CPC Class Codes: G11B 2220/218 Write-once discs
• CPC Class Codes: G11B 2220/2516 Hard disks
• CPC Class Codes: G11B 2220/2545 CDs
• CPC Class Codes: G11B 27/031 Electronic editing of digitised analogue information signals, e.g. audio or video signals
• CPC Class Codes: G11B 27/034 on discs G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/105 of operating discs
• CPC Class Codes: H04N 19/40 using video transcoding, i.e. partial or full decoding of a coded input stream followed by re-encoding of the decoded output stream
• CPC Class Codes: H04N 21/440218 by transcoding between formats or standards, e.g. from MPEG-2 to MPEG-4 conversion of standards in analogue television systems H04N7/01
• CPC Class Codes: H04N 5/222 Studio circuitry; Studio devices; Studio equipment cameras or camera modules comprising electronic image sensors, or control thereof H04N23/00
• CPC Class Codes: H04N 5/2228 Video assist systems used in motion picture production, e.g. video cameras connected to viewfinders of motion picture cameras or related video signal processing
• CPC Class Codes: H04N 5/46 for receiving on more than one standard at will deflecting circuits of multi-standard receivers H04N3/27
• CPC Class Codes: H04N 5/772 the recording apparatus and the television camera being placed in the same enclosure
• CPC Class Codes: H04N 5/781 on disks or drums
• CPC Class Codes: H04N 5/85 on discs or drums
• CPC Class Codes: H04N 5/91 Television signal processing therefor
• CPC Class Codes: H04N 7/01 Conversion of standards , e.g. involving analogue television standards or digital television standards processed at pixel level
• CPC Class Codes: H04N 7/011 : using magnetic recording
• CPC Class Codes: H04N 7/0112 : one of the standards corresponding to a cinematograph film standard
• CPC Class Codes: H04N 7/0122 : the input and the output signals having different aspect ratios
• CPC Class Codes: H04N 7/0125 : one of the standards being a high definition standard
• CPC Class Codes: H04N 7/0127 : by changing the field or frame frequency of the incoming video signal, e.g. frame rate converter
• CPC Class Codes: H04N 9/7921 : for more than one processing mode
• CPC Class Codes: H04N 9/7925 : for more than one standard
• CPC Class Codes: H04N 9/82 : the individual colour picture signal components being recorded simultaneously only

Abstract

A multi-format digital video production system enables a user to process an input video program to produce an output version of the program in a final format which may have a different frame rate, pixel dimensions, or both. An internal production format of 24 fps is preferably chosen to provide the greatest compatibility with existing and planned formats associated with HDTV standard 4:3 or widescreen 16:9 high-definition television, and film. Images are re-sized horizontally and vertically by pixel interpolation, thereby producing larger or smaller image dimensions so as to fill the particular needs of individual applications. Frame rates are adapted by inter-frame interpolation or by traditional schemes, including “3:2 pull-down” for 24-to-30 fps conversions. Simple speed-up (for 24-to-25 conversions) or slow-down (for 25-to-24 conversions) for playback, or by manipulating the frame rate itself using a program storage facility with asynchronous reading and writing capabilities. The step of converting the signal to a HDTV format is preferably performed using a modified upconversion process for wideband signals (utilizing a higher sampling clock frequency) and a resizing to HDTV format frame dimensions in pixels. The present invention thus encourages production at relatively low pixel dimensions to make use of lower-cost general-purpose technology and to maintain high signal-to-noise ratio, and then subsequently expands the resultant image into a so-called up-converted program. This is in contrast to alternative approaches, which recommend operating at HDTV-type resolution, then down-converting, as necessary, to smaller image formats.

Claims

1. A method of producing a video program, comprising the steps of:

receiving an input video program in an input format;

converting the input video program into a digital production format by sampling the input program at a sampling frequency in excess of 18 megahertz;

providing high-capacity digital video storage means equipped with an asynchronous program recording and reproducing capability to perform a frame-rate conversion; and

processing the video program in the production format using the high-capacity video storage means on a selective basis to output a version of the video program having a desired frame rate and image dimensions in pixels.

2. The method of claim 1, wherein the production format uses a frame rate of 24 frames per second.

3. The method of claim 1, wherein the step of processing the video program in the production format includes the use of pixel interpolation.

4. The method of claim 1, wherein the output version of the program has image dimensions pixels of 1024×

576;

1280×

720;

or 1920×

1080.

5. The method of claim 4, using a sampling frequency of up to 37 Mhz at the image dimensions of 1024×

576 and 1280×

720.

6. The method of claim 4, using a sampling frequency of up to 74.25 Mhz at the image dimension of 1920×

1080.

7. The method of claim 1, wherein the input video program is standard or widescreen NTSC or PAL.

8. The method of claim 1, wherein the output version of the program is standard or widescreen NTSC or PAL.

9. The method of claim 1, wherein the step of receiving an input video program includes receiving the program from a camera having 600 or more lines of resolution.

10. The method of claim 1, further including the step of storing the program in data-compressed form.

11. The method of claim 10, wherein the compression scheme is MPEG-2.

12. The method of claim 1, wherein the step of processing the video program in the production format includes the use of 4:

2;

2 10-bit processing.

13. The method of claim 1, wherein the frame rate of the output version of the program is higher than one or both of the input and production formats.

14. The method of claim 1, wherein the frame rate of the output version of the program is lower than one or both of the input and production formats.

15. The method of claim 1, wherein the high-capacity digital video storage means includes an asynchronous read/write capability used to perform a frame-rate conversion.

16. The method of claim 1, wherein the step of processing the video program in the production format includes the use of line doubling or quadrupling.

17. A method of producing an enhanced definition video program, comprising the steps of:

receiving a standard definition television (SDTV) program from a source having a resolution capability of 600 or more lines;

converting the input video program into a digital production format by sampling the input program at a sampling frequency in excess of 18 megahertz;

providing high-capacity digital video storage means equipped with an asynchronous program recording and reproducing capability to perform a frame-rate conversion;

storing the program in data compressed form; and

processing the program in the production format to output an enhanced definition version of the program having a desired frame rate and image dimensions in pixels.

18. The method of claim 17, wherein the production format uses a frame rate of 24 frames per second.

19. The method of claim 17, wherein the SDTV program is standard or widescreen NTSC or PAL.

20. The method of claim 17, wherein the enhanced definition version of the program has image dimensions in pixels of 1024×

576;

1280×

720;

or 1920×

1080.

21. The method of claim 20, using a sampling frequency of up to 37 Mhz at image dimensions of 1024×

576 and 1280×

720.

22. The method of claim 20, using a sampling frequency of up to 74.25 Mhz at an image dimension of 1920×

1080.

23. The method of claim 17, wherein the source is a video camera.

24. The method of claim 17, wherein the compression scheme is MPEG-2.

25. The method of claim 17, wherein the step of processing the video program in the production format includes the use of 4:

2;

2 10-bit processing.

26. The method of claim 17, wherein the frame rate of the enhanced definition version of the program is higher than one or both of the input and production formats.

27. The method of claim 17, wherein the frame rate of the enhanced definition version of the program is lower than one or both of the input and production formats.

28. The method of claim 17, wherein the step of processing the video program in the production format includes the use of pixel interpolation.

29. The method of claim 17, wherein the step of processing the video program in the production format includes the use of line doubling or quadrupling.