XR 4 6 33 s 295 United States Patent (19) 11) Patent Number: 4,633,293 Powers 45) Date of Patent: Dec. 30, 1986 54 HIGH DEFINITION TELEVISION SIGNAL Primary Examiner-Michael A. Masinick FOR FILM-TELEVISION STANDARDS Attorney, Agent, or Firm-Eugene M. Whitacre; Paul J. CONVERSION SYSTEM Rasmussen; Joseph J. Laks (75) Inventor: Kerns H. Powers, Princeton, N.J. (57) ABSTRACT 73 Assignee: RCA Corporation, Princeton, N.J. A high definition television production system gener ates a high definition video signal that is easily convert (21) Appl. No.: 639,662 ible to signals formatted in accordance with other tele 22 Filed: Aug. 13, 1984 vision and film standards of release media. Such other standards may include 525/60 and 625/50 formats and 30 Foreign Application Priority Data film formats having a frame rate of 24 film frames per Sep. 26, 1983 GB United Kingdom ................. 8325689 second. The HDTV system employs vertical line scan Apr. 26, 1984 GB) United Kingdom ................. 841.0659 ning in the camera to generate the HDTV signal. The horizontal field scanning rate is chosen to be the lowest 51) Int. Cl........ ... H04N 11/20; H04N 7/01 common integral multiple of the frame rates of the re 52 U.S. Cl. ...................................... 358/11; 358/140; lease standards of interest. The interlace factor is se 358/54; 358/214 lected high enough to provide good temporal sampling 58) Field of Search ................... 358/11, 140, 54, 214, and to result in a vertical line scanning frequency that 358/216 yields an integral number of HDTV scan lines in the field or frame time of the release standards. The video (56) References Cited sampling rate is selected to be compatible with the 13.5 U.S. PATENT DOCUMENTS megahertz digital world standard studio rate. 3,617,626 11/1971 Bluth .................................... 178/5.4 4,449,143 5/1984 Dischert et al. ...................... 358/11 13 Claims, 16 Drawing Figures (INE RATE FIELD RATE (FRAMERATE) MONITOR mrak U.S. Patent Dec. 30, 1986 Sheet 1 of 12 4,633,293 F. G. 1. SHOOTING TRANSMISSION DISPLAY RATE RATE RATE CAMERA CHANNE OSPLAY F. G. 2. U.S. Patent Dec. 30, 1986 Sheet 2 of 12 4,633,293 TABLE OF LUMINANCE SIGNAL PARAMETERS ACTIVE IMAGE SAMPLE GRD 756x398 ASPECT RATIO 85 SCANNING DIRECTION WERTICAL TOTAL NUMBER SAMPLES/LINE 900 TOTAL NUMBER LINES/FRAME 1500 NUMBER LINES/FIELD OO INTERLACEFACTOR 5: NTERLACE SEQUENCE 1-4 (n-1) MODULO 15 FRAMERATE, H, 40 LINE RATE, Fy 60,000 FIELD RATE, F: 600 SAMPLING RATE, MHz 5. ANALOG BANDWIDTH, MHz 22.0 F. G. 3. U.S. Patent Dec. 30, 1986 Sheet 3 of 12 4,633,293 HORIZONAL F. GG. A. FED SCANNING DIRECTION 2 3 k 5 9 3 9 k 9 5 9 9 O O t 2? 2 2232 11MH 22MH: O.G. FLT. RESPONSE HPF RESPONSE FG 11. F. G.12. U.S. Patent Dec. 30, 1986 Sheet 4 of 12 4,633,293 I F. G. 5, 5 NERLACE FACTOR = 5: 3 d INTERACE SEQUENCE 12 I = (1+...(n-MOD 15 s 2 3 4 5 6 7 8 9 O 2 3 4 5 FIELD NUMBER F G 6. HDTV SGNAL OO A. : 2 : 2 FORMAT Y LUMNANCE SIGNAL OOC R-Y B-Y CHROMINANCE SIGNAL 1 OOb --16. 66Js-- H-1 vertical line U.S. Patent Dec. 30, 1986 Sheet 5 of 12 4,633,293 7 R 7) , (B-Y HD W OD). CAMERA Mr. 7. CLOCK X 2 X 2 5 . COMPRESS COMPRESS 78 MUX y = SOKH HDT Y HD TV (LINE RATE) 77 -- 00 SH TAPE if 600 Hz. 97 Y 98 - 5 (FIELD RATE) 100a OO Ob F-8 SE SYNC f = 40 Hz UMA INSERT. N-99 FRAME RATE) 82 Sy S Sf R G MONTOR B F. G. 7 HDTV SYSTEM 70 U.S. Patent Dec. 30, 1986 Sheet 6 of 12 4,633,293 W]|} H3080]38 ‘SS3308d 69 U.S. Patent Dec. 30, 1986 Sheet 7 of 12 4,633,293 el5 ---- | No.t:[831][10] ¤)-----¬=====–1}}r-————————————————— –?| 99100|| [eum]] U.S. Patent Dec. 30, 1986 Sheet 11 of 12 4,633,293 p29 -TWN9||S- A10H 4,633,293 1. 2 Frame B, appears in distinct positions as illustrated by HIGH DEFINTON TELEVISION SGNAL FOR the solid outlines. If one were to interpolate between FILM-TELEVISION STANDARDS CONVERSION frames to an intermediate frame at, say, 60 percent of SYSTEM the time differential, one would like to see the object at about 60 percent of the spatial distance between the This invention relates to high definition television objects in successive input frames, as illustrated by the signals and the generating and processing thereof. dashed outline. No amount of amplitude interpolation In the early days of television, the majority of the between coincident pixels on two successive frames or programs aired were movies played through a telecine on a small number of successive frames could be ex machine. The only live programming was newscaster 10 pected to yield an exact result, yet such is the manner by shots in the studio, special variety shows, and an occa which today's frame-rate converters interpolate. sional sports feature aired live. The live programming Of course, FIG. 1 is an exaggeration of the real case, was shot by television cameras operating on the 525 as at normal temporal sampling rates in both film and line, 60-field-per-second, 2:1 interlaced scanning NTSC television, the object will have moved a shorter distance standard (525/60) in the United States and a similar 15 between frames. Amplitude interpolation yields a 625/50 CCIR standard in Europe. The 24-frame per smeared double (or multiple) image, a less severe effect second movies were converted in the United States in than two sharp, distinct, widely separated images. In the telecine machines by the 3-2 pulldown technique. fact, to avoid or minimize the effect of strobing, i.e., Three fields of a given frame of the film were scanned when an object in sharp focus appears to jerk across the followed by two fields on the next successive frame. In 20 field of view through distinct positions, film cameramen Europe, the films were simply run faster, at 25 frames make sure that the aperture of the lens is open for a per second, and the 4-percent error in speed was toler sufficiently long fraction of the frame time so that the ated, even though the sound channel pitch was in image smears as it exposes the film over its path. The creased by the same factor. blurred image gives the subjective effect of continuous There was little thought of program interchangeabil 25 rather than jerky motion, as the eye does not discern ity between the 525/60 and 625/50 areas of the world in high resolution in moving objects. In television, strob any medium other than film until the advent of the ing does not often occur because the frame is interlaced communication satellite which provided world-wide so that the effective motion rate is twice the frame rate, distribution of program material in electronic form. and in addition, many television camera pickup tubes Digital standards conversion equipments were then 30 have lag that smears the image over several fields of developed but these are costly and the converted sig SC2. nals display jerk artifacts from the frame rate conver Higher degrees of interlace, e.g., 3:1, 4:1, and even 5:1 SOS. could improve the temporal sampling rate, but it is well Presently, programs produced with the intention to known that higher-order interlace generates severe distribute through multiple media are shot on film. A 35 line-crawl effects when displayed to the viewer. On the major drawback of producing on film is the long turn other hand, a frame store may be incorporated in the around time during shooting and editing. Advantages, display to reduce the line-crawl effects of interlace by however, are higher definition and the existence of refreshing all lines on the display progressively with world-standard film formats. each field. A need thus exists for a common world-standard high 40 This concept leads to the notion that the display rate definition television (HDTV) system for electronic and, indeed, the camera scanning rate (shooting rate) as production of programs and features. Such a system well, may be separated from the transmission rate, as should have simple convertibility to film, to 525/60, and illustrated in FIG. 2. The information in the frame store to 625/50 television standards with minimum loss of at the camera end is updated at the shooting rate, quality and minimal motion artifacts. Electronic pro 45 whereas the transmitted signal may be chosen to be sent duction should be done at higher resolution (horizon at a different, lower transmission rate, for example, to tally, vertically, and temporally) than any of the in match the characteristics of the channel. Similarly, the tended release media to maintain quality during the display update rate may be substantially higher than the post-production (editing) processing. transmission rate to reduce such effects as large-area Other desirable characteristics of a world-standard 50 and interline flicker. system are: An inventive arrangement provides for a high defini 1. Nearly equal facility for conversion to 525/60, tion television system that generates a video signal suit 625/50, and film. able for conversion to a first television format having 2. Balanced vertical and horizontal resolution, for N1, e.g. 525, raster lines per frame and a frame rate of maximum flexibility in post-production.