CA2123995C - In-station television program encoding and monitoring system and method - Google Patents

Abstract

An in-station method and apparatus for encoding television programs, including commercials, with a digital identification code recorded on a selected video scan line which is not normally visible to the television viewer, and far verifying the proper air-ing of such programs by such television broadcast station. The encoding and decoding is performed at the broadcast station dur-ing its normal operating procedure. The program is encoded (23) during the normal dubbing procedure (17, 19, 21) when a pro-gram video tape is dubbed to a video cartridge for use by the broadcast station's library management system (15). The decoder (31, 33) is located either at the station at an off-air monitor, or at the transmitter (29), where it monitors the transmitted signal from the broadcast station and records the occurrence of encoded programs or commercials. The information generated is stored locally for later transmission to a host computer where the information can be combined with information from other broadcast stations and other databases.

Description

W() g3/ap63~ ~'CT/US92/'~062 IN'-STATION TEhEVISION PROGRAri ENCODING
~1ND MONITORING SYSTEM AND HETEOD
BACKGROUND OF THE INVENTION
This invention relates generally to in-station methods and apparatus for automatically encoding television __ programs and for $cquiring information about the airing of such encoded television programs. This information may then 7.0 be Combined with information from other databases and reports may be compiled for use by broadcast stations, advertisers and advertising agencies.
The normal pxactice for monitoring and verifying the transmission of television programs, such as commercials, has been to video record a set -of broadcast stations in each market and then manually to re~riew and record the information from the video tapes for program or commercial occurrences.
The infonaation is then manually loaded into a computer data base manager for compilation into various reports for the broadGaat station. Such auditing is very, time consuming, laborious and expensive, so that:only the larger markets are .,_r~.. ~ ' ' , :~t-x .": ,_;:< ,~; ::, , . ... . .
m~nito~ed full time,~With smaller markets being monitored ~nly ," ~, .
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one~week of each month: sample auditing of this type is unreliable.for a number of reasons, including the fact that it ~5 is not always easy to identify a particular commercial uniquely or to differentiate it from a similar ones.

PGT/iJS92/10062 1 1W~ 93l10f~30 Furthermore, because the auditing is not automated, there is a considerable delay in reporting the information back to the broadcast stations and advertisers.
The television picture in the NTSC system used in the United States consists of a series of frames', each having 520 video scan lines: Each frame consists of two visually interlaced'temporarily sequential fields of 260 scan lines each. Each field begins with a vertical sync pulse which is followed by 260 horizontal sync pulses that define the beginning of each video scan line of the field. The horizontal sync pulse'for each line starting with line 10 is immediately followed by a 3.6 megahertz color burst signal ',rhich in turn, is followed by a "black level" voltage level referred to as the aback porch.'° Starting'with scan line 22, video information for the particular scan line foil~ws the back porch: Lines 1Q through 20 are referred to as the vertical blanking. interval and are not used for television picture information. They may be used;.if desired, by the television broadcast.station for its purposes. nine 21 is _. _ r:, .
used 'for. c~losed~ captions. ~ In mosttelevision receivers, lines .
1~ through about 30 are not visible to the viewer and are referred to as the ''overscan .region:"
Various schemes have been proposed for automatically monitoring the airing ~g television programs; such as but not limited to commercials. l~ccording to some of these schemes, en identification code is recorded on one or more sban lines of the programs to be monitored in the overscan region. U.S.
Patent No. 4,805;020 to Greenberg describes one such system in W~ 93/10630 PGT/US92I10062 which 'each field of the program is encoded with an identifying code by an encoding location before or at the time the tape is duplicated for distribution to broadcast stations in various markets. Remote monitoring systems in each market monitor a plurality of channels being transmitted and detect the encoded programs in order to assemble data on the time, duration, channel and quality of transmission of the program for use in preparing reports: a According to another such scheme, a pattern recognition system monitors the video signal or display of the program being broadcast and seeks to match the program with electronically stored program signals. These systems require large computer systems and are not reliable or accurate enough for fully automatic user The above automatic systems have not found wide commercial acceptance, for a number of reasons. For systems monitoring cable transmission, if the local cable goes down the entire monitoring system becomes inoperative. For systems -~= .monitoring vbroadcast signals,v it is : frequently difficult to 2p 'find ~-a location ~ suitable ~ fos monitoring~~:stations in the .area. Frequently it may be difficult to receive the signals of orte or more broadcast station at a given location.
Furthermore, it is necessary to go to every program originator to encode the programs to be monitored by the system. Since, foar instance, there are a'very large number of program ~riginators for-commercials, this bec~mes very cumbersome.
There are often several handling steps between the encoding of the program and its ultimate broadcast or cable transmission 9~V~ 93/10630 PC'f/US92/10062 ~~2~9~~ .

by a television station. It is therefore difficult to ensure that the identification code will not be stripped out, written over, or otherwise made unusable. Furthermore, since the amount of information available to such a monitoring and verification system is limited, the reports that~the system is able to generate are.whseful to only a limited number of potential customers:' There has been a long-felt need for a reliable, automated, quick and total accumulation of broadcast program 1Q and commercial occurrence information, which would serve the ends of a wide group of users, including broadcast stations, advertisers and others.
SUMMITRY OF THE INVENTION
In accordance with the present invention, there is provided an in-station system and method for encoding and monit~orxng the transmission of television programs at a broadcast station which includes an input video tape drive for glaying the tape containing a program received at the br~adeast .rstation, ~: ygaical.l~ by .satellite : transmission ~or on ~~p . video tape::: .:~~An ~encoc~er: is ~ cougled to the output r of the video tape drive for encoding the received program~with identifying data on a selected line of the overscan region of the video information signal. An'output video cartridge recorder is pr~vided for recording the encoded program on a video cartridge which is compatible with the video tape library maatagement system used by the station. A video tuner/decoder receives and monitors the composite signal transmitted by the broadcast station for detecting the presence of the identification codes on the encoded line of the transmitted signal. Database means are provided for storing information concerning the programs to be transmitted by the station and information from such tuner/decoder specifying the identity, 5 time of transmission, duration and transmission quality of encoded programs transmitted by the station. Also provided are means for coupling the database means to a remote host computer for transmitting data concerning the programs to be broadcast and actually broadcast by the station for the preparation of reports by such host computer.
The invention may be summarized according to one aspect as an in-station system for automatically encoding and monitoring the transmission of television programs at a television station, said station having a video library management system, comprising, at the station: an input video player for playing a recorded storage medium containing a program received at the station; an encoder coupled to the output of said video player for encoding the video information signal of said received program with identifying data; a video recorder coupled to said encoder for recording said encoded program onto a video storage medium compatible with the station's video library management system; database means for storing information concerning the recorded encoded programs; a tuner/decoder for receiving the programs transmitted by such station and for detecting the presence of such identifying data on the video information signal of said received programs; and means for storing information concerning the identity and transmission of encoded programs in said database means.
According to another aspect the invention provides a system for automatically monitoring and verifying the transmission of television programs by a television station 5a having a video library management system, an in-station method of encoding such programs comprising the steps performed at the station of: receiving programs to be broadcast by such station; dubbing such received programs onto a storage medium compatible with such video library management system: encoding the video portion of such received programs with an identifying code simultaneously with the dubbing of such program onto said medium and storing information concerning said dubbed encoded programs in database means at the station.
According to yet another aspect thc= invention provides an in-station system for automatically encoding and monitoring the transmission of television programs by a station having a video management system, comprising at the station: means for encoding programs received at said station with identifying information and for dubbing the encoded programs to a storage medium compatible with the video library management system; means for rE~ceiving the video signal of programs transmitted by said station; means for detecting the presence of said identifying information on said video signal; means for separating said identifying information from said received video signal; and data base means for storing information concerning the identity and transmission of said encoded programs.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1 is a block diagram showing the organization of a television broadcast station incorporating the encoding and monitoring system of the il7~~ustrated embodiment of the invention.

5b Figure 2 is a block diagram of the encoder system in accordance with the illustrated embodiment of the invention.
Figure 3 is a schematic diagram of the encoder of the illustrated embodiment of the invention.
Figure 4 is a block diagram of an .alternative encoding arrangement in accordance with the invention.
Figure 5 is a block diagram of the decoder system in accordance with the illustrated embodiment of tree invention.
Figure 6 is a schematic diagram of a decoder in accordance with the invention.

W~ 93/10630 PCT/US92/10062 DETAILED DESCRIPTIOid Referring now to Figure 1 of the drawings, there is illustrated a block diagram showing the relevant portions of a television broadcast station 1l. A program, which might be a commercial or other program material, may be reeeived at a television station in the.form of a video tape shipped to the station, or it may be transmitted electronically by satellite.
In the case of satellite transmission, the program is. recorded as received at the station on video tape. In either case, the video tape is delivered to the station's traffic department and information, which in the case of a commercial would typically include the title, advertiser, advertising agency, identifying codes and duration of the commercial, is ent~.ered into ~e traffic, computer 13 and matched against data concerning a related contract or program schedule stored therein.
After being processed by the traffic department, in the case ~f a commercial, the video tape is sent to the ~ngineeri~eg department,, ;to :be dubbed . onto . a type cartridge which:~:is compatible with:- he station's video tape library management system l5. In the embodiment, illustrated in Fig.
1, the dubbing is performed under the control of a dubbing computer 17 by an input video tape drive 19 which is coupled to a video cartridge recorder 21.
Depending on the equipment being used at the particular station, the tapes sent to be dubbed may be accompanied by a digital floppy disk or a handwritten dubbing information foraa. Alternatively, if the station is so ;:: ~' . :-.:. . . '_. ::y ~. , ~ _ ~; .:-. r': , .-,.- ;:::.
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~~~3~~5 equipped, the information from the traffic department may be transferred by local area network between the traffic computer 13 and the dubbing computer 17. Typically, such pertinent information about the program recorded on the video tape includes, in the case of a commercial, the ISCI--code or episode code; the name and duration of the program, the advertiser, and the advertising agency. The traffic computer also normally specifies the number of the cartridge on which the tape is to be dubbed.
The dubbing computer 17 controls the input video tape drive 19, which is typically a reel-to-reel machine, and the output video cartridge recorder 21 to dub the program from the video tape onto a video tape cartridge. Information concerning a plurality of commercials is normally sent to the dubbing computer 1? at one time by the traffis department by means of the floppy disk ~r local area network. The dubbing operator calls up the data on the dubbing computer 17 relevant to the program recorded on the next video tape to be dubbed.
This - information -is typ~.cally used t~ prepare .a . label .for the v- duDabedcartradge - on which ahe. program is ' recorded:; and :is :.:
stored in an inventor database managed by,the dubbing computer 17.. The label may contain various information depending on the station set up and equipment. The label information normally a.ncludes, however, the number of the cartridge assigned by the traffic computer in both human and machine readable form:
The dubbing computer 17, the input video tape drive 19 and the output video tape cartridge recorder 21 are iW0 93I~0630 FCT/US92/10062 , normally standard components commonly used in television broadcast stations for dubbing incoming programs for the library management system 15. Tape drives suitable for use as the input tape drive 19 are available from suppliers such as Ampex, Sony and RCA. Cartridge recorders suitable for use as the output video tape, cartridge recorder 21 are available from Sony, Ampex and other suppliers. The format and configuration of the video tape cartridge should be compatible with the s video tape library management system 15 as will be described in more detail below. The dubbing computer 17 can typically be a 38~ level personal computer or similar machine. The computer programs resident in the dubbing computer 17 for controlling the video tape drives l9 and 21 and for mainta~,ning the inventory database are commercially available from the suppliers of video tape library management systems.
It is a significant feature of the in-station encoding and monitoring system of the present invention that its use and operation is largely transparent to station .. operators:,and.:.does:.not require changes .in normal procedures..
2,D In , aGCOrdance::~:with the: preferred embodiment ~ of: the invention, , the encoding of incoming programs with an identification code for later detection during broadcast is accomplished simultaneously with the dubbing of the program onto the cartridge by means of the encoder system 23 which is connected between the output of the video tape drive 19 and the input of th,~ tape cartridge recorder 21 for encoding a selected line of the overscan region of the program°s video signal with an identification code: The identification code and other .. ... . ._; ....:: . _ .. .: : .
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infor~aation needed for the encoding is sent to the encoding system 23 by the dubbing computer 17. After being encoded, depending on how soon the program is to be broadcast and the capacity of the video tape library management system 15, the cartridges are either stored in the managemen~~~system 15 or in the station's video cartridge library in a location determined by the number assigned by the traffic computer.
The video tape library management system 15 includes a plurality of video tape drives atypically 6 to 8), a storage system for storing a plurality of tape cartridges, and a robotic system for automatically selecting cartridges from the storage system and loading each selected cartridge onto one of the tape drives for g~laying the commercial recorded thereon.
After the commercial has run, the robotic system removes the g5 cartridge from the drive and returns it to the proper location in the storage system: An elaborate cartridge library management system can store and control as many as 1,000 tape cartridges, each havia~g recorded thereon a single commercial.
~.~ typscal-.networkraffiliate. br~adcast stati~n: will have about 2,~00 t~pevcartradges in its inventory, each such cartridge storing a single commercial. An~independent television broadcast statian will typically have about 1,000 - 1,500 of ' such cartridges in its inventory. A primary network broadcast station may have 10,000 or more cartridges. Video tape library management systems are part of a television station's normal equipment and are available from various suppliers, ' such. as Sony, 7~a Kart and Ampex.

4'V~ 93/1~63 PCTlUS92/~1~062 _ 1~_.
.. As used herein a "station" may refer to a broadcast or cable network originating station or to a network affiliate or independent broadcast station. '°Hroadcast" can refer to -either broadcast or cable transmission.
Periodically, a play list is sent by the traffic computer l3 to the library management system 15 by floppy disk or local area network: The play list is an ordered listing the numbers of the video tape'containing cartridges which are to be broadcast by the station during a particular time ~.0 period. The library manage~aent system 15 compares the play list with its list of the cartridges which ~.t has stored and prints out a list of the numbers of the cartridges which it is missing.; If the library management system internal storage space is full, it selects the stored cartridges which it has not played for the longest period of time and ejects a sufficient numbarof those cartridges to make room for the needed new ones. As the new cartridges are inserted into the library management system, the robotic system rearis the ..y.~.~machine readable..numberr~y.(normally..9a=:bar .code) and -.stores it in ;..
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The output of the video tape labrary management system 15 is connected to a video swa.tcher 25, which selects amobg various inputs to be connected to the transmitter 27.
When broadcasting commercials, the video tape management system-is connected by the video switcher 25 to the transmitter 27: Other inputs to the video switcher 25 typically would include a network feed (for network affiliated stations), a connection from the station's newsroom, and a ' ~: - , ,.:, ,_,~ ; . .;.. . , _ . .::: ' .: :: : :_. :: ;...~. . :~:;.
VV~ 93/I0630 FGT/US92/10062 connection for video taped syndicated shows, among others.
The transmitter 27 broadcasts the television programs by means of the antenna 29.
The signal broadcast by the antenna 29 is preferably monitored at the stati~n 11 by means of tuner/decoder 31. The tuner/decoder 31 receives the broadcast signal from the antenna 29 and monitors the video signal to detect and decode the identification codes recorded by tha encoder 23. The , identities of the'encoded programs and the time and duration of their transmission is stored by the tuner/decoder far transmission to a'remot~ host computer.
In some installations, the station is not well located for receiving the'broadcast signal from the antenna 29. In such instance, a tuner/decoder 33 may be connected to a tap on the antenna 29 o detect and decode the broadcast signal.
Referring now to Fig. 2 of the drawings, there is illustrated a mire detailed block diagram of the illustrated ~~enebodiment .ofr~=the'~encos~er system 23 of the > -invehti~n: ~- The encoder'':system~~.23 -~~.ncludes'' a 386 type personal computer or similar machine 35 preferably having at least 4-megs: of internal'memory and a solid state disk drive: The encoder 37 nday take the forrnn of a circuit board installed in an expansion s~:otof the computer 35. A 9600 baud modem 39 is also connected to the'computer 35, preferably as another expansion sl~t board. The modem 39 connects the computer 35 to the host computer.

!W~ 93/'p6~ P~T/~JS92110062 ~firi, ~~~;~ , 12 ..
The encoder 3? has an input terminal connected to P
the video output of the input tape drive 19 (Fig.i) and an output terminal connecting the encoded video to the output -video tape cartridge drive 21. Optionally, for the benefit of the dubbing operator, the encoded video signal--may also be connected to a video monitor 41 which includes a character generator, for displaying both the video signal of the program being encoded and the alph~t'numeric display of the characters being encoded on the selected line.
Referring now of Fig. 3 of the drawings, there is shown a schematic diagram of the encoder 37. The video signal from the input video tape drive 19 (Fig. 1) is connected to the input of the amplifier 43 through the video input terminal 45. The output, of the amplifier 43 is connected to the input of a gain control amplifier 4? and to a sync strip circuit 49.
Sync'strig circuit 49 detects the presence of the vertical and horizontal sync pules on the input video and develops outputs coincident in time with the presence of such signals on the :. input, : The .: circuit : 49 also ,~ develops : other outguts temporally 2~-coincident with,-the location of,;the, color burst .and :back-.
porch. In the illustrated embodiment the sync strip circuit 49 is implemented by a NS 1881 semiconductor chip available from National Semiconductor Co. The sync strip circuit 49 also develops an output-which indicates whether the odd or even field of each frame_is present at the input 45. The outputs of the circuit 49 corresponding to the vertical sync, horizontal sync and color burst and back porch are connected to the line detect circuit 51. An output of the lane detect W~ 93/1063Q PC1'/US92/1OQ62 21239~~
circuit 51 is connected to the normally open grounding switch circuit 53 for selectively grounding the output of the amplifier 43 during the color burst and back porch. signals.
The encoder 37 is connected directly to the bus of the computer 35 (Fig. 2) by the bus logic 53.-°-The output of the bus logic 53 is connected to a series of registers which include the scan line register 55, the preamble register 57, two code byte registers and 59 and 61, each of which.are 11, bytes long, and a cantrol register 63. The scan line register 55 stores the number of the line in the video scan which is to be encoded by the encoder board 37 with the identification code in accordance with the invention. Preferably a line between numbers 10 arad 20 is selected by the scan line register 55 for encoding under the control of the computer 35.
15' The preamble register 57 stores a one byte preamble code. The code byte registers 59 end 61 are each used to store a 10 byte identification c~de and a one byte cyclic redundancy check code. The preamble identification code and cyclic redundancy -t-a'fcheck"vbyte are received r~from he~:: computer: 35 is r,the : ~PC bus logic 53 for-each program'. to be-encoded.rt. .The control register 63 acts under the control of the'computer 35 to enable the enc~der board 37 to begin encoding he selected line of the video input signal:
The output of the scan line register 55 is connected 'to the line detect circuit 51. The output of the preamble register 57 is connected to the one byte code shift register 65. The outputs of the code byte registers 59 and 61 are also connected to the code shift register 65 through tlhe odd/even x,;,,:::. . . , , .
W~ 93!1~630 PGT/US92/10062 select circuit 67. The odd/even output of the sync strip circuit 49 is connected to the odd/even detect circuit 67 to control the selection of which of the two code byte registers -59 and 61 is coupled to the code shift register 65 at.any time. An output of the line detect circuit 51~°is connected to counter 66 to enable the counter to count clock pulses from the phase lock loop c~.oek 68. The output from the counter 66 is c~nnected to the code shift register.65 for enabling it ~.t the appropriate time. The horizontal sync pulse output from 1~ the sync strip circuit 49 is connected to the clock 68 for phase locking the clock 68 to the horizontal sync pulses which define the video scan line timing. The phase lock loop clock 68 divides the scan line into 128 bit times between successive horizontal sync.pulsesPreferably the clock 68 includes a 12 Mhz clock oscillator whose frec~uencyvis divided to provide a very stable 2M hz output to the counter 66 and to the code shift':register 65 for controlling their operation. The~code shift register 65 includes a framing bit generator 70 for generating a one-.:l~it.~:~framing pulse to mark the beginning of 2~ ..: ~~ :the coding. data for.--ahe scan -line being encoded.
The output of the level controlling amplifier 47 is connected to the input of an. amplifier 69 through a normally closed series switch 71. 'The series switch 71 is controlled by a control output from the line-detect circuit 51. The shift register 65 has a serial code output which is connected o control the operation~of a bi-level switching circuit 73 which develops an output of either 5 volts or ground depending upon the lave? of its input from the code shift register 65.

wo ~~,go63o 212 3 9 9 ~ "0062 - . 15 The output of the switching circuit 73 is connected to the input of a level setting amplifier 75 whose output is connected to the input of the amplifier 69 through.a normally open switch 77. The control output of the line detect circuit 5l is also connected through an inverter 79 to~"control the operation of~the switch ?7 in order to selectively connect the level setting amplifier 75 to the input of amplifier 69. The switch 82, which is held open by the Vee supply voltage, is , connected between the input terminal 45 and the output terminal 81. Switch 82 closes when the V~B supply voltage is removed from the encoder'37 for bypassing the encoder 37 in such event.
In the preferred'embodiment, the encoded scan line data consists of the framing bit followed by 96 bits of data.
Each bit is either 1, represearted by a 70 IRE voltage level or a 0, represented by a 0 IRE voltage level. In normal television practice, the voltage excursion of the video signal is'arbitra~ily divided into 100 levels with 100 IRE
~n:v:'cdrresgondinqrto--the-brightest white and 0 IRE corresponding ~dr- ~-to; pure-~hlack: .The 7~ IItE used in -the :'illustrated embodiment of the present invention to represent a binary 1 gives adequate differentiation from the 0 IRE level representing a binary O for easy detection while not risking overdriving the video circuitry.
The framing bit, Which is always a binary 1, follows the horizontal sy~ac pulse on the encoded scan line. The ' framing bit is recognized by the decoding circuitry as the beginning of an encoded scan line and initiates the decoding WO X3110630 PGTlUS92110062 ,_.: .

of the line. Following the framing bit is a one byte preamble code which, in the illustrated embodiment, is a two digit hexadecimal number which can be used to specify the significance of the data bytes on the remainder of the line as, for instance, identifying a particular commercial or syndicated program. Following the preamble code are ten bytes of data which identify the,'encoded program. A one byte cyclic redundancy check or error code follows the 10 data bytes. For commercials, the 1~ data bytes are the 8 bytes international standard commercial identification ("ISCI'°) code which uniquely identifies the encoded commercial, followed by two bytes used to identify the advertising agency or provide other information. The first four bits of the ISCI code are capital alpha.letfiers and ,the following four bytes are numbers. .
15- It is preferred in the illustrated embodiment of the invention to encode both fields of each frame of the video information of the encoded program pith the identification codes It'is possible, however, to enc~de only the odd or even :a,~: :fgeld of each :frame,.. or .ao encode the two fields. .of each frame :-:_~. differently... ==wIf the two fields are enc~ded diffexently,-:~..then .:::
each frame could be encoded with 20 data bytes. It would also be possible to encode one field of each frame with the program identification and to use the second field as a counter: such an arrangement is useful in cases such as that in which a co~oamercial is embedded in ~ syndicated program and the broadcast station is contractually obligated to run the commercial even if the syndicated program is not. In such event it would be possible to identify such commercial based ,, .,:.: , ..~ . . .
WO 93!10G30 PGT/US92/10062 r ~12399~
1~ -on the detection of the identification code of the syndicated program and the location within the program determined by the counter. If only a single field of each frame were encoded, it would also be possible to use the other field for different information, thereby permitting more efficient-use of the scan line. The one byte preamble identifies which of the various possible encoding schemes is being used for a particular program.
In operation, the input video signa3 from the input video tape recorder l9 (Fig. 1) is amplified by the amplifier 43, level adjusted by the amplifier 47 and connected to the video output 81 through the a~ormally closed switch ?1 and the amplifier 69: The sync strip circuit 49 senses the output of the amplifier 43 and develops separate outputs in time correspondence to the presence of vertical sync pulses,. the horizontal sync pulses, and the'color burst and back porch signals o~ the video at he output of amplifier 43. The line detect circuit 5l receives the horizontal sync, vertical sync, and - color -burst outputs .from 'the 'sync ~ "strip circuit 49 and : - ' :r counter='the number ~f horizontal sync ': sic_~als occurring after each vertical sync in order to count the lines of the video field as they are present at-the output of the amplifier 43.
The line detect circuit 51 compares the field line determined from the vertical and horizontal sync inputs with the scan line number stored in the scan line register 55 to determine when the video scan line to be encoded is present at the ~utput of the amplifier 43.

V6~0 93!10630 PGT/US9Z/10062 ,t".,,.

- The line detect circuit 51 is enabled upon the sensing of the horizontal sync signal of the scan line from the sync strip circuit 49 to be encoded such that the trailing edge of the horizontal sync pulse causes the line detect circuit 51 to close the normally open switch 5~3w'until the trailing edge of the back.p~rch output pulse from the sync strip circuit 49, at wh.iCh time the switch 53 is opened again.
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The closing of the s~ii~ch 53 grounds the output of the , amplifier 43, thereby bloc%ing the transmission of the 3.6 Mhz color burst signal which otherwise would generate noise on the encoded signal. The end of the back gorch of the line to be encoded also causes the output of the line detect circuit 51 connected to the switch 71 to go high for the remainder of the scan line. This.op~ns switch 71 and closes switch 77 for the remainder of the scan line, thereby disconnecting the amplifiers 43 and 4? from the video output 82 and connecting the code switch circuit 73 to the video output 81 through the ~plifiers 75 and Sg, , ;At - he wsame~<time as .: it closes the bewitch 53 and .. opensv he-v-switch 71, ~ the line detect circuit -51 generates the Start Code signal for initiating the encoding of the remainder of therscan line. Since the.phase lock loop clock 68 divides the scan line into 128 bit spaces and the information to be encoded onto the line occupies only 97 bit spaces, there is ' some e~ctra room on the scan line. In order to allow for possible phase shift resulting, for instance, from time base corrections performed by the television broadcast station, it is preferred to position the information encoded on the scan ~Y(? 93/10630 PC1'/US92/10062 2~ 239 line roughly in the middle of the available space. This objective is accomplished on the illustrated embodiment of the invention by using the counter 66 to delay the beginning of the encoded portion of the scan line so that approximately ecnaal space exists between the beginning and end" of the encoded data and the preceding and following and horizontal sync pulses, respectively:
The Start Code signal generated by the line detect, circuit 51 enables the counter 66 to begin counting bit time defining clock pulses'from the clock 68. In the preferred embodiment, the counter 66 generates an output to the code shift register 70 after counting 32 clock pulses, thereby defining a 4 byte wride space between the point where the switch ?1 is open and'switch 7? closed and the beginning of the encoding:.
phce it is enabled by'the output of the counter 66, the code shift register 65 begins serially transmitting code data bits, one for each clock cycle of the clock 68, to the -control in~aut 72 of -.the :switching : circuit 73. At the (first ZO clock cycleafter the' c~unter 66 -has 'been enabled, the framing '~-bit,generator ?o causes a binary 1 to be transmitted to the switching circuit ?3.
At the beginning of each field the code shift register 65 is initially loaded with the contents of the preamble register 57. During the second through ninth clock pulses received from the clock 68 after being enabled by the counter 66, the code shift register 65 serially transmits the preamble code to the switching circuit 73. Thereafter, WCl 93/10630 PGT/US92/10062 ~~.~3995 depending on whether the odd or even field is present at the video input terminal 45, the oddjeven select circuit 67 controls the transfer of code bytes from either code byte register 59 or 61 to the code shift register 65. The bytes 5 are shifted from the code byte registers 5~ or ~61 one byte at a time in parallel. The bits of the first code byte are shifted out of the code~shift register 65 during the 10th through 17th clock py7:~es received by the code shift registex 65 from the clock 68 after being enabled by the counter 66.
10 This process of transferring the code bytes one at a,time to the shift register 65 arid then serially transmitting those bits to control the switching circuit 73 continues until all ten code bytes and-the cyclic redundancy check byte have been transmitted.
15 For each binary 1 bit transmitted by the code shift register 65, the control input 72 of the switching circuit 73 is high for the entire bit time. This causes the switching circuit 73 to connect its output to the five volt supply.
wWhen a ~ero.bit~is aransmitted from the code shift register 65 20 v.-,,. the control ;.input 72 : is held low for: he entire bit period, which in turn causes the output of the switching circuit 73 to be connected to ground. The .amplifier 75 is adjusted such that when its input is at five volts, its output is at 70 IRE.
When its input is grounded, the output is at 0 IRE. The output of the amplifier 75 is connected to the video output 81 of ~e encoder 3T through the amplifier 69. Thus, the data front the code shift register 65 is transmitted as a binary bit a~c.,~ ~..~. ~ . . - . - ..~... , ... .., w~ ~3e~o~3o rcrivs~2eioo~2 .. 21 stream to the video output 81 of the encoder 37 in which a 1 is a ?0 IRE level and a 0 is a 0 IRE level.
Referring now to Figs. 1 and 4 of the drawings, some television broadcast stations do not use a dubbing computer to control the dubbing ~f the video tape onto a video tape cartridge. Yn shch stations, the alternative encoding system 23° may be used to encode television programs in accordance with the invention: The encoding system 23 is.substantially, identical to the encoding system 23 illustrated in Figs. 1 and 2 of the drawings: In the case of the embodi~aent of Fig. 4, however, the functions of the dubbing computer 1? are taken over by the computer ~ihich forms part of the encoding system 23'. In this alternative system the information concerning the programs to be encoded is entered into the computer of the '15 encoding system 23' by means of either of floppy disk drive.83 or the keyboard 85: Display ~7 is connected to the computer in the encoder systemv23° for use by the dubbing operator: A
label printer 89 is connected to the computer in the encoder systemr.~3 °. vfor~::preparing -labels : identifying the contents' of '20 the video':cartridges',being~recorded at- he vide~'cartridge drive 29..
In certain stations it is necessary to enter video tape queuing codes at the beginning of the tape in the video tape cartridge in order to give the station master control 25 board operator queuing information that confirms that the correct cartridge is loaded prior to airing:.
In such installations,'an output 9I from the computer in the encoder 23° is connected to the output video ~yQ 93/~~30 PZ.'I'1US9211Q~62 22 _.
;.
cartridge recorder 21' for sending video tape cuing codes to the cartridge recorder for being recorded on the initial portion of the tape in the cartridge.
Referring now to Fig. 3 of the drawings, there is illustrated a block diagram of the decoder system 93 in the tuner/decoder 31 or 33 (Fig. 1). The decoder system 93 is similar in basic configuration to the encoder system 37 (Fig.
2). It includes a 386w'level personal computer 95 preferably having at least 4 Megs. of internal random access memory and a solid state disk 96. The decoder board 97 is preferably configured to be plugged into one of the expansion slots of the computer 95. A 9600 baud modem 99 is also preferably connected in one ~f the expansion slots of the computer 95.
The decoder system 93 receives the video input signal from the tuner/decoder system 31 or 33 and monitors all video scan lines:-between lines 10'and 50 of each field of the video signal. When the decoder system 93 sees one such line encoded in accordance with the encoding arrangement of the illustrated --.embodiment of: the invention, ~ ~it separates the data .on :.the . .
encoded;:scan line from the composite video signal :and w -, assembles the scan line data records for each encoded program detected. Such records are stored in the solid state disk drive 96 in a database managed by the computer 95. These records also include data specifying the time at which the program commenced and the duration of the program in terms of the number of consecutive fields on which the data is encoded.
The record for each encoded program detector also preferably includes the number of the encoded line and a quality index i~VO 93110630 PCTlUS92110062 - 2~2~99~
23 ' for the encoded video signal. These record are stored on the solid state disk 96 under control of a database management system for later retrieval by the host computer through the modem 99. In accordance with the invention, the stored data is preferably retrieved from both the encoder~system 23 and the decoder system 93 on a daily basis by the host computer which is normally at a remote site. The data from a particular station-may be combined with similar data from , other stations in the same or other markets to create an occurrence database of programs which are run locally and nationally:
The data from the decoder system 93 is also sent to the traffic computer l3, pgeferably by a local area network, for use by the station-traffic department in correlating the ~5 programs and commercials actually transmitted with contracts for billing and monitoring purposes.
The quality index-is determined by a programmable algorithm according to which the failure to find a encoded t«<:; - liner: an.:,a~-preselected number<= of consecutive: frames, -.
typically set at about 60, or the absence-of colorrburst results'in a w reduced quality index If the identification code is missing .
from adore than the preselected number of consecutive frames, the encoded video following the break is treated as a separate pxogram:
It is also possible to perform an audio check, for instance by c~mparing a fast fourier transform signature of the received audio s~.gnal with that of the original program.

1,V0 93/10630 PCT/U592/10062 ~<,:.,, The decoder system 93 can also receive and store the as-aired log from the station control console computer by monitoring the output of the control console computer to an as-aired printer which printer prepares reports of the as-aired log. The as-aired log may be later retrieved via the modem 99 by the hostwcomputer. The as-aired log allows automatic testing of occurrences of commercials and programs against the decoder occurrences recorded. This testing at the host computer assures accuracy of the database information and eliminates problems with last minute changes in commercial schedules that do not always get recorded at the control c~nsole computer. The availability of the as-aired log information also allows greater differentiation of the source of a common commercial use by both local, regional and national advertising agencies.
The information at the host computer is combined with information from other databases and various statistical reports are compiled for use by the broadcast stations, advertisers:and-advertising agencies either-by hardcopy or,on-Z~ line access to the..: host ,~omptter:. . .
Referring now to Fig. 6 of the drawings, there is illustrated a schematic diagram of the decoder 9? of the illustrated embodiment Qf the invention. The decoder 97 consists of a coa~trol portion made up of the I/O CPU 101 and Z5 associated registers and memory, and a tuner/decoder section made up of the tuner 103 and the associated decoding circuitry which receives the television signal broadcast by the transmitting station, determines the presence of a scan line WO 93!10630 PGTJUS92l10862 2~23~9~
encoded in accordance with the illustrated embodiment of the .
invention and decodes the information present on the scan line. An 8 bit data bus !p5 interconnects the various circuits on the decoder board 9? and acts as the communication 5 Bath among them. Communication between the decrider 97 and the computer 95 of the decoder system 93 (Fig. 5) takes place via the universal asyncronous receive and transmit circuit ("UART") 107.
When power is turned on, the reset circuit 109 10 generates a power-up signal which resets the various circuits on the decoder 97 to'an initial condition. The power-up s~.gnal causes the I/0 CPU 101 to go to the "boot mode".in which it is able to communicate with the computer 95 through the UART 10?, but is otherwise waiting. The I/O CPU 101 15 receives instructions from and transmit data to the computer 95 through the data register 111 and the data bus 105 on an 8 bit wide path. The BK ROM 113 stores code for interpreting .the commands received from the computer 95 when the I/O CPU
101 is in the boot mode . ~ ;- The boat , mode commands received ~ from 20 the.c~mputer-95vcausevthe:I/O CPU 101 to address the-locations.
in the ROM 113 which store the microcode needed to interpret and execute each c~mmand. The'I/O CPU 101 addresses the ROM
113, the 32K EEPROM 115 and the 64K SRAM 116 through tlhe address register 118. Since the addressing of these memories 25 requires 16 bits, two 8 bit bytes are sent by the I/O CPU to the address register 116:
The boot mode commands include a "Send Status"
command which causes the I/O CPU 101 to tell the computer 95 W~ 93/1Q630 PCT/US92110062 ,< , IP
whether it is in the boot or operational mode. The Go Operational" command causes the I/O CPU 101 to switch from the boot mode to the operational mode.
The UART 107 is connected to the computer 95 through an RS 23B interface and serially transmits or xeceives data one byte at a time to or from the computer 95. Information is sent by the I/O CPU-~~:2.01 to the computes 95 one byte at a time 1.~ , in response to tl~e~~receipt from the computer 95 of "clear to' send" signal on the CTS line to the UART 107. The receipt of the GTS signal causes the UART 107 to generate a first level interrupt to the I/O'CPU 101 which in turn causes the I/O CPU
101 to address the SRAM 116 to send the next data byte to the computer 95 through UART 107. This mode of operation permits the computer 95 to handle other matters when it needs to without risk of comgromising the integrity of the data which is being gent to it by the I/O CPU 101.
~~n the I/O-CPU 101 enters the operational made, it shifts o the EEPROM 115 to interpret commands received from .~ .:~-=the:~..eomputer«95..:and sends the channel- number received from the ~ - con~put~r:.~.95 ,.as part° of the Go Qperational command ~to the ~-.::
channel register 11? through the data register 111 and bus 105. The Go Operational command also includes a filter byte which programmatically contrals I/O CPU 101 on the criteria fc~r recognizing the reception of encoded ffields as the beginning of an encoded program, and for determining whether a series of encoded fields represents one or more programs. The first-two bits of the filter byte determine how many successive encoded fields must be found before the I/O CPU 101 _ 27 ~~~~JJS
determines that an encoded program is being received. These -bits are normally set such that two successive encoded fields (one frame) are required before the beginning of a program is recognized, but if the station is particularly noisy, the filter byte can specify a larger number, eg. fouCr fields (two frames), which must be found before the beginning of a program is recognized. The system time stamps the start of the program based on the first encoded field bitt must recognize , the required number of successive encoded fields before the reception pf an encoded program is confirmed. The ather six bits of the filter byte are used to set the number of dropped fields which can occur before the information following the dropped fields is considered to be a different program.
Typically, these bits are set to specify 180 fields (3 seconds) but different numbers of fields can be set as desired. If the filter bats are set at 180 fields, and the dropping of 180 or fewer fields occurs, the encoded segments before and after the dropped fields are considered to be a --single.'program but thequality index~is decreased:r This of cou~cse assumes- :that' thefields before sand -after =the gape are .
encoded with the'same codes. If more than 180 fields are dropped in succession, the twovencoded segmenfis proceeding and -following the dropped fields are considered to be two separate p~.~~ran~s The output of the channel register 11'? is connected to'tuner CPU 119 which controls the tuner 1~3. The channel number is stored in the channel memory portion of the tuner CPIJ 119 where it is used to tune the tuner 103 to the proper dN~ 93/10630 PC1'lUS92/1OQ62 ?~,~~ frequency. In the event that the station to which the tuner 103 is tuned goes off the air, the Video Lost input to the tuner CPU 119 is set. In response to this signal, the tuner CPt1 119 causes the tuner 103 to scan back and forth over a 2 megahertz band centered on the channel frequency'in order to vfind the video signal:'~~as soon as it comes back on. Scanning ., ~ :.., over a 2 megahertz band enables the system to be used with cable stations which may be transmitting a particular channel.
on any one of three different frequencies within a 2 megahertz ~ 10 band about a nominal center frequency; depending upon the particular cable network arrangement. In a broadcast station, narrower scanning bands could be used because the station frequency never varies more than about 10 kilohertz from the nominal Channel frequency.
The video ~utput of the tuner 103 is connected to a sync strip circuit 121 which may be identical to the sync strip'circuit 49 of the encoder 3? (Fig. 3). The sync strip circuit 121 senses the vertical sync and the horizontal sync ycaulses on ; he ; video iaaput -: and .generates output pulses at : times ~o~.the~.vertical~-and:horizontal sync pulses and of the back .
porch for use in the decoding operation: The sync strip carcuit 12l also generates an.output specifying whether the odd or even field is present. The horizontal sync output is connected to a filter 123 which generates a squared stable ' ~~ 25 horizontal. sync output for use by the line parser circuit 133.
The video output from the tuner 103 is also connected through the amplifier 125 to the sample and hold DC
restore circuit 127. The back porch output of the sync strip wo s~iao~~o Pc.-rius~zsaoosz circuit 121 is also connected to the sample and hold circuit 127 to cause it to sample the voltage level of the video signal at the output of amplifier 125 at back porch time and hold that level until the back porch of the next video line in order to provide a DC reference level for decoding the information on the video signal. The DC level in the decoder 97 of the received video signals can float over a relatively wide voltage range. The sample and hold circuit 127 provides a reference equal to the back porch voltage level, which is substantially O IRE.
The phase lock loop video clock 129 may be similar to the clock 68 in-the encoder circuit (Fig. 3). The clock 129 generates a 2 l~z output which is phase locked to the H
.sync output of the sync strip circuit 121 in order to divide '15 the video line into 128 bit times from H sync to H sync.. The output of the video clock'129 is connected to the counter 131 which is in turn connected to the line parser: circuit 133.
The counter 131 counts the 128 clock guises on each video lane and is:reset°~at:.the:~end.of each line. The line parser:133 ~ also receivesv~the vvideo"' output from ' the amplifier : :125 c ~~-:: The lure parser 133 monitors each video line to determine whether tY~e'various portipns ~f the line are present and in the appropriate time slots. It develops outputs for the H sync, the eolor burst and the back porch which are high if those portions of the video line are present and in the appropriate tine slots as determined by the Gaunter 131, and are low if they are not present or are not in the appropriate time slot.
The 'V bit valid output of the line parser 133 is high during the period that valid data bits can be present on the encoded scan line. This occurs from the end of the back porch time until close to the end of the scan line.
The timing generator circuit 135 receives a 12 Mhz output from the video clock and the V sync and H sync pulse outputs from~the sync strip circuit 121, and generates a plurality of timing pulses for controlling the timing of various parts of the°~~decoder 97. One such output is a , sampling pulse which is generated at the middle of each of the 13 bit time periods after porch time for lines 10 through 50 of each field. This sampling pulse output is connected to the line parser 133 and causes it to sample the video level at the center of each such bit time period to look for the framing bit. i~lhen the line parser 133 sees a high video voltage level at the sampling time, it sets its sync bit output high, tentatively indicating that a framing bit is present.
The video output of the amplifier 125 is also connected to'an input of the video bit comQaritor 137, the H
sync:..compa=itor 139 and,_the colorburst:~detector 141. The : outputs_. of.v the DC restore circuit :x127 is . connected to the other;
inputs of the comparitors 137 and 139. The output of the H
sync compaxitor 139 is'connected to the line counter circuit 143:' The output of the video bit comparitor 137 is connected to ths: shift register 145 and to the cyclic redundancy check circuit 147.
A serration detector included in the timing geherator circuits'135 generates an output, referred to as "barge Kick", during the serration time. The serrations are ' . . ... '~W Yv -- v VN~ 93/10630 PC~'/tJS92/101062 rtn.'1~
~ 2~2399~

the H sync pulses that occur during the first 10 lines in the vertical blanking interval. They are more closely spaced in time than the H sync pulses for the other scan lines and the first five of them are positive going. The beginning of the serration time is contemporaneous with the V sync pulse. The serration detector recognizes the serrations by the fact that the counter 131 does not get close to-the 128 count between adjacent H sync pulses. The Large Kick signal disables the , phase lock loop in the clock 129 and the line parser circuit 133 and resets the line counter 143 to 10: At the end of the serration, the phase lock loop and the line parser circuit 133 are once again enabled and the line counter 143 begins counting H sync pulses starting with line 11. The competitor 139 is able to recognize H sync pulses by virtue of the fact that they are the only negative going pulses.
The sync bit output from the line parser 133 is connected to, the shift register 145 far enabling the shift register 145 to begin shifting in the code bits which immediately follow the framing bit in successive belt 'times.--° To confii~n~ that tD~e fuming: bit detected by the' line parser 133 is-actually the first bit of an encoded line and not just ordinary video, the decoder 9-7 compares the first byte following the frayaing bit with the preselected preamble codes stored in the preamble memory 148 to determine whether a valid preamble is present. The competitor 149 is connected to the first bit location in the shift register 145. ~uring the first bit time following the sync pulse from the line parser 133, the competitor 149 compares the first video bit with the W~ 93!10630 PCT/US92/10062 ,...., ' first bits of the preambles stored in the memory 148 and eliminates the stored preambles which do not match. Dotting subsequent bit times the competitor 149 compares the successive bits in the first location in the shift register 145 with the corresponding successive bits of remaining matching stored preambles until all stored preambles are eliminated or a match ss~.~~found. If no match is found, the line is considered to~~be ordinary video and the shift register 145 is disabled. Tn such event the line parser 133 continues x0 to look at subsequent lines seeking to find another potential framing bit.
v If a match is found, the preamble byte stared in the shift register 145' is transferred in parallel into the first register of the Video Data FIFO 151. the Video Data FIFO 151 contains a 16 eight-bit registers and may be implemented as an AM 29525 integrated circuit which is manufactured by AMI Inc.
Only 13 of the 16 registers are used in the illustrated embodiment to store the information from the encoded line and the - mxmber . of; the . rencaded l ine : ..
r.The 10 identifying eight-bit bytes and the CRC byte on the enc~ded line of the received program are then serially shifted into the'shift register 145 through the video bit competitor 137. When each eight-bit byte is shafted into the register 145, it is transferred in parallel into the next available register of the Data FIFO 151 until all 10 infaxmation bytes and the CRC byte are resident in the 'registers of the FIFO 151.

W~ 93/1063(D PCT/US~Z/10062 ._.,, 2I23~95 The sync bit from the line parser 133 also enables the cyclic redundancy check circuit 147 to begin receiving the video bits of the encoded line. At the end of the 12th byte of the encoded line, which corresponds to the end of the cyc~.ic redundancy byte, the output of the cyclic redundancy check circuit 147 is zero if the data on the encoded line is correct. If an error has occurred, the outgut of the cyclic redundancy check circuit 147 is other than zero at the end of the last bit time of the encoded CRC byte.
When the iTideo Data FIFO 151 transfers the CRC byte from the shift register to the 12th register of the FIFO 151, it also disables the shift register 145, stops the reading of video bats by the cyclic redundancy check circuit 147, and loads the contents of the dine counter 143 into the 13th FIFO
register: The FIFO 151 then enables the cyclic redundancy check circuit 147 such that, if its output is zero, it generates a level zero interrupt (referred to as FIFO RDY) to the I/0 CPU 101. Ln.response, the I/O CPtT 101 causes the contents of:~ahe FTFOr-151 to be traa~sferred to the' SRAM 116 via . : . w. the ~ data vl~us '-105 .~ Thus, he SRAM 116 v° receives the information recorded on the selected scan line of the encoded television program along with the number of the line on which it was encoded:
In the event that the output of the cyclic redundancy check circuit 147 is not zero at the end of the receipt of the encoded line, the data stored in the FIFO 151 is not transferred to the SRAM 116 but is discarded. If this WO 93!10630 PCT/US92l10062 ;f",''3 t '~99~a . 34 - happens at a field of an encoded program, it is treated as a dropped field for purposes of the quality index calculation.
Tf the contents of the line counter 143 reaches 50 without any encoded line having been found, it ceases counting and disables the shift register 145. In such case the field being received is assumed not be encoded.
The encoded line data received by the SRAM 116 is compiled by the I/0 CPU 101 into a series of records,. one fob each encoded program decoded by the decoder 97. Each such record contains the identification data for the encoded program, the start time and tha duration of the program in terms of the number of encoded fields which it contains and the quality index for th~.program.
Periodically,the computer 95 commands the decoder 97 to send to the host the information stored concerning the encoded programs which'have ~~en monitored by the decoder 97.
The computer 95 sends to the IjO CPU 101 the °'Read Status"
comimarad which causes,theI/O CPU lOl,to send back a status ,: byte: ~ The : first..bit .of the status byte specifies that tlye I/o -.~-vCPU~~101 isvin the operational mode:~.The ~e~~nd bit,<referred to as the '~peneling" bit, tells whether or not there is at least one,complete program which has been monitored and the record of it stored in the SRAM 116. The third bit of the status bytespecifies whether the I/O CPU 101 is currently decoding a program: If the pending bit is set, the computer 95 can command the I/O CPU 101 to send the pending records from the SRAM 115 to the computer 95 starting with the earliest record.

... ; : '.. ,..'., .;- .. ,.;
;' . . . ..
VY~ 93/10630 _ ~ ~ 2 ~ ~ 9 ~ S92/10062 The SRAM 116 is programmatically organized in a series of successive registers, each capable of storing the record of one monitored program. Addresses for the registers in the SRAM 116 are arranged in a ring, such that if the 5 address of the highest numbered register is incremented, the address becomes that of the lowest numbered register. The I/O
CPU 101 maintains in one memory location the address of the register in SRAM 116 containing the next pending record to be sent to the computer 95. A second location stores the address 10 in the SRAM 116 of the register in which the record of a program presently being decoded is being compiled, or if no program is being decoded, the address of the next available register-in SRAM 116 in'which a new encoded program record can be stored.
15 When the computer 95 instructs the I/O CPU 101 to send thepending records of completed decoded programs to it, the I/O CPU 101 successively sends the pending records via the :DART 107 to the computer 95, incrementing the address of the :.register for each-successive pending record,''until the address 20 of~:~the iregister storing the next pending record becomes equal to the address in the second location of the register where the record of the next program to be decoded is to be stored.
This condition occurs when the registers in SRAM 116 are ~mptyo 25 When, during reception of successive encoded programs, the address in the second location becomes equal to that of the pending record in stored the first location, the SRAM 116 is fu114 If additional programs axe decoded when the yV0 93/10630 PCI'1US92/10462 .-36 _ '~~~ registers in the SRAM 116 are full, the data for the newly received programs is discarded. The SRAM 116 can store the records of up to 1440 programs in its registers, which corresponds to two full days of 15 second encoded programs.
Since the computer 95 normally retrieves the records of'the decoded~programs from the decoder 9? at least once per day, the problem of the re~g~sters of the SRAM 116 becoming full nonaally does not occur.
The decoder 97 is also capable of decoding base band video signals at the station, If the channel number sent to the channel register 117 by the I/O CPU 101 calls for channel 0, the tuner CPU 119 shuts off~the tuner 103 and the base band vide~ is received st terminal 153. The received base band video is conrae~ted to the sync strip circuit 121 and the amplifier 1.25, and it is thereafter treated in the same manner as video signals received by the tuner 103.
The status register 155 is an 8 bit register which can be read by the I/O CPU 101 thereby allowing the I/O CPU to w.:' monitor the operation'of important components of. the decoder 9? ., : . The ~-3 0 , --6 and +~9 .volt : suppl ies are generated on the decoder board by the regulator 154. The porch signal is received from sync strip circuit 121.' The color burst time signal from the line parser 133 and the color burst pulse on the output of the detection circuit 141 are connected to an AND gate (not shown) whose output is connected to the burst valid input of the status register 155.. The odd/even output of the sync strip circuit 121 is connected to the odd/even input of the status register 155. The contents of the status V1~0 93!10b30 PCTlL1S92/10062 212399.
register 155 are polled by the SRAM 116 frequently during operation of the decoder 97.
In embodiments of the invention where only one field per frame is encoded, the odd/even output of the sync strip circuit 121 can be used to enable the line counter 143 and shift register 245 only during the odd or even field as appropriate. In systems where the odd and even fields are encoded differently, the odd/even output of the sync strip circuit 121 can also be used to differentiate between the two fields .
H7hile the illustrated embodiment of the invention has been.described in connection with programs recorded on video tape and dubbed'onto video tape cartridges, it is apparent that other media could be used for storing the programs both before and after encoding. For instance, a video disk, particularly those with a read/write capability could'be used as the program storing medium: As used herein, the references to video tape or video tape cartridges are intended to apply equally to other such media whether now in use or int-roduced in.th~ future.
The'system of the present invention.has many advantages over those proposed in the prior art. The fact that it is an in-station system in which the encoding, and preferably both the encoding and decoding is performed locally ~t the station permits the particular line to be encoded to be selected so as not t~ interfere with other operations of the station and to avoid problems with stripping. It is possible also to use the system to monitor programs broadcast by a iV0 93/10630 PCT/US92/10062 ',..", _ . 38 station which programs have been encoded at the originating network or syndicator. The system of the invention can easily distinguish between such sources by, for instance, having different sources encode different lines of the video signal or by the use of appropriate preamble codes for~'~different types of sources.
a

Claims (27)

CLAIMS:

1. An in-station system for automatically encoding and monitoring the transmission of television programs at a television station, said station having a video library management system, comprising, at the station:
an input video player for playing a recorded storage medium containing a program received at the station;
an encoder coupled to the output of said video player for encoding the video information signal of said received program with identifying data;
a video recorder coupled to said encoder for recording said encoded program onto a video storage medium compatible with the station's video library management system;
database means for storing information concerning the recorded encoded programs;
a tuner/decoder for receiving the programs transmitted by such station and for detecting the presence of such identifying data on the video information signal of said received programs; and means for storing information concerning the identity and transmission of encoded programs in said database means.

2. The in-station system of claim 1 wherein said encoder includes means for selecting a line in the overscan region of the video information signal for encoding with such identifying data.

3. The in-station system of claim 2 wherein said selected line is between lines 10 and 20 of the video signal.

4. The in-station system of claim 2 wherein said preselected line is in the vertical blanking interval.

5. The in-station system of claim 2 wherein said decoder includes means for locating such identifying data on a scan line occurring between predetermined scan lines of the composite video information signal of said received programs.

6. The in-station system of claim 1 wherein said decoder includes means for determining and storing a quality index indicative of the quality of the received video signal of such encoded programs.

7. The in-station system of claim 6 wherein said decoder includes means responsive to the absence of encoded information on up to a predetermined number of consecutive fields of an encoded program for reducing the quality index associated with such encoded program.

8. In a system for automatically monitoring and verifying the transmission of television programs by a television station having a video library management system, an in-station method of encoding such programs comprising the steps performed at the station of:
receiving programs to be broadcast by such station;
dubbing such received programs onto a storage medium compatible with such video library management system;

encoding the video portion of such received programs with an identifying code simultaneously with the dubbing of such program onto said medium; and storing information concerning said dubbed encoded programs in database means at the station.

9. In the system of claim 8, the method for verifying the transmission of such encoded programs by such station comprising:
receiving at the station the video portion of the encoded programs being transmitted by said station;
detecting and decoding at the station the identifying code encoded on the video portion of such received encoded programs;
storing information concerning the identity and transmission of the encoded programs in said database means for transmission to a host computer.

10. The method of claim 9 wherein said receiving, detecting and decoding of the encoded programs is performed at the transmitting station.

11. The method of claim 9 wherein said station is a broadcast station and wherein the receiving of the video portion of the encoded programs is performed by monitoring the signal broadcast by said station at a tap at the broadcast antenna of said station.

12. The method of claim 8 wherein the information encoded on said preselected line is the same on both fields of the frame of the video portion of the encoded program.

13. The method of claim 8 wherein said identifying code is encoded on a selected line in the overscan portion of the video information signal and wherein different information is encoded on the said preselected line of the odd field from that encoded on the said preselected line of even field of each frame of the video portion of the encoded program and wherein the information encoded in one field of a program remains substantially invariant while the information encoded in the other field changes continually throughout the encoded program.

14. The method of claim 8 wherein the identifying code is encoded on 8 preselected line of the video portion of the encoded program and wherein such code occupies less than the full available space on said preselected lined and is recorded on a central portion of said preselected line.

15. The method of claim 9 wherein said identifying code includes a cyclic redundancy check byte and further including checking each received identifying code for error upon detection and decoding.

16. The method of claim 9 further including determining a quality index for each received encoded program, based on the quality of the received video portion of said program.

17. The method of claim 9 wherein said step of detecting and decoding the identifying code includes:
searching each line of the field of a received program between predetermined lines for determining the presence of an identifying code on one of such lines.

18. The method of claim 8 wherein said preselected line is between lines 10 and 20 of the video portion of the encoded program.

19. The method of claim 8 wherein said preselected line is in the vertical blanking interval.

20. An in-station system for automatically encoding and monitoring the transmission of television programs by a station having a video management system, comprising at the station:
means for encoding programs received at said station with identifying information and for dubbing the encoded programs to a storage medium compatible with the video library management system;
means for receiving the video signal of programs transmitted by said station;
means for detecting the presence of said identifying information on said video signal;' means for separating said identifying information from said received video signal; and data base means for storing information concerning the identity and transmission of said encoded programs.

21. The system of claim 20 wherein said encoding means includes means for encoding a line of the overscan portion of the video signal of such received program.

22. The in-station system of claim 21 wherein said encoded line is in the vertical blanking interval.

23. The in-station system of claim 20 wherein said means for detecting the presence of an identifying code includes means for searching the fields of the received video signals between preselected lines of said video signal for detecting the presence of an identifying code.

24. The in-station system of claim 20 including means for generating quality index for each encoded program based on the quality of the video signal for such program.

25. The in-station system of claim 20 wherein said means for receiving the video signal is located at said station premises.

26. The system of claim 20 wherein said station is a broadcast station and said means for receiving the video signal includes a tap at the broadcast antenna of said station.

27. The in-station system of claim 1 further including:
means for coupling said database means to a remote host computer for transmitting information stored in such database means to said host.