Abstract:
A method and device for determining whether an incorrect recording occurred on a recording device. Electronic Program Guide (EPG) information is used to select a program to be recorded. Corrected EPG data is sent after the recording and compared to the time, channel and length of recording to determine if an incorrect recording took place due to a change in scheduling. If so the recording device searches the EPG data for another showing of the program and if found records the next showing.

Description:
BACKGROUND OF THE INVENTION 
     Many known recording systems provide programming information in the form of Electronic Program Guides (EPG) to the recording system. Some EPGs are broadcast continuously such as those from the cable operator while others are downloaded to the recording system on some periodic basis. Many EPGs are interactive and let the user select a program to record from the EPG by moving a highlighted cursor to a program name and selecting the program. 
     Personal Video Recorders (PVRs) are becoming increasingly popular such as the TIVO personal video recorder. PVRs use a hard drive to record programs rather than using a tape such as in a VCR. The PVRs also use EPGs and make a daily phone call to download the EPG. The user scrolls through the PVR&#39;s EPG to select programs that are to be recorded. These systems simplify the recording process by no longer requiring the user to enter the date, start time, length, and channel number of the program to be recorded. Instead, by scrolling through the EPG, the user selects the title that the user wishes to record. The PVR automatically knows the date, start time, length and channel number from the EPG and records the program. 
     There are problems with the known systems. Since the program information is loaded on some periodic basis such as early in the morning every day, any subsequent change to that day&#39;s schedule is not know to the EPG. This leads to cases when material is unsuccessfully recorded such as when material not requested gets recorded and material requested does not get recorded. For example, when a baseball game extends to 15 innings instead of the normal 9, the game can run 2-3 hours over schedule, preempting other programs that the user may wish to record. The PVR will end up recording the late innings of this game instead of the original program the user wanted recorded. There is no way to detect whether the PVR recorded the incorrect program so that it can record the rescheduled program in the future. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the invention to provide a recording device that will automatically record any rescheduled shows that were originally intended to be recorded but due to rescheduling or errors in the EPG they were not recorded. 
     It is another object of the invention to send a corrected version of the previous day&#39;s EPG to the recording device. The recording device will then detect when it recorded an incorrect show and either delete the show and/or set itself up again to record the rescheduled show by searching the EPG for the rescheduled show. 
     It is a further object of the invention to send a complete corrected EPG and the recording device will compare the previously sent EPG to the corrected EPG to find discrepancies. 
     It is yet another object of the invention to send only the changes to the previous day&#39;s EPG to the recording device. 
     Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification. 
     The invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others, and the apparatus embodying features of construction, combinations of elements and arrangement of parts that are adapted to effect such steps, all as exemplified in the following detailed disclosure, and the scope of the invention will be indicated by the claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a better understanding of the invention reference is made to the following drawings. 
     FIGS. 1A and 1B show a PVR in accordance with the invention; 
     FIG. 2 a  shows an EPG schedule which is sent to the PVR on Wednesday morning; 
     FIG. 2 b  shows the selection of a tennis match to be recorded on Wednesday evening; 
     FIGS. 2 c  and  2   e  show several forms of the corrected EPG data which may be sent to the PVR on Sunday morning; 
     FIG. 2 d  shows that the PVR has selected the rescheduled tennis match to be recorded based on the corrected EPG data; and 
     FIG. 3 shows a flow chart in accordance with the invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 a  shows a video recording system in accordance with a preferred embodiment of the invention. A PVR  10  is connected to a television  11  and to the phone system  12  (or other communication path) to receive the EPG data. The EPG  13  is displayed on the television  11  and provides a cursor for navigating through the program menus. The broadcast source (e.g. TV antenna, cable, satellite)  15  provides the TV content to be recorded. 
     FIG. 1 b  shows some components of the PVR  10 . It includes a controller  30 , a remote control  2 , a modem  14 , an EPG memory  20 , an EPG correction memory  21 , a comparator  24 , an on-screen display generator  26 , a record list memory  27 , a clock  31 , a tuner  32 , an encoder  33 , a hard disk  23  and a decoder  34 . The PVR  10  makes a telephone call via telephone line  12  and modem  14  each morning to download the EPG to the EPG memory  20 . Using the user interface  13  generated by the on-screen generator  26  a user navigates through the menus to select a program to be recorded. The PVR  10  records the selected program and stores it on the hard drive  23 . The following morning another telephone call is made to download new EPG data and corrected EPG data for the previous day&#39;s rescheduling of programs. The corrected EPG data is stored  21  and compared  24  with the previous day&#39;s recordings  27 . The comparator  24  determines whether or not the corrected EPG data involves the same time and channel number of any previous day&#39;s recording. If it did, then the PVR searches in the EPG memory  20  for the program title which was supposed to be recorded previously to see if it is in the upcoming program schedules. If it finds the rescheduled program or another showing of the same program, or a subsequent episode it automatically programs itself to record that showing. 
     FIGS. 2 a - 2   e  show an example of the EPG&#39;s and corrected EPG. At 8 PM on Wednesday night there are various shows that can be selected to be recorded. None of these shows are selected but there is a baseball game which will be shown on channel 3 which starts at 8 PM. The broadcaster anticipates that the baseball game will end at 10 PM, so as seen in FIG. 2 b , the tennis match is supposed to be shown next on channel 3 at 10 PM. The user navigates through the EPG and selects the tennis match for recording and the PVR knows that the tennis match is on Wednesday night at 10 PM on channel 3 for two hours. The PVR then records this channel during this time period. 
     Thursday morning a telephone call is made and new EPG information is downloaded along with corrected EPG data. The corrected EPG data FIGS. 2 c  and  2   e  indicates that the Wednesday night baseball game on channel 3 did not end at 10 PM, but ended at 11:30 PM. This is 1 ½ hours into the tennis match. This corrected EPG data is shown in FIGS. 2 c  and  2   e  but typically not displayed to the user. It is more likely sent in a database format as shown in FIG. 2 e . The PVR compares the corrected EPG data to the previous programs selected to be recorded to determine if there was a program selected to be recorded on Wednesday night on channel 3 from 10:00-11:30 PM. Since the user selected to record the tennis match at this time, the PVR now knows it recorded an incorrect program from 10:00-12:00 midnight or didn&#39;t record the entire tennis match because it started late. At this point the PVR could delete the recording (i.e. permit recording over the program erroneously recorded) it recorded Wednesday night or keep it if part of the tennis match was in fact recorded. In this case the corrected EPG data shows that the baseball game ended at 11:30 p.m. and the news was shown from 11:30 p.m. to 12 midnight. The PVR then searches the new EPG data for the tennis match. The PVR finds that it was rescheduled to be shown on channel 3 at 10 PM on Thursday. It automatically programs itself to record this showing of the tennis match on Thursday night. If the program that the user selected to record was a television show such as “ER” (instead of the tennis match) on Wednesday night and ER was preempted by the baseball game, ER may not be rescheduled but the PVR would just select the next week&#39;s showing of “ER” to record. 
     FIG. 3 shows a flow chart of a preferred embodiment of the invention. The PVR receives the EPG data  40 . The user selects from the EPG data a program to be recorded  41 . The PVR knows from the program title, the channel number, time, and program length, the length of time it is supposed to record and records at that time  42 . The PVR then receives corrected EPG data  43 . The PVR compares the corrected EPG data to either the previous EPG data to find the changes and then compares the changes to the program record list  44  or if only the changes have been sent then compares the changes to the programs that were selected to be recorded  44 . From this comparison  44  the PVR determines whether any programs were incorrectly recorded. If not then the PVR does nothing  46 . If the comparison  44  reveals that there was an incorrect recording, the PVR searches the new EPG data for the rescheduled showing of the program or the next time the program is to be shown  45  and sets itself up to record the next showing. The PVR then can erase or write over the incorrect recording  47  and/or inform the user when an erroneous or incomplete recording has occurred and if and when a corrected recording will occur. The system may also include an option for the user to delete the erroneous recording. 
     The invention has been described with reference to a PVR but obviously it can be implemented with other recording devices such as VCR&#39;s and perhaps in the future DVD&#39;s etc. In addition there are many ways to receive the EPG&#39;s and the corrected EPG data such as via the cable connection, the internet or, as described, over the telephone lines etc. 
     It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in carrying out the above method and in the construction set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.