Abstract: A digital video tape recorder ("VTR") that selects data useful for generating images during trick playback operation and records the data in trick play tape segments arranged on a tape to form fast scan tracks and multi-speed playback tracks. Each fast scan track comprises trick play tape segments located on a diagonal, relative to the length of the tape, of the same angle as the angle at which the heads of a VTR are expected to pass over the tape during trick play operation at a specific speed and direction of operation. Each multi-speed playback track comprises a plurality of trick play tape segments arranged parallel to the length of the tape. Data which is used for at least one mode of trick play operation is recorded in each trick play tape segment. Each fast scan track and multi-speed track crosses multiple normal play tracks.

Abstract: Methods and apparatus for implementing a reduced cost HDTV/SDTV video decoder are disclosed. The described joint video decoder is capable of decoding HDTV pictures at approximately the resolution of standard definition television pictures and can be used to decode HDTV and/or SDTV pictures. The described video decoder may be used as part of a picture-in-picture decoder circuit for providing picture-in-picture capability without providing multiple full resolution video decoders. The reduction in decoder circuit complexity is achieved through the use of a plurality of data reduction techniques including the use of a preparser, downsampling, and truncating pixel values.

Abstract: Methods and apparatus for reducing the complexity of decoder circuitry and video decoder memory requirements are disclosed. The described video decoders are capable of decoding HDTV pictures at approximately the resolution of standard definition television pictures and can be used to decode HDTV and/or SDTV pictures. The described video decoder may be used as part of a picture-in-picture decoder circuit for providing picture-in-picture capability without providing multiple full resolution video decoders. The reduction in decoder circuit complexity is achieved through the use of a plurality of data reduction techniques including the use of a preparser, downsampling, and truncating pixel values.

Abstract: Methods and apparatus for processing digital video data to reduce the amount of video data required to represent a video frame by representing a frame or pair of field pictures into a single field of a pair of field picture are described. To prevent the second field of the field picture from being displayed a DSM byte associated with the field picture is set so that only the field representing the video frame is displayed. In accordance with the present invention, a field, e.g., a transparent predictively coded field is used as the field picture which is not displayed. In this manner, very little data is required to represent the field picture that is not displayed. When the received frames are represented as pairs of field pictures a single field of the pair of field pictures is selected to represent the video frame with the other field picture being replaced with a field which requires very little data.

Abstract: Methods of operating a digital video recording and playback device, such as a video tape recorder, to arrange trick play data into one or more groups, to generate error correction bits for each group of trick play data, e.g., a group of trick play data blocks, and to correct the data after being read back using the error correction bits is disclosed. The trick play data blocks are made to be smaller than normal play data blocks with multiple trick play data blocks being equal in size to a single normal play data block. By making a group of trick play data blocks equal in size to a single normal play data block, the group of trick play data blocks may be processed as a unit by the same error correction circuitry and in the same manner used to process individual normal play data blocks. In accordance with one embodiment, the error correction bits for a group of trick play data blocks are calculated treating the data in the group of trick play data blocks as a single unit.

Abstract: Digital video tape recorder apparatus that generates commands to instruct a television receiver to perform special processing, e.g., processing designed to enhance image quality, on video data received from the digital video tape recorder during trick play operation is disclosed. The commands from the video tape recorder inform the television receiver that the video tape recorder is operating in trick play mode and that video processing not performed on normal play video data output by the video tape recorder during normal play operation should be performed on the trick play video data which is output during trick play operation. The video data output during trick play operation is a subset of the normal play video data. The video processing commands output during trick play operation instruct a receiver to perform video processing intended to compensate for normal play data intentionally omitted by the video tape recorder from the trick play video data because of, e.g.

Abstract: Method for increasing the recording time of a digital video tape recorder ("VTR") and for supporting multiple normal play modes of digital VTR operation, e.g., a standard play mode of operation and one or more long play modes of operation. To achieve long play mode operation data reduction is performed on a received full rate video data stream to generate a reduced rate video data stream. Data reduction is performed using data prioritization and selection, requantization of full rate data stream, and/or by selecting data to be included in the reduced rate data stream as a function of what portion of a video frame the data represents. The reduced rate data stream is generated to be compliant with the data format of the full rate data stream. During long play mode recording operation the data in the reduced rate data stream is recorded on a tape at the same tape data density as used during standard mode VTR operation.

Abstract: Method for increasing the recording time of a digital video tape recorder ("VTR") and for supporting multiple normal play modes of digital VTR operation, e.g., a standard play mode of operation and one or more long play modes of operation. To achieve long play mode operation data reduction is performed on a received full rate video data stream to generate a reduced rate video data stream. Data reduction is performed using data prioritization and selection, requantization of full rate data stream, and/or by selecting data to be included in the reduced rate data stream as a function of what portion of a video frame the data represents. The reduced rate data stream is generated to be compliant with the data format of the full rate data stream. During long play mode recording operation the data in the reduced rate data stream is recorded on a tape at the same tape data density as used during standard mode VTR operation.

Abstract: A video recorder compatible receiver for receiving video data from a video recorder such as a video tape recorder ("VTR"). The receiver includes an error concealment circuit, a digital VTR port adapted for coupling to a VTR and/or a tuner module. The receiver receives digital video data from the VTR by either the digital VTR port or the tuner module. VTR commands may also be received from a VTR. Upon receiving a VTR command indicating that the VTR is operating in trick play mode or upon detecting video data that is indicative of VTR trick play operation, the error concealment circuit of the receiver disables normal play error concealment and enables trick play error concealment. The error concealment circuit may perform temporal and spatial filtering on the video data received from the VTR when trick play error concealment is enabled.

Abstract: A method for reducing noise in a reference frame of video information by determining the mean absolute difference, MAD.sub.o, between each block in the reference frame and identically located blocks in adjacent frames. If MAD.sub.o is <A, the block in an adjacent frame is held for averaging with the block in the reference frame, but if MAD.sub.o for the block is >A, a search is made for a block in the adjacent frame that matches the block in the reference frame. This is labelled MAD.sub.min. If MAD.sub.o for the block in the adjacent frame is <BMAD.sub.min, the matching block is not used in the average. If MAD.sub.o is not <BMAD.sub.min, the matching block can be used in the average, but preferably this is not done if MAD.sub.min exceeds a value C. The values of A, B and C are determined by experience for the block size used.