DVR-7000
7.3.4.2 Recording SystemThe RF signal read out from a disc is processed up to DVD physical
The basic flow of data with the DVR-7000 is similar to that with theformatting in the writer block, transferred via the ATAPI bus, and is
DVR-2000. Recordable media are DVD-R (Ver. 2.0) and DVD-temporarily stored in the SDRAM (stream buffer) of the ATAPI
RW (Ver. 1.0/1.1), and recording application formats are Videointerface LSI. Then, the data are transferred to the AV decoder and
decoded to video and audio digital data. Thus, for DVD-VR, the
Recording Format (DVD-VR) and Video Mode Recording Format.same path is used for recording and playback during data transfer
Only Video Mode Recording is possible with DVD-R discs, andfrom the recorder to the writer blocks. The playback speed of DVD-
DVD-VR recording is possible with DVD-RW discs (Video ModeVR is double normal speed (only for DVD-VR).
Recording is also possible with Ver. 1.1 DVD-RW discs). TheThe AV-decoded data pass through the same path regardless of the
available recording speed to discs is normal speed.applications used. The digital video signal enters the Graphics Engine
In DVD-VR recording, analog video and audio line input signals orLSI, where the overlay process with the GUI & OSD takes place. If
analog video and audio signals detected by the tuner are AD-a disc-navigation display is called by the user, video capture and
converted, input to the Graphics Engine LSI, processed with themultiscreen display processes are executed for the designated frame
frame TBC and 3DNR, then encoded and multimplexed in real time.(random designation possible) of each title. Then, the digital video
In the video and audio encoding block, based on the set recordingsignal is processed with 3DNR in the NTSC Encode LSI to be output
length or recording bit rate, the most suitable encoding parameter isas an analog video signal.
determined, and MPEG video encoding is made by variable bit rateAs to the audio signal, audio digital data to be output as an analog
(VBR). Compressed video stream and audio stream compressed bysignal are decoded in the AV decoder, and audio digital data to be
DDCE (Dolby Digital Consumer Encoder) are then packed andoutput as a digital signal are DIF-modulated after being decoded in
multiplexed, and are formed into a basic VOB (video object)the AV decoder, then either signal goes to the AUDIO interface
conforming to the Video Recording Format. In the video stream,LSI, where the signal to be output as a digital signal undergoes a
necessary information stipulated in the Video Recording Format,switching process, and for the signal to be output as an analog signal,
such as RDI (Real-time Data Information) in a VOB, is described.data are gathered for the level meter and switching process is
Everything up to this process is done by the MPEG Encoder LSI. Aexecuted. The signal is then output through the DAC.
stream sent from this MPEG Encoder LSI is temporarily stored in
the SDRAM (stream buffer) of the ATAPI interface LSI. The main
CPU controls transfer so that the downstream will not overflow,7.3.5.2 CD/Video-CD Playback
and the temporarily stored stream is then transferred to the writerPlayback of CD media is newly added for the DVR-7000. The basic
block via the ATAPI bus. As actual recording to a disc is donedata flow is similar to that of a DVD-video player. Playback speed
intermittently, a write command is issued when data reach certainof CD media is 4 times normal speed in CAV.
amount, and a mass of data are transferred simultaneously.As to CD-DA playback, the RF signal read out from a disc is EFM-
The data is formatted into the DVD physical format in the DVD-demodulated in the writer block. Then the signal to be output as an
ROM encoder of the writer block, then actually recorded on a discanalog signal is sent to the recorder block as a 3-line serial signal of
with the most suitable emission power of the laser diode and theIEC60958 format, and the signal to be output as a digital signal is
strategy. On the disc, data are recorded intermittently in blocks, andDIF-modulated in the writer block and then is sent to the recorder
these data blocks are linked with no linking loss.block.
In actual operation, one title is created by one sequence of a user'sThe signal to be output as an analog signal via the Audio interface
starting recording through stopping recording. If recording is paused,LSI enters the SRC, where the sampling rate is converted from 44.1
a chapter will be created. If the disc is removed from the unit, thekHz to 48 kHz. Then, the signal enters the Audio interface LSI again,
management information (file system and VR_MANGR.IFO, etc.),and is finally output through the DAC. The signal to be output as a
which is managed by the main CPU and which is necessary to playdigital signal also undergoes a switching process in the Audio
back the recorded video and audio signals, will be recorded on theinterface LSI, and then is output as DIF.
disc. Editing can be made on the originals and play lists. For editingAs to Video-CD playback, as with CD-DA playback, the RF signal
of a play list, only management information is updated and rewritten,read out from a disc is EFM-demodulated in the writer block. Then
and VOBs are not rewritten. Thus, nondestructive editing is possible.the CD-ROM data for Video-CD is then sent to the recorder block
as a 3-line serial signal of IEC60958 format, as with the signal to be
output as an analog signal. In the recorder block, the data are first
7.3.5 Playback Systemdecoded then sent to the AV decoder, where the data are decoded
7.3.5.1 DVD Playbackinto video and audio digital data. Then, the data pass and are
processed in the same way as with DVD playback and are then
The path for transferring AV decoder data in the DVR-7000 hasoutput.
largely been modified from that of the DVR-2000.
The path of DVD-video playback is the same as that of conventional
DVD-video playback: The RF signal read out from a disc is converted
into NRZI (non return to zero inverse) signal after passing through
the preamplifier, then is sent to the recorder block; There, the DVD
physical format is decoded. Then in the AV decoder, the signal is
decoded into digital video and audio data. This is basically the same
path as that the DVD-video player uses to play back a DVD-video
disc. The playback speed is normal speed.
During playback of a DVD-VR, the data-transfer path from the writer
block is the same as that in recording (via the ATAPI bus).
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