IEC 61834-6:2000 pdf download

IEC 61834-6:2000 pdf download.Recording -Helical-scan digital video cassette recording systemusing 6,35 mm magnetic tape for consumer use(525-60,625-50,1125-60 and 1250-50 systems)-Part 6: sDL format.
3 Programme track data arrangement
3.1 IntroductIon
Each television frame is recorded on 5 tracks for the 525-60 system and 6 tracks for the 625-50 system.
The helical tracks are recorded with video, audio and system data as for the SD format in IEC 61834•2. The arrangement of a track Is as shown in IEC 61834•2 for each system.
Each track is numbered from the beginning track of the television frame in order. A track which has track number i (I — 0 to 4 for the 525-60 system or i — 0 to 5 for the 625-50 system) is referred to as track i.
The pilot frame is performed over two television frame periods for both systems. Placement of
FO. Fl and F2 tracks is shown in figure 1 for the 525-60 system, and figure 2 for the 625-50
system. In the 525-60 system, pilot frame 0 and pilot frame I alternate with each other. In the
625-50 system, pilot frame 0 repeats.
3.2 Labelling convention Same as IEC 61834-2.
3.3 AudIo sector
As IEC 61834-2 except for track pair number, The track pairs for two fields are numbered sequentially as shown in tables 5 and 6
3.4 Video sector
As IEC 61834-2 except for track pair number. The track pairs for two fields are numbered sequentially as shown In tables 5 and 6.
3.5 Subcode sector Same as IEC 61834-2.
4 AudIo Interface
Same as lEG 61834•2.
5 Video interface
Same as lEG 61834-2.
6 Audio signal processing
6.1 IntroductIon
The audio signal Is recorded in one audio block. The audio block is composed of five audio sectors In five consecutive tracks for the 525-60 system, or six audio sectors in six consecutive tracks for the 625-SO system Audio signal processing In the audio block Is as In lEO 61834-2.
6.2 Error correction code Same as IEC 6I8342.
6.3 RandomizatIon pattern Same as IEC 61834-2.
6.4 Audio encoding
This standard provides one mode of encoding audio data within the audio block. The encoding parameters are defined in table 7.
The mode is called 32k-2ch mode, as two channels 01 audio signal are recorded in an audio block with the sampling frequency of 32 kHz. The encoded data are expressed in 2’s complement arithmetic with 12 bits non-linear. The compression rule of 16 bits linear code to 12 bits non-linear code is shown in figure 16 of IEC 61834-2.
6.5 Audio channel allocation
6.5.1 AudIo block
The audio block is the physical recording channel for the audio signal on tape, In this standard, one audio block named CH1 is provided. The construction of the audio block is shown in table 8 which shows that an audio block accommodates signals f or two audio channels.
6.5.2 Channel allocation
The audio channels are named CHa and CHb. Encoded data In CHa correspond to encoded data V. and encoded data in CHb correspond to encoded data Z respectively in figure 18 in IEC 61834.2. The basic channel allocation rule for SD-2ch audio is described in table 9.
For the channel described as No intormation in CHb, all zero data, or the same data as Cha. may be recorded.
6.6 Frame structure
6.6.1 Relative audIo-vIdeo timing
Same as lEG 61834-2.
6.6.2 AudIo frame processing
This standard provides the same audio frame processing modes as IEC 6 1834-2.
Unlocked mode
Unlocked mode is applicable to 32k-2ch mode when the samp’ing frequency of the audio signal is not synchronous with the video frame frequency. The number of audio samples per frame is variable within the range between the maximum and the minimum limits shown in table 10. The number of audio samples per frame is rounded to the nearest integer. The recording capacity of audio data for each audio block corresponds to the maximum for 48k mode in IEC 61834-2. The unused data area in an audio block shall be filled with undefined values, 1 or 0”, (don’tcare data).