IEC 62356-2 pdf download – Video recording – 12,65 mm type D-11 format – Part 2: Picture compression and data stream

IEC 62356-2 pdf download – Video recording – 12,65 mm type D-11 format – Part 2: Picture compression and data stream
1 scope
This International Standard specifies the compression of a high-definition source format to adual-channel packetized data stream format which is suitable for recording on disc and tapestorage devices including the Type D-11 tape recorder. The specification includes a numberof basic packetizing operations including the shuffling of the source data prior to compression,both to aid compression performance and to allow error concealment processing in the
decoder. The standard also includes the processes reauired to neeadeenh promessing in theD-11 packetized data format into a high-definition output signal.
This standard supports high-definition source formats using 1 920×1 080 pixels and thesampling structures as specified in SMPTE 274M and RP 211at the following picture rates:
.24/1,001/PsF;
24/PsF;
25/PsF;
30/1,001/PsF;. 50/I;
60/1,001/1
where ‘PsF’ indicates Progressive segmented Frame and ‘T’ indicates Interlaced.
The data packet format specified by this standard is used as the source data stream for theassociated document which maps this Type D-11 packetized data-stream format together withAES3 data over sDTI.
2Normative references
The following referenced documents are indispensable for the application of this document.For dated references,only the edition cited applies. For undated references, the latest editionof the referenced document (including any amendments) applies.
SMPTE 292M:1998,Television – Bit-Serial Digital Interface for High-Definition TelevisionSystems
SMPTE 274M:1998，Television – 1920 x1080 Scanning and Analog and Parallel Digitallnterfaces for Multiple Picture Rates
SMPTE RP 211:2000，Implementation of 24P，25P and 30P Segmented Frames for 1920 x1080 Production Format
SMPTE 12M:1999,Television,Audio and Film-Time and Control Code
SMPTE RP 188:1999，Transmission of Time Code and Control Code in the Ancillary DataSpace of a Digital Television Data Stream
3 Introduction
This standard specifies the encoding and decoding of high-definition source formats via compression into a bit rate in the range 1 1 2~1 40Mb/s for recording on a Type D-1 1 digital tape recorder. The recorded bit rate is related to the source picture rate according to Table 1 .
ln common with other compression systems, the Type D-11 encoding process uses intra-frame coding (i.e. the coding is bound by the frame period) using the Discrete CosineTransform (DcT) to provide the data de-correlation required for efficient compression. Thecoefficients are quantized and variable length coded (VLC) to produce the basic output dataformat.
The source pictures are subsampled prior to compression coding.This reduces the number ofcoded pixels and allows the number of bits-per-pixel value to be raised in proportion. Theluminance source sampling grid of 1 920×1 080 pixels is reduced to 1 440× 1 080 pixels.For each chrominance channel, the source sampling grid of 960 x 1 080 pixels is reduced to480 × 1 080 pixels. In the decoder, the output pixel sample grid is restored back to the sourceformat of 1 920×1 080 pixels by interpolation following the compression decoding process.
The compressed data format specified by the output of the compression encoder is of a formwhich allows direct mapping into the basic block structure as defined in the Type D-11 digitalrecorder document.
4Encoding
4.1overview
Type D-11 source data for compression shall comprise only the production aperture area asdefined by SMPTE 274M.
NOTE DCT coding uses a data block size which allows exactly 1 080 lines to be coded.
The source formats comprise luminance (Y) and chrominance (Cp,CR) component signals asdefined by SMPTE 274M and SMPTE RP211.
Type D-1 1 source picture rates for compression shall be constrained to the following values:
• 24/1 001 frames per second in the segmented format as defined by SMPTE RP 21 1 ;
• 24 frames per second in the segmented format as defined by SMPTE RP 21 1 ;
• 25 frames per second in the segmented format as defined by SMPTE RP 21 1 ;
• 30/1 001 frames per second in the segmented format as defined by SMPTE RP 21 1 ;
• 50 fields per second in the interlaced format (a.k.a. 50/I) as defined by SMPTE 274M;