DIGITAL AUDIO INTERFACE
FOR
DRA ENCODED AUDIO BITSTREAMS
Contents
•
•
•
•
Introduction of DRA and 100/1447/NP
Industrialization progress of DRA technology
Why we need an identifier of IEC 60958
Details of IEC 61937 DIF for DRA
2
Contents
•
•
•
•
Introduction of DRA and 100/1447/NP
Industrialization progress of DRA technology
Why we need an identifier of IEC 60958
Details of IEC 61937 DIF for DRA
3
DRA （Digital Rise Audio） technology
An Audio compressing technology as China industry standard
Name of the Standard： 《Specification for Multichannel Digital Audio Coding Technology 》
Number of the Standard ： SJ/T11386-2006
Issued date：
Jan 4, 2007
Issued department：
Ministry of Information Industry of PRC (Now named as “MIIT”)
It will be published as China national standard at the end of this year
DRA Audio compressing technology can be used in:
DAB (Digital Audio Broadcasting)
MMB (Mobile Multimedia Broadcasting),
NM (Network Multimedia),
DTV
DVD
4
Technical specification and audio quality
sampling rate
8~192kHz
bit rate
32~9612kpbs
sampling precision
24bit
channel numbers
64.3 —— normal channels: 64, low frequency channels
(LFE):3
• Formal listening test in China —— MOS score = 4.9/5.0
(July, 2007: by State Administration of Radio Film and Television)
• Also passed the BDA‘s audio quality assessments in Japan (Feb.17,
2008: Tokyo) and USA (April, 2008: Hollywood)
5
Position for 100/1447/NP
Data-type
Value of
PC bit 0-4
Subdata-type
Value of
PC bit 5-6
Contents
1
0
AC-3 data
(assigned by IEC 61937-3)
7
0
MPEG-2 AAC
(assigned by IEC 61937-6)
11
0
DTS Type I
(assigned by IEC 61937-5)
14
0
ATRAC
(assigned by IEC 61937-7)
Selected
from 23-26
0-3
DRA data
(apply for IEC 61937-x)
partly
enlarged
Copy from <IEC 61937-2: 2007>
6
Contents
•
•
•
•
Introduction of DRA and 100/1447/NP
Industrialization progress of DRA technology
Why we need an identifier of IEC 60958
Details of IEC 61937 DIF for DRA
7
From BD
"We are very happy that DRA, an original Chinese audio coding technology,
has passed the BDA technical evaluation. The BDA is now taking final steps to
formally adopt DRA as part of the format. “———
Matsumura-san （Pioneer）
chair of BDA China Task Force
“DigiRise DRA (DRA) digital audio coding technology has passed an
important technical evaluation” ———
Kawawuchi-san（SONY）
CFO of BDA
"We will continue to work closely with BDA in order to complete the
remaining procedures and ensure that DRA technology will be adopted by
the Blu-ray Disc format as soon as possible.“———
Songhe Yin
vice president of China Hualu Group.
Blu-ray Disc Association (BDA) has accepted DRA audio coding technology as one part of BD Specification
8
From SMPTE
MPEG available identifier for DRA
• TS format identifier (assigned by SMPTE)：
0x44524131(“DRA1”) , used in PMT of MPEG-2
TS steam, 2008
• After that, BDA has added TS format
identifier into BD draft Specification.
9
CMMB project in China
• DRA : the mandatory technology in CMMB standard in China;
• DRA hardware encoder for CMMB：
• receiving terminal for CMMB： DRA-CMMB receiver
10
CMMB project
Other copartners in CMMB project
DRA-CMMB signals are broadcasting in more than 30 cities in China,2008
11
DTV application in China
• DTV receiver specification: DRA —— audio part
• Broadcasting 5.1 channel DRA-DTV signal: Guangdong
Province
• DRA-DTV chips providers signed agreement on chip design
12
Contents
•
•
•
•
Introduction of DRA and 100/1447/NP
Industrialization progress of DRA technology
Why we need an identifier of IEC 60958
Details of IEC 61937 DIF for DRA
13
identifier for DRA in IEC 60958
• Lots of requirements for receiving and/or
transmitting DRA through IEC 60958 interface
14
If IEC 61937 DIF for DRA issued by TC100:
More manufactures can develop chips or terminals supporting IEC 61937 DIF for DRA
More people can use and be familiar with IEC 61937 DIF for DRA
IEC 61937 DIF will become more popular
15
Contents
•
•
•
•
Introduction of DRA and 100/1447/NP
Industrialization progress of DRA technology
Why we need an identifier of IEC 60958
Details of IEC 61937 DIF for DRA
16
Position of DRA new proposal
IEC 60958-1
Digital audio interface: General
IEC 61883-6
A/M Protocol
IEC 60958 series conformant
LPCM Audio
IEC 60958-3
Consumer applications
IEC 61937-x
DRA
IEC 61937-3
AC-3
IEC 60958-4
professional applications
IEC 61937-4
MPEG-1,-2 audio
Non-LPCM audio
IEC 61937-1
General
IEC 61937-5
DTS
IEC 61937-2
Burst-info
IEC 61937-6
MPEG-2 AAC
IEC 61937-7
ATRAC and ATRAC 2/3
IEC 62105/EN 50255
RDI
Data
17
Details of IEC 61937 DIF for DRA
Pa
Pb
Pc
Bit 0 of Pa
Pd
DRA
Burst_payload
DRA frame
Pa
Pb
Pc
Pd
DRA
Burst_payload
stuffing
DRA frame
Regular rate of the DRA
Repetition period of the burst
18
Details of IEC 61937 DIF for DRA
Bits of Pc
Value
0-4
Reference
point R
Repetition period
of data-burst
in IEC 60958
frames
Data-type
23-26
5-6
7-15
Contents
Depends on
Subdata-type
DRA
Subdata-type
002
Subdata-type for DRA
Bit 0 of Pa
1024
012
Subdata-type for DRA half-rate low sampling
frequency
Bit 0 of Pa
2048
102
Subdata-type for DRA quarter-rate low sampling
frequency
Bit 0 of Pa
4096
112
Reserved
In accordance with IEC 61937-1 and
IEC 61937-2
19
Thanks
20
What we need IEC help us?
– Get the official number of Data-type
Bits 0-4 of Pc
Pa
Pb
Pc
Bit 0 of Pa
Pd
DRA
Burst_payload
DRA frame
Pa
Pb
Pc
Pd
DRA
Burst_payload
stuffing
DRA frame
Regular rate of the DRA
Repetition period of the burst
21

Document 4478908