The certified enterprises are enterprises that submitted technologies
that performed outstandingly in evaluation tests under the following
conditions. JASRAC, which served as the project leader, has completed
its technology evaluation certification based on the final report submitted
by the NRI, which served as the project secretariat, and hereby announces
its conclusions.
1. Musical Works Used for the Tests
The musical works used as the assignments were recorded on a CD-R as
a WAV format file (44.1kHz/16bit/2ch) and distributed to participating
enterprises. The robustness test was conducted on 2 popular music compositions,
1 classical composition, and 2 compositions with distinctive acoustics.
The sound quality test was conducted on one of the compositions from
each of the aforementioned categories, namely popular music, classical
and distinctive acoustic. (The distinctive acoustic compositions used
as assignments were traditional Japanese music and percussion compositions.)
2. Overview of the Robustness Tests
The robustness test evaluated whether the data watermarked by the participating
enterprises could be extracted after the following processes, in the
following environment, under equal conditions for all submitted technologies.
- Processing in a mastering studio
- Processing in a broadcasting studio (and a prospective broadcasting
environment)
- Processing for distribution through the Internet and other networks
- Processing using commonly available consumer level equipment
The specific robustness testing items are as follows.
Robustness testing items
| Testing Item |
Overview of Processing Involved |
| D/A, A/D transition |
Digital>>Analog>>Digital |
| Altered number of channels |
Stereo (2ch)>> mono |
| Down sampling |
44.1kHz/16bit/2ch >>16kHz/16bit/2ch |
| Amplitude compression |
44.1kHz/16bit/2ch >> 44.1kHz/8bit/2ch |
| Time and pitch compression and decompression |
Time compression / decompression: ±10%
Pitch shift compression / decompression: ±10%
|
| Linear data compression |
MPEG 1 Audio Layer 3 (MP3): 128kbps
MPEG 2 AAC: 128kbps
ATRAC: Version 4.5
ATRAC 3: 105kbps
RealAudio: ISDN
Windows Media Audio: ISDN
|
| Non-linear data compression |
FM (FM multiple broadcast, terrestrial hertzian TV broadcast)
AM (AM broadcast)
PCM (Satellite TV broadcast: communications satellite, broadcasting
satellite)
|
| Characteristic transformation of frequency
response |
FM (FM multiple broadcast, terrestrial hertzian TV broadcast)
AM (AM broadcast)
PCM (Satellite TV broadcast: communications satellite, broadcasting
satellite)
|
| Noise |
White noise: S/N: - 40dB |
3. Overview of Audibility
- ABX test conducted
- The listener listens to a sound recording with no watermark
(A), a sound recording with watermarks embedded (B), and a sound
recording which is one of the two (X).
- The listener listens to A and B alternately twice for 40 seconds
each, and then listens to X for 40 seconds. The listener decides
whether X is A or B.
- Elimination of (correct) contingency responses
- In order to eliminate (correct) contingency responses, the above
tests were conducted 5 times for each participating enterprise.
- The listener is defined to have detected the embedded watermark
if the same listener correctly determines whether the watermark
is embedded or not on each of the 5 tests. Under this definition,
the significance of the responses are 95% or greater.
- 4 individuals each from the following occupation categories were
selected as Golden Ears and Silver Ears from the recording industry.
- Recording engineers
- Mastering engineers
- Synthesizer manipulators
- Audio critics
Inquiries: webmaster@nri.co.jp
Copyright(c) 2000 Nomura Research Institute, Ltd. All rights reserved.
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