Cinavia, originally called Verance Copy Management System for Audiovisual Content (VCMS/AV),
is an analog
watermark
A watermark is an identifying image or pattern in paper that appears as various shades of lightness/darkness when viewed by transmitted light (or when viewed by reflected light, atop a dark background), caused by thickness or density variations ...
ing and
steganography
Steganography ( ) is the practice of representing information within another message or physical object, in such a manner that the presence of the information is not evident to human inspection. In computing/electronic contexts, a computer file, ...
system under development by
Verance since 1999, and released in 2010. In conjunction with the existing
Advanced Access Content System
The Advanced Access Content System (AACS) is a standard for content distribution and digital rights management, intended to restrict access to and copying of the post- DVD generation of optical discs. The specification was publicly released in ...
(AACS)
digital rights management (DRM) inclusion of Cinavia watermarking detection support became mandatory for all consumer
Blu-ray Disc players from 2012.
The watermarking and steganography facility provided by Cinavia is designed to stay within the audio signal and to survive all common forms of audio transfer, including
lossy data compression
In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data siz ...
using
discrete cosine transform,
MP3
MP3 (formally MPEG-1 Audio Layer III or MPEG-2 Audio Layer III) is a coding format for digital audio developed largely by the Fraunhofer Society in Germany, with support from other digital scientists in the United States and elsewhere. Origin ...
,
DTS, or Ogg
Vorbis
Vorbis is a free and open-source software project headed by the Xiph.Org Foundation. The project produces an audio coding format and software reference encoder/decoder (codec) for lossy audio compression. Vorbis is most commonly used in conj ...
. It is designed to survive
digital and analog sound recording and reproduction
Sound recording and reproduction is the electrical, mechanical, electronic, or digital inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects. The two main classes of sound recording ...
via microphones, direct
audio connections and
broadcasting
Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum ( radio waves), in a one-to-many model. Broadcasting beg ...
, and does so by using
audio frequencies
An audio frequency or audible frequency (AF) is a periodic function, periodic vibration whose frequency is human hearing range, audible to the average human. The International System of Units, SI unit of frequency is the hertz (Hz). It is the pr ...
within the
hearing range
Hearing range describes the range of frequencies that can be heard by humans or other animals, though it can also refer to the range of levels. The human range is commonly given as 20 to 20,000 Hz, although there is considerable variati ...
. It is
monaural
Monaural or monophonic sound reproduction (often shortened to mono) is sound intended to be heard as if it were emanating from one position. This contrasts with stereophonic sound or ''stereo'', which uses two separate audio channels to reproduc ...
and not a
multichannel codec.
Cinavia's
in-band signaling
In telecommunications, in-band signaling is the sending of control information within the same band or channel used for data such as voice or video. This is in contrast to out-of-band signaling which is sent over a different channel, or even o ...
introduces intentional
spread spectrum
In telecommunication and radio communication, spread-spectrum techniques are methods by which a signal (e.g., an electrical, electromagnetic, or acoustic signal) generated with a particular bandwidth is deliberately spread in the frequency d ...
phase distortion
In signal processing, phase distortion or phase-frequency distortion is distortion, that is, change in the shape of the waveform, that occurs when (a) a filter's phase response is not linear over the frequency range of interest, that is, the ph ...
in the
frequency domain
In physics, electronics, control systems engineering, and statistics, the frequency domain refers to the analysis of mathematical functions or signals with respect to frequency, rather than time. Put simply, a time-domain graph shows how a s ...
of each individual audio channel separately, giving a per-channel digital signal that can yield up to around 0.2 bits per second—depending on the
quantization level available, and the desired
trade-off
A trade-off (or tradeoff) is a situational decision that involves diminishing or losing one quality, quantity, or property of a set or design in return for gains in other aspects. In simple terms, a tradeoff is where one thing increases, and anot ...
between the required
robustness
Robustness is the property of being strong and healthy in constitution. When it is transposed into a system, it refers to the ability of tolerating perturbations that might affect the system’s functional body. In the same line ''robustness'' ca ...
and acceptable levels of
psychoacoustic
Psychoacoustics is the branch of psychophysics involving the scientific study of sound perception and audiology—how humans perceive various sounds. More specifically, it is the branch of science studying the psychological responses associated wit ...
perceptibility. It is intended to survive analog
distortion
In signal processing, distortion is the alteration of the original shape (or other characteristic) of a signal. In communications and electronics it means the alteration of the waveform of an information-bearing signal, such as an audio signa ...
s such as the
wow and flutter and
amplitude modulation from
magnetic tape sound recording
An audio tape recorder, also known as a tape deck, tape player or tape machine or simply a tape recorder, is a sound recording and reproduction device that records and plays back sounds usually using magnetic tape for storage. In its present- ...
. On
playback, no additional
audio filter
An audio filter is a frequency dependent circuit, working in the audio frequency range, 0 Hz to 20 kHz. Audio filters can amplify (boost), pass or attenuate (cut) some frequency ranges. Many types of filters exist for different audio a ...
s are used to cover up the distortions and
discontinuities introduced.
The signal survives
temporal masking
In audio signal processing, auditory masking occurs when the perception of one sound is affected by the presence of another sound.Gelfand, S.A. (2004) ''Hearing – An Introduction to Psychological and Physiological Acoustics'' 4th Ed. New York, ...
and
sub-band coding by operating on the
fundamental frequency
The fundamental frequency, often referred to simply as the ''fundamental'', is defined as the lowest frequency of a periodic waveform. In music, the fundamental is the musical pitch of a note that is perceived as the lowest partial present. I ...
and its
subharmonic overtone
An overtone is any resonant frequency above the fundamental frequency of a sound. (An overtone may or may not be a harmonic) In other words, overtones are all pitches higher than the lowest pitch within an individual sound; the fundamental i ...
s, and by dealigning the phase relationship between the strongest signal and its subharmonics. Each phase discontinuity introduced by the encoder will result in a corresponding pulse of
wideband
In communications, a system is wideband when the message bandwidth significantly exceeds the coherence bandwidth of the channel. Some communication links have such a high data rate that they are forced to use a wide bandwidth; other links ma ...
white noise
In signal processing, white noise is a random signal having equal intensity at different frequencies, giving it a constant power spectral density. The term is used, with this or similar meanings, in many scientific and technical disciplines ...
, so a further range of additional distortions are introduced as a
noise mitigation
Noise control or noise mitigation is a set of strategies to reduce noise pollution or to reduce the impact of that noise, whether outdoors or indoors.
Overview
The main areas of noise mitigation or abatement are: transportation noise control, ...
strategy to compensate. The desired hidden digital data signal is combined in the distortion step using a pre-determined
pseudorandom binary sequence
A pseudorandom binary sequence (PRBS), pseudorandom binary code or pseudorandom bitstream is a binary sequence that, while generated with a deterministic algorithm, is difficult to predict and exhibits statistical behavior similar to a truly rand ...
for audio
frame synchronization
In telecommunication, frame synchronization or framing is the process by which, while receiving a stream of framed data, incoming frame alignment signals (i.e., a distinctive bit sequences or syncwords) are identified (that is, distinguished fro ...
and large amounts of
forward error correction for the hidden data to be embedded. The watermark is only embedded when certain
signal-to-noise ratio thresholds are met and is not available as a
continuous signal
In mathematical dynamics, discrete time and continuous time are two alternative frameworks within which variables that evolve over time are modeled.
Discrete time
Discrete time views values of variables as occurring at distinct, separate "po ...
—the signal must be monitored for a period of time before the embedded data can be detected and recovered. Extraction of the hidden signal is not exact but is based on recovering the
convolutional code
In telecommunication, a convolutional code is a type of error-correcting code that generates parity symbols via the sliding application of a boolean polynomial function to a data stream. The sliding application represents the 'convolution' of t ...
s through statistical
cross-correlation.
The Blu-ray Disc implementation of Cinavia is designed to cover two use-cases: the first is the provision of a Cinavia watermark on all
movie theater soundtrack
A soundtrack is recorded music accompanying and synchronised to the images of a motion picture, drama, book, television program, radio program, or video game; a commercially released soundtrack album of music as featured in the soundtrack ...
s released via
film distribution
Film distribution (also known as Film exhibition or Film distribution and exhibition) is the process of making a movie available for viewing by an audience. This is normally the task of a professional film distributor, who would determine the marke ...
networks; the second use-case is for the provision of a Cinavia watermark on all Blu-ray Disc releases that points to the presence of an accompanying AACS key. If a "theatrical release" watermark is detected in a consumer Blu-ray Disc audio track, the accompanying video is deemed to have been sourced from a "
cam
Calmodulin (CaM) (an abbreviation for calcium-modulated protein) is a multifunctional intermediate calcium-binding messenger protein expressed in all eukaryotic cells. It is an intracellular target of the secondary messenger Ca2+, and the bin ...
" recording. If the "AACS watermark" is present in the audio tracks, but no accompanying and matching AACS key is found on the disc, then it is deemed to have been a "
rip" made by copying to a second
blank Blu-ray Disc.
, known hardware players which can detect Cinavia watermarks include the
PlayStation 3
The PlayStation 3 (PS3) is a home video game console developed by Sony Computer Entertainment. The successor to the PlayStation 2, it is part of the PlayStation brand of consoles. It was first released on November 11, 2006, in Japan, November ...
(began with v3.10 System Software), as well as newer
Blu-ray Disc players.
Overview
Cinavia works to prevent copying via the
detection {{Unreferenced, date=March 2018
In general, detection is the action of accessing information without specific cooperation from with the sender.
In the history of radio communications, the term " detector" was first used for a device that detected ...
of a
watermark
A watermark is an identifying image or pattern in paper that appears as various shades of lightness/darkness when viewed by transmitted light (or when viewed by reflected light, atop a dark background), caused by thickness or density variations ...
recorded into the analog audio of media such as theatrical films and Blu-ray Discs. The intent is to prevent all copying, both counterfeit copies and legal copies of one's own content (for example,
format shifting
Format shifting is the conversion of media files into different file format or data compression ( video coding format and audio coding format). This may be required to play the media on different devices, for example when converting or ripping aud ...
).
Verance claims on their website that, while the watermark is able to survive recording through microphones (such as
recording a film in a movie theater with a camcorder), as well as
compression
Compression may refer to:
Physical science
*Compression (physics), size reduction due to forces
*Compression member, a structural element such as a column
*Compressibility, susceptibility to compression
* Gas compression
*Compression ratio, of a ...
and
encoding
In communications and information processing, code is a system of rules to convert information—such as a letter, word, sound, image, or gesture—into another form, sometimes shortened or secret, for communication through a communication ...
, it is
imperceptible to human hearing, and the presence of the watermark does not affect audio quality.
When media with the watermark is played back on a system with Cinavia detection, its
firmware will detect the watermark and check that the device on which it is being played is authorized for that watermark. If the device is not authorized (such as not being an authorized
movie projector
A movie projector is an opto-mechanical device for displaying motion picture film by projecting it onto a screen. Most of the optical and mechanical elements, except for the illumination and sound devices, are present in movie cameras. Mod ...
in the case of a
cam bootleg, or not utilizing
AACS in the case of a
copy
Copy may refer to:
*Copying or the product of copying (including the plural "copies"); the duplication of information or an artifact
**Cut, copy and paste, a method of reproducing text or other data in computing
**File copying
**Photocopying, a pr ...
of a commercial Blu-ray Disc or
CSS in the case of a copy of a commercial
DVD
The DVD (common abbreviation for Digital Video Disc or Digital Versatile Disc) is a digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can store any kind ...
), a message is displayed (either immediately or after a set duration) stating that the media is not authorized for playback on the device and that users should visit the Cinavia web page for more information. Depending on the device and firmware, once the message is triggered, the audio may be muted, or playback may stop entirely.
Messages
Following an intervention by the Cinavia+AACS system, one of four messages is displayed to reflect the specific situation in which a watermark was detected. The messages are numbered "Cinavia message code 1–4",
allowing the messages themselves to be easily translated for consumers in different languages:
# Message Code 1: Playback stopped
—Shown when theatre- or hotel-distributed audio content is being played back on a consumer playback device.
# Message Code 2: Copying stopped
—Shown when theatre- or hotel-distributed audio content is being recorded by a consumer recording device.
# Message Code 3: Audio muted
—Shown when consumer-sold audio content is being played back from an optical disc, without the matching AACS key present at the centre of the disc.
# Message Code 4: Copying stopped
—Shown when consumer-sold audio content is being recorded by a consumer recording device.
Licensing
For Cinavia the owners Verance make their money through licensing agreements with several sections of the entertainment and media industry. these licence costs due to Verance were $10,000–$300,000 per manufacturer of Blu-ray Disc players—for the rights to embed the Cinavia detection system—plus additional software costs for the implementation itself.
Production facilities need to pay $50 for each audio track that is watermarked with Cinavia.
Distribution houses must finally pay $0.04 per disc with Cinavia watermarked content included.
Technical aspects
Verance claims Cinavia has the following features:
* Only a single channel of audio is required to detect the watermark.
* The watermark is able to survive re-recording through a microphone.
* The watermark can be detected through "the production, duplication, distribution, broadcast, and consumer handling of recorded content".
(In the white paper for their DVD-Audio Detector Compliance Verification Suite all tests are single-channel files.
)
* Different copies of otherwise identical works can be distinguished.
DVD-Audio
The data throughput for a watermarking system used for
DVD-Audio
DVD-Audio (commonly abbreviated as DVD-A) is a digital format for delivering high-fidelity audio content on a DVD. DVD-Audio uses most of the storage on the disc for high-quality audio and is not intended to be a video delivery format.
The st ...
requirement is for "Watermark Output: 3 water-mark data bits per 15 seconds (2 CCI bits and 1 SDMI Trigger Bit)". The two CCI bits in the example contain Digital Copy Control Information, while the succession of SDMI bits contains
Secure Digital Music Initiative data when reconstructed. Also in the Compliance Verification Suite the lowest sample rate test is at 16,000 samples per second with 16 bits per sample.
This could indicate that the bandwidth requirements top out at 8 kHz.
History
On 5 June 2009, the licensing agreements for AACS were finalized, which were updated to make Cinavia detection on commercial Blu-ray Disc players a requirement.
On 3 July 2009, Maxim Anisiutkin published an open source DVD Audio watermark detector and neutralizer computer program to the SourceForge web site. The software package contains a detailed description of the method and embedding parameters used in creating the DVD Audio or SDMI (
Secure Digital Music Initiative) watermark, which was created by Verance Inc and was the earlier version of the Cinavia watermarking technology.
From January 2013 onwards, attempts were made by third-party software suppliers to make use of existing bugs and loopholes in Blu-ray Disc players to avoid Cinavia message triggering, but without any attempt being made at precisely removing the Cinavia signal from the audio. These attempts included iDeer Blu-ray Player,
DVDFab and
AnyDVD
AnyDVD is a device driver for Microsoft Windows which allows decryption of DVDs on the fly, as well as targeted removal of copy preventions and user operation prohibitions (UOPs). With an upgrade, it will also do the same for HD DVD and Blu-r ...
HD (version 7.3.1.0) which used workarounds to avoid Cinavia-enabled software Blu-ray Disc players from triggering Cinavia detection messages.
In August 2013, DVD-Ranger released a
white paper
A white paper is a report or guide that informs readers concisely about a complex issue and presents the issuing body's philosophy on the matter. It is meant to help readers understand an issue, solve a problem, or make a decision. A white pape ...
detailing their methods for detecting, and subsequently removing, the present Cinavia signal from audio files.
The DVD-Ranger CinEx beta software synchronises and detects the Cinavia signal in the same way as a consumer Cinavia detection routine; these identified parts of the audio stream are permanently removed, removing the Cinavia signal. Post-processing can be used to try to "fill-in" the audible gaps created.
There are claims
that Cinavia can be removed using open source software like
Audacity with an extracted audio file from a video source. The audio file is processed by decreasing pitch by 13%; the processed audio file is then merged back into the video source. This renders the Cinavia watermark unreadable, however the reduction in pitch can be easily noticed.
References
Further reading
#
#
#
# .
#* Continued and republished as
#
/www.google.com/search?tbo=p&tbm=pts&hl=en&q=rade+petrovic Google patents search for "Rade Petrovic"#
/www.google.com/search?tbo=p&tbm=pts&q=Babak+Tehranchi Google patents search for "Babak Tehranchi"#
#
#
#
External links
*
Verance
*
*
*
*
{{Blu-ray
Digital rights management systems
Digital watermarking
Compact Disc and DVD copy protection
Blu-ray Disc