Abstract: Techniques to transmit encoded data along a transmission medium and decode the transmitted data along the transmission medium are provided. Some techniques include logic to encode data transmitted along a transmission medium, such as a fiberoptic line or cable, where the encoding is pursuant to a conversion between a first and second colorspace. The logic may further be configured to decode the data once it is received at a node along the fiberoptic line, where the colorspace conversion provides the basis, key, or cipher for preforming the decoding operation. The logic may be further configured to alter the encryption and decryption basis, key, or cypher by altering the colorspace scheme defining the encoding (and by extension the decoding) during transmission, including a transmission that takes place after a previous transmission governed by the previously defined (and subsequently altered) colorspace conversion scheme. Other embodiments are described and claimed.

Abstract: [Object] To achieve both continuity of the system running and reduction of the running cost under a situation in which a storage region on a network is used as a saving destination of various kinds of data. [Solution] Provided is a an information processing device including: a signal processing unit that encodes a first signal including one or more non-zero components based on first data and one or more zero components into a second signal having a shorter signal length than a signal length of the first signal on the basis of a matrix generated in accordance with a predetermined condition; a data generation unit that generates one or more pieces of second data by associating information indicating positions of signal elements in the second signal with the signal elements in the second signal; and a transmission unit that transmits each of the one or more generated pieces of second data to one or more devices connected via a network.

Abstract: In some examples, a system includes a color cluster learning engine and a color recognition engine. The color cluster learning engine may be configured to obtain a set of training images, process the training images to obtain clusters of pixel colors for the training images, identify learned color clusters from the clusters of pixel colors obtained from the training images, and label the learned color clusters with color indicators. The color recognition engine may be configured to receive an input image for color identification, process the input image to obtain a particular cluster of pixel colors that covers the highest number of pixels in the input image, match the particular cluster to a particular learned color cluster labeled with a particular color indicator, and identify a color of the input image as specified by the particular color indicator.

Abstract: Example embodiments provide systems and methods for emphasis modification of an informational overlay in augmented reality displays. In an example method, an informational overlay is presented atop a scene on a display device. The informational overlay includes at least one of a graphical element or a textual element to partially obscure the scene. Scene change data indicating a change in the scene is accessed. Based on the scene change data, a visual emphasis on the display device of at least a portion of the informational overlay relative to the scene is modified.

Abstract: A method and system for cryptographically indexing, searching for, and retrieving documents is provided. In some embodiments, an encryption system is provided that generates a document index that allows users to retrieve documents by performing encrypted queries for keywords associated with the documents. In some embodiments, each keyword maps to the same number of encrypted document identifiers. In some embodiments, an extractor graph is employed to map an indication of each keyword to a number of buckets storing encrypted document identifiers. In some embodiments, an order-preserving encryption system is provided. The encryption system uses an ordered index that maps encrypted instances of ordered attribute values to documents that are associated with those values. The ordered index enables queries containing query operators that rely on order, such as less than (“<”) or greater than (“>”), to be successfully performed on encrypted attribute values.

Abstract: The present disclosure discloses an anti-peeping display system includes an anti-peeping display, anti-peeping glasses and a controller. The anti-peeping display includes a first polarizer and a first driving device driving the first polarizer to rotate. The anti-peeping glasses include a second polarizer and a second driving device driving the second polarizer to rotate. When judging that both of the obtained display password and the obtained glasses password are correct, the controller is configured to control the first polarizer and the second polarizer to rotate at a same angular velocity; otherwise, control the first driving device and the second driving device to rotate at different angular velocities.

Abstract: An information display apparatus includes main image tone value modification means for modifying a tone value to compress a tone of a main image, first projection means for projecting the main image having the compressed tone by the main image tone value modification part with a first polarization component, sub-image tone value modification means for compressing tones of the sub-image, then modifying tone values of the sub-image by adding to the tone values after the compression an offset value, the offset value being not less than the maximum tone value of the main image having the compressed tone, correction image generation means for generating the correction image formed by subtracting the tone values of the main image having the compressed tone from the tone values modified by the sub-image tone value modification means, and second projection means for projecting the correction image with a second polarization component different from the first polarization component overlaying to the main image project

Abstract: In a method of compensating gamma reference voltages includes setting a plurality of emission signal on-duty ratios that have different values in a range from 0% to 100%, setting a plurality of data offsets for the emission signal on-duty ratios and each of the data offsets being set based on a color shift, the color shift being caused according to the emission signal on-duty ratios, generating a plurality of compensation gamma reference voltages by multiplying a gamma reference voltage by the data offsets, and applying the compensation gamma reference voltages to an organic light emitting display panel in dimming ranges that include the emission signal on-duty ratios, respectively.

Abstract: A special instruction for not encoding a content is incorporated into access authorization data contained in the received signal, so that within a unified system for transmitting and receiving of encoded or non-encoded sound and/or picture contents, it is possible to meet the requirement of public broadcasting and “free-to-air” program providers for a non-encoded processing and/or display and/or storage of freely accessible contents for the end user. The instruction signalizes that the sound and/or picture contents, once received, must be available in the non-encoded form to the end user. The access authorization data remain added to the sound and/or picture contents, even in cases of a cascading, encoded retransmission, or remains logically linked thereto by suitable means, even if transmitted physically separate along with the picture and/or sound contents.

Abstract: A method for data display includes storing an identification code and receiving encoded video content for playback. The encoded video content is decoded so as to output a series of video frames while modulating a background level of the video frames in the series according to the identification code. Related systems and methods are also included.

Abstract: Time-varying CAPTCHA tests are provided to distinguish a human user from a computer software agent in an online application. A test generator generates an original image and a set of (X,Y) positions. The (X,Y) positions can be a random or repeating sequence. The test generator then separates the original image to form a plurality of secondary images. The secondary images are configured to the (X,Y) positions and the original image so that when the secondary images are displaced over time responsive to the (X,Y) positions at least one of the (X,Y) position reveals the original image, or a portion thereof. A test program generator generates an executable program adapted for execution on a client device. The executable program is encoded with the (X,Y) positions and the secondary images, and configured to displace the secondary images over time responsive to the set of positions.

Abstract: Provided is an AV data transmission apparatus including two or more output channels, an encryption unit encrypting AV data using an encryption key, and an AV data transmission unit transmitting the encryption key and the encrypted AV data to AV data reception apparatuses from each output channel. The apparatus also includes an encryption key switching unit switching an encryption key generation scheme to another one for the encryption key transmitted through a selected output channel, an output suspension unit suspending output of the encrypted AV data transmitted through a selected output channel, and a control unit (i) causing the output suspension unit to select an output channel and suspend the output of the encrypted AV data through the selected output channel, and then (ii) causing the encryption key switching unit to select the same output channel and switch the encryption key generation scheme to another one for the output channel.

Abstract: Described herein is a method that includes receiving multiple requests for access to an exposed media object, wherein the exposed media object represents a live media stream that is being generated by a media source. The method also includes receiving data associated with each entity that provided a request, and determining, for each entity, whether the entities that provided the request are authorized to access the media stream based at least in part upon the received data and splitting the media stream into multiple media streams, wherein a number of media streams corresponds to a number of authorized entities. The method also includes automatically applying at least one policy to at least one of the split media streams based at least in part upon the received data.

Abstract: Disclosed is a digital broadcast reception apparatus which performs a scramble judgment by obtaining a judgment PID corresponding to PCR_PID and a judgment packet corresponding to the judgment PID and judging whether the judgment packet is obtained within a first time, subsequently by a value of tsc bit, subsequently by detecting a PES packet where payload starts and judging whether it is detected within a second time, subsequently by detecting packet_start_code_prefix and judging based on the detected value, and subsequently by a value of PES_scrambling_control.

Abstract: An anti-piracy system introduces distortion into a recorded image, while maintaining a high quality projected image. The video source material includes modulated entities for providing artifacts incompatible with the content of the video source material and selectively deliverable information that the projection system uses to demodulate the entities. A projector receives the information about the modulated entity and corrects, or demodulates, the entity. The projection system also imposes a recording device dependent interference on the projected images.

Abstract: A method for processing video content is disclosed. The method comprises: receiving, in a hardware device connected in operation to a computer, encrypted, encoded video content; decrypting the encrypted, encoded video content to form decrypted, encoded video content; decoding a first portion of the decrypted, encoded video content to form a decrypted, decoded video content portion; re-encrypting the decrypted, decoded video content portion to form a re-encrypted, decoded video content portion; re-encrypting a second portion of the decrypted, encoded video content to form a re-encrypted, encoded video content portion; and outputting the re-encrypted, decoded video content portion and the re-encrypted, encoded video content portion to the computer.

Abstract: Methods and apparatus for protecting copyrighted information, e.g., video signals, from unauthorized use are described. Encrypted video signals are transmitted from a source device, e.g., display adapter, to a display device, e.g., monitor, over analog signal lines after the identity of the destination device is confirmed by receipt of a certificate assigned to the destination device. A session key, used for encrypting the analog signals, is generated and exchanged between the source and destination devices. The source and destination devices each include a pseudo-random number generator driven by the session key. As part of the encryption process a false video signal is generated. The false video signal and R, G, B video signals are transmitted to the display device over four lines. The lines used to transmit the R, G, B and false video signals are periodically swapped as a function of the output of the pseudo random number generator to encrypt, e.g., scramble, the video signals.

Abstract: A video system (100) includes a chrominance processing arrangement (200). The chrominance processing arrangement (200) includes a burst accumulator (240) operative to detect a polarity inversion within a burst interval associated with a horizontal line of video information, and generate at least one output signal that compensates for the detected polarity inversion.

Abstract: A method for determining that all of a scrambled message has been successfully received, the scrambled message being scrambled in accordance with a scrambling key and being capable of being descrambled in accordance with a descrambling key, descrambling key generating information for generating the descrambling key being included within a control message (ECM) associated with the scrambled message.

Abstract: An apparatus for embedding secret information in an image signal transmitted with a shape signal showing the shape of an object is described. This apparatus comprises an embedding position decision unit for deciding a position in the object where the secret information is to be embedded, according to the shape signal; and a compositor for embedding the secret information in the position decided by the decision unit. Therefore, the secret information is protected against translation or clipping of image.

Abstract: Systems and methods for tuning channels within a home entertain system by connecting multiple consumer electronics devices to a central electronics device with an internal tuner. The consumer electronics devices are connected in a hub and spoke configuration, with each one being directly connected to the central electronics device. In the hub and spoke configuration, all signals in the home entertainment system are accessible by the central electronics device. Accordingly, the central electronics device can process, route, or otherwise respond to any signal. As such, the central electronics device uses an electronic programming guide (EPG) to differentiate scrambled signals from non-scrambled signals. The scrambled signals are routed to an electronics device, such as a cable box, for descrambling and are sent back to the central electronics device. The non-scrambled signals are tuned by the tuner within the central electronics device.

Abstract: Methods and apparatus for protecting copyrighted information, e.g., video signals, from unauthorized copying. Analog red (R), green (G) and blue (B) video signals are transmitted from a source device, e.g., a display adapter, to a display device, e.g., a monitor, over corresponding analog signal lines after the identify of the destination device is confirmed by receipt of a certificate assigned to the destination device. A session key, used for encrypting the analog signals, is generated and exchanged between the source and destination devices after the identification of the destination device is confirmed. The source and destination devices each includes a pseudo-random number generator driven by the session key. The lines that carry the R, G and B video signals are changed, e.g., swapped, on a periodic basis as a function of the output of the pseudo-random number generator in the source device.

Abstract: An image altering apparatus which provides confidential viewing of a video display by means of time multiplexing the fundamental display image with a color-inverted image thereof on a pixel-by-pixel basis. Electronic circuitry and/or software are utilized to modify the fundamental image signal by time multiplexing its color data components with corresponding inverse color data components to generate a compound image signal which is representative of a substantially featureless image. Different multiplexing sequences of color data components and inverse color data components may be utilized at varying duty cycles to generate a compound image which is highly confidential and secure from unauthorized viewing.

Abstract: This invention discloses a method of protecting copyright of a digital video work by using a digital password technology and a digital watermark technology to prevent the unauthorized use of a digital video work. Such method adds password protection of two chrominance arrays of such video work in advance, so that when such video work is published on the Internet, it can only be played in color by a specified player. As long as a user enters the correct password into the specified player, a full color visual effect of such video work can be obtained. If other players are used to play such video work, only a partial gray-scale visual effect can be obtained. Users must request or buy a specific player and a password from the distributor of such video work to play the complete information to prevent piracy.

Abstract: The present invention is directed towards providing a partial dual-encrypted stream in a conditional access overlay system. The headend equipment includes an aligner, identifier, and remapper (AIR) device (615) that receives a clear stream and one or two encrypted streams, where the two encrypted streams have been encrypted by two different encryption schemes. The AIR device (615) identifies critical packets associated with the clear stream and subsequently allows two encrypted streams to pass and drops the critical packets of the clear stream. A multiplexer (640) then combines a percentage of the non-critical packets of the clear stream and the critical packets of the two encrypted streams to provide the partial dual-encrypted stream.

Abstract: A method and an apparatus for error resilient, digital image scrambling are disclosed. Error resilience scrambling is produced by shuffling transform coefficients between arrays of coefficients arranged along an axis substantially orthogonal to the axis along which packetization of the coefficients proceeds. Scrambling transform coefficients requires a reasonable level of processing resources and has minimal impact on the efficiency of the compression process. Shuffling can be performed in a number of ways to provide good access security and a variety of security. Scrambling the image data in a direction substantially orthogonal to the direction of packetization of the transform coefficients distributes any transmission error in the image reducing the effects of data error or loss on the displayed image.

Abstract: An image processing apparatus for encrypting a profile for color matching, generates a table which stores change information of the profile, changes data in the profile on the basis of the generated table, and encrypts the table by a predetermined algorithm.

Abstract: A device and method thereof for packetizing scalably encoded data. The device can include a receiver adapted to receive a stream of data from an encoding device, wherein at least a first portion of the data is scalably encoded. The device can also include a packetizer coupled to the receiver, the packetizer adapted to packetize at least a second portion of the data into scalable data packets.

Abstract: Visible watermarking techniques for digital images and video operate on decoded transform coefficients and maintain the watermarked data in the same compressed format as the original so that the watermarked data can be viewed with standard tools and applications. Moreover, for most of the techniques presented, the watermarked data has exactly the same compressed size as the original. The watermark can be inserted and removed using a key for applications requiring content protection. The watermark insertion and removal algorithms are very efficient and exploit some features of compressed data formats (such as JPEG and MPEG) which allow most of the work to be done in the compressed domain.

Abstract: An image display apparatus and method is disclosed that can prevent shot-sneaking of an image displayed by a projector apparatus. The projector apparatus embeds a display image portion in which the same color is represented with another color space of R, Cy, and B by color space conversion as a shot-sneaking preventing image portion into an original image as a display image for which a color space of R, G, and B is used to reproduce a color. The shot-sneaking preventing image portion appears to the visual sense of the human being as the same color as that of the oringinal image. However, the color component values of R and B are different in terms of the color component values of R and B between the color space of R, G, and B and the color space of R, Cy, and B. Therefore, for example, if a camera that picks up an image in accordance with the R, G, B method is used to pick up an image of the display image, then the picked-up display image is reproduced in a color different from the original color.

Abstract: Methods and apparatus for protecting copyrighted information, e.g., video signals, from unauthorized use are described. Encrypted video signals are transmitted from a source device, e.g., display adapter, to a display device, e.g., monitor, over analog signal lines after the identity of the destination device is confirmed by receipt of a certificate assigned to the destination device. A session key, used for encrypting the analog signals, is generated and exchanged between the source and destination devices. The source and destination devices each include a pseudo-random number generator driven by the session key. As part of the encryption process a false video signal is generated. The false video signal and R, G, B video signals are transmitted to the display device over four lines. The lines used to transmit the R, G, B and false video signals are periodically swapped as a function of the output of the pseudo random number generator to encrypt, e.g., scramble, the video signals.

Abstract: Methods and apparatus for protecting copyrighted information, e.g., video signals, from unauthorized coping. Analog red (R), green (G) and blue (B) video signals are transmitted from a source device, e.g., a display adapter, to a display device, e.g., a monitor, over corresponding analog signal lines after the identify of the destination device is confirmed by receipt of a certificate assigned to the destination device. A session key, used for encrypting the analog signals, is generated and exchanged between the source and destination devices after the identification of the destination device is confirmed. The source and destination devices each includes a pseudo-random number generator driven by the session key. The lines that carry the R, G and S video signals are changed, e.g., swapped, on a periodic basis as a function of the output of the pseudo-random number generator in the source device.

Abstract: A system controls reproduction of a video transmission between a transmitter and a receiver. The system includes an encryptor with an offset generator adapted to receive the encrypted frame key and to generate a sequence of pseudo-random values for the color component; and an adder coupled to the offset generator and to the color component signal for providing an encoded color component signal. The system also includes a decryptor with a decryptor offset generator adapted to receive the encrypted frame key and to generate a decryptor pseudo-random value for the color component; and a subtractor coupled to the offset generator and to the color component signal for subtracting the offset signal from the color component signal.

Abstract: A system (300, 500) for scrambling digital samples (115, 200, 250, 260, 270) of multimedia data, including audio and video data samples, such that the content of the samples is degraded but still recognizable, or otherwise provided at a desired quality level. The samples may be in any conceivable compressed or uncompressed digital format, including Pulse Code Modulation (PCM) samples, samples in floating point representation, samples in companding schemes (e.g., ?-law and A-law), and other compressed bit streams. The quality level may be associated with a particular signal to noise ratio, or quality level that is determined by objective and/or subjective tests, for example. A number of LSBs can be scrambled in successive samples in successive frames (FRAME A, FRAME B, FRAME C). Moreover, the parameters for scrambling may change from frame to frame. Furthermore, all or part of the scrambling key (310) can be embedded (340) in the scrambled data and recovered at a decoder (400, 600) to be used in descrambling.

Abstract: An encryption device includes a card with a grid comprising multiple rows and columns defining boxes for receiving individual characters. One of the columns or rows contains a master password or code character string. Other columns or rows contain encrypted character strings. The individual characters of the master password can be offset with respect to corresponding, individual characters of the encrypted character strings. A sleeve slidably, reciprocably receives the card and assists with aligning the characters of the master password and the characters of the encrypted character strings, which are visible through a window in the sleeve. A method of storing, encrypting and retrieving character strings utilizes the encryption device.

Abstract: Digital video data is encryptically processed and then subjected to an encoding procedure with orthogonal transform to produce a coded video signal. A representative value of luminance of pixels of the digital video data is obtained for each of pixel blocks having a predetermined number of pixels, each pixel block corresponding to a unit of data subjected to the encoding procedure, as a quantized integer for each pixel block by using a specific function with the stored luminance data as a parameter. It is determined whether the quantized integer of the representative value for each pixel block is a multiple of a preset integer N of two or larger, and, if not, the stored luminance data are rewritten with a specific requirement giving the least range of change in gradation so that the quantized integer becomes a multiple of the integer N, whereas the stored luminance data remain unchanged if the quantized integer is a multiple of the integer N, thus the digital video data being encryptically processed.

Abstract: An image processing apparatus for encrypting a profile for color matching, generates a table which stores change information of the profile, changes data in the profile on the basis of the generated table, and encrypts the table by a predetermined algorithm.

Abstract: In step S904, color signals which form input image data are converted into device-independent color signals (color signals X, Y, and Z) using an input profile. In step S905, the color signals X, Y, and Z are converted into color signals Re, Ge, and Be that form encrypted image data using an encryption profile.

Abstract: A system controls reproduction of a video transmission between a transmitter and a receiver. The system includes an encryptor with an offset generator adapted to receive the encrypted frame key and to generate a sequence of pseudo-random values for the color component; and an adder coupled to the offset generator and to the color component signal for providing an encoded color component signal. The system also includes a decryptor with a decryptor offset generator adapted to receive the encrypted frame key and to generate a decryptor pseudo-random value for the color component; and a subtractor coupled to the offset generator and to the color component signal for subtracting the offset signal from the color component signal.

Abstract: Disclosed is an apparatus and method for descrambling transport stream (TS) data, the descrambling apparatus including: a TS packet input unit for determining from the value of a header of TS packet data whether the TS packet data are scrambled, and outputting determination results and the TS packet data; a descramble controller for applying a control signal to the TS packet input unit for the TS packet input unit to read the TS packet data, and outputting a scramble determination signal of a corresponding state based on the determination results; and a descrambler for determining from the state of the scramble determination signal whether the TS packet data from the TS packet input unit are scrambled, and determining whether to descramble the TS packet data.

Abstract: An image altering apparatus which provides confidential viewing of a video display by means of time multiplexing the fundamental display image with a color-inverted image thereof on a pixel-by-pixel basis. Electronic circuitry and/or software are utilized to modify the fundamental image signal by time multiplexing its color data components with corresponding inverse color data components to generate a compound image signal which is representative of a substantially featureless image. Different multiplexing sequences of color data components and inverse color data components may be utilized at varying duty cycles to generate a compound image which is highly confidential and secure from unauthorized viewing.

Abstract: A video system (100) includes a chrominance processing arrangement (200). The chrominance processing arrangement (200) includes a burst accumulator (240) operative to detect a polarity inversion within a burst interval associated with a horizontal line of video information, and generate at least one output signal that compensates for the detected polarity inversion.

Abstract: A system controls reproduction of a video transmission between a transmitter and a receiver. The system includes an encryptor with an offset generator adapted to receive the encrypted frame key and to generate a sequence, of pseudo-random values for the color component; and an adder coupled to the offset generator and to the color component signal for providing an encoded color component signal. The system also includes a decryptor with a decryptor offset generator adapted to receive the encrypted frame key and to generate a decryptor pseudo-random value for the color component; and a subtractor coupled to the offset generator and to the color component signal for subtracting the offset signal from the color component signal.

Abstract: An improved television scrambling signal is achieved by adding erroneous clamp pulses into a television signal after the signal may have been previously scrambled, for example, by prior art position modulated horizontal sync pulses. Prior art scrambling systems such as those using position modulated sync pulses cause tearing in an unauthorized displayed television picture. The addition of the erroneous clamp pulses of the present invention causes both tearing and darkening of the picture. This darkening can completely shut off the display on some TV sets, thus yielding complete concealment of the television signal. In an alternative embodiment, an erroneous color “rainbow” effect is provided by modifying a portion of a color burst signal, to cause the color subcarrier system in a TV set to unlock.

Abstract: During a period of a burst signal that controls a color in a video signal, a signal having the reverse phase and double the amplitude of the burst signal is added to superpose the signal on the burst signal by less than some cycles of the burst signal. A processed burst signal thus made is recorded on the magnetic tape. And, when reproducing the magnetic tape, a color signal detection circuit of a TV monitor is not influenced to reproduce a normal picture image. And, the color signal detection circuit of a video tape recorder is influenced to malfunction, which prevents a correct recording. To reproduce a magnetic tape duplicated by the video tape recorder by the TV monitor will present an abnormal picture image. Thus, the invention intends to prevent an unfair duplication, by making the color of the picture image abnormal in the unfair duplication.

Abstract: In certain video scrambling systems, composite video is imperfectly separated into luminance and chrominance and scrambled in such a way that an unstable residual chroma color subcarrier remains in the luminance channel. When this unstable residual subcarrier subsequently is summed with stabilized chroma, the resultant composite color signal has small but visible amounts of color subcarrier instability that causes a noisy color signal when descrambled or when displayed on a television display device. A coring circuit is disclosed which provides means for substantially removing the unstable residual chroma subcarrier from the luminance channel, thereby substantially reducing color subcarrier instabilities. An improved coring technique also is disclosed using adaptive chroma coring, which is achieved by adjusting the amount of coring applied in accordance with the amplitude of the chrominance signal.

Abstract: A video signal copy guard system in which a special color burst signal (or “copy prohibition signal”) is inserted into the video signal to be copy protected so that the protected signal includes both a special color burst signal and a normal color burst signal. The special color burst signal is placed adjacent to the normal color burst signal, and its phase, frequency, and/or amplitude is varied with respect to the normal color burst signal. The special color burst signal interferes with the normal color burst signal when an analog VCR attempts to process the protected signal. Thereby, preventing unauthorized dubbing of the protected signal.

Abstract: A video signal processing apparatus, a video signal processing method and a recording medium are provided for reliably preventing illegal copy through a VTR and supplying a high-quality video signal with a copyright protecting function without interfering with an image displayed on a TV set. A color burst signal generating unit and a signal selector are controlled by a timing generator in a color stripe sequence. The color burst signal generating unit is controlled to output at least two of a U-axis inverted burst signal UI produced by inverting a U-axis component of a burst phase, a V-axis inverted burst signal VI produced by inverting a V-axis component of the burst phase, and a both-axes inverted burst signal I produced by inverting the U-axis/V-axis as a color stripe signal with a copyguard function. Then, the signal selector operates to add the color stripe signal to color difference signals U and V as a copyguard signal in place of a normal color burst signal.

Abstract: A technique is disclosed for preventing unauthorized playback of scrambled video/audio signals recorded on, for example, a video tape cassette, which technique includes several cooperating processes and apparatus which further prevent the playback of recorded video/audio when the playback apparatus is in a still or pause mode of operation. The technique includes selected combinations of processes of inverting and re-clamping the luminance component of the video signal just prior to FM modulation; blanking an overscan portion, or portions, of the video signal and adding a video retrace signal to the overscan portion(s); inverting the normal control track signal and position modulating the normally unused edge; and selectively scrambling the audio signal and recording the scrambled audio signal in an audio track or in a Hi-Fi track. A selected user specific authorization code is recording in and recovered from the audio track.