摘要:
An embodiment of an apparatus to authenticate a sequence of video frames includes a process to choose intra-frames of the sequence and sample DC components thereof to produce a set of test fingerprints. To reduce a dimensionality of the test fingerprints, the DC components of the chosen intra-frames are multiplied by a projection matrix formed of eigenvectors associated with the larger eigenvalues of a covariance matrix for a library of frames. The projected test fingerprints are compared against a reference set of fingerprints for authentication. Time-stamp spacings of the chosen intra-frames are determined, and these spacings are employed to select candidate frames for authentication in the reference set of fingerprints.
摘要:
Embodiments of the invention generally include multi-component catalyst systems, polymerization processes and heterophasic copolymers formed by the processes. The multi-component catalyst system generally includes a first catalyst component selected from Ziegler-Natta catalyst systems including a diether internal electron donor and a metallocene catalyst represented by the general formula XCpACpBMAn, wherein X is a structural bridge, CpA and CpB each denote a cyclopentadienyl group or derivatives thereof, each being the same or different and which may be either substituted or unsubstituted, M is a transition metal and A is an alkyl, hydrocarbyl or halogen group and n is an integer between 0 and 4. The multi-component catalyst system further includes a second catalyst component generally represented by the formula XCpACpBMAn, wherein X is a structural bridge, CpA and CpB each denote a cyclopentadienyl group or derivatives thereof, each being the same or different and which may be either substituted or unsubstituted, M is a transition metal and A is an alkyl, hydrocarbyl or halogen group and n is an integer between 0 and 4 and wherein the second catalyst component exhibits a higher ethylene response than the first catalyst component.
摘要:
Gas hydrate formation in a well completion fluid in the annular space of a hydrocarbon producing well may be controlled by the incorporation of effective amounts of one or more low dose gas hydrate inhibitors, including but not limited to, low dosage hydrate inhibitors (LDHIs), kinetic hydrate inhibitors, dendrimeric or branched compounds, linear polymers and copolymers, grafted or branched linear polymers and copolymers, and onium compounds.
摘要:
The disclosure describes methods for using digital watermarking to authenticate digital media signals, such as images, audio and video signals. It also describes techniques for using embedded watermarks to repair altered parts of a media signal when alteration is detected. Alteration is detected using hashes, digital watermarks, and a combination of hashes and digital watermarks.
摘要:
Described are methods and devices for automatically coupling two or more mobile communication devices (502, 541) to share content such as calls, music, documents, video and games where two or more devices automatically determine the feasibility of sharing the content and negotiate to find an efficient manner in which to do so. In this way, the pairing between devices may be transparent to the users. Moreover, a better choice in a transport may be selected without user input. Each device may include a near field communication (NFC) device that when in range of the other device may automatically initiate pairing between the devices so that the devices may share content. The users of NFC enabled devices may have little or minimal interactions except that one or more users may bring the devices within range so that the NFCs may initiate the pairing between the devices.
摘要:
Systems and methods for communication systems with compressive sensing are disclosed. In one embodiment, a method of signal processing includes receiving a data packet at a processor. The data packet includes compressively measured data in wavelet transform coefficients of a signal. The signal is reconstructed using a clustering property of the wavelet transform coefficients.
摘要:
A method to establish a full-duplex audio connection over an asynchronous Bluetooth link between an audio terminal and a wireless audio device exchanges supported service classes and codecs between the audio terminal and the wireless audio device, negotiates a service class and a codec that are common to the audio terminal and the wireless audio device, and establishes an asynchronous audio connection between the audio terminal and the wireless audio device using the common service class and the codec. The audio connection established can depend on the software application desiring the audio connection plus the available service classes and codecs at the audio terminal and wireless audio device. For non-internet protocol (non-IP) audio applications, an ACL using AVDTP may be selected; for IP audio applications, an ACL using BNEP may be selected. Both AVDTP and BNEP can use codecs that support wide bandwidth audio.