摘要:
Techniques are presented herein to provide tandem-free operation between two wireless terminals through two otherwise incompatible wireless networks. Specifically, embodiments provide tandem-free operation between a wireless terminal communicating through a continuous transmission (CTX) wireless channel to a wireless terminal communicating through a discontinuous transmission (DTX) wireless channel. In a first aspect, inactive speech frames are translated between DTX and CTX formats. In a second aspect, each wireless terminal includes an active speech decoder that is compatible with the active speech encoder on the opposite end of the mobile-to-mobile connection.
摘要:
The disclosure is directed to techniques for region-of-interest (ROI) coding for video telephony (VT). The disclosed techniques include a technique for generation of a quality metric for ROI video, which jointly considers a user's degree of interest in the ROI, ROI video fidelity, and ROI perceptual quality in evaluating the quality of an encoded video sequence. The quality metric may be used to bias ROI coding and, in particular, the allocation of coding bits between ROI and non-ROI areas of a video frame.
摘要:
The disclosure is directed to techniques for content-adaptive background skipping for region-of-interest (ROI) video coding. The techniques may be useful in video telephony (VT) applications such as video streaming and videoconferencing, and especially useful in low bit-rate wireless communication applications, such as mobile VT. The disclosed techniques analyze content information of a video frame to dynamically determine whether to skip a non-ROI area within the frame. For example, the skipping determination may be based on content activity, such as ROI shape deformation, ROI motion, non-ROI motion, non-ROI texture complexity, and accumulated distortion due to non-ROI skipping. The skip determination may operate in conjunction with either frame-level or macroblock-level bit allocation.
摘要:
The disclosure is directed to adaptive frame skipping techniques for rate controlled video encoding of a video sequence. According to the disclosed techniques, an encoder performs frame skipping in an intelligent manner that can improve video quality of the encoded sequence relative to encoding using conventional frame skipping. In particular, the disclosed frame skipping scheme is adaptive and considers motion activity of the video frames in order to identify certain frames that can be skipped without sacrificing significant video quality. The described frame skipping techniques may take into account the tradeoff between spatial and temporal quality of different video frames. In this manner, the techniques can allocate limited resources between the spatial and temporal quality in a way that can improve the visual appearance of a video sequence.
摘要:
The disclosure is directed to a video slicing technique that promotes low complexity, bandwidth efficiency and error resiliency. A video encoder places an RM close to the beginning of each logical transmission unit (LTU) so that all but a very small end segment of each video slice fits substantially within an LTU. Instead of requiring placement of RMs exactly at the LTU boundaries, a video encoder applies an approximate alignment technique. Video slices are encoded so that RMs are placed close to the beginning of each LTU, e.g., at the end of the first MB falling within the LTU. A portion of the last MB from the preceding slice carries over into the next LTU. Loss of an LTU results in loss of virtually the entire current slice plus a very small portion of the previous slice.
摘要:
A system and method for detection of rate determination algorithm errors in variable rate communications system receivers. The disclosed embodiments prevent rate determination algorithm errors from causing audible artifacts such as screeches or beeps. The disclosed system and method detects frames with incorrectly determined data rates and performs frame erasure processing and/or memory state clean up to prevent propagation of distortion across multiple frames. Frames with incorrectly determined data rates are detected by checking illegal rate transitions, reserved bits, validating unused filter type bit combinations and analyzing relationships between fixed code-book gains and linear prediction coefficient gains.
摘要:
Configurations disclosed herein include systems, methods and apparatus that may be applied in a voice communications and/or storage application to remove, enhance, and/or replace the existing context. Example embodiments may first remove any existing context from a digital audio signal to obtain a context suppressed signal. The context suppressed signal may then be encoded. An audio context may be selected from among a plurality of audio contexts, with the selected audio context inserted into a signal based on the encoded context suppressed signal.
摘要:
Configurations disclosed herein include systems, methods, and apparatus that may be applied in a voice communications and/or storage application to remove, enhance, and/or replace the existing context. Particularly, certain embodiments contemplate suppressing the context component from the digital audio signal to obtain a context-suppressed signal; generating an audio context signal that is based on a first filter and a first plurality of sequences, each of the first plurality of sequences having a different time resolution and mixing a first signal that is based on the generated audio context signal with a second signal that is based on the context-suppressed signal to obtain a context-enhanced signal, wherein generating an audio context signal includes applying the first filter to each of the first plurality of sequences.
摘要:
Configurations disclosed herein include systems, methods, and apparatus that may be applied in a voice communications and/or storage application to remove, enhance, and/or replace the existing context. In one aspect, a method of processing a digital audio signal that includes a first audio context is disclosed. The method comprises based on a first audio signal that is produced by a first microphone, suppressing the first audio context from the digital audio signal to obtain a context-suppressed signal. The method may further comprise selecting a second context based on the first audio context, and mixing the second audio context with a signal that is based on the context-suppressed signal to obtain a context-enhanced signal.
摘要:
A video demultiplexer and video decoder include features for efficient video data recovery in the event of channel error. The demultiplexer detects a boundary between physical layer data units and adds boundary information to the bitstream produced by the demultiplexer. The demultiplexer produces adaptation layer data units, which are processed by the adaptation layer to produce an application layer bitstream. When the video decoder encounters an error in the bitstream, it uses the boundary information to limit the amount of data that must be concealed. In particular, the boundary information permits the error to be associated with a small segment of data. The video decoder conceals data from the beginning of the segment of data, rather than an entire slice or frame in which the segment resides. In this manner, the video decoder provides efficient data recovery, limiting the loss of useful data that otherwise would be purposely discarded for concealment purposes.