Feed Back Patents (Class 375/240.05)
  • Patent number: 7933294
    Abstract: Systems and methods for communication of scaleable-coded audiovisual signals over multiple TCP/IP connections are provided. The sender schedules and prioritizes transmission of individual scalable-coded data packets over the plurality of TCP connections according to their relative importance in the scalable coding structure for signal reconstruction quality and according to receiver feedback. Low-latency packet delivery over the multiple TCP/IP connections is maintained by avoiding transmission or retransmission of packets that are less important for reconstructed media quality.
    Type: Grant
    Filed: December 10, 2007
    Date of Patent: April 26, 2011
    Assignee: Vidyo, Inc.
    Inventors: Jacob Chakareski, Roi Sasson, Alexandros Eleftheriadis, Ofer Shapiro
  • Patent number: 7912123
    Abstract: The present invention discloses a simple low cost framework for robust operational control of video encoders. The framework comprises a two-layer architecture that effectively decouples the processes of video bit rate control and video quality/distortion control. The upper layer includes a video bit rate controller that operates on a single picture/picture-slice, or a set of pictures/picture-slices, and is based on feedback control techniques used in automatic control systems. The lower layer includes a video quality/distortion controller that operates at the level of blocks of pixels, and reduces distortion artifacts. The decoupled nature of the encoder control architecture of the present invention provides the flexibility of combining various feedback control algorithms and various distortion reduction schemes.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: March 22, 2011
    Assignee: Streaming Networks (Pvt.) Ltd
    Inventors: Syed Muhammad Ziauddin, Imran ul-Haq, Muhammad Nadeem, Muhammad Shafique
  • Patent number: 7894820
    Abstract: Embodiments of methods and apparatus for providing channel feedback information based at least in part on predicted future channel states is disclosed and described. In various embodiments, future channel states may be predicted based at least in part on received channel sounding signals, and amounts of delay in time in transmission and receipt between a subscriber station and a base station. Other embodiments may be described and claimed.
    Type: Grant
    Filed: December 28, 2006
    Date of Patent: February 22, 2011
    Assignee: Intel Corporation
    Inventors: Qinghua Li, Xintian E. Lin
  • Patent number: 7894523
    Abstract: A method for context-modeling coding information of a video signal for compressing or decompressing the coding information is provided. An initial value of a function for probability coding of coding information of a video signal of an enhanced layer is determined based on coding information of a video signal of a base layer.
    Type: Grant
    Filed: July 10, 2006
    Date of Patent: February 22, 2011
    Assignee: LG Electronics Inc.
    Inventors: Byeong Moon Jeon, Doe Hyun Yoon, Ji Ho Park, Seung Wook Park
  • Publication number: 20110013693
    Abstract: A video encoding apparatus and a corresponding method for applying orthogonal transformation to a prediction error signal between a video signal of an encoding target area and a predicted signal for the video signal, and quantizing an obtained orthogonal transformation coefficient by using a preset quantization step size so as to encode the coefficient. A prediction error power which is a power of the prediction error signal is computed. For input information such as the computed prediction error power, the preset quantization step size, and an upper limit of an amount of code generated for the encoding target area, it is determined whether or not an amount of code generated when performing quantization using the preset quantization step size exceeds the upper limit. An encoding process is changed based on a result of the determination.
    Type: Application
    Filed: July 10, 2008
    Publication date: January 20, 2011
    Inventors: Atsushi Shimizu, Yasuyuki Nakajima
  • Patent number: 7873105
    Abstract: Presented herein are optimized single inverse quantization engines for a plurality of standards. In one embodiment, there is presented a system for inverse quantizing quantized frequency coefficients. The system comprises an inverse quantizer for inverse quantizing video data encoded in accordance with a first encoding standard and for inverse quantizing video data encoded in accordance with a second encoding standard. In another embodiment, there is presented a decoder for decoding video data. The decoder comprises an inverse quantizer operable to inverse quantize video data encoded in accordance with a first encoding standard and for inverse quantizing video data encoded in accordance with a second encoding standard.
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: January 18, 2011
    Assignee: Broadcom Corporation
    Inventors: Bhaskar Sherigar, Anand Tongle
  • Patent number: 7860159
    Abstract: A quantization matrix used in inverse quantization is generated. A received bitstream includes a coded truncated quantization matrix. The coded truncated quantization matrix has first coded bits and second coded bits. The first coded bits include bits obtained by coding a transmitting part of quantization elements and the second coded bits includes bits obtained by coding an end code. The coded truncated quantization matrix is decoded until the second coded bits corresponding to the end code are read out, to obtain the transmitting part of quantization elements. At least one additional quantization element is obtained. A complete quantization matrix is generated, using the transmitting part of quantization elements and at least one additional quantization element, by ordering the transmitting part of quantization elements and at least one additional quantization element in a zig-zag scan.
    Type: Grant
    Filed: November 25, 2005
    Date of Patent: December 28, 2010
    Assignee: Panasonic Corporation
    Inventors: Sheng Mei Shen, Thiow Keng Tan
  • Patent number: 7826533
    Abstract: A method for object edge detection in a macroblock and a method for deciding quantization scaling factor are disclosed. This method calculates and compares the pixel means and means of absolutely difference of a plurality of pixel blocks in a macroblock to achieve the purpose of detecting if there is an object edge or flat area in a macroblock. In the meantime, the image structure of macroblock is analyzed and classified and its related messages are used for bit rate control, such that the visual effect of the compressed image can be appropriately enhanced.
    Type: Grant
    Filed: July 22, 2005
    Date of Patent: November 2, 2010
    Assignee: Sunplus Technology Co., Ltd.
    Inventors: Pai-Chu Hsieh, Tzu-Hsin Wang, Chien-Yu Lin
  • Patent number: 7822118
    Abstract: A Method And Apparatus For Control of Rate-Distortion Tradeoff by Mode Selection in Video Encoders is Disclosed. The system of the present invention first selects a distortion value D near a desired distortion value. Next, the system determines a quantizer value Q using the selected distortion value D. The system then calculates a Lagrange multiplier lambda using the quantizer value Q. Using the selected Lagrange multiplier lambda and quantizer value Q, the system begins encoding pixelblocks. If the system detects a potential buffer overflow, then the system will increase the Lagrange multiplier lambda. If the Lagrange multiplier lambda exceeds a maximum lambda threshold then the system will increase the quantizer value Q. If the system detects a potential buffer underflow, then the system will decrease the Lagrange multiplier lambda. If the Lagrange multiplier lambda falls below a minimum lambda threshold then the system will decrease the quantizer value Q.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: October 26, 2010
    Assignee: Apple Inc.
    Inventors: Barin Geoffry Haskell, Adriana Dumitras, Atul Puri
  • Patent number: 7792385
    Abstract: A video processing apparatus and methodology are implemented as a combination of a processor and a video decoding hardware block to decode video data by providing the video decoding block with an in-loop filter and a scratch pad memory, so that the in-loop filter may efficiently perform piecewise processing of overlap smoothing and in-loop deblocking in a macroblock-based fashion which is a much more efficient algorithm than the frame-based method.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: September 7, 2010
    Assignee: GlobalFoundries Inc.
    Inventors: Bill Kwan, Erik Schlanger, Raquel Rozas, Casey King
  • Patent number: 7792193
    Abstract: An image encoding method includes generating a predictive signal and encoding mode information according to each encoding mode from a macroblock signal corresponding to each macroblock, selecting a quantization code table corresponding to each macroblock, generating a predictive error signal for each encoding mode based on the macroblock signal and the predictive signal, subjecting the predictive error signal to orthogonal transformation, quantizing the orthogonal-transformed predictive error signal while changing a quantization parameter for every plural sub-pixel-blocks, using the quantization code table corresponding to the macroblock, encoding quantization transformation coefficient, calculating an encoding cost, selecting one encoding mode based on the encoding cost, selecting one quantization code table based on the encoding cost, and encoding information of an index indicating the selected quantization code table for every frame of the input image signal or every region of the frame.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: September 7, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akiyuki Tanizawa, Takeshi Chujo
  • Patent number: 7787746
    Abstract: The invention concerns a method (200) and system (100) performing a trick mode on a video signal containing a plurality of original pictures. The method includes the steps of selectively skipping (214) at least one of the original pictures to convert the video signal to a trick mode video signal in response to a trick mode command and selectively inserting (224) at least one dummy bidirectional predictive picture in the trick mode video signal using field-based prediction. The method can also include the steps of monitoring (220) the trick mode video signal in which the step of selectively inserting at least one dummy bidirectional predictive picture in the trick mode video signal can be done if the bit rate of the trick mode video signal exceeds a predetermined threshold.
    Type: Grant
    Filed: June 13, 2002
    Date of Patent: August 31, 2010
    Assignee: Thomson Licensing
    Inventors: Shu Lin, Donald Henry Willis
  • Patent number: 7782940
    Abstract: Disclosed herein in one embodiment is an adaptive coding threshold algorithm for a videoconference system which alleviates problems due to the erroneous recoding of stationary areas of images caused by image noise. The algorithm, which is preferably implementable on a videoconference encoder, assesses the coding parameters for a current macroblock and the coding parameters for that same macroblock the last time it was coded. If for both macroblocks the coding was non-intra, with a [0,0] motion vector, and with a low quantization parameter, a determination is made that the current macroblock depicts a stationary image. Accordingly, the algorithm increases the coding threshold (T1) for the blocks within that macroblock, so that it becomes more difficult for those particular blocks to be recoded. This renders the block with stationary content less susceptible to erroneous recoding, while preserving system bandwidth and improving image quality.
    Type: Grant
    Filed: August 1, 2003
    Date of Patent: August 24, 2010
    Assignee: Polycom, Inc.
    Inventors: Mohammad Athar Shah, Michael J. Horowitz
  • Patent number: 7769084
    Abstract: Method For Implementing A Quantizer In A Multimedia Compression And Encoding System is disclosed. In the Quantizer system of the present invention, several new quantization ideas are disclosed. In one embodiment, adjacent macroblocks are grouped together into macroblock groups. The macroblock groups are then assigned a common quantizer value. The common quantizer value may be selected based upon how the macroblocks are encoded, the type of macroblocks within the macroblock group (intra-blocks or inter-blocks), the history of the motion vectors associated with the macroblocks in the macroblock group, the residuals of the macroblocks in the macroblock group, and the energy of the macroblocks in the macroblock group. The quantizer value may be adjusted in a manner that is dependent on the current quantizer value. Specifically, if the quantizer value is at the low end of the quantizer scale, then only small adjustments are made.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: August 3, 2010
    Assignee: Apple Inc.
    Inventors: Thomas Pun, Roger Kumar, Xiaochun Nie, Hsi-Jung Wu
  • Publication number: 20100166062
    Abstract: A computer-implemented system and method for performing video compression are described.
    Type: Application
    Filed: August 7, 2009
    Publication date: July 1, 2010
    Inventors: Stephen G. Perlman, Roger van der Laan, Timothy Cotter, Scott Furman, Robert McCool, Ian Buckley
  • Patent number: 7738555
    Abstract: A quantizer and dequantizer for use in a video coding system that applies non linear, piece-wise linear scaling functions to video information signals based on a value of a variable quantization parameter. The quantizer and dequantizer apply different non linear, piece-wise linear scaling functions to a DC luminance signal, a DC chrominance signal and an AC chrominance signal. A code for reporting updates of the value of the quantization parameter is interpreted to require larger changes when the quantization parameter initially is large and smaller changes when the quantization parameter initially is small.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: June 15, 2010
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Barin Geoffry Haskell, Atul Puri, Robert Lewis Schmidt
  • Patent number: 7733955
    Abstract: An image information decoding method for decoding compressed image information which has been coded via a process including dividing an input image signal into blocks, performing an orthogonal transform on the blocks on a block-by-block basis, and quantizing resultant orthogonal transform coefficients. The decoding process includes performing dequantization such that a quantization parameter is weighted by an addition operation, and the dequantization is performed on each chroma components of the quantized coefficients using said weighted quantization parameter, and performing an inverse orthogonal transform.
    Type: Grant
    Filed: August 9, 2007
    Date of Patent: June 8, 2010
    Assignee: Sony Corporation
    Inventors: Kazushi Sato, Osamu Sunohara, Teruhiko Suzuki, Peter Kuhn, Yoichi Yagasaki, Kuniaki Takahashi
  • Patent number: 7697608
    Abstract: A scaleable macro block rate control method particularly well-suited for MPEG video. There is provided a method to easily derive a quantization parameter (QP) value using information such as bit usage, previous QP values and SAD values from the past encoded and future frames. The method utilizes quantization estimation techniques based on statistical relationships between different intensity measures, such as distortion intensity, absolute difference intensity and mean of absolute difference intensity. The method is well-suited to applications utilizing MPEG video such as MPEG-1, MPEG-2, MPEG-4, JVT/H.264 standards and so forth.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: April 13, 2010
    Assignees: Sony Corporation, Sony Electronics, Inc.
    Inventor: Hung-Ju Lee
  • Patent number: 7675970
    Abstract: A method and apparatus for processing a bitstream in a digital video transcoder is described. In one example, an adjustment factor is determined that relates a number of bits representing a selected frame defined by the bitstream to a target number of bits for the selected frame. An average spatial activity value among sets of video data is associated with the selected frame. A spatial activity value for a selected set of the sets of video data is determined. A normalized spatial, activity value for the selected set of frequency video data is then computed in response to the average spatial activity value, the spatial activity value, and a function of the adjustment factor. Target bit reduction for each of the sets of video data may be computed using a function of the normalized spatial activity value and the adjustment factor.
    Type: Grant
    Filed: January 12, 2004
    Date of Patent: March 9, 2010
    Assignee: General Instrument Corporation
    Inventors: Robert S. Nemiroff, Siu-Wai Wu
  • Patent number: 7653128
    Abstract: An information processing apparatus for decoding compression-coded video data includes at least one decoder decoding the compression-coded video data, a supply controller controlling the supply of the compression-coded video data to the decoder, and a controller controlling processing executed by the supply controller and the decoder. The controller determines the order of decoding processing performed by the decoder so that, among pictures contained in a decoding processing unit for the decoding processing performed by the decoder, I-pictures and P-pictures are decoded before B-pictures. The controller selects pictures to be output from the decoder from among the pictures contained in the decoding processing unit on the basis of a playback speed instruction provided by a playback speed instruction unit.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: January 26, 2010
    Assignee: Sony Corporation
    Inventors: Shojiro Shibata, Shuji Tsunashima, Kyohei Koyabu, Mototsugu Takamura, Shinjiro Kakita, Mitsuhisa Kaneko
  • Publication number: 20100014583
    Abstract: A quantization control method used in a video encoding which encodes a video image and performs control for making an encoding bit rate approach a predetermined target bit rate. The quantization control method includes measuring a differential amount of code between a target amount of code and an amount of generated code; determining whether or not a predetermined condition has occurred; determining, when it is determined that the condition has occurred, a variation for an amount of feedback which increases or decreases a quantization step size, and changing the amount of feedback based on the determined variation; and increasing or decreasing the quantization step size based on the measured differential amount of code and the changed amount of feedback. If there are a plurality of the predetermined conditions, a final variation for the amount of feedback may be determined by applying a specific operation to variations for the amount of feedback, which are determined for the individual conditions.
    Type: Application
    Filed: March 5, 2008
    Publication date: January 21, 2010
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Atsushi Shimizu, Ryuichi Tanida
  • Patent number: 7649940
    Abstract: The invention relates to an image coding apparatus which can improve the picture quality of an image. A quantization scale arithmetic operation section 43 calculates a coefficient of a quantization index based on a variance of values of a motion vector residual outputted from a motion vector residual variable buffer section 72 and an activity outputted from an activity buffer section 73. The quantization scale arithmetic operation section 43 calculates a quantization scale based on the coefficient of the quantization index calculated thereby and the quantization index outputted from the quantization index arithmetic operation section 42. The present invention can be applied to an image coding apparatus of the MPEG system.
    Type: Grant
    Filed: August 6, 2002
    Date of Patent: January 19, 2010
    Assignee: Sony Corporation
    Inventors: Hidehiko Morisada, Makoto Yamada
  • Patent number: 7620104
    Abstract: A digital video coding system is provided that is capable of reducing the load of a CPU (Central Processing Unit) that controls a video coding system for implementing a digital video data compression/decompression standard such as MPEG-1, 2, 4, H.261 or H.263. In a conventional video coding system, the circuit configuration and control method of a variable length encoder are becoming increasingly complex with the development of a video compression/decompression standard. In a conventional system structure, a complex control operation must be carried out, such that there is a problem in that the load of the CPU controlling the video coding system increases. Thus, the video coding technology is provided to reduce the load of the CPU necessary for controlling a VLC (Variable Length Coding) unit.
    Type: Grant
    Filed: January 12, 2005
    Date of Patent: November 17, 2009
    Assignee: C&S Technology Co., Ltd.
    Inventor: Hyun Il Byun
  • Patent number: 7606350
    Abstract: Improved DSL and/or other communication system services can be provided by motivating users, service providers and operators to implement and comply with one or more operational conditions, such as parameter value limits and/or ranges, that enhance operation of the communication system. Enhanced operation can include providing a reward such as an operational benefit to one or more users and/or mitigating problems experienced by other users in the communication system, which can be one or more communication lines. A DSL line implementing and complying with one or more operational conditions is provided with a reward (such as an operational benefit like a higher maximum data rate), which is otherwise withheld if the line fails to comply with the condition(s). Each operational condition may be set and monitored by a controller, such as a DSL optimizer that collects and analyzes operational data to determine compliance.
    Type: Grant
    Filed: May 5, 2005
    Date of Patent: October 20, 2009
    Assignee: Adaptive Spectrum and Signal Alignment, Inc.
    Inventors: John M. Cioffi, Wonjong Rhee
  • Publication number: 20090201987
    Abstract: The present application provides a method and apparatus for playing a mobile video program. The mobile video playing method and apparatus provided by the invention buffer the program content received in real time when there is a considerable movement state change. After the movement state becomes stable, playing will be resumed. While playing is resumed, the buffered contents can be firstly played (including the playing manners such as skipping, fast forward, etc), and then a program content received in real time will be played after all the buffered contents have been processed. According to the mobile video playing method provided by the invention, both the user's requirement for the continuity of a program content and the user's viewing effect will not be influenced by a fierce change of movement state of the mobile video apparatus.
    Type: Application
    Filed: May 15, 2007
    Publication date: August 13, 2009
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventor: Sheng Jin
  • Patent number: 7555041
    Abstract: Code quantity control based on a virtual buffer is executed by using information extracted from picture compressed information conforming to a predetermined system. Thus, a reference quantization scale can be held at a fixed value throughout a frame. As a result, it is possible to generate picture compressed information having a smaller code quantity.
    Type: Grant
    Filed: June 23, 2005
    Date of Patent: June 30, 2009
    Assignee: Sony Corporation
    Inventor: Kazushi Sato
  • Patent number: 7535959
    Abstract: A video encoder includes a programmable rate controller. In one embodiment, the programmable rate controller includes a variable bit rate controller, a constant bit rate controller, and an arbitration logic for selecting one of the two outputs. An embodiment of a variable bit rate controller tracks long-term changes to average bit rate. An embodiment of a constant bit rate controller classifies macroblock types, determines a statistical indicator of complexity for each macroblock type, and generates a target bit rate based on estimated complexity.
    Type: Grant
    Filed: October 16, 2003
    Date of Patent: May 19, 2009
    Assignee: NVIDIA Corporation
    Inventors: Michael L. Lightstone, Stefan Eckart
  • Patent number: 7492819
    Abstract: In order to enhance the picture quality of a detected area, the present invention provides a video coding apparatus. In the apparatus, a reliability indicative of the degree of coincidence of an area detected by an important area detecting section with a real important area is calculated, and a coding parameter calculating section calculates a coding parameter to be set to the detected area according to the reliability, thereby controlling the picture quality of the detected area. Consequently, a whole image has a coding bit amount which does not break the restrictions of a transmission bit rate, and a larger coding bit amount is assigned to the important area so that a picture quality thereof can be improved and a visibility can be enhanced. In addition, the picture quality is more enhanced if a probability that the detected area might be an important area is higher.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: February 17, 2009
    Assignee: Panasonic Corporation
    Inventors: Yoshimasa Honda, Tsutomu Uenoyama
  • Patent number: 7483479
    Abstract: An adaptive transversal filter having tap weights Wj which are products of corresponding tap coefficients Cj and tap gains Mj is provided. A filter control loop controls all of the tap coefficients Cj such that an error signal derived from the filter output is minimized. One or more tap control loops controls a tap gain Mk such that the corresponding tap coefficient Ck satisfies a predetermined control condition. For example, |Ck| can be maximized subject to a constraint |Ck|?Cmax, where Cmax is a predetermined maximum coefficient value. In this manner, the effect of quantization noise on the coefficients Cj can be reduced. Multiple tap control loops can be employed, one for each tap. Alternatively, a single tap control loop can be used to control multiple taps by time interleaving.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: January 27, 2009
    Assignee: KeyEye Communications
    Inventors: Mark Joseph Callicotte, Hiroshi Takatori
  • Patent number: 7460597
    Abstract: An encoding apparatus and method prevents image deterioration generated by repeatedly performing encoding and decoding by using a quantization matrix for quantization which is different from a quantization matrix for inverse quantization. In the encoding apparatus, a matrix selector selects a first quantization matrix in accordance with the complexity of an encoded picture pattern, and supplies a quantizer with information on the selected first quantization matrix. A matrix unit rewrites, by information on a second quantization matrix, the information described in an encoded stream output from a variable length code unit so that a quantization matrix to be used for inverse quantization is a second quantization matrix different from the first quantization matrix.
    Type: Grant
    Filed: March 10, 2005
    Date of Patent: December 2, 2008
    Assignee: Sony Corporation
    Inventor: Kanji Mihara
  • Patent number: 7453938
    Abstract: A rate control system is disclosed for video coding applications. The rate controller assigns a quantization parameter for video data in a picture in response to complexity indicators indicative of spatial complexity, motion complexity and/or bits per pel of the picture. A virtual buffer based quantizer parameter is proposed based on a virtual buffer fullness analysis and a target rate estimate, which is derived from the complexity indicators. A second quantizer parameter is proposed from a linear regression analysis of quantizer parameters used to code previously coded pictures of similar type (e.g., I pictures, P pictures or B pictures). A coding policy decision unit defines a final quantizer parameter from a comparison of the two proposed quantizer parameters.
    Type: Grant
    Filed: March 30, 2004
    Date of Patent: November 18, 2008
    Assignee: Apple Inc.
    Inventors: Barin Geoffry Haskell, Adriana Dumitras, James Normile, Hsi-Jung Wu, Xiaochun Nie, Atul Puri
  • Patent number: 7418007
    Abstract: A statistical multiplexer for coding and multiplexing multiple channels of digital television data, or multiple panels of HDTV digital television data. A bit rate need parameter is determined for each encoder in a stat mux group, and an encoding bit rate is allocated to each channel based on its need parameter. A transmission bit rate is allocated to each channel as a time-lagged version of its need parameter to minimize a rate mismatch between the output and the input of a decoder buffer. A packet processor checks for impending decoder buffer overflow or underflow events to set minimum and maximum limits on the transmission bit rate. Moreover, these limits are set based on whether a new transmission bit rate can be implemented before the decoding time stamp (DTS) of the current or next frame.
    Type: Grant
    Filed: September 20, 2000
    Date of Patent: August 26, 2008
    Assignee: General Instrument Corporation
    Inventors: Vincent Liu, Siu-Wai Wu, Michael Casteloes, Robert J. Stone, Rebecca Lam
  • Patent number: 7391809
    Abstract: A scalable video transcoder with limited drifting error is disclosed. The transcoder accumulates re-quantization errors of I-frames or P-frames. The accumulated errors are only selectively introduced into the transcoding loop in every block to compensate for transcoding errors. A threshold algorithm adaptively utilizes the accumulated errors at block level to control drifting error at an acceptable limited level. Transcoder complexity is scalable because a DCT transform may be removed from the transcoder loop when the accumulated errors are not used for compensation. The re-quantization process can be simply implemented by look-up table(s), which significantly reduces the complexity of the re-quantization process.
    Type: Grant
    Filed: December 30, 2003
    Date of Patent: June 24, 2008
    Assignee: Microsoft Corporation
    Inventors: Shipeng Li, Lujun Yuan, Qi Chen, Feng Wu
  • Patent number: 7372916
    Abstract: Digital signals are transmitted on a bus at given instants selectively in a non-encoded format and an encoded format. The decision whether to transmit the signals in non-encoded format or in encoded format is taken in part, based on a comparison of the signal to be transmitted on the bus for an instant of the aforesaid given instants with the signal transmitter on the bus for the preceding instant, so as to minimize switching activity on the bus.
    Type: Grant
    Filed: September 25, 2003
    Date of Patent: May 13, 2008
    Assignee: STMicroelectronics S.r.l
    Inventors: Francesco Pappalardo, Giuseppe Notarangelo
  • Patent number: 7340394
    Abstract: An audio encoder regulates quality and bitrate with a control strategy. The strategy includes several features. First, an encoder regulates quantization using quality, minimum bit count, and maximum bit count parameters. Second, an encoder regulates quantization using a noise measure that indicates reliability of a complexity measure. Third, an encoder normalizes a control parameter value according to block size for a variable-size block. Fourth, an encoder uses a bit-count control loop de-linked from a quality control loop. Fifth, an encoder addresses non-monotonicity of quality measurement as a function of quantization level when selecting a quantization level. Sixth, an encoder uses particular interpolation rules to find a quantization level in a quality or bit-count control loop. Seventh, an encoder filters a control parameter value to smooth quality. Eighth, an encoder corrects model bias by adjusting a control parameter value in view of current buffer fullness.
    Type: Grant
    Filed: October 26, 2005
    Date of Patent: March 4, 2008
    Assignee: Microsoft Corporation
    Inventors: Wei-Ge Chen, Naveen Thumpudi, Ming-Chieh Lee
  • Publication number: 20070297508
    Abstract: An image coding apparatus calculates an image change rate with respect to input image data, predicts an average activity appropriate for a coding target picture that is included in the input image data based on the image change rate, and normalizes an activity using the predicted value of the average activity. Based on the normalized activity, the image coding apparatus performs a quantization of the image data.
    Type: Application
    Filed: June 8, 2007
    Publication date: December 27, 2007
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Satoru Kobayashi
  • Patent number: 7302000
    Abstract: A method for two-pass video encoding using sliding windows. The method receives a video sequence (VS), selects a portion of frames in the VS from the beginning as an analysis window, encodes each frame in the analysis window to acquire multiple statistical features, such as a bitrate to each frame in the analysis window, the quantization scale or complexity of the frame, redistributes the bitrate to each frame in the analysis window according to the statistical features, encodes the frames in the analysis window occurring between the beginning and an out point according to the redistributed bitrates, and selects a portion of frames in the VS from the next frame of the out point as a new analysis window if the VS is not completely encoded.
    Type: Grant
    Filed: April 21, 2004
    Date of Patent: November 27, 2007
    Assignee: Ulead Systems, Inc.
    Inventor: Yi-Kai Chen
  • Patent number: 7295971
    Abstract: An audio encoder regulates quality and bitrate with a control strategy. The strategy includes several features. First, an encoder regulates quantization using quality, minimum bit count, and maximum bit count parameters. Second, an encoder regulates quantization using a noise measure that indicates reliability of a complexity measure. Third, an encoder normalizes a control parameter value according to block size for a variable-size block. Fourth, an encoder uses a bit-count control loop de-linked from a quality control loop. Fifth, an encoder addresses non-monotonicity of quality measurement as a function of quantization level when selecting a quantization level. Sixth, an encoder uses particular interpolation rules to find a quantization level in a quality or bit-count control loop. Seventh, an encoder filters a control parameter value to smooth quality. Eighth, an encoder corrects model bias by adjusting a control parameter value in view of current buffer fullness.
    Type: Grant
    Filed: November 14, 2006
    Date of Patent: November 13, 2007
    Assignee: Microsoft Corporation
    Inventors: Wei-Ge Chen, Naveen Thumpudi, Ming-Chieh Lee
  • Patent number: 7295609
    Abstract: An image information coding apparatus codes an input image signal in a manner optimized on the basis of the visual characteristics. In quantization, an input image signal is divided into blocks, an orthogonal transform is performed on a block-by-block basis, and resultant orthogonal transform coefficients are quantized. A quantizer includes a weighter for, in the quantization, performing weighting on each component of the orthogonal transform coefficients by means of an addition operation on a parameter specifying one of elements of a series of numbers arranged in accordance with a predetermined rule in correspondence with quantization step sizes.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: November 13, 2007
    Assignee: Sony Corporation
    Inventors: Kazushi Sato, Osamu Sunohara, Teruhiko Suzuki, Peter Kuhn, Yoichi Yagasaki, Kuniaki Takahashi
  • Patent number: 7280595
    Abstract: A motion-picture-experts group (MPEG) decoder performs AC prediction to decode first-column or first-row coefficients that are coded as differences from corresponding coefficients in a prior block or an above block. Rather than perform AC prediction between the variable-length decoder (VLD) and the inverse-quantizer (IQ), AC prediction is performed after the IQ. Post-IQ AC prediction allows the VLD and IQ to be constructed as a unified stage, improving decoding speed or efficiency as a single hardware stage can be used for the combined VLD/IQ. Rather than store prior-block quantized DCT coefficients, a coefficient store stores post-IQ DCT coefficients and quantization parameters. A Q-subtractor operates on the IQ output using the current quantization parameter, while another Q-subtractor operates on the stored coefficients and stored quantization parameter. The Q-subtractor subtracts a signed, odd-rounded quantization parameter from a coefficient.
    Type: Grant
    Filed: October 21, 2003
    Date of Patent: October 9, 2007
    Assignee: RedRock Semiconductor, Ltd.
    Inventor: Tao Lin
  • Patent number: 7277484
    Abstract: An image coding method and apparatus considering human visual characteristics are provided. The image coding method comprises (a) modeling image quality distribution of an input image in units of scenes such that the quality of an image input in units of scenes is gradually lowered from a region of interest to a background region, (b) determining a quantization parameter of each region constituting one scene according to the result of modeling of image quality distribution, (c) quantizing image data in accordance with the quantization parameter, and (d) coding entropy of the quantized image data.
    Type: Grant
    Filed: January 6, 2003
    Date of Patent: October 2, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Woo-shik Kim, Dae-sung Cho, Shi-hwa Lee, Sang-wook Kim
  • Patent number: 7269219
    Abstract: A quantizer and dequantizer for use in a video coding system that applies non linear, piece-wise linear scaling functions to video information signals based on a value of a variable quantization parameter. The quantizer and dequantizer apply different non linear, piece-wise linear scaling functions to a DC luminance signal, a DC chrominance signal and an AC chrominance signal. A code for reporting updates of the value of the quantization parameter is interpreted to require larger changes when the quantization parameter initially is large and smaller changes when the quantization parameter initially is small.
    Type: Grant
    Filed: September 18, 2003
    Date of Patent: September 11, 2007
    Assignee: AT&T Corp.
    Inventors: Barin Geoffry Haskell, Atul Puri, Robert Louis Schmidt
  • Patent number: 7266148
    Abstract: Disclosed is a video transcoding apparatus converting a specific bit rate of an MPEG (moving pictures experts group) bit stream into a different rate thereof for transportation. The present invention includes a video pre-processing unit having a predetermined matrix structure and down-sampling a macro block decoded by the video decoder by transforming the macro block into a corresponding picture structure to the compressed video bit stream, a transcoding parameter control unit detecting information about a picture from a previous bit stream variable-length-decoded by the video decoder and setting up an encoding mode for a transcoding in accordance with the detected information, etc. Therefore, the present invention does not need the motion estimation unit of encoder and reduce the complexity of the bit allocation unit. When changing HD-rated MPEG sequence over 10 Mbps into NTSC-rated MPEG sequence below 6 Mbps, the present invention reduces calculation time and complexity of hardware.
    Type: Grant
    Filed: January 3, 2002
    Date of Patent: September 4, 2007
    Assignee: LG Electronics Inc.
    Inventor: Eung Tae Kim
  • Patent number: 7263126
    Abstract: A system and method are provided for adaptive rate control in the transcoding of video streams. The method comprises: accepting frames of an input MPEG encoded video stream; decoding the video stream; determining video stream complexity; for each frame, calculating an output video stream quantization parameter (Qo) responsive to determined video stream complexity; and, encoding the output video stream into a protocol using Qo. Some aspects further comprise accepting a target bit rate ratio (r) for transcoding that is equal to the ratio of the target output video stream number of bits per frame (No), to the input video stream number of bits per frame (Ni). Then, Qo is also calculated in response to the value of r. More explicitly, Qo is calculated in response to a complexity ratio of: an accumulated complexity in the output video stream, to an accumulated complexity in the input video stream.
    Type: Grant
    Filed: September 15, 2003
    Date of Patent: August 28, 2007
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Jie Zhao, Shijun Sun
  • Patent number: 7263482
    Abstract: An audio encoder regulates quality and bitrate with a control strategy. The strategy includes several features. For example, an encoder selects a quantization level within a range of quantization levels, where the selecting accounts for non-monotonicity of quality measure as a function of quantization level within the range. The encoder then quantizes audio information by the quantization level. Or, an encoder determines first and second quality measures associated with a first and second quantization levels, respectively, then determines a third quantization level within a quantization level range based upon location of a target quality on a trajectory of quality measure as a function of quantization level. The first and second quantization levels define endpoints of the quantization level range, and the first and second quality measures define endpoints of the trajectory. The function relates logarithm of quality measure in proportion to inverse logarithm of quantization level.
    Type: Grant
    Filed: February 24, 2005
    Date of Patent: August 28, 2007
    Assignee: Microsoft Corporation
    Inventors: Wei-Ge Chen, Naveen Thumpudi, Ming-Chieh Lee
  • Patent number: 7260525
    Abstract: An audio encoder regulates quality and bitrate with a control strategy. The strategy includes several features. First, an encoder regulates quantization using quality, minimum bit count, and maximum bit count parameters. Second, an encoder regulates quantization using a noise measure that indicates reliability of a complexity measure. Third, an encoder normalizes a control parameter value according to block size for a variable-size block. Fourth, an encoder uses a bit-count control loop de-linked from a quality control loop. Fifth, an encoder addresses non-monotonicity of quality measurement as a function of quantization level when selecting a quantization level. Sixth, an encoder uses particular interpolation rules to find a quantization level in a quality or bit-count control loop. Seventh, an encoder filters a control parameter value to smooth quality. Eighth, an encoder corrects model bias by adjusting a control parameter value in view of current buffer fullness.
    Type: Grant
    Filed: February 24, 2005
    Date of Patent: August 21, 2007
    Assignee: Microsoft Corporation
    Inventors: Wei-Ge Chen, Ming-Chieh Lee, Naveen Thumpudi
  • Patent number: 7236521
    Abstract: A run-level domain transcoder receives a stream of compressed frames carried in a bit stream. The run-level domain transcoder decodes the bit stream into run-level pairs and selectively processes the compressed frames so as to, among other things, reduce the number of bits necessary to represent the compressed frames.
    Type: Grant
    Filed: March 26, 2003
    Date of Patent: June 26, 2007
    Assignee: Scientific-Atlanta, Inc.
    Inventor: Joel W. Schoenblum
  • Patent number: 7221706
    Abstract: The present invention is related to video encoding. In an embodiment, a bit budget is calculated for a first scene. In addition, bit budgets for corresponding frames, including at least a first frame, within the first scene are determined. Optionally, bit budgets corresponding to macroblocks within the first frame are also determined.
    Type: Grant
    Filed: October 4, 2004
    Date of Patent: May 22, 2007
    Assignee: Intervideo, Inc.
    Inventors: Lifeng Zhao, Ioannis Katsavounidis
  • Patent number: 7212571
    Abstract: A method for encoding video data to reduce blocking artifacts is provided. The method initiates with identifying a macro-block as being associated with a blocking artifact. For example the macro-block may be identified as a low activity macro-block or a high activity macro-block. Then, blocking artifacts introduced through a compression operation are mitigated by adjusting both a quantization parameter and an amount of bits generated from the quantization parameter. A video encoder and a system for processing image data associated with block based compression are provided.
    Type: Grant
    Filed: January 31, 2003
    Date of Patent: May 1, 2007
    Assignee: Seiko Epson Corporation
    Inventors: Vasudev Bhaskaran, Changick Kim
  • Patent number: RE40679
    Abstract: This invention employs a scheme to allow an input video signal to undergo encoding, e.g., predictive encoding, DCT processing, quantization at fixed quantization step size and variable length encoding to generate first encoded data to determine (calculate) allocated code quantity every frame or every GOP on the basis of data quantity every predetermined time, e.g., every frame or every GOP of the first encoded data and total quantity of usable data to encode the input video signal every predetermined time on the basis of the allocated code quantity to generate second encoded data. Thus, variable rate encoding such that encoding rate changes every predetermined time is realized. As a result, even if pictures (frames) of complicated are successive, there is no possibility that quantization step size is caused to be large with respect to these pictures as in the conventional apparatus. Thus, uniform high picture quality can be obtained through the entirety.
    Type: Grant
    Filed: December 29, 1999
    Date of Patent: March 24, 2009
    Assignee: Sony Corporation
    Inventor: Tsuyoshi Oda