Patent application number | Description | Published |
20100141489 | FAST PARSING OF VARIABLE-TO-FIXED-LENGTH CODES - Methods and systems for parsing and decoding compressed data are provided. Random segments of the compressed data may be decompressed and positioned appropriately in the corresponding uncompressed data set. The methods and systems utilize variable to fixed length (VF) coding techniques. For some applications, the VF coding techniques may be implemented within media encoders, decoders, or combined encoder-decoders (CODECs). | 06-10-2010 |
20100262427 | LOW COMPLEXITY SPECTRAL BAND REPLICATION (SBR) FILTERBANKS - A complex analysis filterbank is implemented by obtaining an input audio signal as a plurality of N time-domain input samples. Pair-wise additions and subtractions of the time-domain input samples is performed to obtain a first and second groups of intermediate samples, each group having N/2 intermediate samples. The signs of odd-indexed intermediate samples in the second group are then inverted. A first transform is applied to the first group of intermediate samples to obtain a first group of output coefficients in the frequency domain. A second transform is applied to the second group of intermediate samples to obtain an intermediate second group of output coefficients in the frequency domain. The order of coefficients in the intermediate second group of output coefficients is then reversed to obtain a second group of output coefficients. The first and second groups of output coefficients may be stored and/or transmitted as a frequency domain representation of the audio signal. | 10-14-2010 |
20100266008 | COMPUTING EVEN-SIZED DISCRETE COSINE TRANSFORMS - In general, techniques are described for computing even-sized discrete cosine transforms (DCTs). For example, a coding device may implement these techniques. The coding device includes a DCT-II unit that first determines whether a DCT-II to perform is a multiple of two, and in response to determining that the DCT-II to perform is a multiple of two, performs the DCT-II. To perform the DCT-II, the DCT-II unit computes a butterfly and reverses an order of a first sub-set of the outputs of the butterfly. The DCT-II unit then recursively subtracts the reverse-ordered first sub-set of the butterfly outputs. The DCT-II unit computes a sub-DCT-II for a second sub-set of the butterfly outputs and a sub-DCT-III for the recursively subtracted first set of butterfly outputs. The DCT-II unit reorders the outputs produced by the sub-DCT-II and sub-DCT-III to generate output values of the DCT-II. | 10-21-2010 |
20100309974 | 4X4 TRANSFORM FOR MEDIA CODING - In general, techniques are described that provide for 4×4 transforms for media coding. A number of different 4×4 transforms are described that adhere to these techniques. As one example, an apparatus includes a 4×4 discrete cosine transform (DCT) hardware unit. The DCT hardware unit implements an orthogonal 4×4 DCT having an odd portion that applies first and second internal factors (C, S) that are related to a scaled factor (ξ) such that the scaled factor equals a square root of a sum of a square of the first internal factor (C) plus a square of the second internal factor (S). The 4×4 DCT hardware unit applies the 4×4 DCT implementation to media data to transform the media data from a spatial domain to a frequency domain. As another example, an apparatus implements a non-orthogonal 4×4 DCT to improve coding gain. | 12-09-2010 |
20100312811 | 4X4 TRANSFORM FOR MEDIA CODING - In general, techniques are described that provide for 4×4 transforms for media coding. A number of different 4×4 transforms are described that adhere to these techniques. As one example, an apparatus includes a 4×4 discrete cosine transform (DCT) hardware unit. The DCT hardware unit implements an orthogonal 4×4 DCT having an odd portion that applies first and second internal factors (C, S) that are related to a scaled factor (ξ) such that the scaled factor equals a square root of a sum of a square of the first internal factor (C) plus a square of the second internal factor (S). The 4×4 DCT hardware unit applies the 4×4 DCT implementation to media data to transform the media data from a spatial domain to a frequency domain. As another example, an apparatus implements a non-orthogonal 4×4 DCT to improve coding gain. | 12-09-2010 |
20100329329 | 8-POINT TRANSFORM FOR MEDIA DATA CODING - In general, techniques are described for implementing an 8-point inverse discrete cosine transform (IDCT). An apparatus comprising an 8-point inverse discrete cosine transform (IDCT) hardware unit may implement these techniques to transform media data from a frequency domain to a spatial domain. The 8-point IDCT hardware unit includes an even portion comprising factors A, B that are related to a first scaled factor (μ) in accordance with a first relationship. The 8-point IDCT hardware unit also includes an odd portion comprising third, fourth, fifth and sixth internal factors (G, D, E, Z) that are related to a second scaled factor (η) in accordance with a second relationship. The first relationship relates the first scaled factor to the first and second internal factors. The second relationship relates the second scaled factor to the third, fourth, fifth and sixth internal factors. | 12-30-2010 |
20110075724 | ENCODING PARAMETERS WITH UNIT SUM - In general, techniques are described for encoding parameters with unit sum. In one example, an apparatus comprising a control unit implements these parameter encoding techniques. The control unit determines parameters that sum to a constant or unit sum. The control unit includes a parameter coding unit that segments a space that contains the plurality of parameters into a set of portions. The parameter coding unit assigns a different one of a plurality of codewords to each of the portions, selects one of the set of portions that contains a point defined by the plurality of parameters, and codes the plurality of parameters using one of the plurality of codewords assigned to the selected one of the plurality of portions. Rather than code only a subset of these parameters, the parameter coding unit codes all of the parameters with the result of potentially reducing quantization error. | 03-31-2011 |
20110150078 | 8-POINT TRANSFORM FOR MEDIA DATA CODING - In general, techniques are described for implementing an 8-point discrete cosine transform (DCT). An apparatus comprising an 8-point discrete cosine transform (DCT) hardware unit may implement these techniques to transform media data from a spatial domain to a frequency domain. The 8-point DCT hardware unit includes an even portion comprising factors A, B that are related to a first scaled factor (μ) in accordance with a first relationship. The 8-point DCT hardware unit also includes an odd portion comprising third, fourth, fifth and sixth internal factors (G, D, E, Z) that are related to a second scaled factor (η) in accordance with a second relationship. The first relationship relates the first scaled factor to the first and second internal factors. The second relationship relates the second scaled factor to the third internal factor and a fourth internal factor, as well as, the fifth internal factor and a sixth internal factor. | 06-23-2011 |
20110150079 | 16-POINT TRANSFORM FOR MEDIA DATA CODING - In general, techniques are described for implementing a 16-point discrete cosine transform (DCT) that is capable of applying multiple IDCT of different sizes. For example, an apparatus comprising a 16-point discrete cosine transform of type II (DCT-II) unit may implement the techniques of this disclosure. The 16-point DCT-II unit performs these DCTs-II of different sizes to transform data from a spatial to a frequency domain. The 16-point DCT-II unit includes an 8-point DCT-II unit that performs one of the DCTs-II of size 8 and a first 4-point DCT-II unit that performs one of the DCTs-II of size 4. The 8-point DCT-II unit includes the first 4-point DCT-II unit. The 16-point DCT-II unit also comprises an 8-point DCT-IV unit that includes a second 4-point DCT-II unit and a third 4-point DCT-II unit. Each of the second and third 4-point DCT-II units performs one of the DCTs-II of size 4. | 06-23-2011 |
20110153699 | 16-POINT TRANSFORM FOR MEDIA DATA CODING - In general, techniques are described for implementing a 16-point inverse discrete cosine transform (IDCT) that is capable of applying multiple IDCTs of different sizes. For example, an apparatus comprising a 16-point inverse discrete cosine transform of type II (IDCT-II) unit may implement the techniques of this disclosure. The 16-point IDCT-II unit performs these IDCTs-II of different sizes to transform data from a spatial to a frequency domain. The 16-point IDCT-II unit includes an 8-point IDCT-II unit that performs one of the IDCTs-II of size 8 and a first 4-point IDCT-II unit that performs one of the IDCTs-II of size 4. The 8-point IDCT-II unit includes the first 4-point DCT-II unit. The 16-point IDCT-II unit also comprises an inverse 8-point DCT-IV unit that includes a second 4-point IDCT-II unit and a third 4-point IDCT-II unit. Each of the second and third 4-point IDCT-II units performs one of the IDCTs-II of size 4. | 06-23-2011 |
20110222774 | IMAGE FEATURE DETECTION BASED ON APPLICATION OF MULTIPLE FEATURE DETECTORS - In a particular embodiment, a method includes applying a first feature detector to a portion of an image to detect a first set of features. The first set of features is used to locate a region of interest, and a boundary corresponding to the region of interest is determined. The method also includes displaying the boundary at a display. In response to receiving user input to accept the displayed boundary, a second feature detector is applied to an area of the image encapsulated by the boundary. | 09-15-2011 |
20110255781 | EFFICIENT DESCRIPTOR EXTRACTION OVER MULTIPLE LEVELS OF AN IMAGE SCALE SPACE - A local feature descriptor for a point in an image is generated over multiple levels of an image scale space. The image is gradually smoothened to obtain a plurality of scale spaces. A point may be identified as the point of interest within a first scale space from the plurality of scale spaces. A plurality of image derivatives is obtained for each of the plurality of scale spaces. A plurality of orientation maps is obtained (from the plurality of image derivatives) for each scale space in the plurality of scale spaces. Each of the plurality of orientation maps is then smoothened (e.g., convolved) to obtain a corresponding plurality of smoothed orientation maps. Therefore, a local feature descriptor for the point may be generated by sparsely sampling a plurality of smoothed orientation maps corresponding to two or more scale spaces from the plurality of scale spaces. | 10-20-2011 |
20120014455 | Variable Localized Bit-Depth Increase for Fixed-Point Transforms in Video Coding - This disclosure describes techniques for mitigating rounding errors in a fixed-point transform associated with video coding by applying a variable localized bit-depth increase at the transform. More specifically, the techniques include selecting a constant value based on a size of a fixed-point transform in a video coding device and applying a variable localized bit-depth increase at the transform with a value equal to the constant value. Applying the variable localized bit-depth increase includes left-shifting a transform input signal by a number of bits equal to the constant value before the fixed-point transform, and right-shifting a transform output signal by a number of bits equal to the constant value after the fixed-point transform. The constant value is selected from a plurality of constant values stored on the video coding device. Each of the constant values is pre-calculated for one of a plurality of different transform sizes supported by the video coding. | 01-19-2012 |
20120027077 | CODING BLOCKS OF DATA USING A GENERALIZED FORM OF GOLOMB CODES - In general, techniques are described for coding blocks of data using a generalized form of Golomb codes. In one example, a device may implement these techniques for encoding data that includes samples, each of which includes a set of values. The device includes a lossless coding unit. This lossless coding unit comprises a sample summation unit that computes a sum of the values of a first one of the samples and a counting unit that determines a sample index. The lossless coding unit further includes a variable length coding unit that codes the computed sum using a variable-length code to generate a coded sum and a uniform coding unit that codes the determined sample index using a uniform code to generate a coded sample index. The lossless coding unit also includes a format unit that combines the coded sum and the coded sample index to form a bitstream. | 02-02-2012 |
20120027290 | OBJECT RECOGNITION USING INCREMENTAL FEATURE EXTRACTION - In one example, an apparatus includes a processor configured to extract a first set of one or more keypoints from a first set of blurred images of a first octave of a received image, calculate a first set of one or more descriptors for the first set of keypoints, receive a confidence value for a result produced by querying a feature descriptor database with the first set of descriptors, wherein the result comprises information describing an identity of an object in the received image, and extract a second set of one or more keypoints from a second set of blurred images of a second octave of the received image when the confidence value does not exceed a confidence threshold. In this manner, the processor may perform incremental feature descriptor extraction, which may improve computational efficiency of object recognition in digital images. | 02-02-2012 |
20120039384 | CODING BLOCKS OF DATA USING ONE-TO-ONE CODES - In general, techniques are described for coding data defining a sequence using one-to-one codes. An apparatus comprising a processing unit and a storage unit may implement the techniques. The processing unit decodes the index using a combinatorial enumeration process to generate a sequence. The index identifies the sequence in an array of all possible sequences ordered according to probabilities of the possible sequences assuming the possible sequences are produced by a memoryless source. The combinatorial enumeration process reorders sequences from the memoryless source according to the corresponding probabilities. The storage unit stores the sequence. | 02-16-2012 |
20120109993 | Performing Visual Search in a Network - In general, techniques are described for performing a visual search in a network. A client device comprising an interface, a feature extraction unit and a feature compression unit may implement various aspects of the techniques. The feature extraction unit extracts feature descriptors from an image. The feature compression unit quantizes the image feature descriptors at a first quantization level. The interface that transmits the first query data to the visual search device via the network. The feature compression unit determines second query data that augments the first query data such that when the first query data is updated with the second query data the updated first query data is representative of the image feature descriptors quantized at a second quantization level. The interface transmits the second query data to the visual search device via the network to successively refine the first query data. | 05-03-2012 |
20120110025 | CODING ORDER-INDEPENDENT COLLECTIONS OF WORDS - In general, techniques are described for order-independent coding of a collection of words. An apparatus comprising a compression unit and an interface may implement the techniques. The compression unit constructs a digital search tree to store two or more words. A prefix of each of the words identifies a path from a root node to the node storing the corresponding word. A suffix of each of the words is stored in the node identified by the corresponding prefix. The compression unit traverses the digital search tree data structure, retrieving each of the suffixes in accordance with a defined order and encodes the suffixes. The compression unit encodes the digital search tree data structure in a manner that encodes an arrangement but not the placement of the nodes. The interface transmits the encoded digital search structure and the encoded suffixes in the defined order. | 05-03-2012 |
20120133537 | PERFORMING ENHANCED SIGMA-DELTA MODULATION - In general, techniques are described for performing enhanced sigma-delta modulation. For example, an apparatus comprising a predictive filter unit, an amplifier, an oversampling unit and a sigma-delta modulation unit may implement the techniques. The predictive filter unit performs predictive filtering on an input signal to generate a filtered signal and computes an estimate of a predictive gain as a function of an energy of the input signal and an energy of the filtered signal. The amplifier receives the filtered signal and amplifies the filtered signal based on the predictive gain to generate an amplified signal. The oversampling unit receives the amplifies signal and performs oversampling in accordance with an oversampling rate to generate an oversampled signal. The sigma-delta modulation unit receives the oversampled signal and performs sigma-delta modulation to generate a modulated signal. | 05-31-2012 |
20120177108 | 32-POINT TRANSFORM FOR MEDIA DATA CODING - In general, techniques are described for implementing a 32-point discrete cosine transform (DCT) that is capable of applying multiple DCTs of different sizes. For example, an apparatus comprising a 32-point discrete cosine transform of type II (DCT-II) unit may implement the techniques of this disclosure. The 32-point DCT-II unit performs these DCTs-II of different sizes to transform data from a spatial to a frequency domain. The 32-point DCT-II unit includes an 16-point DCT-II unit that performs one of the DCTs-II of size 16 and at least one 8-point DCT-II unit that performs one of the DCTs-II of size 8. The 16-point DCT-II unit includes another 8-point DCT-II unit. The 16-point DCT-II unit also comprises at least one 4-point DCTs-II unit. Two or more of these DCTs-II units may concurrently perform DCTs-II of different sizes to various portions of the content data. | 07-12-2012 |
20120263388 | ROBUST FEATURE MATCHING FOR VISUAL SEARCH - Techniques are disclosed for performing robust feature matching for visual search. An apparatus comprising an interface and a feature matching unit may implement these techniques. The interface receives a query feature descriptor. The feature matching unit then computes a distance between a query feature descriptor and reference feature descriptors and determines a first group of the computed distances and a second group of the computed distances in accordance with a clustering algorithm, where this second group of computed distances comprises two or more of the computed distances. The feature matching unit then determines whether the query feature descriptor matches one of the reference feature descriptors associated with a smallest one of the computed distances based on the determined first group and second group of the computed distances. | 10-18-2012 |
20120330967 | Descriptor storage and searches of k-dimensional trees - Various arrangements for using a k-dimensional tree for a search are presented. A plurality of descriptors may be stored. Each of the plurality of descriptors stored is linked with a first number of stored dimensions. The search may be performed using the k-dimensional tree for one or more query descriptors that at least approximately match one or more of the plurality of descriptors linked with the first number of stored dimensions. The k-dimensional tree may be built using the plurality of descriptors wherein each of the plurality of descriptors is linked with a second number of dimensions when the k-dimensional tree is built. The second number of dimensions may be a greater number of dimensions than the first number of stored dimensions. | 12-27-2012 |
20130046793 | FAST MATCHING OF IMAGE FEATURES USING MULTI-DIMENSIONAL TREE DATA STRUCTURES - A method for generating a descriptor tree data structure is provided. A plurality of descriptors are obtained for one or more images, each descriptor defined within a multi-dimensional descriptor space. The plurality of descriptors are partitioned into nodes of a tree data structure, where the number of nodes in such partitioning is a function of the number of descriptors in the plurality of descriptors. The nodes having more than two descriptors may be sub-partitioned into sub-nodes of the tree data structure until two or fewer descriptors remain per sub-node, where such sub-partitioning is a function of the number of descriptors remaining in each such node and/or a dimensionality of such descriptors. | 02-21-2013 |