Showing papers on "Encoding (memory) published in 1997"

What memory is for.

Abstract: Let's start from scratch in thinking about what memory is for, and consequently, how it works. Suppose that memory and conceptualization work in the service of perception and action. In this case, conceptualization is the encoding of patterns of possible physical interaction with a three-dimensional world. These patterns are constrained by the structure of the environment, the structure of our bodies, and memory. Thus, how we perceive and conceive of the environment is determined by the types of bodies we have. Such a memory would not have associations. Instead, how concepts become related (and what it means to be related) is determined by how separate patterns of actions can be combined given the constraints of our bodies. I call this combination "mesh." To avoid hallucination, conceptualization would normally be driven by the environment, and patterns of action from memory would play a supporting, but automatic, role. A significant human skill is learning to suppress the overriding contribution of the environment to conceptualization, thereby allowing memory to guide conceptualization. The effort used in suppressing input from the environment pays off by allowing prediction, recollective memory, and language comprehension. I review theoretical work in cognitive science and empirical work in memory and language comprehension that suggest that it may be possible to investigate connections between topics as disparate as infantile amnesia and mental-model theory.

Separate Neural Bases of Two Fundamental Memory Processes in the Human Medial Temporal Lobe

Abstract: The participation of medial temporal-lobe structures in memory performance was examined by functional magnetic resonance imaging of local blood oxygenation level–dependent signals. Signals were measured during encoding into memory complex scenes or line drawings and during retrieval from memory of previously studied line drawings or words. Encoding tasks yielded increased signals for unfamiliar information in a posterior medial-temporal region that were focused in the parahippocampal cortex. Retrieval tasks yielded increased signals for successfully remembered information in an anterior medial-temporal region that were focused in the subiculum. These results indicate that separate components of the human medial temporal-lobe memory system are active during distinct memory processes.

Memory for items and memory for relations in the procedural/declarative memory framework.

Abstract: A major area of research in memory and amnesia concerns the item specificity of implicit memory. In this paper we address several issues about the nature of implicit memory phenomena and about what constitutes an "item", using the procedural/declarative memory theory to guide us. We consider the nature of memory for items and of memory for relations among items, within the context of the procedural/declarative framework, providing us with the foundation necessary to analyse the basis for item-specific implicit memory phenomena. We review recent work from our laboratories demonstrating the fundamentally relational and flexible nature of declarative memory representation, in both humans and animals, and the essential role of the hippocampal system in relational memory processing. We show, further, that the memory representations supporting implicit memory phenomena are inflexible and nonrelational, and are tied to specific processing modules. Finally, we introduce empirical approaches that blur the distinction between skill learning and repetition priming, and show computational modelling results that demonstrate how these two implicit memory phenomena can be mediated by a single incremental learning mechanism, in accord with the claims of the procedural-declarative theory. Taken together, these various analyses of memory for items and memory for relations help to illuminate the nature of the functional deficit in amnesia and the memory systems of the brain.

Memory Development Between Two and Twenty

Abstract: Contents: Preface to the First Edition Preface to the Second Edition Memory Development Since We Wrote Last Time: Much Ado About Children's Autobiographical Memories A Brief History of Memory Development Research Basic Memory Capacities and Mechanisms The Knowledge Base Development of Encoding and Retrieval Strategies Metamemory Good Information Processing: A General Model, A Specific Example, and Comments on How to Do Research on the Development of Information-Processing Proficiency Is Good Strategy Use Possible? Conclusions

Asymptotic zero-transition activity encoding for address busses in low-power microprocessor-based systems

Abstract: In microprocessor-based systems, large power savings can be achieved through reduction of the transition activity of the on- and off-chip buses. This is because the total capacitance being switched when a voltage change occurs on a bus line is usually sensibly larger than the capacitive load that must be charged/discharged when internal nodes toggle. In this paper, we propose an encoding scheme which is suitable for reducing the switching activity on the lines of an address bus. The technique relies on the observation that, in a remarkable number of cases, patterns traveling onto address buses are consecutive. Under this condition it may therefore be possible, for the devices located at the receiving end of the bus, to automatically calculate the address to be received at the next clock cycle; consequently, the transmission of the new pattern can be avoided, resulting in an overall switching activity decrease. We present analytical and experimental analyses showing the improved performance of our encoding scheme when compared to both binary and Gray addressing schemes, the latter being widely accepted as the most efficient method for address bus encoding. We also propose power and timing efficient implementations of the encoding and the decoding logic, and we discuss the applicability of the technique to real microprocessor-based designs.

Aging and Prospective Memory: The Influence of Increased Task Demands at Encoding and Retrieval

Abstract: A feature of prospective memory tasks is that they tend to be embedded into other background activities. Two experiments examined how the demands of these background activities affect age differences in prospective memory. The first experiment showed that increasing the demands of the background activities (by adding a digit-monitoring task) significantly reduced prospective memory performance. Planned comparisons revealed that age differences in prospective memory were reliable only in the more demanding background condition. The second experiment revealed significant prospective memory declines when the demands were selectively increased at encoding for both younger and older adults. When the demands were selectively increased at retrieval, older adults were particularly affected. The authors propose a model that relies on both automatic retrieval processes and working memory resources to explain prospective memory remembering.

Brain regions supporting intentional and incidental memory: A PET study

Abstract: Regional brain activity associated with intentional and incidental memory retrieval was studied with PET. Previously studied and new words were presented in either an intentional or an incidental memory task. Type of task was crossed with an encoding manipulation ('deep' vs 'shallow') which varied the probability that studied items would be remembered. In both tasks, deeply encoded items were associated with greater activation in the left hippocampus than were items that had received shallow encoding, suggesting that the involvement of the hippocampus in memory retrieval is independent of whether remembering is intentional or incidental. Right prefrontal and bilateral parietal cortex were more activated during the international task than during the incidental task, irrespective of encoding condition. Thus, these regions play a more extensive role in memory retrieval when remembering is intentional.

Encrypted optical memory using double-random phase encoding.

Abstract: We describe an encrypted optical memory that uses double-random phase encoding at the input plane and the Fourier plane. This technique allows the images to be stored as independent white complex stationary processes. Experimental results and computer simulations are presented.

Dual encoding/compression method and system for picture quality/data density enhancement

Abstract: A digital compression apparatus and method uses a first compression encoding step associated with a first encode circuit to produce a first statistical data set from a first compression encoding of an initial digital video bit stream representing a group of pictures (GOP). The initial bit stream of the GOP is also stored in a first memory, while the first compression encoding is performed. Concurrently with, or following the first compression of the GOP data by the first encoder, a companion processor uses the first statistical data set and optional additional information to compute a set of filter and encoder control settings. The initial digital video bit stream of the GOP data previously stored in the first memory is retrieved from the memory after the first encoding step and is input as a time delayed version of the initial digital video bit stream through a set of filters and subsequently through a second compression encode circuit to produce a second compressed video bit stream of the GOP data. The filters are configured to provide dynamically variable filter characteristics that are responsive to the filter control settings from the companion processor. The filter characteristics can be changed optionally by the companion processor on a block, frame or GOP basis. The second encode circuit also has encoder characteristics responsive to the encoder control settings. The filter and encoder control settings selected by the companion enable the second encoder to provide enhanced compression encoding performance second compression encoding of the GOP data video bit stream relative to the compression of the first encode circuit. In particular, the second compressed bit stream may have improved performance in either or both bit rate and total bits relative to the compression of the first encode circuit.

System-level power optimization of special purpose applications: the beach solution

Abstract: This paper describes a new approach to low-power bus encoding, called "The Beach Solution", which is thought for power optimization of digital systems containing an embedded processor or a microcontroller executing a special-purpose software routine. The main difference between the proposed method and existing bus encoding techniques is that it is strongly application-dependent, in the sense that it is Based on the analysis of the execution stream of a given program. This allows an accurate computation of the correlations that may exist between blocks of bits in consecutive patterns, and that can be successfully exploited to determine an encoding which minimizes the bus transition activity. Experimental results, obtained on a set of special-purpose applications, are very promising; reductions of the bus activity up to 64.8% (41.9% on average) have been achieved over the original address streams.

Method and apparatus for supporting compressed video with explicit rate congestion control

Abstract: A method and system provide for adaptive coding for transporting of compressed video data. The method and system include techniques for predicting the rate which an encoder needs to be able to supply video to a network. The method and system also include the network receiving the demand rate and calculating an allocation rate which is ultimately fed back to the video source setting an explicit rate for the transporting of compressed video. Furthermore, it includes the adaptation of the encoding rate at the video source in accordance with the explicit rate allocated by the network in response to the demand.

Signal encoding method

Abstract: A signal encoding method for real-time encoding an acoustic signal using a small hardware. The spectral signal components of an input signal are split into encoding units as the units for encoding. At step ST102, an estimated value of the required number of bits is computed from one encoding unit to another. The total number of bits required in encoding the spectral signal components of the input signal is adjusted in steps ST103 and in the following steps based on the estimated value of the number of bits computed from one encoding unit to another.

Image decoder, image encoder, image communication system, and encoded bit stream converter

Abstract: An image decoder which can decode an encoded bit stream which is encoded by a different encoding system has an encoding system judging unit which judges the encoding system of the encoded bit stream in accordance with multiplexed encoding system identification information, a setting means which sets the header information of a 2nd encoding system in accordance with the header information of a 1st encoding system and a decoding means which decodes the encoded image data of the 1st encoding system in accordance with the header information of the set 2nd encoding system.

Gps receiver with efficient signal acquisition

Abstract: A direct sequence spread spectrum receiver samples an incoming signal and translates the signal to an IF signal. The IF signal is sampled ans stored in memory (192, 194). In one embodiment, the memory consists of two memory banks which alternately receive sample segments. During a write period to one of the memory banks, the other memory bank supplies its output to a processor (70). This continues in a ping-pong manner. In another embodiment, a single memory bank is filled and read as necessary, the receiver ignoring incoming signal until the processor has completed processing the sample available at the output of the memory. Such a receiver is useful in global positioning satellite (GPS) signal processing where the incoming signal contains several satellite transmissions encoded with CDMA encoding.

Data transaction typing for improved caching and prefetching characteristics

Abstract: A microprocessor assigns a data transaction type to each instruction. The data transaction type is based upon the encoding of the instruction, and indicates an access mode for memory operations corresponding to the instruction. The access mode may, for example, specify caching and prefetching characteristics for the memory operation. The access mode for each data transaction type is selected to enhance the speed of access by the microprocessor to the data, or to enhance the overall cache and prefetching efficiency of the microprocessor by inhibiting caching and/or prefetching for those memory operations. Instead of relying on data memory access patterns and overall program behavior to determine caching and prefetching operations, these operations are determined on an instruction-by-instruction basis. Additionally, the data transaction types assigned to different instruction encodings may be revealed to program developers. Program developers may use the instruction encodings (and instruction encodings which are assigned to a nil data transaction type causing a default access mode) to optimize use of processor resources during program execution.

Adaptive real-time encoding of video sequence employing image statistics

Abstract: Method, system and computer program product are provided for adaptively encoding in hardware, software or a combination thereof a sequence of video frames in real-time. A first encoding subsystem is employed to analyze the sequence of video frames to derive information on at least one characteristic thereof, such as motion statistics, non-motion statistics, scene change statistics, or scene fade statistics. The gathered information may comprise either an intraframe characteristic or an interframe characteristic. A second encoding subsystem, coupled to the first encoding subsystem, encodes the sequence of video frames employing at least one controllable parameter. The second encoding subsystem dynamically adapts intraframe or interframe encoding of the sequence of video frames by adjusting the at least one controllable parameter used in the encoding process in response to the derived information from the first encoding subsystem.

Context Memory and the Selection of Frequency Estimation Strategies

Abstract: When people estimate event frequency, they sometimes retrieve and count event instances. This study demonstrates a direct relation between the use of these enumeration-based strategies and the contents of memory. In 3 experiments, participants studied target-context word pairs, estimated presentation frequency for target words, and recalled context words. Study time, target-context relatedness, and study-phase instructions were manipulated, producing large differences in memory for context words. When context memory was best, estimation time increased sharply with presentation frequency, and the steepness of this estimation time-presentation frequency function decreased with context memory. These results indicate that enumeration was common only when context memory was good, that encoding factors determine how frequency is represented, and that the contents of memory restrict strategy selection.

Memory for to-be-performed tasks versus memory for performed tasks

Abstract: Memory for subject-performed tasks—that is, for simple actions such as lifting a pen, which subjects perform overtly—is better than memory for verbal tasks—that is, when subjects only listen to the action phrases. Here I investigated whether this effect depends on actual performance or whether it also shows up when there is only an intention to perform the task. Koriat, Ben-Zur, and Nussbaum (1990) found that the intention to perform items at test enhanced free recall more than did verbal tasks. Brooks and Gardiner (1994), however, were not able to replicate this finding. In four experiments, I attempted to reconcile this discrepancy by comparing subject-performed tasks, to-beperformed tasks, and verbal tasks under different conditions. The outcome depended on whether a within-subjects design or a between-subjects design was used. In the between-subjects design, memory for subject-performed tasks was better than memory for to-be-performed tasks, and both of these led to better recall performance than did verbal tasks. In a within-subjects design, in contrast, memory for to-be-performed tasks was no different from memory for verbal tasks. These results were independent of whether the test mode was congruent or incongruent. Thus, the discrepant findings of Koriat et al. and of Brooks and Gardiner seem to be due to the design used, pointing to encoding processes as the critical variable. The present results are interpreted to show that actual performance of actions at study provides more information than does only the intention to perform actions at test.

Device and method for decoding HDTV video

Abstract: HDTV video decoder circuit is disclosed, which has an 1/4 size frame memory for a progressive scanned or interlace scanned video and yet can conduct IDCT and motion compensation to fit to the reduced frame memory size, which, in comparison to a conventional MPEG-2 video decoder which uses a 4×4 IDCT that requires 1/4 frame memory in encoding an interlace scanned image into frame picture only to lose field information of the image resulting in a significant damage to the picture quality, facilitates to maintain the field information as it was resulting in an improvement in the picture quality.

Neuroanatomical correlates of implicit and explicit memory for structurally possible and impossible visual objects.

Abstract: Implicit memory refers to nonconscious retrieval of past experience demonstrated by facilitation in test performance on tasks that do not require intentional recollection of previous experiences. Explicit memory, in contrast, refers to the conscious retrieval of prior information, as demonstrated during standard recall and recognition tasks. In this experiment, positron emission tomographic (PET) measurements of regional cerebral blood flow (CBF), a marker of local neuronal activity, were used to identify and contrast brain regions that participate in the perception, implicit memory, and explicit memory for structurally possible and impossible visual objects. Ten CBF images were acquired in 16 normal women as they made possible/impossible and old/new recognition decisions about previously studied (old) and nonstudied (new) structurally possible and impossible objects. As reported previously, object decisions for familiar possible objects were associated with increased CBF in the vicinity of the left inferior temporal and fusiform gyri and recognition memory for familiar possible objects was associated with increased CBF in the vicinity of the right hippocampus. In this report, we provide more extensive analyses of the roles of the inferior temporal cortex, the hippocampus, the parahippocampus, and the pulvinar in encoding and retrieval operations. Additionally, patterns of CBF increases and decreases provide information regarding the neural structures involved in implicit and explicit memory.

Method and arrangement for encoding a video signal

Abstract: A video signal encoding method and arrangement are disclosed. The video encoder, for example, an MPEG encoder (2), produces a motion-compensated prediction image (PRED). Prior to encoding, said motion-compensated prediction image is combined (1) with the input image which effectively causes both the noise in the input image and quantization noise to be reduced. The amount of noise reduction is preferably controlled (15) in response to the same parameter (MAD) as is used by the motion estimator (29) to search for the most resembling pixel block in the prediction memory (28).

Method for encoding video signal using statistical information

Abstract: A picture encoding method employed in a system for encoding video signals of a motion picture for storage on a picture recording medium or in a system employed for transmitting video signals of a moving picture over a transmission channel. The encoding method includes a first step of generating the information on picture characteristics at least including the luminance information of the input video signals in terms of a pre-set time interval as a unit, a second step of calculating the information on the amount of generated bits of the information on picture characteristics in terms of a pre-set time interval as a unit, a third step of determining an encoding bit rate, based upon the information on picture characteristics, the information on the amount of the generated bits and the information on the total amount of data usable during transmission of encoded data, in terms of the pre-set time interval as a unit, and a fourth step of encoding the input video signals in accordance with the encoding bit rate in terms of the pre-set time as a unit for generating the encoded data.

Encoding, repetition, and the mirror effect in recognition memory: Symmetry in motion

Abstract: Attention/likelihood theory has been used to explain the mirror effect in recognition memory. The theory also predicts that any manipulation that affects the recognition of old items will also affect recognition of the new items—more specifically, that all the underlying distributions will move and that they will move symmetrically on the decision axis. In five experiments, we tested this prediction. The first two experiments used encoding tasks during study to change recognition performance for high- and low-frequency words. The results show symmetrical dispersion of the underlying distributions. The final three experiments used repetition to increase recognition performance. Repetition produced a symmetrical pattern of movement that was different from that produced by encoding task. This pattern is, however, also covered by attention/likelihood theory. A further extension of the theory was used to predict response times.

Image encoding method, image encoder, and recording medium recorded with image encoding program

Abstract: PROBLEM TO BE SOLVED: To improve encoding efficiency of mode information and to reduce code amount of an entire one frame in an encoding and decoding device which encodes data by dividing it into data about encoding mode information of a block and a pixel value in the block. SOLUTION: A mode information encoding means 2 creates a code word about mode information by estimating encoding object block mode information from mode information of ambient blocks that are already encoded and using a code word table in accordance with the hitting ratio of estimation, and a block data encoding means 3 encodes pixel data in a block by an encoding method according to mode information of the block and creates an encoding signal of a digital image. This accomplishes the improvement of encoding efficiency of the mode information. COPYRIGHT: (C)1998,JPO

Apparatus and method for encoding data

Abstract: A method of encoding data, involves the steps of comparing an input image from a video camera (2) with an image being built up, and stored in store (8). The images are processed by an analyser (10) in accordance with a plurality of different algorithms stored in a store (16) to produce a plurality of different data packets each representative of a partial change which can be effected to the image to be built up to bring it closer to the input image. The analyser (10) compares the effects of the different data packets if implemented on the data image to the built up and provides each one with a score in accordance with a predetermined criteria. A comparator (20) selects the packet with the best score under the predetermined criteria and uses it to alter the image in the store (8) accordingly. The cycle is repeated to cause the image to be built up, to progressively converge on the input image.

Method for controlling storage device, storage device and production of storage device

Abstract: PROBLEM TO BE SOLVED: To provide an inexpensive and highly reliable storage device using semiconductor memories as storage media. SOLUTION: A semiconductor storage device to be the storage device is constituted of loading a block control part 220, plural rearrangable memory blocks 200 each of which consists of plural semiconductor memory elements 210 and stand-by memory elements 210a laminated on the control part 220, an error compensating memory block for providing a substitutive storage area for an error area in each memory block 200, and a main control part for controlling the whole device and correcting an error by a means for encoding or decoding data transmitted/received to/from the external on a substrate. Since the control part 220 is provided with control logic capable of rearranging storage space while evading error areas in respective semiconductor memory elements 210, a highly reliable semiconductor memory medium can be inexpensively constructed by loading defective semiconductor memory elements 210.