Fuji Photo Film Company, Limited

Kenji Moronaga

Mikio Watanabe

Kenji Ito

Osamu Saito

Kaoru Adachi

Kouichi Gouhara

Seiki Nishi

Katsuya Makioka

Nihei Kaname

A digital electronic still-video camera is capable of performing rapid-sequence photography at high speeds. When a rapid-sequence photographic mode has been set, each of a plurality of frames of image data obtained by such photography is compressed. Image data which forms a single multiple-frame picture is constructed by a set of image data composed of the compressed plurality of frames. Thinning out is performed in order to compress the image data. The image data is successively stored, while being thinned out, at corresponding addresses of an image memory in such a manner that a multiple-frame picture is constructed in the image memory. After photography in the rapid-sequence mode ends, the image data in the image memory is subjected to data compression and then recorded on a memory card.

Digital electronic still-video camera, and method of controlling same

A device for coding picture data by compression, and a method thereof. By preprocessing, the device calculates a picture activity of one frame of picture data. A quantizing table circuit selects a particular quantizing step matching the picture activity and sets it in a quantizing circuit 32. On a first path, one frame of picture data is fed to a discrete cosine transform (DCT) circuit to be thereby subjected to orthogonal transform. The quantizing circuit sequentially quantizes DC components, low frequency components and high frequency components of the resulting output of the DCT circuit in ascending order of frequency block by block according to a quantizing step set therein. The picture data from the quantizing circuit are coded by Huffman coding while a code counter counts the coded data. The quantizing step set in the quantizing circuit is updated on the basis of the amount of coded data and a target amount of codes. On a second path, the same one frame of picture data is again fed to the DCT circuit to undergo orthogonal transform and compression, as on the first path. The coded picture data are sent to a memory card or similar picture data storing means. A bit distributing circuit produces a bit distribution value block by block. When the output count of the code counter associated with one block reaches the bit distribution value, the DCT circuit, quantizing circuit and Huffman coding circuit are disenabled while an EOB (End Of Block) code is added to the end of the block of coded picture data.

Picture data compression coding device and method thereof

An electronic still-video camera is provided capable of preserving image data having a quantity which is greater than the storage capacity of a memory cartridge (memory card) loaded in the camera. Besides being capable of receiving an external memory in a memory cartridge loaded in the camera, the camera incorporates an internal memory. Image data obtained as a result of photography is stored in either the internal memory or the external memory, depending upon which memory has been selected by a memory selection switch.

Electronic still-video camera, and playback apparatus therefor being

A device for coding picture data by compression, and a method thereof are provided. By preprocessing, the device calculates a picture activity of one frame of picture data. A quantizing table circuit selects a particular quantizing step matching the picture activity and sets the picture activity in a quantizing circuit. On a first path, one frame of picture data is fed to a discrete cosine transform (DCT) circuit to be thereby subjected to orthogonal transform. The quantizing circuit sequentially quantizes DC components, low frequency components and high frequency components of the resulting output of the DCT circuit in ascending order of frequency block by block according to a quantizing step set therein. The picture data from the quantizing circuit are coded by Huffman coding while a code counter counts the coded data. The quantizing step set in the quantizing circuit is updated on the basis of the amount of coded data and a target amount of codes. On a second path, the same one frame of picture data is again fed to the DCT circuit to undergo orthogonal transform and compression, as on the first path. The coded picture data are sent to a memory card or similar picture data storing medium. A bit distributing circuit produces a bit distribution value block by block. When the output count of the code counter associated with one block reaches the bit distribution value, the DCT circuit, quantizing circuit and Huffman coding circuit are disenabled while an EOB (End of Block) code is added to the end of the block of coded picture data.

A picture recording apparatus includes a first storage having storing units, or clusters, each of which has a predetermined capacity for accommodating video data, and thereby writing video data in the first storage on a cluster basis. An inputting section receives video data to be stored in the first storage. A second storage stores in a predetermined order address data each designating, from among the clusters of the first storage, a particular unoccupied cluster. A controller searches, before writing video data in the first storage, for unoccupied clusters and writes in the second storage first address data which designate clusters necessary for accommodating the video data. A data amount determining section determines the amount of video data outputted by the inputting section and outputs, when the amount of video data matches a single cluster, a first signal for commanding the writing of the video data to the next cluster and a second signal for inhibiting the outputting operation of the inputting section. An address generating section is responsive to the first signal for reading address data representative of the next storing unit out of the second storage, generates a real address on the basis of the address data, and feeds the real address to the first storage. A selecting section selects either one of the output signals of the address generating section and inputting section and selectively feeds either one of the selected output signals and the address data outputted by the controller to the first storage.

Apparatus for recording/reproducing video data in a memory card on a

Electronic still-video camera, and playback apparatus thereof being

An audio/video data reproducing apparatus reads out data from a first storage, which has its storage area equally divided into clusters and stores audio/video data on a cluster-by-cluster basis, to transfer the data read out to utility equipment over a communication path. A second storage stores address data designating clusters of the first storage. Clusters including data to be read out are searched for, and the address data designating the clusters thus searched for is stored in the second storage in a predetermined order. The address data is then sequentially read out from the second storage to generate a real address addressing a storage location of the storage area, which is in turn provided with the real address to develop the stored data in the predetermined order. In response to an error occurring during the transmission on the communication path, the second storage is interrupted from developing the address data therefrom. In response to an amount of the audio/video data corresponding to the capacity of one cluster having been transferred, the second storage develops address data designating another cluster including following data to be read out to generate a real address accordingly. When the clusters associated with the audio/video data already transferred reach in number the clusters searched for, an end-of-read signal is developed.

Audio/video data reproducing apparatus which generates end of data

A device for decoding digital picture data coded by compression to thereby regenerate original picture data has a decoding section for decoding the digital picture data. A reverse normalizing section reversely normalizes picture data outputted by the decoding section. A reverse orthogonal transforming section executes two-dimensional reverse orthogonal transform with picture data outputted by the reverse normalizing section. A data counting section counts coded data existing in a plurality of blocks constituting the digital picture data block by block. A filter selecting section selects an interblock filter and an edge filter on the basis of the amount of coded data determined by the data counting section block by block. A correcting section corrects a distortion between nearby blocks by using the interblock filter selected, while an edge enhancing section executes edge enhancement by using the edge filter. The filter selecting section selects the intensity of the interblock filter and the intensity of the edge filter on the basis of the amount of coded data determined block by block. The filters for the correction of a distortion may be replaced with predicted values which are determined on the basis of the activities of individual blocks and substituted for pixel data. Random noise matching the activities of individual blocks may be added to pixel data after the correction in order to eliminate the distortion of contours of the blocks.

Device for regenerating a picture signal by decoding

A storage management system for a memory card, which has a storage area divided into a plurality of storage units that have a predetermined storage capacity, manages storage of information on a storage unit basis. The storage area includes a MAT for indicating a relationship of ones of the storage units in which a group of mutually associated information is to be stored in the form of a packet, and directory for indicating one of the storage units in which a beginning portion of the packet is to be stored. Stored in one of the storage units is, as a header, management data representative of at least either one of the number of occupied ones of the storage units and the number of idle ones thereof, the header including an error check code for use in detecting an error of the management data.

Storage management system for memory card using memory allocation table

A device for coding a picture signal by compression produces, when detected that the amplitude of data which has undergone two-dimensional orthogonal transform and then normalized has overflown, data specifying the normalized data in addition to coded data of the normalized data. A decoding device, therefore, is capable of accurately decoding original picture data despite the overflow. When a block of picture data lies in a predetermined range which occurs with relatively low probability, the picture data is transformed into coded data which includes a predetermined code. When the block of picture data does not lie in such a range, the picture data is converted into Huffman-coded data. This reduces the required capacity of a look-up table for coding.

Compression coding device and expansion decoding device for picture

A picture data compression coding device sets a normalizing coefficient which matches a block of picture data and normalizes the picture data by the normalizing coefficient, whereby an adequate compression ratio is selected on a block-by-block basis. The coding device sets a normalizing coefficient in response to the sum of activities of individual blocks and normalizes picture data by the normalizing coefficient, thereby maintaining the amount of coded data constant at all times. Further, the coding device normalizes picture data by multiplying them by a reciprocal of the normalizing coefficient so as to eliminate the need for a divider. A decoding device decodes the data having been coded by the coding device.

Compression coding device and expansion decoding device for a picture

A device for coding color picture data by compression maintains compressed data in a predetermined length and prevents the amount of DC signal component data to be allocated from becoming short. A luminance signal and chrominance signals Cr and Cb are compressed independently of each other and recorded as discrete DC components and AC components. When the amount of data of DC components of the chrominance signal Cr or Cb is greater than the total amount of data assigned to the signal Cr or Cb, the amount of data assigned to the signal Cr or Cb is increased to equal the amount of data of DC components of the signal Cr or Cb while the shortage is subtracted from the allocation of AC component data of the luminance signal Y. This insures the allocation of a sufficient amount of data to the coded data of DC components at all times.

Device for coding a picture signal by compression

A picture signal compression coding device is disclosed which divides digital picture data constituting a single picture into a plurality of blocks and codes the picture data block by block by two-dimensional orthogonal transformation. An orthogonal transforming section transforms the digital picture data divided into the plurality of blocks by two-dimensional orthogonal transformation. A normalizing section normalizes the transformed data, while a coding section codes the normalized data. A block activity calculating section calculates an activity of the picture data block by block. An activity summing section sums the block-by-block activities to produce a total activity. A coded data distributing section calculates an amount of coded data to be distributed to each of the blocks on the basis of the ratio of the block-by-block activity to the total activity. A coded output control section limits the amount of coded data to be distributed to each of the blocks from the coding section in response to an output of the coded data distributing section. The block activity calculating section has a subdividing section for subdividing each of the blocks of picture data into a plurality of subblocks, a subblock activity calculating section for calculating the activity of the picture data subblock by subblock, and a difference calculating section for determining a difference between nearby ones of the subblocks with respect to the mean value of subblock-by-subblock picture data.

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Tokyo, Japan

Kenji Moronaga