JP4208122B2 - Data processing apparatus and data processing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a data processing apparatus and method for displaying or distributing data such as a still image and a moving image according to a predetermined procedure for presentation or the like.
[0002]
[Prior art]
  For presentations using materials such as images, graphs, tables, text, and audio, so-called presentation software such as Microsoft PowerPoint (registered trademark) and Apple Keynote (registered trademark) is used. There are many cases. Such presentation software basically edits materials for presentation in advance, for example, by processing various materials into sizes to be displayed and arranging them in the order in which they are to be displayed.
[0003]
  Images are often stored or transmitted in a compressed state. JPEG is widely used for still image compression, and MPEG and Motion-JPEG are widely used for moving image compression. However, JPEG2000 that uses wavelet transform has attracted attention as a new compression method (see, for example, Non-Patent Document 1). .
[0004]
  The compression algorithm of JPEG2000 is defined in the basic specification (ISO / IEC FCD 15444-1). The file format of a JPEG2000 moving image is defined in an extended specification (ISO / IEC FCD 15444-3). In a JPEG 2000 moving image, each frame is compressed as an still image independent of the preceding and following frames by an algorithm defined in the basic specification of JPEG 2000.
[0005]
[Non-Patent Document 1]
Yasuyuki Nomizu, “Next Generation Image Coding System JPEG2000”, Trikes, Inc., February 13, 2001
[0006]
[Problems to be solved by the invention]
  JPEG2000 compressed image data can be decompressed with a resolution, size, image quality, color, etc. that is different from the image before compression, and compressed image data with the resolution, size, image quality, color, etc. changed in the encoded state. Can be converted to
[0007]
  The present invention pays attention to such characteristics of JPEG 2000 compressed image data, and makes it possible to execute various presentations using a data group including JPEG 2000 compressed image data without editing the data in advance. It is an object to provide a data processing apparatus and method.
[0008]
[Means for Solving the Problems]
  A data processing apparatus according to the present invention as described in claim 1,A data processing apparatus for processing JPEG2000 compressed image data (hereinafter simply referred to as compressed image data), the storage means storing the output procedure defining the designation of the data to be output along the time axis and the output conditions; Data acquisition means for capturing predetermined compressed image data in accordance with the designation of data defined in the output procedure, and in the header information of the compressed image data for the captured compressed image data in accordance with the output conditions defined in the output procedure Output data generating means for rewriting the parameter of the predetermined marker segment and generating another compressed image data according to the output condition.
[0009]
  Another feature of the data processing device according to the present invention is that, in the configuration according to claim 1, as described in claim 2,The output data generation means is a marker segment related to a part or all of the resolution, size, image quality, tile position, color, ROI region, and deformation of the image in the header information in accordance with the output condition defined in the output procedure. It is to rewrite the parameters.
[0010]
  Another feature of the data processing device according to the invention is as claimed in claim 3,Claim 1 or 2In the configuration described inThe output data generation means further discards unnecessary codes in the compressed image data in accordance with the output conditions defined in the output procedure.
[0011]
  Another feature of the data processing device according to the invention is as claimed in claim 4,Any one of Claims 1 thru | or 3In the configuration described inThe image processing apparatus further includes decompression means for decompressing the generated compressed image data into image data.
[0012]
  Another feature of the data processing device according to the invention is as claimed in claim 5,Any one of Claims 1 thru | or 3In the configuration described inThe image processing apparatus further includes transmission means for transmitting the generated compressed image data to another apparatus.
[0013]
  The data processing method according to the present invention comprises:Claim 6As described inA data processing method for processing JPEG2000 compressed image data (hereinafter simply referred to as compressed image data) in accordance with an output procedure in which designation of data to be output along a time axis and an output condition are defined, defined in the output procedure A data acquisition step for capturing predetermined compressed image data in accordance with the specified data, and for the captured compressed image data, according to the output conditions defined in the output procedure, the predetermined marker segment in the header information of the compressed image data And an output data generation step of generating another compressed image data according to the output condition by rewriting the parameters.
[0014]
  Another feature of the data processing method according to the present invention is:Claim 7As described inClaim 6In the configuration described inIn the output data generation step, a marker segment related to the resolution, size, image quality, tile position, color, ROI region, or part or all of the deformation of the image in the header information according to the output condition defined in the output procedure It is to rewrite the parameters.
[0015]
  Another feature of the data processing method according to the present invention is:Claim 8As described inClaim 6 or 7In the configuration described inThe output data generation step further includes discarding unnecessary codes in the compressed image data in accordance with the output conditions defined in the output procedure.
[0016]
  Another feature of the data processing method according to the present invention is:Claim 9As described inAny one of claims 6 to 8.In the configuration described inThe method further includes a decompressing step of decompressing the generated compressed image data into image data.
[0017]
  Another feature of the data processing method according to the present invention is:Claim 10As described inAny one of claims 6 to 8.In the configuration described inThe method further includes a transmission step of transmitting the generated compressed image data to another apparatus.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
  In order to facilitate understanding of the following description, JPEG2000 will be outlined.
[0019]
  FIG. 16 is a block diagram for explaining a JPEG2000 compression / decompression algorithm. Image data data to be compressed is divided into non-overlapping rectangular areas (tiles) for each component, and processed in units of tiles for each component. However, it is also possible to process the entire image as one tile.
[0020]
  Each tile image of each component is subjected to color space conversion from RGB data or CMY data to YCrCb data by the color space conversion / inverse conversion unit 1 for the purpose of improving the compression rate. This color space conversion may be omitted.
[0021]
  The tile image after the color space conversion is subjected to a two-dimensional wavelet transform (discrete wavelet transform) by the wavelet transform / inverse transform unit 2 and is decomposed into a plurality of subbands.
[0022]
  FIG. 17 is an explanatory diagram of wavelet transformation when the number of decomposition levels is 3. The tile image (decomposition level 0) shown in FIG. 17A is divided into 1LL, 1HL, 1LH, and 1HH subbands as shown in FIG. 17B by two-dimensional wavelet transform. By applying the two-dimensional wavelet transform to the coefficients of the 1LL subband, the subbands are divided into 2LL, 2HL, 2LH, and 2HH as shown in FIG. By applying the two-dimensional wavelet transform to the coefficients of the 2LL subband, it is divided into 3LL, 3HL, 3LH, and 3HH subbands as shown in FIG. Regarding the relationship between the decomposition level and the resolution level, the numbers shown in parentheses in each subband in FIG. 17D are the resolution levels of the subband.
[0023]
  Wavelet coefficients obtained by recursive division (octave division) of such low frequency components (LL subband coefficients) are quantized for each subband by the quantization / inverse quantization unit 3. In JPEG2000, both lossless (lossless) compression and lossy (lossy) compression are possible. In the case of lossless compression, the quantization step width is always 1, and at this stage, the quantization is not substantially performed.
[0024]
  Each subband coefficient after quantization is entropy encoded by the entropy encoding / decoding unit 4. For this entropy coding, a block-based bit-plane coding method called EBCOT (Embedded Block Coding with Optimized Truncation) consisting of block division, coefficient modeling, and binary arithmetic coding is used. The bit plane of each subband coefficient after quantization is encoded for each block called a code block from the upper bit to the lower bit.
[0025]
  In the tag processing unit 5, the codes of the code blocks generated by the entropy encoding / decoding unit 4 are collected to create a packet, and then the packets are arranged in accordance with the progression order and necessary tags and tag information are added. As a result, encoded data (compressed image data) in a predetermined format is created. In JPEG2000, five types of progression orders are defined with respect to code order control by combinations of resolution level, position (precinct), layer, and component (color component).
[0026]
  The format of JPEG 2000 encoded data generated in this way is shown in FIG. As shown in FIG. 18, the encoded data starts with a tag called an SOC marker indicating the beginning thereof, followed by tag information called a main header (Main Header) describing the encoding parameters, quantization parameters, and the like, After that, the code data for each tile follows. The code data for each tile starts with a tag called an SOT marker, and consists of tag information called a tile header (Tile Header), a tag called an SOD marker, and tile data (Tile Data) containing the code string of each tile. Is done. A tag called an EOC marker indicating the end is placed after the last tile data.
[0027]
  FIG. 19 shows the configuration of the main header. Each marker segment of SIZ, COD, and QCD is essential, but the other marker segments are optional. FIG. 20 shows the configuration of the tile header. 20, (a) shows the structure of the header added to the head of tile data, and (b) shows the header added to the head of the divided tile subsequence when the tile is divided into a plurality of parts. The structure of is shown. There is no mandatory marker segment in the tile header, all are optional. The SOT marker segment configuration is shown in FIG. 21, the SIZ marker segment configuration is shown in FIG. 22, the COD marker segment configuration is shown in FIG. 23, the CRG marker segment configuration is shown in FIG. 24, and the RGN marker segment configuration is shown in FIG. Show.
[0028]
  The decompression process of JPEG 2000 encoded data is the reverse of the compression process. The encoded data is decomposed into a code string of each tile of each component by the tag processing unit 5. This code string is entropy-decoded by the entropy encoding / decoding unit 4. The decoded wavelet coefficients are inversely quantized by the quantization / inverse quantization unit 3 and then subjected to two-dimensional inverse wavelet transform by the wavelet transform / inverse transform unit 2, whereby each tile image of each component is imaged. Is played. Each tile image of each component is subjected to reverse color conversion processing by the color space conversion / inverse conversion unit 1 and returned to a tile image composed of components such as RGB.
[0029]
  In JPEG2000, an image is divided into a plurality of regions, and each divided region is compressed in a state where there is no dependency. However, there are precincts other than the tiles and code blocks as divided regions, and image ≧ tile ≧ There is a size relationship of subband ≧ precinct ≧ code block. A packet is obtained by collecting a part of codes of all code blocks included in the precinct (for example, codes of three bit planes from the most significant bit to the third bit). Packets with an empty code are allowed. The code of the code block is collected to generate a packet, and the encoded data is formed by arranging the packet according to a desired progression order. In FIG. 18, the portion below SOD for each tile is a set of packets.
[0030]
  The encoded data of JPEG2000 can have a layer structure. When packets of all precincts (that is, all code blocks and all subbands) are collected, a part of the code of the entire image (for example, the bits from the most significant bit plane of the wavelet coefficient of the entire image to the third bit) This is a layer. Therefore, the larger the number of layers decoded at the time of decompression, the higher the quality of the reproduced image. That is, a layer can be said to be a unit of image quality. When all layers are collected, it becomes the code of all bit planes of the entire image.
[0031]
  Since the packet constituting the JPEG2000 encoded data described above has the area, image quality, component, and resolution indexes, the code can be selected by the area, image quality, component, and resolution parameters in the code state. is there. That is, a code in which the area, image quality, component, and resolution at the time of reproduction are changed by selectively deleting the code (and rewriting the necessary tag information) without expanding the code data, that is, in the code state. Can be converted into digitized data.
[0032]
  As will be described in detail later, JPEG2000 encoded data is encoded by changing the resolution, image quality, component, and area at the time of reproduction only by rewriting tag information (header information) without changing the code itself. It can also be converted to data.
[0033]
  JPEG2000 has a selective area image quality improvement function (ROI) that lowers the compression ratio of a specific area (increases image quality) without lowering the compression ratio of the entire image. In the basic specification of JPEG2000, an ROI method called a Max Shift method for bit-shifting wavelet coefficients in the ROI region is defined.
[0034]
  FIG. 1 is a block diagram for explaining a first embodiment of the present invention. The data processing apparatus according to this embodiment is configured to generate image data to be displayed on the display device 131, and includes a data acquisition unit 101, an output data generation unit 102, a system control unit 105, and an output procedure file 122. Reference numeral 121 denotes a storage unit for storing the output procedure file 122.
[0035]
  A video memory unit 130 writes image data (output data) generated by the output data generation unit 102, and the image data written therein is displayed on the screen of the display device 131. A data source 120 stores a data group including at least image (still image or moving image) data compressed by JPEG 2000 as a file. The data source 120 is a local storage device or a file server on a network such as a LAN, an intranet, or the Internet.
[0036]
  The system control unit 105 is means for controlling the overall operation of the data processing apparatus. Further, the system control unit 105 takes in and interprets the contents of the output procedure described in the output procedure file 122, and specifies the data specification and output conditions defined along the time axis during the output procedure as data over time. It is also means for notifying the acquisition unit 101 and the output data generation unit 102, respectively.
[0037]
  The data acquisition unit 101 fetches necessary data from the data group stored in one or a plurality of data sources 120 according to the specification of data passed from the system control unit 105 and inputs it to the output data generation unit 102 It is means to do.
[0038]
  The output data generation unit 103 is a unit that generates image data (output data) according to the output conditions passed from the system control unit 105 from the data input from the data acquisition unit 101. The data processing unit 103 and the JPEG2000 It consists of a decoder 104. The JPEG2000 decoder 104 is means for expanding compressed image data by JPEG2000 into image data. The data processing unit 103 passes the compressed image data to the JPEG2000 decoder 104 to expand the image data, expands the text data into image data, and writes the obtained image data to the video memory unit 130. The data processing unit 103 controls the decompression operation of the JPEG2000 decoder 104, rewrites the header information of the compressed image data, scales the decompressed or expanded image data (decimation / interpolation process), and the video memory unit 130 according to the output conditions. Controls the writing position of image data for the.
[0039]
  The output procedure described in the output procedure file 122 defines the designation of data to be output (displayed) along the time axis and the output condition of the data. The data designation is, for example, a file name or URL of the data. As the data output condition, for example, if the data is compressed image data, the conditions directly related to the appearance of the reproduced image, such as the resolution, size, image quality, tile position, color, ROI region, and deformation of the image In addition, the data output (display) time, the position on the screen where the image or text image is displayed, and the like are defined.
[0040]
  FIG. 2 is a simplified flowchart for explaining the operation of the data processing apparatus. Hereinafter, the operation will be described with reference to this flowchart.
[0041]
  First, the system control unit 105 reads an output procedure (step S100). Next, the system control unit 105 analyzes the contents of the output procedure, notifies the data acquisition unit 101 of the designation of the first data, and notifies the output data generation unit 102 of the output condition related to the data. Further, a control procedure related to the data is selected depending on whether or not the type of the data is a moving image (step S102). Here, in order to avoid complication of explanation, explanation will be made on the assumption that the data type is moving picture or still picture data and text data compressed by JPEG2000, but data such as tables, graphs, and voices are excluded. is not.
[0042]
  If the data is a still image or text, the data is fetched from the data source 120 by the data acquisition unit 101 and input to the output data generation unit 102 (step S104).
[0043]
  When the data is text data, the data processing unit 103 develops the image data and writes it into the video memory unit 130. At this time, the size and the writing position (position on the screen) of the image data are determined according to the output conditions. Control is performed (step S106). Then, the system control unit 105 monitors the elapse of the output (display) time designated as the text output condition (step S108).
[0044]
  If the data is compressed still image data, the data is captured by the data acquisition unit 101 and input to the output data generation unit 102 (step S104), and is decompressed to image data by the JPEG2000 decoder 104 of the output data generation unit 102. This is written in the position of the video memory unit 130 designated as the output condition by the data processing unit 103 (step S106). At this time, the data processing unit 103 controls the decompression operation of the JPEG2000 decoder 104 and compresses the compressed image data of each frame in order to generate image data in accordance with the resolution, size, image quality, number of colors, and the like specified as output conditions. The header information is rewritten, the decompressed image data is thinned out / interpolated as necessary (that is, the data processing unit 103 includes means for such control or processing). Will be described later. Then, the system control unit 105 monitors the elapse of the output (display) time designated as the still image output condition (step S108).
[0045]
  If the data is compressed video data, the data of each frame is sequentially taken in by the data acquisition unit 101 and input to the output data generation unit 102 (step S110), and decompressed to image data by the JPEG2000 decoder 104 of the output data generation unit 102. Then, it is written in the position of the video memory unit 130 designated as the output condition by the data processing unit 103 (step S112). At this time, the data processing unit 103 controls the decompression operation of the JPEG2000 decoder 104 and compresses the compressed image data of each frame in order to generate image data in accordance with the resolution, size, image quality, number of colors, and the like specified as output conditions. The header information is rewritten, the decompressed image data is thinned out / interpolated as necessary (that is, the data processing unit 103 includes means for such control or processing). Will be described later. The system control unit 105 monitors the elapse of the output (display) time designated as the moving image output condition (step S114), and repeatedly executes steps S110 and S112 until the output time elapses.
[0046]
  When the output time specified as the output condition has elapsed (step S114 or S108, YES), the system control unit 105 refers to the output procedure and checks whether the next data is specified (step S116). If specified, the same operation is started for the data. When the last data is processed (step S116, NO), the series of output data generation operations is terminated.
[0047]
  Here, regarding the control or processing by the data processing unit 103 for generating image data in accordance with output conditions such as resolution, size, image quality, and color,Specificallyexplain.
[0048]
  In JPEG2000, five progression orders of LRCP, RLCP, RPCL, PCRL, and CPRL are defined. Here, L is a layer, R is a resolution level, C is a component, and P is a precinct.
[0049]
  For example, in the case of RLCP progression, the order of packet placement (compression) or packet interpretation (expansion) can be expressed by the following for loop nested in the order of R, L, C, and P. .
        for (resolution level) {
          for (layer) {
            for (component) {
              for (Precinct) {
                  Place packet: When compressed
                  Interpret packets: when decompressing
          }
        }
      }
    }
[0050]
  In the case of LRCP progression, the order of packet arrangement (when compressed) or packet interpretation (when decompressed) can be expressed by the following for loop nested in the order of L, R, C, and P.
          for (layer) {
          for (resolution level) {
            for (component) {
              for (Precinct) {
                  Place packet: When compressed
                  Interpret packets: when decompressing
          }
        }
      }
    }
[0051]
  In the case of other progression orders, a similar nested for loop determines the arrangement order or interpretation order of packets.
[0052]
  Therefore, in the output data generation unit 102, the resolution of the image data to be decompressed can be adjusted by controlling the number of for-loops of the resolution level of the JPEG2000 decoder 104 by the data processing unit 103. That is, for example, in the case of compressed image data having a number of decomposition levels of 3 as shown in FIG. 17D, when resolution level 0 is specified, only the code of the 3LL subband coefficient is decoded to generate image data, When the resolution level 1 is designated, only the codes of the 3LL, 3HL, 3LH, and 3HH subband coefficients are decoded to generate image data. Similarly, when the resolution level 3 is designated, all subbands from 3LL to 1HH are generated. The coefficient is decoded to generate image data. Similarly, the image quality and the number of colors of the decompressed image data can be adjusted by controlling the number of for loops of the layer and the number of for loops of the component.
[0053]
  The data processing unit 103 includes means for controlling the decompression operation of the JPEG2000 decoder 104 as described above in order to generate image data of resolution, image quality, and number of colors according to the output conditions.
[0054]
  The image size can be adjusted according to the output condition by several methods. For example, a method of performing a scaling process by thinning or interpolation on the image data expanded by the JPEG2000 decoder 104 is possible, and means for that is included in the data processing unit 103. Further, when it is desired to generate image data having a size larger than the image size of the designated resolution level, a dummy subband coefficient (for example, all “0”) having a level higher than the designated resolution level in the decompression process in the JPEG2000 decoder 104 is generated. ) And executing the inverse wavelet transform, image data having a size larger than the specified resolution level can be generated. A means for inserting such dummy subband coefficients is also included in the data processing unit 103. Even in this case, it is natural that scaling processing by thinning / interpolation can be used for final size adjustment.
[0055]
  Further, instead of directly controlling the internal operation of the JPEG2000 decoder 104, the decompression operation of the JPEG2000 decoder 104 can be controlled by rewriting the header information of the compressed image data. Means for the above are also included in the data processing unit 103. A specific example of rewriting the header information will be described below.
[0056]
  (A) Method of changing image resolution and size: The number of decomposition levels is described in SPcod of the COD marker segment (FIG. 23). Rewrite the number of decomposition levels to a smaller value. By this rewriting, the decoder performs expansion only up to the number of decomposition levels after rewriting, so that the reproduced image becomes a low resolution image having a smaller size than the original image.
[0057]
  (B) Simple method for changing image size: In JPEG2000, the position of an image is expressed using coordinate axes called a reference grid. The SIZ marker segment (FIG. 22) in the main header includes parameters Xsiz and Ysiz that describe the horizontal and vertical sizes of the reference grid. The values of Xsiz and Ysiz are rewritten. By this rewriting, a simple image size change can be performed (a part of the image is cut). FIG. 3 schematically shows an example thereof. When the original Xsiz = Ysiz = 5 is rewritten to Xsiz = 3 and Ysiz = 3, the hatched portion of the image to be reproduced as shown in FIG. Played as a small image.
[0058]
  (C) Method of changing tile reproduction position: In the SOT marker segment (FIG. 21) in the tile header, tile numbers (Isot) assigned to the tiles are described in raster order, but the values are rewritten. That is, in the case of an image that has been divided into tiles and compressed as shown in FIG. 4A, by rewriting the tile numbers, for example, the tile arrangement on the reproduced image becomes irregular as shown in FIG. 4B. be able to.
[0059]
  (D) Method of transforming image: The SIZ marker segment (FIG. 22) includes parameters XRsiz (i) and YRsiz (i) in which the number of samples in the horizontal and vertical directions for each component is described. Rewrite this. By this rewriting, the image can be reproduced while being deformed vertically and horizontally. FIG. 5 schematically shows an example thereof. When XRsiz (i) = YRsiz (i) = 2 is set and XRsiz (i) = 1 and YRsiz (i) = 2, the image to be reproduced is as shown in FIG. Is reproduced as an image such as (b) expanded in the horizontal direction, and is reproduced as an image such as (c) contracted in the horizontal direction when rewritten to XRsiz (i) = 4 and YRsiz (i) = 2. The
[0060]
  (E) Another method for deforming an image: In JPEG2000, it is possible to specify a positional deviation (offset) between the origin of the reference grid and the origin of the image. The SIZ marker segment XOsiz and YOsiz are parameters describing horizontal and vertical offsets. The values of XOsiz and YOsiz are rewritten. FIG. 6 schematically shows an example thereof. By rewriting XOsiz = YOsiz = 0 to XOsiz = 3 and YOsiz = 0, the image to be reproduced as shown in FIG. 6A is shifted to the right as shown in FIG. Played with the side missing. It is also possible to use Xsiz and Ysiz together.
[0061]
  (F) Method for preventing reproduction of areas other than the ROI area: As described above, in the basic specification of JPEG2000, the Max Shift method by bit shift is defined as the ROI method. The RGN marker segment (FIG. 25) has a parameter called SPrgn in which the bit shift amount is described. This SPrgn is rewritten to a large value. By this rewriting, only the ROI area can be reproduced. FIG. 7 schematically shows an example thereof. In the case of an image in which the ROI area is shifted by 2 bits as in (a) (that is, SPrgn = 2), SPrgn = 10 (= 2 bits for ROI shift + normal display bits 0 to 7) When rewritten to 8 bits), 8 bits of bits 0 to 7 are not reproduced. Therefore, on the reproduced image, for example, as shown in FIG. 5B, the ROI area is reproduced, but the other areas are not reproduced. When the tile header includes an RGN marker segment, the content has priority over the content of the RGN marker segment in the main header. Therefore, in the encoded data in which the RGN marker segment is included in the tile header, it is necessary to rewrite at least the SPrgn of the RGN marker segment.
[0062]
  (G) Method of always improperly reproducing the color of the image: The COD marker segment (FIG. 23) has a code style parameter SGcod related to the component. This SGcod also describes a value indicating the presence / absence of component color conversion. If this value is 0, there is no color conversion, and if this value is 1, there is color conversion. Rewrite this value. By this rewriting, the image is reproduced with an abnormal color. For example, in encoded data that has undergone color conversion from RGB to YCbCr, the value is set to 1, but when this is rewritten to 0, reverse color conversion is performed to return from YCbCr to RGB upon decompression. Therefore, the color of the reproduced image becomes unnatural. Similarly, when 0 is rewritten to 1, color reproduction becomes unnatural.
[0063]
  (H) Another method of always improperly reproducing the color of an image: The SIZ marker segment (FIG. 22) has a parameter Csiz representing the number of components. An RGB color image or the like is set to Csiz = 3, but this is rewritten to 2. By this rewriting, the image is reproduced as an unnatural color.
[0064]
  (I) Another method for improperly reproducing the color of an image: The CRG marker segment (FIG. 24) includes parameters Xcrg (i) and Ycrg (i) representing horizontal and vertical offset positions for each component. It is. The values of Xcrg (i) and Ycrg (i) are rewritten. By this rewriting, the spatial positional relationship between the components is disturbed, resulting in a reproduction image of an unnatural color in which a so-called color shift occurs.
[0065]
  (J) Change the number of colors of the image: The SIZ marker segment (FIG. 22) has a parameter Csiz representing the number of components. An RGB color image or the like is set to Csiz = 3, but this is rewritten to 1. Thereby, a color image is reproduced as a monochrome image.
[0066]
  Next, a specific example of the output procedure will be described. Although the output procedure can be described in an arbitrary format such as a table format, in this embodiment, in consideration of generality, metadata for multimedia contents whose standardization work is in progress in ISO / IEC JTC1 SC29 / WG11 Is described by the international standard MPEG-7 (Multimedia Content Description Interface; ISO / IEC 15938-1 to 8). This output procedure is saved as an xml file.
[0067]
  An example of an output procedure described in MPEG-7 is shown in FIGS. The contents of the output procedure shown here are as follows.
[0068]
  (1) As data to be output first, sample1. Compressed image data (still image compressed by JPEG2000) stored under the file name jp2 is designated. As output conditions, size = 240 × 360 pixels, resolution = level 1, display position (coordinate of upper left corner of image on screen) = (100, 200), display time = 10 seconds are specified.
[0069]
  (2) The same compressed image data as the first is designated as the second output data. As output conditions, size = 120 × 180 pixels, resolution = level 1, display position = (100, 200), and display time = 10 seconds are designated.
[0070]
  (3) As the third output data, sample2. Compressed image data (moving image compressed by JPEG2000) stored under the file name mj2 is designated. As output conditions, size = 240 × 360 pixels, resolution = level 1, display position = (100, 200), and display time = 10 seconds are designated.
[0071]
  (4) As the last output data, sample3. Text data stored with a file name txt is specified. As output conditions, size = 240 × 360 pixels, display position = (100, 200), and display time = 10 seconds are designated.
[0072]
  Therefore, in this example of the output procedure, an image of 240 × 360 pixel size obtained by first expanding a still image (sample1.jp2) at a resolution level 1 is displayed on the screen of the display device 131 for 10 seconds, and then the same still image is displayed. An image of 120 × 180 pixel size expanded at resolution level 1 is displayed on the screen for 10 seconds, and then an image of 240 × 360 pixel size expanded at resolution level 1 of a moving image (sample2 / mj2) is displayed for 10 seconds. The text (sample3.txt) is displayed on the screen as an image having a size of 240 × 360 pixels for 10 seconds. The display position of each image on the screen is the same.
[0073]
  As is clear from the above description, still images, moving images, and text can be displayed in various forms depending on the contents of the output procedure. For example, by using rewriting of header information as described above, a still image or a moving image is displayed in a state where the tile arrangement is irregular, and the tile arrangement approaches a normal state over time, and finally a normal tile is displayed. By displaying the images side by side, it is possible to realize a display form in which attention is paid to the image. In addition, a display mode that displays still images or moving images with low image quality and low resolution at the beginning, gradually increases the image quality and resolution, displays them halfway in monochrome, and finally displays them in color. it can. In addition, a still image or a moving image can be intentionally displayed in a color-shifted form or displayed in a deformed form. As described above, according to this data processing apparatus, it is possible to make a presentation with a great variety of changes.
[0074]
  As described above, this data processing apparatus displays still images, moving images, texts, and the like stored in the data source 120 in various orders and display forms according to the output procedure without editing them in advance. Therefore, it can be effectively used for presentations.
[0075]
  The function of this data processing apparatus, in other words, the data processing procedure (data processing method) shown in FIG. 2 can be easily realized by a program using computer hardware such as a personal computer. In this case, the JPEG2000 decoder 104 can use a hardware decoder. Such a computer program and various recording (storage) media that can be read by a computer such as a magnetic disk, an optical disk, a magneto-optical disk, and a semiconductor storage element on which the computer program is recorded are also included in the present invention.
[0076]
  FIG. 14 is a block diagram for explaining a second embodiment of the present invention. The data processing apparatus according to this embodiment is configured to generate data for a presentation and distribute it to an external apparatus 240 such as a personal computer, and includes a data acquisition unit 201, an output data generation unit 202, and a system control unit 205. , Output procedure file 222, transmission buffer memory unit 230, and transmission unit 2312. A storage unit 221 stores the output procedure file 222. The contents of the output procedure described in the output procedure file 122 are the same as those in the first embodiment.
[0077]
  The output data generation unit 102 writes the generated output data (transmission data) into the transmission buffer memory unit 230, and the transmission data written therein is transmitted to the personal computer through the interface cable or a network such as a LAN, an intranet, or the Internet by the transmission unit 231. To the external device 131. A data source 220 stores a data group including at least image (still image or moving image) data compressed by JPEG 2000 as a file. The data source 120 is a local storage device or a file server existing on a network such as a LAN, an intranet, or the Internet.
[0078]
  The system control unit 205 is means for controlling the overall operation of the data processing apparatus. In addition, the system control unit 205 captures and analyzes the contents of the output procedure described in the output procedure file 222, and specifies the data designation and output conditions defined along the time axis during the output procedure as data over time. It is also means for notifying the acquisition unit 201 and the output data generation unit 202, respectively.
[0079]
  The data acquisition unit 201 fetches necessary data from the data group stored in one or more data sources 220 in accordance with the data designation notified from the system control unit 205 and inputs it to the output data generation unit 202 It is means to do.
[0080]
  The output data generation unit 203 is a unit that generates output data (transmission data) according to the output condition notified from the system control unit 205 from the data input from the data acquisition unit 201. And a conversion unit 204. The code conversion unit 204 is a means for converting the compressed image data by JPEG 2000 into another compressed image data according to the output condition in the code state. The data processing unit 203 passes the compressed image data to the code conversion unit 204 for conversion, creates transmission data in a predetermined format suitable for transmission from the converted compressed image data and text data, and transmits the transmission data to the transmission buffer memory unit 230. It is a means to write in.
[0081]
  FIG. 15 is a simplified flowchart for explaining the operation of the data processing apparatus. Hereinafter, the operation will be described with reference to this flowchart.
[0082]
  First, the system control unit 205 reads an output procedure (step S200). Next, the system control unit 205 analyzes the output procedure, notifies the data acquisition unit 201 of the designation of the first data, and notifies the output data generation unit 202 of the output conditions related to the data. Further, a control procedure related to the data is selected depending on whether or not the type of the data is a moving image (step S202). Here, description will be made assuming that the data type is moving picture or still picture data compressed by JPEG2000 and text data.
[0083]
  If the data is other than a moving image, that is, a still image or text, the data is fetched from the data source 220 by the data acquisition unit 201 and input to the output data generation unit 202 (step S204).
[0084]
  If the data is text data, the data processing unit 203 creates transmission data containing the text data and writes it in the transmission buffer memory unit 230 (step S206). Each time transmission data is written in the transmission buffer memory unit 230, the transmission data is transmitted to the external device 240 by the transmission unit 231. Then, the system control unit 105 monitors the elapse of the output time specified as the text output condition (step S208).
[0085]
  If the data is compressed still image data, the data is captured by the data acquisition unit 201 and input to the output data generation unit 102 (step S204), and the code conversion unit 204 of the output data generation unit 202 complies with the output conditions. The data is converted into another compressed image data, and the data processing unit 203 creates transmission data containing the converted compressed image data as the content and writes it in the transmission buffer memory unit 230, which is transmitted by the transmission unit 231 ( Step S206). Then, the system control unit 105 monitors the elapse of the output time specified as the still image output condition (step S208).
[0086]
  When the data is compressed video data, the data of each frame is sequentially captured by the data acquisition unit 201 and input to the output data generation unit 202 (step S210), and the output condition is set by the code conversion unit 204 of the output data generation unit 202. Accordingly, the data is converted into another compressed image data, the transmission data is created by the data processing unit 203, written in the transmission buffer memory unit 230, and transmitted by the transmission unit 231 (step S212). The system control unit 205 monitors the elapse of the output time specified as the moving image output condition (step S214), and repeatedly executes steps S210 and S212 until the output time elapses.
[0087]
  When the output time specified as the output condition has elapsed (step S214 or S208, YES), the system control unit 205 refers to the output procedure and checks whether the next data is specified (step S216). If specified, the same operation is started for the data. When the last data has been processed (step S216, NO), the series of operations is terminated.
[0088]
  Here, the code conversion unit 204 will be described. The code conversion unit 204 includes two types of conversion means. As described in the first embodiment, the first conversion means is means for converting the input compressed image data into compressed image data according to the output condition by rewriting the header information. Since this conversion does not handle the code itself, the process is simpler than the conversion by the second conversion means described below.
[0089]
  The second conversion means is means for converting the input compressed image data into compressed image data according to output conditions by discarding unnecessary codes and rewriting necessary header information. For example, when the resolution level is lowered, the second conversion unit generates compressed image data in which packets corresponding to subband coefficients having unnecessary resolution levels are actually discarded. When lowering the image quality, the lower layer packet is discarded in the case of the multi-layer configuration, and the lower bit plane packet is discarded in the case of the single layer configuration. If the color compressed image data is to be converted to monochrome, only the luminance component packet is left, the color difference component packet is discarded, and so on. Since the converted data does not include unnecessary codes, there is an advantage that the amount of transmission data and the transmission time can be reduced.
[0090]
  It should be noted that the conversion by either the first conversion means or the second conversion means is not due to decompression and recompression, and therefore does not cause image quality deterioration due to recompression. In conventional JPEG still image data and Motion-JPEG moving image data, generation-like image quality deterioration due to recompression is inevitable.
[0091]
  When the display position of an image or text on the screen is specified as the output condition and this needs to be transmitted to the external device 240, the data processing unit 203, for example, displays the display position in the header portion of the transmission data. Put the data. In the case of compressed image data, the display position can also be described in the COM (comment) marker segment of the main header. In addition, when it is necessary to transmit the designation of the display size of the text data, it is described in the header portion of the transmission data.
[0092]
  With the above configuration, the external device 240 such as a personal computer expands the received compressed image data into image data, expands the text data into image data, and outputs the image data to the display device. As in the first embodiment, it is possible to perform a display rich in changes in images and text according to the output procedure. Therefore, this data processing apparatus can be effectively used for the purpose of distributing data for presentation or the like to a personal computer or the like.
[0093]
  Note that the functions of the data processing apparatus according to this embodiment, in other words, the data processing procedure (data processing method) shown in FIG. 2 can be easily realized by a program using computer hardware such as a personal computer. . Such a computer program and various recording (storage) media that can be read by a computer such as a magnetic disk, an optical disk, a magneto-optical disk, and a semiconductor storage element on which the computer program is recorded are also included in the present invention.
[0094]
【The invention's effect】
  As described above, the data processing apparatus and method of the present invention areJPEG2000 compressed image dataIt can be displayed in various orders and display forms according to the output procedure without editing in advance, and the data for such display can be distributed to a personal computer, etc., so it is effective for applications such as presentations. Is available.
[Brief description of the drawings]
FIG. 1 is a block diagram for explaining a first embodiment of the present invention.
FIG. 2 is a flowchart for explaining the first embodiment;
FIG. 3 is a diagram for explaining rewriting of header information.
FIG. 4 is a diagram for explaining rewriting of header information.
FIG. 5 is a diagram for explaining rewriting of header information.
FIG. 6 is a diagram for explaining rewriting of header information.
FIG. 7 is a diagram for explaining rewriting of header information.
FIG. 8 is a diagram illustrating an example of an output procedure described in MPEG-7.
FIG. 9 is a diagram showing a continuation of FIG. 8;
FIG. 10 is a diagram showing a continuation of FIG. 9;
FIG. 11 is a diagram showing a continuation of FIG. 10;
FIG. 12 is a diagram showing a continuation of FIG.
FIG. 13 is a diagram showing a continuation of FIG. 12;
FIG. 14 is a block diagram for explaining a second embodiment of the present invention;
FIG. 15 is a flowchart for explaining a second embodiment;
FIG. 16 is a block diagram for explaining an algorithm of JPEG2000.
FIG. 17 is a diagram for explaining wavelet transform;
FIG. 18 is a diagram illustrating a code format of JPEG2000.
FIG. 19 is a diagram for explaining the structure of a main header.
FIG. 20 is a diagram for explaining the structure of a tile header.
FIG. 21 is a diagram showing a structure of an SOT marker segment.
FIG. 22 is a diagram illustrating a structure of an SIZ marker segment.
FIG. 23 is a diagram showing the structure of a COD marker segment.
FIG. 24 is a diagram showing a structure of a CRG marker segment.
FIG. 25 is a diagram showing the structure of an RGN marker segment.
[Explanation of symbols]
  101 Data acquisition unit
  102 Output data generator
  103 Data processing section
  104 JPEG2000 decoder
  105 System control unit
  120 data sources
  122 Output procedure file
  130 Video memory
  131 Display device
  201 Data acquisition unit
  202 Output data generation unit
  203 Data processing unit
  204 Code converter
  205 System control unit
  220 Data Source
  222 Output procedure file
  230 Transmission buffer memory
  231 Transmitter
  240 External device

Claims (10)

A data processing apparatus for processing JPEG 2000 compressed image data (hereinafter simply referred to as compressed image data),
Storage means for storing the output procedure defining the designation of the data to be output along the time axis and the output conditions;
Data acquisition means for capturing predetermined compressed image data in accordance with the designation of data defined in the output procedure;
For the captured compressed image data, according to the output condition defined in the output procedure, the parameter of the predetermined marker segment in the header information of the compressed image data is rewritten, and another compressed image data according to the output condition is Output data generating means for generating;
A data processing apparatus comprising: The output data generation means is a marker segment related to the resolution, size, image quality, tile position, color, ROI region, or part or all of the deformation of the image in the header information in accordance with the output condition defined in the output procedure. The data processing apparatus according to claim 1, wherein the parameter is rewritten. 3. The data processing apparatus according to claim 1, wherein the output data generation unit discards unnecessary codes in the compressed image data in accordance with output conditions defined in the output procedure. 4. The data processing apparatus according to claim 1, further comprising decompression means for decompressing the generated compressed image data into image data. 4. The data processing apparatus according to claim 1, further comprising a transmission unit configured to transmit the generated compressed image data to another apparatus. 5. A data processing method for processing JPEG2000 compressed image data (hereinafter simply referred to as compressed image data) according to an output procedure that defines the designation of data to be output along a time axis and output conditions
A data acquisition step for capturing predetermined compressed image data in accordance with the designation of data defined in the output procedure;
For the captured compressed image data, according to the output condition defined in the output procedure, the parameter of the predetermined marker segment in the header information of the compressed image data is rewritten, and another compressed image data according to the output condition is An output data generation step to generate;
A data processing method characterized by comprising: The output data generation step includes marker segments related to the resolution, size, image quality, tile position, color, ROI region, and part or all of deformation in the header information in accordance with the output conditions defined in the output procedure. The data processing method according to claim 6, wherein the parameter is rewritten. 8. The data processing method according to claim 6, wherein the output data generation step further discards unnecessary codes in the compressed image data in accordance with output conditions defined in the output procedure. The data processing method according to claim 6, further comprising a decompressing step of decompressing the generated compressed image data into image data. 9. The data processing method according to claim 6, further comprising a transmission step of transmitting the generated compressed image data to another device.

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