JP2006203804A - Image processing device, image processing method, program, and information storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To produce a decoded image having good image quality as much as possible, and to improve process efficiency by neglecting waste entropy decoding process, even when a code which cannot be decoded normally is to be included in coding data. <P>SOLUTION: In the preparation step of a decoding process, an error flag list for managing a state of entropy decoding of the code in every attribute such as an area, resolution, image quality, color components, etc. is to be produced (S3). The entropy decoding of the code having an attribute which is to be determined as "abnormal" in the error flag list is to be inhibited (S5), and only the code having an attribute which is to be determined as not abnormal is entropy decoded (S6). If the entropy decoding is determined as abnormal, correction needed for the error flag list is to be performed (S7, S8). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus and method for performing decoding processing of encoded data of an image, and in particular, JPEG2000 still image encoding in which codes constituting encoded data have attributes such as area, resolution, color component, and image quality. The present invention relates to an apparatus and a method for decoding data, Motion-JPEG2000 moving image encoded data, and the like.

  The encoded data of still images or moving images captured via the network may include codes that cannot be decoded due to network transmission errors. In addition, even encoded data acquired via a network or encoded data acquired from a local storage device or the like without via a network cannot be decoded due to the decoding capability of the decoding device. A sign may be included.

  Generally, in an apparatus that performs decoding processing of encoded data, if the encoded data includes an abnormal code or a code that cannot be decoded, the decoding process is stopped and the code is generated up to that point. A control method for outputting an image and a control method for abandoning image formation itself have been used.

  Patent Document 1 is an example of a publicly known document relating to such control. In a server / client system that handles JPEG2000 still image encoded data or Motion-JPEG2000 moving image encoded data described therein, each packet is deleted at the time of encoding processing on the server side. The amount of distortion of the restored image is estimated, and information on the estimated amount of distortion is recorded in the main header of the encoded data. On the client side, the encoded data received from the server is decoded and the decoded image is progressively displayed. The packet error is detected by analyzing the packet, and the distortion amount related to the error packet (recorded in the main header). ) Is calculated, the amount of distortion of the decoded image due to the error packet at each time point is calculated, and when the amount of distortion exceeds a threshold value, the decoding process and the output of the decoded image data are stopped.

JP 2004-186858 A

  There is room for improvement in the method of stopping the decoding process when an abnormal code or a code that cannot be decoded occurs. In the case of encoded data obtained by dividing an image into a plurality of regions and encoding them, the code in a certain region cannot be decoded, and even the code in another region is decoded. Since it is not always impossible, it is more likely that the image quality of the restored image can be improved by continuing the decoding process for a code in a region where there is no problem instead of stopping the decoding process.

  It is clear that there is a similar room for improvement in the method of stopping the decoding process when the distortion amount of the decoded image due to the error packet exceeds the threshold value. In addition, this method requires that the amount of distortion for each packet be estimated at the encoding stage and described in the header of the encoded data, and is applicable to encoded data without such description. There is also a restriction that it cannot.

  The present invention has been made in view of the problems of the prior art as described above. The main object of the present invention is to prevent normal decoding of encoded data in an apparatus or method for decoding encoded data. The purpose is to improve the decoded image quality and the processing efficiency when possible codes are included.

  Note that in the present invention, encoded data composed of a collection of codes having an attribute relating to at least one of area, color component, resolution, and image quality is handled. Typical examples of such encoded data include JPEG 2000 still image encoded data and Motion-JPEG 2000 moving image encoded data.

  The invention according to claim 1 is an image processing apparatus including a decoding processing device that performs decoding processing of encoded data of an image, which includes a code having an area attribute, and the code in the encoded data in the decoding processing device Control that controls the state of entropy decoding for each region, and suppresses entropy decoding of the following code having the attribute of the certain region when an abnormality occurs in the entropy decoding of the code having the attribute of the certain region An image processing apparatus having means.

  The invention according to claim 2 is an image processing apparatus including a decoding processing device that performs decoding processing of encoded data of an image, which includes a code having an attribute of a color component, in the encoded data in the decoding processing device Manages the state of code entropy decoding for each color component, and suppresses entropy decoding of a subsequent code having a certain color component attribute when an abnormality occurs in the entropy decoding of the code having a certain color component attribute An image processing apparatus having control means for performing control.

  According to a third aspect of the present invention, there is provided an image processing apparatus including a decoding processing device that performs decoding processing of encoded data of an image, which includes a code having a resolution attribute, and the code in the encoded data in the decoding processing device Control that controls the state of entropy decoding for each resolution, and controls to suppress entropy decoding of subsequent codes having a certain resolution attribute when an abnormality occurs in entropy decoding of a code having a certain resolution attribute An image processing apparatus having means.

  According to a fourth aspect of the present invention, there is provided an image processing apparatus including a decoding processing device that performs decoding processing of encoded data of an image, which includes a code having a resolution attribute, and the code in the encoded data in the decoding processing device The entropy decoding state is managed for each resolution, and when an error occurs in the entropy decoding of a code having a certain resolution attribute, a subsequent code having the certain resolution attribute and an attribute having a higher resolution than the certain resolution are displayed. An image processing apparatus comprising: a control unit that performs control to suppress entropy decoding of a subsequent code.

  According to a fifth aspect of the present invention, there is provided an image processing apparatus including a decoding processing device that performs decoding processing of encoded data of an image, which includes a code having an attribute of image quality, and the code in the encoded data in the decoding processing device Control that controls the state of entropy decoding for each image quality, and controls to suppress entropy decoding of subsequent codes with certain image quality attributes when an abnormality occurs in entropy decoding of codes with certain image quality attributes An image processing apparatus having means.

  The invention according to claim 6 is an image processing apparatus including a decoding processing device that performs decoding processing of encoded data of an image, which includes a code having an attribute of image quality, and the code in the encoded data in the decoding processing device The entropy decoding state of each image quality is managed for each image quality, and when an error occurs in the entropy decoding of a code having a certain image quality attribute, a subsequent code having the certain image quality attribute and an attribute having a higher image quality than the certain image quality An image processing apparatus comprising: a control unit that performs control to suppress entropy decoding of a subsequent code.

  A seventh aspect of the present invention is the image processing apparatus according to any one of the first to sixth aspects, wherein the control means suppresses entropy decoding in the image restoration processing in the decoding processing apparatus. An image processing apparatus that controls whether or not to use decoded data having a code having the same attribute as the code.

  The invention according to claim 8 is the image processing apparatus according to any one of claims 1 to 6, wherein encoded data of an image is fetched from an external apparatus and is decoded by the decoding processing apparatus. A code storage device for storing the encoded data decoded by the processing device, wherein the control means suppresses entropy decoding in the encoded data stored in the code storage device in the decoding processing device; An image processing apparatus that controls whether or not to include a code having the same attribute as the code.

  The invention described in claim 9 is a program that causes a computer to function as the decoding processing apparatus and control means according to any one of claims 1 to 8.

  A tenth aspect of the present invention is a computer-readable information recording medium in which a program that causes a computer to function as the decoding processing device and the control means according to any one of the first to eighth aspects of the invention is recorded. .

  The invention according to claim 11 has a decoding process step for decoding encoded data of an image composed of codes having region attributes, and this decoding process step is for entropy decoding of codes in encoded data. Including a control process for managing the state for each area and performing control to suppress entropy decoding of a subsequent code having the attribute of the certain area when an abnormality occurs in the entropy decoding of the code having the attribute of the certain area An image processing method characterized by the above.

  The invention described in claim 12 has a decoding process step for decoding encoded data of an image consisting of a code having a color component attribute, and the decoding process step includes entropy decoding of a code in the encoded data. Control for each color component, and when an error occurs in entropy decoding of a code having an attribute of a certain color component, control for suppressing entropy decoding of a subsequent code having the attribute of the certain color component It is an image processing method characterized by including a process.

  The invention described in claim 13 has a decoding process step for decoding encoded data of an image consisting of a code having a resolution attribute, and this decoding process step is for entropy decoding of the code in the encoded data. Including a control process for managing the state for each resolution and performing control to suppress entropy decoding of a subsequent code having a certain resolution attribute when an abnormality occurs in the entropy decoding of the code having a certain resolution attribute An image processing method characterized by the above.

  The invention according to claim 14 has a decoding process step for decoding encoded data of an image consisting of a code having a resolution attribute, and the decoding process step is for entropy decoding of the code in the encoded data. The status is managed for each resolution, and when an error occurs in entropy decoding of a code having a certain resolution attribute, a subsequent code having a certain resolution attribute and a subsequent code having a higher resolution attribute than the certain resolution It is an image processing method characterized by including the control process which performs control which suppresses entropy decoding of.

  The invention described in claim 15 has a decoding process step for decoding encoded data of an image consisting of a code having an image quality attribute, and this decoding process step is for entropy decoding of the code in the encoded data. Including a control step of managing the state for each image quality and performing control to suppress entropy decoding of a subsequent code having a certain image quality attribute when an abnormality occurs in the entropy decoding of the code having a certain image quality attribute An image processing method characterized by the above.

  The invention described in claim 16 has a decoding process step of decoding encoded data of an image consisting of a code having an image quality attribute, and this decoding process step is for entropy decoding of the code in the encoded data. The state is managed for each image quality, and when an error occurs in the entropy decoding of a code having a certain image quality attribute, the subsequent code having the certain image quality attribute and the subsequent code having an image quality attribute higher than the certain image quality It is an image processing method characterized by including the control process which performs control which suppresses entropy decoding of.

  The invention according to claim 17 is the image processing method according to any one of claims 11 to 16, wherein the control step suppresses entropy decoding in the image restoration processing in the decoding processing step. This is an image processing method characterized by controlling whether or not to use decoded data having a code having the same attribute as the code.

  The invention according to claim 18 is the image processing method according to any one of claims 11 to 16, wherein the encoded data for storing the encoded data decoded by the decoding processing step is provided. Whether or not to include a code having the same attribute as the code whose entropy decoding is suppressed in the decoding process step in the encoded data stored in the encoded data storage step. An image processing method characterized by performing control.

  According to the first and eleventh aspects of the present invention, when an abnormality in entropy decoding of a code having an attribute of a certain region occurs, the decoded image quality deteriorates for that region, but the decoded image quality decreases for other regions. Therefore, the overall image quality of the decoded image is improved as compared with the method of canceling the decoding process. Also, even if entropy decoding is performed on a subsequent code having the same region attribute as that of the code in which the entropy decoding abnormality has occurred, it is normal to expect little contribution to the improvement of the decoded image quality, which is a useless process. However, it is possible to obtain an effect of improving processing efficiency by suppressing such useless entropy decoding.

  According to the second and twelfth aspects of the present invention, when an entropy decoding abnormality of a code having an attribute of a certain color component occurs, the decoded image quality deteriorates for that color component, but decoding is performed for other color components. Since the image quality does not deteriorate, the overall image quality of the decoded image is improved as compared with the method of canceling the decoding process. In addition, even if entropy decoding is performed on a subsequent code having the same color component attribute as that of the code in which the entropy decoding abnormality has occurred, it is normal to expect little contribution to the improvement of the decoded image quality, which is a useless process. However, it is possible to obtain an effect of improving processing efficiency by suppressing such useless entropy decoding.

  According to the third, fourth, thirteenth and fourteenth aspects of the present invention, when an entropy decoding error occurs in a code having a certain resolution attribute, the entropy decoding is suppressed in the subsequent processes having the resolution attribute. Since it is a code, or a subsequent code having a resolution attribute and a subsequent code having a higher resolution attribute, the decoded image quality is higher than the method of stopping the decoding process at the stage of the code where the abnormality occurred. There is an effect that can be obtained. In addition, a code for which entropy decoding is suppressed can hardly be expected to contribute to the improvement of the decoded image quality even if the entropy decoding is performed, which can be said to be a useless process. By suppressing the entropy decoding, an effect of improving the processing efficiency can be obtained.

  According to the fifth, sixth, fifteenth and sixteenth aspects of the present invention, when an entropy decoding abnormality having a certain image quality attribute occurs, the entropy decoding is suppressed by a subsequent code having the image quality attribute, Alternatively, since a subsequent code having the image quality attribute and a subsequent code having a higher image quality attribute are obtained, a higher decoding image quality is obtained as compared with the method in which the decoding process is stopped at the stage of the code where the abnormality has occurred. There is an effect that can be. In addition, a code for which entropy decoding is suppressed can hardly be expected to contribute to the improvement of the decoded image quality even if the entropy decoding is performed, which can be said to be a useless process. By suppressing the entropy decoding, an effect of improving the processing efficiency can be obtained.

  According to the seventh and seventeenth aspects of the present invention, image restoration that does not use the decoded data of the code having the same attribute as the code in which the entropy decoding abnormality has occurred and the same attribute as the code in which the entropy decoding abnormality has occurred. Even if it is a code | cord | chord, the effect that the image restoration which uses also the decoding data of the code | cord | chord which has been decoded before entropy decoding is suppressed can be acquired. For example, if an abnormality in entropy decoding of a code in a certain region occurs, if the former image restoration is selected, the image is not restored for that region, but if the latter image restoration is selected, the decoded code of that region is also restored. It is possible to restore an image with an image quality according to the degree.

  According to the inventions of claims 8 and 18, it is possible to store the same encoded data as that acquired from an external device, including a code having the same attribute as the code for which entropy decoding is suppressed. It is possible to save encoded data that does not include codes having attributes.

[Outline of JPEG2000]
In the embodiment of the present invention described here, JPEG 2000 still image encoded data or Motion-JPEG 2000 moving image encoded data is a processing target. Each frame of Motion-JPEG2000 moving image encoded data is encoded by JPEG2000. Therefore, an outline of JPEG2000 will be described to the extent necessary for understanding the embodiment of the present invention.

  FIG. 1 is a block diagram for explaining the algorithm of JPEG2000. In the figure, 1 is a color space transformation / inverse transformation unit, 2 is a two-dimensional wavelet transformation / inverse transformation unit, 3 is a quantization / inverse quantization unit, 4 is an entropy encoding / decoding unit, and 5 is a tag processing unit. is there.

  At the time of encoding (compression), each component (color component) of the original image is divided into non-overlapping rectangular areas called tiles as necessary, and the data of each tile of each component is color space conversion / inverse conversion unit 1. Is input.

  FIG. 2 shows an example of tile division. In this example, the R, G, and B components of the original image are each divided into 16 tiles. Each tile of each component is a compression / decompression processing unit.

  Each tile of each component is converted into the YCrCb (or YUV) color system by the color space conversion / inverse conversion unit 1 and then converted into a two-dimensional wavelet transform (in the two-dimensional wavelet conversion / inverse conversion unit 2) for each component of YCrCb. By applying (forward transformation), space division is performed into frequency bands (subbands).

  FIG. 3 shows subbands at each decomposition level when the number of decomposition levels = 3. That is, by performing two-dimensional wavelet transform on the tile image (0LL) (decomposition level 0) obtained by tile division of the original image, the subbands (1LL, 1HL, 1LH, 1HH) at the composition level 1 are applied. ) Is obtained. By applying a two-dimensional wavelet transform to the coefficients of the 1LL subband, which is a low frequency component in this hierarchy, subbands (2LL, 2HL, 2LH, 2HH) of composition level 2 are obtained. By applying a two-dimensional wavelet transform to the 2LL subband coefficient which is a low frequency component in this hierarchy, a subband (3LL, 3HL, 3LH, 3HH) at a composition level 3 is obtained. The numbers in parentheses in each subband at decomposition level 3 indicate the resolution level.

  The coefficients of each subband are linearly quantized by the quantization / inverse quantization unit 3 as necessary, and then entropy-coded by the entropy coding / decoding unit 4. In JPEG2000, each subband coefficient is divided into bit planes, each subband is divided into non-overlapping rectangular areas called precincts, and each precinct is divided into non-overlapping rectangular areas called code blocks. The coefficients of each subband are encoded for each code block from the upper bitplane to the lower bitplane (more precisely, each bitplane is divided into three subbitplanes (encoding passes). And encoded). In this entropy encoding, the encoding target bits are determined in the designated encoding order, and a context is generated from the peripheral bits of the target bits by the quantization unit / inverse quantization unit 3, and the probability of the context and the target bit is determined. Arithmetic coding by estimation is performed.

  The tag processing unit 5 is a block of a code formation process, generates packets by collecting entropy codes, arranges packets according to a progression order, adds necessary tags and tag information, and has a format as shown in FIG. One code stream (encoded data) is generated. Tag information called a main header (Tile-part header) and a tile part header (Tile-part header) is added to the head of the code stream and the head of each tile part, and then the code (bit stream) of each tile follows. An end tag (End of codestream) is placed at the end of the codestream.

Among images, tiles, subbands, precincts, and code blocks, there is a size relationship of image ≧ tile> subband ≧ precinct ≧ code block.

  A precinct is a rectangular region of subbands, and a set of three regions at the same spatial position of HL, LH, and HH subbands having the same decomposition level is treated as one precinct. However, in the LL subband, one area is treated as one precinct. It is also possible to make the precinct size the same as the subband. As described above, the rectangular area obtained by dividing the precinct is a code block. FIG. 5 illustrates a precinct and its code block at decomposition level 2. A set of three regions at the same spatial position indicated as precinct in the figure is treated as one precinct. The precinct corresponds to a specific rectangular area on the tile image. That is, in the example shown in FIG. 5, the tile image is divided into 3 × 3 rectangular areas, and the rectangular areas can be said to be precincts.

  A packet is a collection of a part of the 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 bit stream in FIG. 4 is a packet in which codes of code blocks are combined to generate packets and the packets are arranged according to a desired progression order.

  When packets of all precincts (that is, all code blocks and all subbands) are collected, a part of the code for the entire image area (for example, the bits from the most significant bit plane to the third frame of the wavelet coefficients for the entire image area) This is a layer (however, not all precinct packets need to be included in the layer). Therefore, as the number of layers decoded at the time of expansion increases, the quality of the reproduced image improves. That is, a layer is a unit of image quality. When all layers are collected, it becomes the code of all bit planes of the entire image.

  FIG. 6 shows an example of packets and layers when tile division is not performed and the number of components = 1 and the number of decomposition levels = 2 (the number of resolution levels = 3). In the figure, a vertically small rectangle is a packet, and the numbers shown therein are packet numbers assigned for convenience. In FIG. 6, the layer is shown as a horizontally long rectangular region with shading. That is, in this example, layer 0 consisting of the code of the packet number 0-16, layer 1 consisting of the code of the packet number 17-33, layer 2, consisting of the code of the packet number 34-50, packet number From layer 3 consisting of codes of packets 51 to 67, layer 4 consisting of codes of packets of packet numbers 68 to 84, layer 5 consisting of codes of packets of packet numbers 85 to 101, and codes of packets of packet numbers 102 to 118 Layer 6 consisting of codes of packets with packet numbers 119 to 135, layer 8 consisting of codes of packets with packet numbers 136 to 148, and layer 9 consisting of codes of packets with the remaining packet numbers 149 to 161 It is divided into 10 layers. Note that the correspondence between packets and precincts changes variously depending on the difference in progression order, the number of layer divisions, etc., and the layer configuration shown above is merely an example.

  On the other hand, at the time of decoding (decompression), image data is generated from the code stream of each tile of each component, contrary to the case of encoding. In this case, the tag processing unit 5 interprets tag information added to the code stream input from the outside, decomposes the code stream into code streams of each tile of each component, and each code stream of each tile of each component. The decryption process is performed. The positions of the bits to be decoded are determined in the order based on the tag information in the codestream, and the quantization / inverse quantization unit 3 arranges the peripheral bits (the decoding has already been completed) at the target bit position. A context is created from The entropy encoding / decoding unit 4 performs decoding based on probability estimation from the context and the code stream to generate a target bit, and writes it in the position of the target bit.

  The coefficients of the subbands thus obtained are dequantized by the quantization / inverse quantization unit 3 if quantization is performed at the time of encoding, and then the two-dimensional wavelet transform / inverse transform unit. By performing the two-dimensional wavelet inverse transform in 2, the data of each tile of each component is restored. If color space conversion is performed at the time of encoding, the restored data is subjected to reverse color conversion by the color space conversion / inverse conversion unit 1 and returned to the original color system data.

Now, as mentioned above, JPEG2000 code unit packet is
Which component (symbol C) belongs to,
Which resolution level (symbol R) belongs to
Which precinct (symbol P) belongs to
It has four attributes, which layer (symbol L) belongs to. The packet arrangement means the order in which packets are arranged hierarchically. This order of arrangement is called a progression order. JPEG2000 defines five progression orders of LRCP, RLCP, RPCL, PCRL, and CPRL.

  Here, a state in which packets are arranged in the order of the progression order at the time of encoding and a state in which the attributes of the packets are interpreted in the order of the progression order at the time of decoding will be described.

For LRCP progression, nested for loops
for (layer) {
for (resolution) {
for (component) {
for (Precinct) {
Encoding: Place packet
Decoding: Interpret packet attributes}
}
}
}
Thus, the packet is arranged (at the time of encoding) and interpreted (at the time of decoding).

Similarly, for RLCP progression, a nested for loop
for (resolution) {
for (layer) {
for (component) {
for (Precinct) {
Encoding: Place packet
Decoding: Interpret packet attributes}
}
}
}
Thus, the packet is arranged (at the time of encoding) and interpreted (at the time of decoding).

Each packet has a packet header,
-Whether the packet is empty-Which code block is included in the packet-Number of zero bit planes of each code block included in the packet-Number of coding passes (number of bit planes) of each code block code included in the packet )
-The code length of each code block included in the packet is described.

  However, the packet header does not describe any layer number or resolution level. At the time of decoding, a for loop as described above is formed from the progression order described in the COD marker in the main header, and a packet break is determined from the sum of the code lengths of the code blocks included in the packet. Depending on which position in the for loop is handled, it can be known which resolution level of which layer each packet is. This means that the next packet can be detected without decoding the entropy code itself as long as the code length in the packet header is read.

When tiled to two or more tiles, the packet also has an attribute of which tile it belongs to. So if you add the tile attribute, the for loop above will
for (tile) {
for (layer) {
for (resolution) {
for (component) {
for (Precinct) {
Encoding: Place packet
Decoding: Interpret packet attributes}
}
}
}
}
It becomes a loop like this.

  FIG. 7 shows a packet arrangement example of LRCP progression when the image size is 100 × 100 pixels, 1 tile, 2 layers, resolution level 3 (0 to 2), 3 components, and the precinct size is 32 × 32. An example of the arrangement of packets of RPCL progression is shown in FIG.

[Description of Embodiment]
Embodiments of the present invention will be described below. FIG. 9 is a block diagram for explaining an embodiment of the present invention. In FIG. 9, reference numeral 100 denotes an image processing apparatus according to the present invention, which can operate alone or operate as a client with respect to a server 102 connected via a communication path 101 (such as a LAN or the Internet). is there.

  The image processing apparatus 100 communicates with a decoding processing apparatus 110 that performs decoding processing of JPEG2000 still image encoded data or Motion-JPEG2000 moving image encoded data, an image display apparatus 111 that displays decoded images, and the server 102. The communication device 112 includes a code storage device 113 for storing encoded data, an instruction input device 114 for inputting various instructions from the user, and a system control device 115 for controlling the operation of the entire device.

  The decoding processing device 110 includes a tag processing unit 121, an entropy decoding unit 122, an inverse quantization unit 123, a two-dimensional inverse wavelet transform unit 124, and an inverse color space transform unit 125 as described with reference to FIG. A control unit 126 that controls each unit, a data storage unit 127 that temporarily stores data related to the decoding process, and an interface 128 with other parts of the image processing apparatus 100 are configured.

  Control of entropy decoding state, decoding processing, and code storage unique to the present invention is performed by the control unit 126. That is, the control means according to the first to eighth aspects of the present invention is included in the control unit 126. For such control, an error flag list 130 (described later) is generated / corrected. The data storage unit 127 is used as a storage area for the error list 130.

<Description of operation (1)>
An operation of reading encoded data of an image designated by the user using the instruction input device 114 from the code storage unit 113 to the decoding processing device 110 and performing decoding processing, and displaying the decoded image on the image display device 111 will be described. FIG. 10 is a simplified flowchart for the explanation.

  First, the tag processing unit 121 analyzes the main header (and the first tile part header) of the encoded data (step S1). By this analysis, information such as the tile size, the number of tiles, the precinct size, the progression order, the number of resolution levels, the number of layers, the number of components, and the like can be obtained. Based on the analysis result, the control unit 126 sets various parameters related to the decoding process (step S2). Up to this point, the operation is the same as that of a general decoding processing apparatus. Interpretation of packet attributes and entropy decoding are performed according to the for loop as described above corresponding to the progression order. This for loop is also set at this stage. Although simplified in FIG. 10, the processes in steps S4 to S8 are such repeated processes in the for loop. The analysis of the second and subsequent tile part headers is performed at any time in the processes after step S4, and necessary parameter setting changes and the like according to the analysis results are performed.

  Next, the control unit 126 creates an error flag list based on an instruction from the instruction input device 114 (step S3). This error flag list is management information for managing entropy decoding status and decoding processing control for each attribute such as area (tile, precinct, etc.), resolution, image quality (layer), component (color component), and the like.

  For example, when a tile is designated as an attribute, an error flag list as shown in FIG. In the figure, the error state value “0” represents a normal state, and “1” represents an abnormal state. Normally, the error state of all tiles is set to “0” as shown in FIG. 11A in the initial stage, but by intentionally setting the error state of a specific tile to “1”, the tiles It is also possible not to perform the decoding process.

  When entropy decoding state management and decoding processing control based on more detailed region attributes are designated, a similar error flag list is created in units of precincts or code blocks. When the tile is divided into two or more tiles, such an error flag list is created for each tile.

  When entropy decoding state management, decoding processing control, and the like are designated by the layer (image quality) attribute, an error flag list as shown in FIG. 12A is created, for example. When divided into two or more tiles, such an error flag list is created for each tile or only one for all tiles. In the former case, management of entropy decoding state and decoding processing control by layer attribute are performed separately for each tile, and in the latter case, common entropy decoding state management and decoding processing control for all tiles are performed. Done. Normally, in the initial stage, the error state of all layers is set to “0” as shown in FIG. 12A, but by intentionally initializing the error state of a specific layer to “1”, It is also possible not to perform layer decoding processing.

  When management of the entropy decoding state based on the resolution attribute and decoding processing control are designated, an error flag list as shown in FIG. 13A is created, for example. When divided into two or more tiles, such an error flag list is created for each tile or only one for all tiles. In the former case, management of entropy decoding state and resolution processing control by resolution attribute are performed separately for each tile, and in the latter case, management of entropy decoding state and decoding processing control are common to all tiles. Done. Normally, at the initial stage, as shown in FIG. 13A, error states of all resolution levels are set to “0”, but an error state of a specific resolution level is intentionally initialized to “1”. Thus, it is possible not to perform the decoding process at that resolution level.

  When entropy decoding state management, decoding processing control, and the like are specified by component (color component) attributes, an error flag list as shown in FIG. 14A is created, for example. When divided into two or more tiles, such an error flag list is created for each tile or only one for all tiles. In the former case, decoding processing control and the like based on component attributes are performed separately for each tile, and in the latter case, common decoding processing control and the like are performed for all tiles. Normally, at the initial stage, as shown in FIG. 14A, the error states of all the color components are set to “0”, but the error state of a specific component is intentionally initialized to “1”. Therefore, it is possible not to perform the decoding process of the component.

  It is also possible to manage entropy decoding status and control decoding processing by region (tile, precinct, code block) attribute, layer attribute, or resolution attribute for each component. In this case, an error flag list based on these attributes is created for each component.

  After the above preparation processing, the processing in steps S4 to S8 is performed while reading the code in the encoded data in units of packets.

  First, the control unit 126 refers to the error flag list and checks an error state corresponding to the attribute of the read packet (step S5). If the error state is “1”, the control unit 126 controls the entropy decoding unit 122 to read the next packet without performing entropy decoding on the packet. That is, a packet having an attribute whose error state is “1” is skipped.

  On the other hand, if the error state corresponding to the attribute of the packet is “0”, the control unit 122 causes the entropy decoding unit 122 to perform entropy decoding of the packet (step S6). The decoded data (wavelet coefficient) is stored in the data storage unit 127. The control unit 126 checks whether the entropy decoding of the packet has been performed normally (step S7), and performs control to read the next packet if it is normal.

  If an abnormality occurs in the entropy decoding of the packet, the control unit 126 performs necessary correction of the error flag list (step S8), and then performs control to read the next packet. The error flag list correction will be described with reference to FIGS.

  For example, when entropy decoding status management and decoding processing control are performed using tile attributes, for example, when an entropy decoding abnormality of a packet belonging to tile 2 occurs, tiles in the error flag list as shown in FIG. The error state of 2 is corrected to “1”. As a result, all subsequent packets included in the tile 2 are skipped.

  When entropy decoding state management and decoding processing control are performed by layer attributes, for example, when an entropy decoding abnormality of a packet belonging to layer 6 occurs, layer 6 of the error flag list as shown in FIG. And the error state of the lower layers 7 to 9 is corrected to “1”. As a result, all subsequent packets belonging to layers 6 to 9 are skipped. It is also possible to correct the error state to “1” only for layer 6 where the entropy decoding abnormality has occurred, and to leave the error state of the lower layers as “0”. Included in the form.

  In the case where entropy decoding state management and decoding processing control by the resolution attribute are performed, for example, when an entropy decoding abnormality of a packet belonging to resolution level 4 occurs, the resolution of the error flag list as shown in FIG. The error condition of level 4 and lower resolution level 5 is corrected to “1”. As a result, all subsequent packets belonging to the resolution levels 4 and 5 are skipped. Note that it is also possible to correct the error state to “1” only at the resolution level 4 in which the entropy decoding abnormality has occurred, and to leave the error state at the lower resolution level 5 as “0”. It is included in this embodiment.

  When entropy decoding state management and decoding processing control are performed using component (color component) attributes, for example, when an entropy decoding abnormality of a Cb component packet occurs, an error flag list as shown in FIG. The error state of the Cb component is corrected to “1”. As a result, the subsequent Cb component packets are skipped, but the Y component and Cr component packets whose error state is “0” are entropy decoded.

  The above processing is repeated until the last packet of the encoded data.

  As is apparent from the above description, when entropy decoding status management and decoding processing control is performed using a tile attribute, when an entropy decoding abnormality of a packet having a certain tile attribute occurs, the decoding image quality of that tile is determined. However, since the decoded image quality does not deteriorate for other tiles, the overall image quality of the decoded image is improved as compared with the method of stopping the decoding process. In addition, even if entropy decoding is performed on a subsequent packet having the same tile attribute as that of a packet in which an entropy decoding abnormality has occurred, a contribution to the improvement of the decoded image quality is normally hardly expected. Therefore, the entropy of such a packet is not expected. By suppressing the decoding, the processing efficiency is improved, and a special disadvantage to the decoded image quality is avoided.

  When entropy decoding status management and decoding processing control is performed using color component attributes, if an error occurs in entropy decoding of a code having a certain color component attribute, the decoding quality of the color component is degraded, but otherwise As for the color component, the degradation of the decoded image quality does not occur, so that the overall image quality of the decoded image is improved as compared with the method of canceling the decoding process. In addition, even if entropy decoding is performed on a subsequent packet having the same color component attribute as that of the packet in which the entropy decoding abnormality has occurred, it is normal to hardly contribute to the improvement of the decoded image quality. By suppressing the entropy decoding, the processing efficiency is improved and a special disadvantage to the decoded image quality is avoided.

  When entropy decoding status management and decoding processing control are performed using resolution attributes, entropy decoding is suppressed when an entropy decoding error occurs in a packet having a certain resolution attribute. Packet, or a subsequent packet having the resolution attribute and a subsequent packet having a higher resolution attribute. Therefore, the decoding is higher than the method in which the decoding process is stopped at the stage of the packet in which the abnormality occurred. Image quality can be obtained. In addition, since packets whose entropy decoding is suppressed are hardly expected to contribute to the improvement of the decoded image quality even if the entropy decoding is performed, processing is performed by suppressing the entropy decoding of such packets. Efficiency is improved and special disadvantages to decoded image quality are avoided.

  When entropy decoding status management and decoding processing control are performed using image quality attributes, entropy decoding is suppressed when an entropy decoding abnormality having a certain image quality attribute occurs. Or, because it is a subsequent packet with the attribute of the image quality and a subsequent packet with the attribute of the image quality higher than that, the decoding quality is higher than the method of stopping the decoding process at the stage of the packet where the abnormality occurred. Obtainable. In addition, since packets whose entropy decoding is suppressed are hardly expected to contribute to the improvement of the decoded image quality even if the entropy decoding is performed, processing is performed by suppressing the entropy decoding of such packets. Efficiency is improved and special disadvantages to decoded image quality are avoided.

  In addition, for encoded data divided into two or more tiles, when managing entropy decoding status and decoding processing control by color component, resolution, or image quality attribute for each tile, tiles that are not abnormally related In addition to obtaining the highest decoded image quality, it is possible to simultaneously improve the image quality and the processing efficiency as described above for tiles related to abnormalities.

  Returning to FIG. When the processing of the last packet of the encoded data is finished (step S4, YES), the control unit 126 selects one of step S10 or S11 for the image restoration process according to the instruction input from the instruction input device 114 ( Step S9).

  When step S10 is selected, the control unit 126 refers to the error flag list, and the attributes (area, layer, resolution, color component) in the decoded data stored in the data storage unit 127 in which no decoding abnormality has occurred. The image restoration process (inverse quantization, two-dimensional inverse wavelet transform and inverse color space transformation) using only the decoded data of the packet is performed by the inverse quantization unit 123, the two-dimensional inverse wavelet transform unit 124, and the inverse color space transformation unit 125. The generated image data is output to the image display device 111. Therefore, for example, when decoding processing control is performed using a tile attribute, when a decoding error occurs in a packet of a tile, no image data is generated for that tile, and the image is not displayed.

  On the other hand, when step S11 is selected, the image restoration process using all the decoded data stored in the data storage unit 127 (including the decoded data of the packet having the attribute in which decoding abnormality has occurred and the entropy decoded packet) And the generated image data is output to the image display device 111. Therefore, for example, when decoding processing control is performed based on a tile attribute, when a decoding error occurs in a packet of a tile, image data is also generated from the decoded data of the decoded packet and displayed for that tile. .

  In this way, image restoration that does not use the decoded data of the packet having the same attribute as the packet in which the entropy decoding abnormality has occurred, and even if the packet has the same attribute as the packet in which the entropy decoding abnormality has occurred, entropy decoding It is possible to select image restoration using also the decoded data of a packet that has been decoded before the suppression is performed. For example, if an entropy decoding error occurs in a packet of a certain tile, if the former image restoration is selected, the image is not restored for that tile, but if the latter image restoration is selected, the decoded packet of that tile is also restored. It is possible to restore an image with an image quality according to the degree.

  In addition, when processing Motion-JPEG2000 moving image encoded data, the same decoding process is repeated for each frame of the moving image.

  As can be understood from the above description, steps S3, S5, S7, S8, and S9 in FIG. 10 correspond to the function of the control means in the first to seventh aspects of the invention. FIG. 10 also shows the processing procedure of the decoding process in the inventions according to claims 11 to 17, and steps S3, S5, S7, S8, and S9 correspond to the control process.

<Description of operation (2)>
The encoded data of the image designated by the user by the instruction input device 114 is received from the server 102 by the communication device 112, input to the decoding processing device 110 to perform decoding processing, and the decoded image is displayed on the image display device 111. The operation of storing the decoded encoded data in the code storage device 113 will be described. FIG. 15 is a simplified flowchart for the explanation.

  First, the tag processing unit 121 analyzes the main header (and the first tile part header) of the encoded data (step S21). Note that the main header and tile part header are stored in the data storage unit 127. The control unit 126 sets various parameters related to the decoding process based on the header analysis result (step S22). Interpretation of packet attributes and entropy decoding are performed according to the for loop as described above corresponding to the progression order. This for loop is also set at this stage. Although simplified in FIG. 15, the processing in steps S24 to S29 is such a repetitive processing in the for loop. Note that the analysis of the second and subsequent tile part headers is performed at any time in the processing from step S24 onward, and necessary parameter settings are changed according to the analysis results.

  Next, the control unit 126 creates an error flag list based on an instruction from the instruction input device 114 (step S23). The error flag list is as described in FIGS.

  After the above preparation processing, the processing in steps S24 to S29 is performed while reading the code in the encoded data in units of packets.

  First, the control unit 126 classifies the read packets according to their attributes and stores them in the data storage unit 127 (step S25).

  Next, the control unit 126 refers to the error flag list and checks an error state corresponding to the attribute of the read packet (step S26). If the error state is “1”, the control unit 126 controls the entropy decoding unit 122 to read the next packet without performing entropy decoding on the packet.

  On the other hand, if the error state corresponding to the attribute of the packet is “0”, the control unit 122 causes the entropy decoding unit 122 to perform entropy decoding of the packet (step S27). The decoded data (wavelet coefficient) is stored in the data storage unit 127. The control unit 126 checks whether the entropy decoding of the packet has been performed normally (step S28), and performs control to read the next packet if it is normal.

  When an abnormality occurs in the entropy decoding of the packet, the control unit 126 performs necessary correction of the error flag list (step S29), and thereafter performs control to read the next packet. The correction of the error flag list is as described with reference to FIGS.

  The above processing is repeated until the last packet of the encoded data. When the processing of the last packet is finished (step S24, YES), the control unit 126 selects one of step S31 or S32 for the image restoration process according to the instruction input from the instruction input device 114 (step S30). When step S31 is selected, the control unit 126 refers to the error flag list, and the attribute (area, layer, resolution, color component) in the decoded data stored in the data storage unit 127 in which no decoding abnormality has occurred. The image restoration process (inverse quantization, two-dimensional inverse wavelet transform and inverse color space transformation) using only the decoded data of the packet is performed by the inverse quantization unit 123, the two-dimensional inverse wavelet transform unit 124, and the inverse color space transformation unit 125. The generated image data is output to the image display device 111. When step S32 is selected, the image data restoration process using all the decoded data stored in the data storage unit 127 (including the decoded data of the entropy-decoded packet having the attribute in which the decoding abnormality has occurred) is generated and generated. The processed image data is output to the image display device 111.

  Next, the control unit 126 selects one of steps S34 and S35 for code storage in accordance with the instruction input from the instruction input device 114 (step S33).

  When step S34 is selected, the control unit 126 refers to the error flag list, and among the packet groups stored in the data storage unit 127, the attribute (area, layer, resolution, color component) in which the decoding abnormality has occurred. Encoded data in which the code of the attribute in which the decoding error has occurred is deleted by replacing the packet with an empty packet and making necessary corrections to the main header and tile part header stored in the data storage unit 127 Is transferred to the code storage device 113 for storage. The reason why the packet with the attribute in which the decoding abnormality has occurred is not simply deleted but replaced with an empty packet is to format the encoded data into the JPEG2000 format.

  When step S35 is selected, the control unit 126 encodes the encoded data including the main header, tile part header, and all packets stored in the data storage unit 127, that is, the encoded data received from the server 102, as it is. Transfer to the storage device 113 to save.

  In this way, it is possible to store the same encoded data as that captured from an external device, including packets having the same attribute as the packet for which entropy decoding is suppressed, and codes that do not include packets having such an attribute. It is also possible to save data.

  In addition, when processing Motion-JPEG2000 moving image encoded data, the same decoding process is repeated for each frame of the moving image.

  As is apparent from the above description, steps S23, S25, S26, S28, S29, S30, and S33 in FIG. 15 correspond to the function of the control means in the inventions according to claims 1 to 8. FIG. 15 also shows the processing procedure of the decoding process in the inventions according to claims 11 to 18, and steps S23, S25, S26, S28, S29, S30, and S33 correspond to the control process.

  The image processing apparatus 110 described above can be realized in the form of a program in a general-purpose computer such as a personal computer, a portable information terminal having an image display function, a mobile phone, or a built-in microcomputer of various information processing devices. Such an embodiment will be further described by taking a computer having a configuration as shown in FIG. 16 as an example.

  The computer shown in FIG. 16 includes a CPU 200, a memory 202, a display device 204, an auxiliary storage device 206 such as a hard disk, a user input device 208 such as a keyboard and a pointing device, a communication interface 210, and various recording media (magnetic disk, optical disk, magneto-optical). It has a general configuration in which a medium drive device 214 for reading / writing a disk, a semiconductor storage element, or the like is provided and these are interconnected by a system bus 216.

  A program 220 (hereinafter referred to as an image processing program) for causing such a computer to function as each component of the image processing apparatus 110 is read by the medium drive device 214 from the recording medium on which the program is recorded, and is auxiliary stored. It is stored in the device 206 or is taken in from the communication interface 210 via the network and stored in the auxiliary storage device 206. The image processing program 220 is loaded into the memory 202 from the auxiliary storage device 206 and executed by the CPU 200, whereby the image processing device 110 according to the present invention is realized on the computer. The auxiliary storage device 206 is used as the code storage device 113, and the memory 127 is used as the data storage unit 127 in the decoding processing device 110. Note that in an apparatus such as a portable information terminal, the image processing program 220 may be implemented in the form of a ROM, and such an aspect is also included in this embodiment. The image processing program 220 and various recording media (including semiconductor memory elements such as the ROM) on which the image processing program 220 is recorded are also included in the present embodiment.

  For example, encoded data of a still image or a moving image to be processed is acquired from the server 102 on the network through the communication interface 210 or is acquired from the auxiliary storage device 206 or the medium drive device 214 and processed.

  According to one typical aspect, the image processing program 220 operates in cooperation with another program 222 (hereinafter referred to as a viewer / browser) for viewing still images or moving images called a viewer, a browser, or the like. Take shape. However, the viewer / browser 222 and the image processing program 220 can be integrated. Such an integrated program, a recording medium on which the program is recorded, and an image processing system realized on a computer by the program are also included in the present embodiment.

  The image processing program 220 executes decoding processing of encoded data of a still image or a moving image to reproduce the image data, and the viewer / browser 222 causes the image display window 230 to display this image data. As described above, the decoding processing of the encoded data is performed by the image processing program 220, but the processing and control for displaying the decoded image data on the screen of the display device 204 is performed by the viewer / browser 230. That is, the image display device 111 is realized by the viewer / browser 222 and the display device 204.

  The viewer / browser 222 opens an image display window 230 on the screen of the display device 204, for example, as schematically shown in FIG. 17, and displays a moving image or a still image there. Displays buttons and slide bars for various specifications. Usually, in addition to designation of an image to be displayed (designation of a file name and URL), the vertical and horizontal sizes of the image display window 230 and the image display magnification are changed by operating a pointing device such as a mouse included in the user input device 208. It is possible to scroll an image larger than the image display window 230, specify a specific area (position), and the like. In addition, various conditions relating to a moving image or a still image can be designated by a button or a slide bar displayed in the control area 232, and the designated content is notified to the image processing program 220. An instruction as to what kind of attributes (area, image quality, resolution, color component) to perform entropy decoding state management and decoding processing control as described above, and instructions related to steps S9, S30, and S33 are also included in the control area 232. This is done using the buttons displayed on the screen. That is, the instruction input device 114 is realized by the viewer / browser 222 and the user input device 208.

  Up to this point, the case where JPEG2000 still image encoded data or Motion-JPEG2000 moving image encoded data is processed has been described. However, the present invention is also applied to an image processing apparatus that processes encoded data using other encoding methods. It is clear that the same applies.

It is a block diagram for demonstrating the algorithm of JPEG2000. It is explanatory drawing of tile division | segmentation. It is explanatory drawing of a two-dimensional wavelet transform. It is a figure which shows the format of the encoding data of JPEG2000. It is a figure which shows the relationship between a tile, a subband, a precinct, and a code block. It is a figure which shows the example of a layer division | segmentation. It is a figure which shows the packet array example of LRCP progression. It is a figure which shows the example of a packet arrangement | sequence of RLCP progression. It is a block diagram for demonstrating embodiment of this invention. 6 is a flowchart for explaining the operation of the image processing apparatus according to the present invention. It is explanatory drawing of the error flag list | wrist for entropy decoding state management by a tile attribute. It is explanatory drawing of the error flag list | wrist for entropy decoding state management by a layer attribute. It is explanatory drawing of the error flag list | wrist for entropy decoding state management by a resolution attribute. It is explanatory drawing of the error flag list | wrist for entropy decoding state management by a component attribute. 6 is a flowchart for explaining the operation of the image processing apparatus according to the present invention. It is a block diagram for demonstrating embodiment using a computer. It is explanatory drawing of the screen display by a viewer / browser.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Image processing apparatus 101 Communication path 102 Server 110 Decoding processing apparatus 112 Communication apparatus 113 Code storage apparatus 121 Tag processing part 122 Entropy decoding part 123 Inverse quantization part 124 Two-dimensional inverse wavelet transformation part 125 Inverse color space transformation part 126 Control part 127 Data storage unit

Claims (18)

An image processing device including a decoding processing device that performs decoding processing of encoded data of an image, which includes a code having an area attribute,
The state of entropy decoding of codes in the encoded data in the decoding processing device is managed for each area, and when an abnormality occurs in entropy decoding of a code having an attribute of a certain area, a subsequent attribute having the attribute of the certain area An image processing apparatus comprising control means for performing control for suppressing entropy decoding of a code. An image processing apparatus including a decoding processing apparatus that performs decoding processing of encoded data of an image, which includes codes having color component attributes,
The state of entropy decoding of the code in the encoded data in the decoding processing device is managed for each color component, and when an abnormality occurs in the entropy decoding of the code having the attribute of a certain color component, the attribute of the certain color component is An image processing apparatus comprising control means for performing control to suppress entropy decoding of a subsequent code. An image processing apparatus including a decoding processing apparatus that performs decoding processing of encoded data of an image, which includes a code having a resolution attribute,
The state of entropy decoding of the code in the encoded data in the decoding processing device is managed for each resolution, and when an abnormality occurs in the entropy decoding of the code having a certain resolution attribute, An image processing apparatus comprising control means for performing control for suppressing entropy decoding of a code. An image processing apparatus including a decoding processing apparatus that performs decoding processing of encoded data of an image, which includes a code having a resolution attribute,
The state of entropy decoding of the code in the encoded data in the decoding processing device is managed for each resolution, and when an abnormality occurs in the entropy decoding of the code having a certain resolution attribute, An image processing apparatus comprising: a control unit that performs control to suppress entropy decoding of a code and a subsequent code having a higher resolution attribute than the certain resolution. An image processing device including a decoding processing device that performs decoding processing of encoded data of an image, which includes a code having an image quality attribute,
The state of entropy decoding of codes in the encoded data in the decoding processing device is managed for each image quality, and when an abnormality occurs in entropy decoding of a code having a certain image quality attribute, An image processing apparatus comprising control means for performing control for suppressing entropy decoding of a code. An image processing device including a decoding processing device that performs decoding processing of encoded data of an image, which includes a code having an image quality attribute,
The state of entropy decoding of codes in the encoded data in the decoding processing device is managed for each image quality, and when an abnormality occurs in entropy decoding of a code having a certain image quality attribute, An image processing apparatus comprising: a control unit that performs control to suppress entropy decoding of a code and a subsequent code having an image quality attribute higher than the certain image quality.   The control means controls whether or not to use decoded data having a code having the same attribute as that of a code for which entropy decoding is suppressed in the image restoration processing in the decoding processing device. The image processing apparatus according to any one of claims 6 to 7. The image processing apparatus according to any one of claims 1 to 6, wherein encoded data of an image is fetched from an external apparatus, and is decoded by the decoding processing apparatus.
A code storage device for storing the encoded data decoded by the decoding processing device;
The control means controls whether or not to include in the encoded data stored in the code storage device a code having the same attribute as the code whose entropy decoding is suppressed in the decoding processing device. Processing equipment.   A program that causes a computer to function as the decoding processing device and control means according to claim 1.   9. A computer-readable information recording medium in which a program for causing a computer to function as the decoding processing apparatus and control means according to claim 1 is recorded. A decoding process step of performing decoding processing of encoded data of an image consisting of codes having region attributes;
The decoding process step manages the entropy decoding state of the code in the encoded data for each area, and when an abnormality occurs in the entropy decoding of the code having the attribute of a certain area, the subsequent process having the attribute of the certain area The image processing method characterized by including the control process which performs control which suppresses entropy decoding of the code | symbol of this. A decoding process step of performing decoding processing of encoded data of an image including a code having an attribute of a color component;
The decoding process step manages the entropy decoding state of the code in the encoded data for each color component, and when an abnormality occurs in the entropy decoding of the code having the attribute of a certain color component, the attribute of the certain color component An image processing method comprising a control step of performing control to suppress entropy decoding of a subsequent code having A decoding process step for decoding encoded data of an image, which includes a code having a resolution attribute;
The decoding process step manages the entropy decoding state of the code in the encoded data for each resolution, and when an abnormality occurs in the entropy decoding of the code having a certain resolution attribute, the subsequent process having the certain resolution attribute The image processing method characterized by including the control process which performs control which suppresses entropy decoding of the code | symbol of this. A decoding process step for decoding encoded data of an image, which includes a code having a resolution attribute;
The decoding process step manages the entropy decoding state of the code in the encoded data for each resolution, and when an abnormality occurs in the entropy decoding of the code having a certain resolution attribute, the subsequent process having the certain resolution attribute And a control step of controlling to suppress entropy decoding of a subsequent code having a higher resolution attribute than the certain resolution. A decoding process step for decoding encoded data of an image, which includes a code having an image quality attribute;
The decoding process step manages the entropy decoding state of the code in the encoded data for each image quality, and when an abnormality occurs in the entropy decoding of the code having a certain image quality attribute, the subsequent process having the certain image quality attribute The image processing method characterized by including the control process which performs control which suppresses entropy decoding of the code | symbol of this. A decoding process step for decoding encoded data of an image, which includes a code having an image quality attribute;
The decoding process step manages the entropy decoding state of the code in the encoded data for each image quality, and when an abnormality occurs in the entropy decoding of the code having a certain image quality attribute, the subsequent process having the certain image quality attribute And a control step for controlling to suppress entropy decoding of a subsequent code having an image quality attribute higher than the certain image quality.   12. The control process according to claim 11, wherein the control process controls whether or not to use decoded data having a code having the same attribute as that of the code for which entropy decoding is suppressed in the image restoration process in the decoding process. The image processing method according to claim 16. An encoded data storage step for storing the encoded data decoded by the decoding processing step;
The control step controls whether or not the encoded data stored in the encoded data storage step includes a code having the same attribute as the code for which entropy decoding is suppressed in the decoding processing step. The image processing method according to claim 11.

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