CA2325065A1 - Picture coding and decoding apparatus with less transmission amount - Google Patents
Picture coding and decoding apparatus with less transmission amount Download PDFInfo
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Abstract
A picture coding and decoding apparatus includes a coding section, a demultiplexing section, a coding control section, an error detecting section and a notifying section. The coding section codes a picture data. The demultiplexing section demultiplexes a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated.
The coding control section controls the coding section based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section. The error detecting section detects an error from the demultiplexed coded data. The notifying section notifies another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
The coding control section controls the coding section based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section. The error detecting section detects an error from the demultiplexed coded data. The notifying section notifies another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
Description
PICTURE CODING AND DECODING APPARATUS
WITH LESS TRANSMISSION AMOUNT
Background of the Invention 1. Field of the Invention The present invention relates to a picture coding and decoding apparatus. More particularly, the present invention relates to a picture coding and decoding apparatus which can code picture data for terminals such as a picture phone and a video conferencing terminal and prevent influence to decoded picture data due to a decoding error.
WITH LESS TRANSMISSION AMOUNT
Background of the Invention 1. Field of the Invention The present invention relates to a picture coding and decoding apparatus. More particularly, the present invention relates to a picture coding and decoding apparatus which can code picture data for terminals such as a picture phone and a video conferencing terminal and prevent influence to decoded picture data due to a decoding error.
2. Description of the Related Art Picture data is compressed, coded and transmitted to increase communication efficiency. As a method of efficiently coding and compressing picture data, a method in which motion compensation, a 2-dimensional discrete cosine transform and a Huffman coding method are combined is known such as ITU
(International Telecommunication Union) recommendation H.261 and H.263, and ISO (International Organization for Standardization) recommendation MPEG-1, MPEG-2, and MPEG-4. The picture data coded by such a method has a 3-layer structure of a picture, a slice and a macroblock. The picture is a unit of codec image. The macroblock is a block when the picture data is divided to have the size of 16 pixels by 16 pixels generally.
The slice is a group of the macroblocks in which the coding order is continuous and is also called GOB
(group of blocks) and a video packet. The picture coding process is carried out in units of macroblocks.
The coding of the macroblock is roughly divided into two systems: intra mode and inter mode.
In the intra mode, a coding operation is carried out using only the data in the macroblock, and in case of a decoding operation, picture data is reconstructed using only the data in the macroblock. In the inter mode, the coding operation is carried out using difference between reference picture data and motion-compensated picture data. In case of the decoding operation, the reference picture and the coding data are necessary to reconstruct macroblock. The picture data before or after the picture data to be coded is selected as the reference picture data. The coding operation using the macroblock is carried out in order from the left to the right and from the top to the bottom using an upper left block as a start point.
The slice is suitably set in accordance with picture coding algorithm. The macroblock at the head of the slice is coded in the intra mode, and the subsequent macroblocks are coded in either of the intra mode and the inter mode.
The decoded picture data degrades because of the accumulation of coding errors when a macroblock in a specific position is always coded in the inter mode.
Therefore, a coding apparatus is controlled in such a manner that the coding operation in the intra mode is carried out in a suitable interval. This control is called an intra-refresh operation. Generally, difference between the macroblock previously coded and a current macroblock is manipulated as current macroblock data in the slice. A start code and header data are added to the heads of the picture data of slice to indicate the start points. The start code and header data are used as the synchronization points when s picture decoding apparatus decodes coded picture data.
In the picture data coding and decoding apparatus using such a picture coding method, when a coding error occurs during the coding operation of received picture data, a normal decoding operation cannot be carried out. Therefore, the erroneous decoding operation is continued to the next synchronization point, or the erroneous decoding operation is stopped once and skipped to the next synchronization point. As a result, the decoded picture data is degraded from the coding error occurring position to the synchronization point in the reconstructed picture data. Moreover, the degraded macroblock is used as a reference macroblock until an intra-refresh operation is next carried out.
(International Telecommunication Union) recommendation H.261 and H.263, and ISO (International Organization for Standardization) recommendation MPEG-1, MPEG-2, and MPEG-4. The picture data coded by such a method has a 3-layer structure of a picture, a slice and a macroblock. The picture is a unit of codec image. The macroblock is a block when the picture data is divided to have the size of 16 pixels by 16 pixels generally.
The slice is a group of the macroblocks in which the coding order is continuous and is also called GOB
(group of blocks) and a video packet. The picture coding process is carried out in units of macroblocks.
The coding of the macroblock is roughly divided into two systems: intra mode and inter mode.
In the intra mode, a coding operation is carried out using only the data in the macroblock, and in case of a decoding operation, picture data is reconstructed using only the data in the macroblock. In the inter mode, the coding operation is carried out using difference between reference picture data and motion-compensated picture data. In case of the decoding operation, the reference picture and the coding data are necessary to reconstruct macroblock. The picture data before or after the picture data to be coded is selected as the reference picture data. The coding operation using the macroblock is carried out in order from the left to the right and from the top to the bottom using an upper left block as a start point.
The slice is suitably set in accordance with picture coding algorithm. The macroblock at the head of the slice is coded in the intra mode, and the subsequent macroblocks are coded in either of the intra mode and the inter mode.
The decoded picture data degrades because of the accumulation of coding errors when a macroblock in a specific position is always coded in the inter mode.
Therefore, a coding apparatus is controlled in such a manner that the coding operation in the intra mode is carried out in a suitable interval. This control is called an intra-refresh operation. Generally, difference between the macroblock previously coded and a current macroblock is manipulated as current macroblock data in the slice. A start code and header data are added to the heads of the picture data of slice to indicate the start points. The start code and header data are used as the synchronization points when s picture decoding apparatus decodes coded picture data.
In the picture data coding and decoding apparatus using such a picture coding method, when a coding error occurs during the coding operation of received picture data, a normal decoding operation cannot be carried out. Therefore, the erroneous decoding operation is continued to the next synchronization point, or the erroneous decoding operation is stopped once and skipped to the next synchronization point. As a result, the decoded picture data is degraded from the coding error occurring position to the synchronization point in the reconstructed picture data. Moreover, the degraded macroblock is used as a reference macroblock until an intra-refresh operation is next carried out.
Therefore, the reconstructed picture data is also degraded. Thus, it is required that even if the decoding error occurs, the picture data is recovered quickly so that the picture data with good quality can be reconstructed.
To respond to such requirement, a proposal is made in Japanese Laid Open Patent Application (JP-A-Heisei 7-312755). In this reference, when a decoding error has occurred, an interpolation picture is produced and an erroneous macroblock is replaced by the interpolation picture. Also, the decoding error is notified to the coding apparatus. The coding apparatus carries out the coding operation in the intra mode to the corresponding macroblock and the subsequent macroblocks in response to the notice. In the technique disclosed in this reference technique, there are provided a coding error detecting section (103) of the received data, an interpolation picture generating section (104) for generating the interpolation picture for the macroblock in which the decoding error has occurred, a coding error notifying section (105) for notifying to the coding apparatus decoding error information indicating that the decoding error has occurred, and a coding control section (106) for controlling a coding section using the decoding error information, in addition to a coding main body (101) and a decoding main body (102), as shown in Fig. 1.
In the above reference, the existence or non-existence of the coding error about all the decoded macroblocks, and a GOB number and a macroblock address when there is any error are transmitted to the coding apparatus. Therefore, the error information becomes relatively large in size in case of a low bit rate communication of 64 kbps. As a result, the amount of allocatable coded picture data decreases, so that the picture quality of the picture to be transmitted degrades. Moreover, when the macroblock in which the coding error has occurred in a moving region, the coding apparatus is controlled to code all the macroblocks contained in the moving region in the intra mode. Therefore, the coding operation in the intra mode is carried out to the macroblock which does not undergo influence of the coding error. As a result, the coding efficiency is decreased and the picture quality of the picture to be transmitted is degraded.
In conjunction with the above description, an image transmitting system is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 10-79949).
In this reference, existence or non-existence of a decoding error of coded data is transmitted from an image decoding apparatus to an image coding apparatus.
In this case, the existence or non-existence situations of the decoding errors in blocks or frames are collectively transmitted. By this, the image coding apparatus can carry out a coding operation by use of the frame which could be decoded on the side of the image decoding apparatus as a reference frame.
The existence or non-existence situations of the decoding errors in a plurality of blocks or frames are collectively transmitted, not to require a wide band for the above transmission.
Also, an image 'transmission system is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 10-93979). In this reference, an image signal receiving section (608) on an image receiving side detects existence or non-existence of an error in a received image data. The detection result is notified to a signal receiving section (602) on an image transmitting side via a signal transmitting section (609). The signal receiving section (602) notifies the received existence or non-existence of the error to a frame memory changing section (605).
The frame memory changing section (605) controls a write operation based on the notice from the signal receiving section (602) such that at least a reference image from a coding section (601) when the image data is correctly received is remained in a frame memory section (603). A reference image determining section (604) selects one of the reference images stored in _ 7 _ the frame memory section (603) to send to the coding section (601). The number of the reference image selected at that time is notified to the image receiving side via a reference image notifying section (606) for a decoding operation.
Also, an image coding apparatus is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 10-145794). In this reference, one frame of picture data is divided into regions with a size, coded and transmitted from a transmitting side. When an error has occurred during a decoding operation of coded picture data at the receiving side, the occurrence of the error is notified to the transmitting side. A
refreshed picture data which is not influenced by the decoding error is coded and transmitted. Also, when the error notice is received from the receiving side, a region where has a large change is estimated at the transmitting side and the estimated region is refreshed, coded and transmitted.
Also, a picture transmitting apparatus is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 10-200897). In this reference, a coding control section (2b) is provided to randomly determine whether the next frame should be coded in an intra mode or fixed-mode (previous frame is repeated), in a predetermined probability in response to a notice indicative of a transmission error from a receiving _ g _ side. Thus, the inter mode coding operation is not always carried out in response to the transmission error.
Also, an image transmitting apparatus is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 11-69355). In this reference, a reception image code data S51 is received from a transmission path and separated by a multiplexing/demultiplexing section (110), and supplied to a buffer (503) and an error detecting variable length decoder (504). When an error is detected during the decoding operation so that the decoding operation is impossible, the decoder (504) notifies an error notice to a decoding control section (505). Thus, the decoding control section (505) outputs a refresh request signal to the multiplexing/demultiplexing section (110), which transmits it to a transmitting side.
In addition, a picture coding and decoding apparatus is disclosed in W095/33341. In this reference, the picture coding and decoding apparatus is composed of a region shape detecting section (12) for distinguishing a motion compensation region and the other region in one frame, and detecting the shape of the motion compensation region, and a motion direction estimating section (14) for estimating a motion direction from an estimated motion start point.
_ g _ A refresh operation is carried out from the estimated motion start point to the estimated motion direction in the motion compensation region. Also, when a code error has occurred, a coding error block number notifying section (13) notifies the number of a block in which the code error has occurred. A refresh operation start point is in a block neighbor to the block of the notified number and neighbor block is positioned in a direction opposite to the estimated motion direction. Thus, the refresh operation is efficiently carried out to recover the picture degradation due to the code error in a short time.
Summary of the Invention Therefore, an object of the present invention is to provide a picture coding and/or decoding apparatus in which the decrease of coding efficiency can be prevented.
Another object of the present invention is to provide a picture coding and decoding apparatus in which the picture quality of the picture to be transmitted can be prevented.
Still another object of the present invention is to provide a picture coding and decoding apparatus in which the decrease of coding efficiency can be prevented even if a macroblock is in a moving region.
In order to achieve an aspect of the present invention, a picture coding and decoding apparatus includes a coding section, a demultiplexing section, a coding control section, an error detecting section and a notifying section. The coding section codes a picture data. The demultiplexing section demultiplexes a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated.
The coding control section controls the coding section based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section. The error detecting section detects an error from the demultiplexed coded data. The notifying section notifies another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
The error detecting section may detect the error from the demultiplexed coded data for every macroblock, and the notifying section may notify the another error detected macroblock number to the another apparatus based on the detection of the coding error, determine whether the error continues, and notify the another recovered macroblock number to the another apparatus when the error is eliminated.
Also, the coding control section may control the coding section to code the picture data from the macroblock corresponding to the error detected macroblock number to the macroblock corresponding to the recovered macroblock number in an intra mode.
In order to another aspect of the present invention, a picture coding apparatus includes a coding section which codes picture data, a demultiplexing section which demultiplexes coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated, and a coding control section which controls the coding section based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section. In this case, the coding control section may control the coding section to code the picture data from the macroblock corresponding to the error detected macroblock number to the macroblock corresponding to the recovered macroblock number in an intra mode.
In order to still another aspect of the present invention, a picture decoding apparatus includes an error detecting section which detects an error from coded data, and a notifying section which notifies an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error. In this case, the error detecting section detects the error from the demultiplexed coded data for every macroblock, and the notifying section notifies the error detected macroblock number to the another apparatus based on the detection of the coding error, determines whether the error continues, and notifies the recovered macroblock number to the another apparatus when the error is eliminated.
In an aspect of the present invention, a method of coding and decoding picture data is attained by demultiplexing a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
by controlling a coding operation based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section; by detecting an error from the demultiplexed coded data;
and by notifying another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
In this case, the detection may include:
detecting the error from the demultiplexed coded data for every macroblock, and the notifying may include:
notifying the another error detected macroblock number to the another apparatus based on the detection of the coding error; determining whether the error continues;
and notifying the another recovered macroblock number to the another apparatus when the error is eliminated.
Also, the controlling may include: controlling the coding operation to the picture data from the macroblock corresponding to the error detected macroblock number to the macroblock corresponding to the recovered macroblock number in an intra mode.
In another aspect of the present invention, a method of coding picture data is attained by carrying out a coding operation of picture data; by demultiplexing coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
and by controlling the coding operation based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section. In this case, the controlling may include: controlling the coding operation to the picture data from the macroblock corresponding to the error detected macroblock number to the macroblock corresponding to the recovered macroblock number in an intra mode.
In still another aspect of the present invention, a method of decoding picture data is attained by detecting an error from coded data; and by notifying an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error. In this case, the detecting may include: detecting the error from the demultiplexed coded data for every macroblock, and the notifying may include: notifying the error detected macroblock number to the another apparatus based on the detection of the coding error; determining whether the error continues; and notifying the recovered macroblock number to the another apparatus when the error is eliminated.
In an aspect of the present invention, there is provided a recording medium in which a program is recorded for either of the above-mentioned methods.
Brief Description of the Drawings Fig. 1 is a circuit block diagram showing a conventional coding and decoding system;
Fig. 2 is a circuit block diagram showing the structure of a picture coding and decoding apparatus according to an embodiment of the present invention;
Fig. 3 is a flow chart for describing a picture coding and decoding method in the embodiment of the present invention;
Fig. 4 is a diagram showing a picture block;
and Fig. 5 is a circuit block diagram showing the system configuration in the embodiment of the present invention.
Description of the Preferred Embodiments Hereinafter, a picture coding and decoding apparatus of the present invention will be described below in detail with reference to the attached drawings.
Fig. 2 is a block diagram showing the structure of the picture coding and decoding apparatus according to an embodiment of the present invention.
Referring to Fig. 2, the picture coding and decoding apparatus is composed of a picture coding section 1 and a picture decoding section 9. Input picture data 2 is supplied to the picture coding section 1. The picture coding section 1 carries out the coding operation of the input picture data 2 and outputs coded picture data 3.
The picture coding section 1 is connected with a multiplexing section 4. The multiplexing section 4 sends out to a transmission path, coded data 5 in which the coded picture data 3, coded sound data, and the other coded data are multiplexed. A
demultiplexing section 6 separates received coded data 7 in coded sound data, coded picture data 8, and the other coded data. The demultiplexing section 6 is connected with the picture decoding section 9. The picture decoding section 9 carries out a decoding operation of the coded picture data 8 and outputs a reconstructed picture 11.
Also, the picture coding and decoding apparatus is further composed of a macroblock number notifying section 12, a coding operation control section 13 and a coding information storage section 14.
The picture decoding section 9 outputs existence or non-existence 15 of a decoding error macroblock and a macroblock number 16 of the decoding error macroblock 15. The macroblock number notifying section 12 receives the existence or non-existence 15 of the decoding error macroblock and the macroblock number 16, and sends to the multiplexing section 4, the macroblock number 16E as an error start macroblock when the decoding error is detected and a macroblock number 16R as an error end macroblock when the decoding operation is revered to a normal state. The macroblock number 16 is multiplexed with the other coded data and is transmitted to another picture coding and decoding apparatus (not shown).
The demultiplexing section 6 is connected with the coding control section 13. The coding control section 13 receives the macroblock number 16E
of the error start macroblock and the macroblock number 16R of the error end macroblock through the demultiplexing section 6. The macroblock number 16E
of the error start macroblock and the macroblock number 16R of the error end macroblock are stored in the coding information storage section 14. The coding control section 13 refers to coding information such as intra-macroblock and a slice structure necessary to control the picture coding section 1. Also, the coding control section 13 store the coding information in the coding information storage section 14.
The picture decoding section 9 determines whether or not a decoding error has occurred during the decoding operation for every macroblock. The picture decoding section 9 notifies the determination result and the macroblock number 16 to the decoding error macroblock number notifying section 12. The determination of existence or non-existence 15 of the decoding error macroblock can be carried out based on the appearance of a symbol, which is not in a coding table, and the appearance of information which is hardly possible to appear. The macroblock number 16E
or 16R is allocated to allow the position of the macroblock to be recognized uniquely based on the number. For example, the macroblock numbers are allocated in a manner from the upper left of the picture data as a start point to the right and from the top to the bottom such as 1, 2, 3. The coding section and the decoding section share the same data.
Fig. 3 shows the operation of the decoding error macroblock number notifying section 12. When the picture decoding process is started, the macroblock number notifying section 12 receives an error determination result of a macroblock from the picture decoding section 9 (Step S1). Then, the macroblock number notifying section 12 determines the existence or non-existence of the decoding error.
When there is any decoding error, the macroblock number notifying section 12 sends out to the multiplexing section 4, the number 16E of the macroblock in which the coding error has first occurred (Step S2). Then, the macroblock number notifying section 12 continues the reception of the determination result carried out for every macroblock by the decoding section 9 (Step S3). While sending out the number 16E of the macroblock in which the decoding error is found to the multiplexing section 4, the macroblock number notifying section 12 waits for the number of a macroblock which has returned to the normal state with no decoding error. When receiving the normal macroblock, the macroblock number notifying section 12 sends out the number 16R of the error end macroblock (Step S4). Generally, the error end macroblock emerges at the synchronization point of the picture or the slice. However, when an error is mixed in the data at the synchronization point, the error macroblocks sometime emerges over a plurality of slices.
Fig. 4 shows the structure of the slices. The coding control section 13 stores the coding condition of the picture data in the coding information storage section 14. The coding condition contains information of the structure of the slice 21 and intra-refresh.
When there is no a decoding error, the coding control section 13 determines the structure of the slice 21 in the suitable way and carries out the intra-refresh operation.
When the error start macroblock number 16E
and the error end macroblock number 16R are received, the numbers of macroblocks between the macroblocks corresponding to the numbers 16E and 16R is stored.
Then, the picture coding section 1 is controlled to carry out the intra-refresh operation to the macroblocks for the stored numbers. A motion compensator (not shown) is controlled not to use the picture data contained in the error macroblocks in case of motion compensation of the macroblocks in the inter mode.
Fig. 4 shows the structure of a slice 21 of a coded picture data surrounded by a thick line. The mark indicates the macroblock 22 in which the decoding error has occurred and the ~ mark indicates the macroblock 23 which has returned to the normal state.
The coding control section 13 attaches a mark to the macroblocks between the error start macroblock to the error end macroblock. In Fig. 4, the D mark indicates the error macroblock.
When coding the next picture data, the picture coding section 1 is controlled to code the error macroblocks in the intra mode. The macroblocks to be coded in the inter mode other than the error macroblocks are controlled not to be used for the motion compensation of the picture data containing the error macroblocks.
Fig. 5 shows another embodiment in which the picture coding and decoding apparatus is realized by a program for a microprocessor. The program for picture coding and decoding operations is recorded on a recording medium 31. The recording medium 31 can be such as a magnetic disk and a semiconductor memory recording medium. The picture coding and decoding program is read by a microprocessor 32 from the recording medium 31 and used to control the operation of the microprocessor 32. The microprocessor 32 executes the above-mentioned steps shown in Fig. 3.
The data necessary for the decoding operation such as sequence information and a macroblock count are stored in a memory 33.
In the circuit block shown in Fig. 2, only a transmitting side or a receiving side is shown. The interactive communication becomes possible by use of the circuit block in the transmitting side and the receiving side. Thus, the TV conference system can be structured.
In the picture coding and decoding apparatus of the present invention, the numbers of the error start macroblock and error end macroblock are notified to a counter end. Therefore, influence such as the decrease of an allocatable code quantity to the normally coded picture data can be prevented.
Also, the error macroblocks in which an error has occurred are intra-refreshed so that the degraded picture returns quickly to a normal state. Moreover, the macroblocks in which the error did not occur are coded in the inter mode, although there is a limitation to motion compensation. Therefore, the increase of the code quantity can be suppressed, compared with the case where all the macroblocks are coded in the intra mode.
To respond to such requirement, a proposal is made in Japanese Laid Open Patent Application (JP-A-Heisei 7-312755). In this reference, when a decoding error has occurred, an interpolation picture is produced and an erroneous macroblock is replaced by the interpolation picture. Also, the decoding error is notified to the coding apparatus. The coding apparatus carries out the coding operation in the intra mode to the corresponding macroblock and the subsequent macroblocks in response to the notice. In the technique disclosed in this reference technique, there are provided a coding error detecting section (103) of the received data, an interpolation picture generating section (104) for generating the interpolation picture for the macroblock in which the decoding error has occurred, a coding error notifying section (105) for notifying to the coding apparatus decoding error information indicating that the decoding error has occurred, and a coding control section (106) for controlling a coding section using the decoding error information, in addition to a coding main body (101) and a decoding main body (102), as shown in Fig. 1.
In the above reference, the existence or non-existence of the coding error about all the decoded macroblocks, and a GOB number and a macroblock address when there is any error are transmitted to the coding apparatus. Therefore, the error information becomes relatively large in size in case of a low bit rate communication of 64 kbps. As a result, the amount of allocatable coded picture data decreases, so that the picture quality of the picture to be transmitted degrades. Moreover, when the macroblock in which the coding error has occurred in a moving region, the coding apparatus is controlled to code all the macroblocks contained in the moving region in the intra mode. Therefore, the coding operation in the intra mode is carried out to the macroblock which does not undergo influence of the coding error. As a result, the coding efficiency is decreased and the picture quality of the picture to be transmitted is degraded.
In conjunction with the above description, an image transmitting system is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 10-79949).
In this reference, existence or non-existence of a decoding error of coded data is transmitted from an image decoding apparatus to an image coding apparatus.
In this case, the existence or non-existence situations of the decoding errors in blocks or frames are collectively transmitted. By this, the image coding apparatus can carry out a coding operation by use of the frame which could be decoded on the side of the image decoding apparatus as a reference frame.
The existence or non-existence situations of the decoding errors in a plurality of blocks or frames are collectively transmitted, not to require a wide band for the above transmission.
Also, an image 'transmission system is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 10-93979). In this reference, an image signal receiving section (608) on an image receiving side detects existence or non-existence of an error in a received image data. The detection result is notified to a signal receiving section (602) on an image transmitting side via a signal transmitting section (609). The signal receiving section (602) notifies the received existence or non-existence of the error to a frame memory changing section (605).
The frame memory changing section (605) controls a write operation based on the notice from the signal receiving section (602) such that at least a reference image from a coding section (601) when the image data is correctly received is remained in a frame memory section (603). A reference image determining section (604) selects one of the reference images stored in _ 7 _ the frame memory section (603) to send to the coding section (601). The number of the reference image selected at that time is notified to the image receiving side via a reference image notifying section (606) for a decoding operation.
Also, an image coding apparatus is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 10-145794). In this reference, one frame of picture data is divided into regions with a size, coded and transmitted from a transmitting side. When an error has occurred during a decoding operation of coded picture data at the receiving side, the occurrence of the error is notified to the transmitting side. A
refreshed picture data which is not influenced by the decoding error is coded and transmitted. Also, when the error notice is received from the receiving side, a region where has a large change is estimated at the transmitting side and the estimated region is refreshed, coded and transmitted.
Also, a picture transmitting apparatus is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 10-200897). In this reference, a coding control section (2b) is provided to randomly determine whether the next frame should be coded in an intra mode or fixed-mode (previous frame is repeated), in a predetermined probability in response to a notice indicative of a transmission error from a receiving _ g _ side. Thus, the inter mode coding operation is not always carried out in response to the transmission error.
Also, an image transmitting apparatus is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 11-69355). In this reference, a reception image code data S51 is received from a transmission path and separated by a multiplexing/demultiplexing section (110), and supplied to a buffer (503) and an error detecting variable length decoder (504). When an error is detected during the decoding operation so that the decoding operation is impossible, the decoder (504) notifies an error notice to a decoding control section (505). Thus, the decoding control section (505) outputs a refresh request signal to the multiplexing/demultiplexing section (110), which transmits it to a transmitting side.
In addition, a picture coding and decoding apparatus is disclosed in W095/33341. In this reference, the picture coding and decoding apparatus is composed of a region shape detecting section (12) for distinguishing a motion compensation region and the other region in one frame, and detecting the shape of the motion compensation region, and a motion direction estimating section (14) for estimating a motion direction from an estimated motion start point.
_ g _ A refresh operation is carried out from the estimated motion start point to the estimated motion direction in the motion compensation region. Also, when a code error has occurred, a coding error block number notifying section (13) notifies the number of a block in which the code error has occurred. A refresh operation start point is in a block neighbor to the block of the notified number and neighbor block is positioned in a direction opposite to the estimated motion direction. Thus, the refresh operation is efficiently carried out to recover the picture degradation due to the code error in a short time.
Summary of the Invention Therefore, an object of the present invention is to provide a picture coding and/or decoding apparatus in which the decrease of coding efficiency can be prevented.
Another object of the present invention is to provide a picture coding and decoding apparatus in which the picture quality of the picture to be transmitted can be prevented.
Still another object of the present invention is to provide a picture coding and decoding apparatus in which the decrease of coding efficiency can be prevented even if a macroblock is in a moving region.
In order to achieve an aspect of the present invention, a picture coding and decoding apparatus includes a coding section, a demultiplexing section, a coding control section, an error detecting section and a notifying section. The coding section codes a picture data. The demultiplexing section demultiplexes a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated.
The coding control section controls the coding section based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section. The error detecting section detects an error from the demultiplexed coded data. The notifying section notifies another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
The error detecting section may detect the error from the demultiplexed coded data for every macroblock, and the notifying section may notify the another error detected macroblock number to the another apparatus based on the detection of the coding error, determine whether the error continues, and notify the another recovered macroblock number to the another apparatus when the error is eliminated.
Also, the coding control section may control the coding section to code the picture data from the macroblock corresponding to the error detected macroblock number to the macroblock corresponding to the recovered macroblock number in an intra mode.
In order to another aspect of the present invention, a picture coding apparatus includes a coding section which codes picture data, a demultiplexing section which demultiplexes coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated, and a coding control section which controls the coding section based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section. In this case, the coding control section may control the coding section to code the picture data from the macroblock corresponding to the error detected macroblock number to the macroblock corresponding to the recovered macroblock number in an intra mode.
In order to still another aspect of the present invention, a picture decoding apparatus includes an error detecting section which detects an error from coded data, and a notifying section which notifies an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error. In this case, the error detecting section detects the error from the demultiplexed coded data for every macroblock, and the notifying section notifies the error detected macroblock number to the another apparatus based on the detection of the coding error, determines whether the error continues, and notifies the recovered macroblock number to the another apparatus when the error is eliminated.
In an aspect of the present invention, a method of coding and decoding picture data is attained by demultiplexing a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
by controlling a coding operation based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section; by detecting an error from the demultiplexed coded data;
and by notifying another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
In this case, the detection may include:
detecting the error from the demultiplexed coded data for every macroblock, and the notifying may include:
notifying the another error detected macroblock number to the another apparatus based on the detection of the coding error; determining whether the error continues;
and notifying the another recovered macroblock number to the another apparatus when the error is eliminated.
Also, the controlling may include: controlling the coding operation to the picture data from the macroblock corresponding to the error detected macroblock number to the macroblock corresponding to the recovered macroblock number in an intra mode.
In another aspect of the present invention, a method of coding picture data is attained by carrying out a coding operation of picture data; by demultiplexing coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
and by controlling the coding operation based on the error detected macroblock number and the recovered macroblock number from the demultiplexing section. In this case, the controlling may include: controlling the coding operation to the picture data from the macroblock corresponding to the error detected macroblock number to the macroblock corresponding to the recovered macroblock number in an intra mode.
In still another aspect of the present invention, a method of decoding picture data is attained by detecting an error from coded data; and by notifying an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error. In this case, the detecting may include: detecting the error from the demultiplexed coded data for every macroblock, and the notifying may include: notifying the error detected macroblock number to the another apparatus based on the detection of the coding error; determining whether the error continues; and notifying the recovered macroblock number to the another apparatus when the error is eliminated.
In an aspect of the present invention, there is provided a recording medium in which a program is recorded for either of the above-mentioned methods.
Brief Description of the Drawings Fig. 1 is a circuit block diagram showing a conventional coding and decoding system;
Fig. 2 is a circuit block diagram showing the structure of a picture coding and decoding apparatus according to an embodiment of the present invention;
Fig. 3 is a flow chart for describing a picture coding and decoding method in the embodiment of the present invention;
Fig. 4 is a diagram showing a picture block;
and Fig. 5 is a circuit block diagram showing the system configuration in the embodiment of the present invention.
Description of the Preferred Embodiments Hereinafter, a picture coding and decoding apparatus of the present invention will be described below in detail with reference to the attached drawings.
Fig. 2 is a block diagram showing the structure of the picture coding and decoding apparatus according to an embodiment of the present invention.
Referring to Fig. 2, the picture coding and decoding apparatus is composed of a picture coding section 1 and a picture decoding section 9. Input picture data 2 is supplied to the picture coding section 1. The picture coding section 1 carries out the coding operation of the input picture data 2 and outputs coded picture data 3.
The picture coding section 1 is connected with a multiplexing section 4. The multiplexing section 4 sends out to a transmission path, coded data 5 in which the coded picture data 3, coded sound data, and the other coded data are multiplexed. A
demultiplexing section 6 separates received coded data 7 in coded sound data, coded picture data 8, and the other coded data. The demultiplexing section 6 is connected with the picture decoding section 9. The picture decoding section 9 carries out a decoding operation of the coded picture data 8 and outputs a reconstructed picture 11.
Also, the picture coding and decoding apparatus is further composed of a macroblock number notifying section 12, a coding operation control section 13 and a coding information storage section 14.
The picture decoding section 9 outputs existence or non-existence 15 of a decoding error macroblock and a macroblock number 16 of the decoding error macroblock 15. The macroblock number notifying section 12 receives the existence or non-existence 15 of the decoding error macroblock and the macroblock number 16, and sends to the multiplexing section 4, the macroblock number 16E as an error start macroblock when the decoding error is detected and a macroblock number 16R as an error end macroblock when the decoding operation is revered to a normal state. The macroblock number 16 is multiplexed with the other coded data and is transmitted to another picture coding and decoding apparatus (not shown).
The demultiplexing section 6 is connected with the coding control section 13. The coding control section 13 receives the macroblock number 16E
of the error start macroblock and the macroblock number 16R of the error end macroblock through the demultiplexing section 6. The macroblock number 16E
of the error start macroblock and the macroblock number 16R of the error end macroblock are stored in the coding information storage section 14. The coding control section 13 refers to coding information such as intra-macroblock and a slice structure necessary to control the picture coding section 1. Also, the coding control section 13 store the coding information in the coding information storage section 14.
The picture decoding section 9 determines whether or not a decoding error has occurred during the decoding operation for every macroblock. The picture decoding section 9 notifies the determination result and the macroblock number 16 to the decoding error macroblock number notifying section 12. The determination of existence or non-existence 15 of the decoding error macroblock can be carried out based on the appearance of a symbol, which is not in a coding table, and the appearance of information which is hardly possible to appear. The macroblock number 16E
or 16R is allocated to allow the position of the macroblock to be recognized uniquely based on the number. For example, the macroblock numbers are allocated in a manner from the upper left of the picture data as a start point to the right and from the top to the bottom such as 1, 2, 3. The coding section and the decoding section share the same data.
Fig. 3 shows the operation of the decoding error macroblock number notifying section 12. When the picture decoding process is started, the macroblock number notifying section 12 receives an error determination result of a macroblock from the picture decoding section 9 (Step S1). Then, the macroblock number notifying section 12 determines the existence or non-existence of the decoding error.
When there is any decoding error, the macroblock number notifying section 12 sends out to the multiplexing section 4, the number 16E of the macroblock in which the coding error has first occurred (Step S2). Then, the macroblock number notifying section 12 continues the reception of the determination result carried out for every macroblock by the decoding section 9 (Step S3). While sending out the number 16E of the macroblock in which the decoding error is found to the multiplexing section 4, the macroblock number notifying section 12 waits for the number of a macroblock which has returned to the normal state with no decoding error. When receiving the normal macroblock, the macroblock number notifying section 12 sends out the number 16R of the error end macroblock (Step S4). Generally, the error end macroblock emerges at the synchronization point of the picture or the slice. However, when an error is mixed in the data at the synchronization point, the error macroblocks sometime emerges over a plurality of slices.
Fig. 4 shows the structure of the slices. The coding control section 13 stores the coding condition of the picture data in the coding information storage section 14. The coding condition contains information of the structure of the slice 21 and intra-refresh.
When there is no a decoding error, the coding control section 13 determines the structure of the slice 21 in the suitable way and carries out the intra-refresh operation.
When the error start macroblock number 16E
and the error end macroblock number 16R are received, the numbers of macroblocks between the macroblocks corresponding to the numbers 16E and 16R is stored.
Then, the picture coding section 1 is controlled to carry out the intra-refresh operation to the macroblocks for the stored numbers. A motion compensator (not shown) is controlled not to use the picture data contained in the error macroblocks in case of motion compensation of the macroblocks in the inter mode.
Fig. 4 shows the structure of a slice 21 of a coded picture data surrounded by a thick line. The mark indicates the macroblock 22 in which the decoding error has occurred and the ~ mark indicates the macroblock 23 which has returned to the normal state.
The coding control section 13 attaches a mark to the macroblocks between the error start macroblock to the error end macroblock. In Fig. 4, the D mark indicates the error macroblock.
When coding the next picture data, the picture coding section 1 is controlled to code the error macroblocks in the intra mode. The macroblocks to be coded in the inter mode other than the error macroblocks are controlled not to be used for the motion compensation of the picture data containing the error macroblocks.
Fig. 5 shows another embodiment in which the picture coding and decoding apparatus is realized by a program for a microprocessor. The program for picture coding and decoding operations is recorded on a recording medium 31. The recording medium 31 can be such as a magnetic disk and a semiconductor memory recording medium. The picture coding and decoding program is read by a microprocessor 32 from the recording medium 31 and used to control the operation of the microprocessor 32. The microprocessor 32 executes the above-mentioned steps shown in Fig. 3.
The data necessary for the decoding operation such as sequence information and a macroblock count are stored in a memory 33.
In the circuit block shown in Fig. 2, only a transmitting side or a receiving side is shown. The interactive communication becomes possible by use of the circuit block in the transmitting side and the receiving side. Thus, the TV conference system can be structured.
In the picture coding and decoding apparatus of the present invention, the numbers of the error start macroblock and error end macroblock are notified to a counter end. Therefore, influence such as the decrease of an allocatable code quantity to the normally coded picture data can be prevented.
Also, the error macroblocks in which an error has occurred are intra-refreshed so that the degraded picture returns quickly to a normal state. Moreover, the macroblocks in which the error did not occur are coded in the inter mode, although there is a limitation to motion compensation. Therefore, the increase of the code quantity can be suppressed, compared with the case where all the macroblocks are coded in the intra mode.
Claims (21)
1. A picture coding and decoding apparatus comprising:
a coding section which codes a picture data;
a demultiplexing section which demultiplexes a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
a coding control section which controls said coding section based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section;
an error detecting section which detects an error from the demultiplexed coded data; and a notifying section which notifies another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
a coding section which codes a picture data;
a demultiplexing section which demultiplexes a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
a coding control section which controls said coding section based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section;
an error detecting section which detects an error from the demultiplexed coded data; and a notifying section which notifies another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
2. The picture coding and decoding apparatus according to claim 1, wherein said error detecting section detects the error from the demultiplexed coded data for every macroblock, and said notifying section notifies said another error detected macroblock number to said another apparatus based on the detection of the coding error, determines whether the error continues, and notifies said another recovered macroblock number to said another apparatus when the error is eliminated.
3. The picture coding and decoding apparatus according to claim 1, wherein said coding control section controls said coding section to code said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
4. A picture coding apparatus comprising:
a coding section which codes picture data;
a demultiplexing section which demultiplexes coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated; and a coding control section which controls said coding section based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section.
a coding section which codes picture data;
a demultiplexing section which demultiplexes coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated; and a coding control section which controls said coding section based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section.
5. The picture coding apparatus according to claim 4, wherein said coding control section controls said coding section to code said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
6. A picture decoding apparatus comprising:
an error detecting section which detects an error from coded data; and a notifying section which notifies an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
an error detecting section which detects an error from coded data; and a notifying section which notifies an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
7. The picture decoding apparatus according to claim 6, wherein said error detecting section detects the error from the demultiplexed coded data for every macroblock, and said notifying section notifies said error detected macroblock number to said another apparatus based on the detection of the coding error, determines whether the error continues, and notifies said recovered macroblock number to said another apparatus when the error is eliminated.
8. A method of coding and decoding picture data comprising:
demultiplexing a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
controlling a coding operation based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section;
detecting an error from the demultiplexed coded data; and notifying another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
demultiplexing a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
controlling a coding operation based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section;
detecting an error from the demultiplexed coded data; and notifying another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
9. The method according to claim 8, wherein said detecting includes:
detecting the error from the demultiplexed coded data for every macroblock, and said notifying includes:
notifying said another error detected macroblock number to said another apparatus based on the detection of the coding error;
determining whether the error continues; and notifying said another recovered macroblock number to said another apparatus when the error is eliminated.
detecting the error from the demultiplexed coded data for every macroblock, and said notifying includes:
notifying said another error detected macroblock number to said another apparatus based on the detection of the coding error;
determining whether the error continues; and notifying said another recovered macroblock number to said another apparatus when the error is eliminated.
10. The method according to claim 8, wherein said controlling includes:
controlling said coding operation to said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
controlling said coding operation to said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
11. A method of coding picture data comprising:
carrying out a coding operation of picture data;
demultiplexing coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
and controlling said coding operation based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section.
carrying out a coding operation of picture data;
demultiplexing coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
and controlling said coding operation based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section.
12. The method according to claim 11, wherein said controlling includes:
controlling said coding operation to said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
controlling said coding operation to said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
13. A method of decoding picture data comprising:
detecting an error from coded data; and notifying an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
detecting an error from coded data; and notifying an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
14. The method according to claim 13, wherein said detecting includes:
detecting the error from the demultiplexed coded data for every macroblock, and said notifying includes:
notifying said error detected macroblock number to said another apparatus based on the detection of the coding error;
determining whether the error continues; and notifying said recovered macroblock number to said another apparatus when the error is eliminated.
detecting the error from the demultiplexed coded data for every macroblock, and said notifying includes:
notifying said error detected macroblock number to said another apparatus based on the detection of the coding error;
determining whether the error continues; and notifying said recovered macroblock number to said another apparatus when the error is eliminated.
15. A recording medium in which a program is recorded for a method of coding and decoding picture data, wherein said method comprises:
demultiplexing a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
controlling a coding operation based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section;
detecting an error from the demultiplexed coded data; and notifying another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
demultiplexing a coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
controlling a coding operation based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section;
detecting an error from the demultiplexed coded data; and notifying another error detected macroblock number indicative of a number of a macroblock in which the error is detected and another recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
16. The recording medium according to claim 15, wherein said detecting includes:
detecting the error from the demultiplexed coded data for every macroblock, and said notifying includes:
notifying said another error detected macroblock number to said another apparatus based on the detection of the coding error;
determining whether the error continues; and notifying said another recovered macroblock number to said another apparatus when the error is eliminated.
detecting the error from the demultiplexed coded data for every macroblock, and said notifying includes:
notifying said another error detected macroblock number to said another apparatus based on the detection of the coding error;
determining whether the error continues; and notifying said another recovered macroblock number to said another apparatus when the error is eliminated.
17. The recording medium according to claim 15, wherein said controlling includes:
controlling said coding operation to said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
controlling said coding operation to said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
18. A recording medium in which a program is recorded for a method of coding picture data, wherein said method comprises:
carrying out a coding operation of picture data;
demultiplexing coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
and controlling said coding operation based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section.
carrying out a coding operation of picture data;
demultiplexing coded data to output an error detected macroblock number indicative of a number of a macroblock in which an error has occurred and a recovered macroblock number indicative of a number of a macroblock in which the error has been eliminated;
and controlling said coding operation based on said error detected macroblock number and said recovered macroblock number from said demultiplexing section.
19. The recording medium according to claim 18, wherein said controlling includes:
controlling said coding operation to said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
controlling said coding operation to said picture data from the macroblock corresponding to said error detected macroblock number to the macroblock corresponding to said recovered macroblock number in an intra mode.
20. A recording medium in which a program is recorded for a method of decoding picture data, wherein said method comprises:
detecting an error from coded data; and notifying an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
detecting an error from coded data; and notifying an error detected macroblock number indicative of a number of a macroblock in which the error is detected and a recovered macroblock number indicative of the detected error has been eliminated, to another apparatus based on the detection of the coding error.
21. The recording medium according to claim 20, wherein said detecting includes:
detecting the error from the demultiplexed coded data for every macroblock, and said notifying includes:
notifying said error detected macroblock number to said another apparatus based on the detection of the coding error;
determining whether the error continues; and notifying said recovered macroblock number to said another apparatus when the error is eliminated.
detecting the error from the demultiplexed coded data for every macroblock, and said notifying includes:
notifying said error detected macroblock number to said another apparatus based on the detection of the coding error;
determining whether the error continues; and notifying said recovered macroblock number to said another apparatus when the error is eliminated.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30619999A JP2001128161A (en) | 1999-10-28 | 1999-10-28 | Device and method for encoding and decoding moving picture and recording method used for them |
| JP306199/1999 | 1999-10-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2325065A1 true CA2325065A1 (en) | 2001-04-28 |
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ID=17954205
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2325065 Abandoned CA2325065A1 (en) | 1999-10-28 | 2000-10-27 | Picture coding and decoding apparatus with less transmission amount |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP2001128161A (en) |
| CA (1) | CA2325065A1 (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3630474B2 (en) * | 1995-07-14 | 2005-03-16 | 沖電気工業株式会社 | Moving picture transmission system and moving picture transmission apparatus |
| JPH1169355A (en) * | 1997-08-20 | 1999-03-09 | Sharp Corp | Image transmitter |
-
1999
- 1999-10-28 JP JP30619999A patent/JP2001128161A/en active Pending
-
2000
- 2000-10-27 CA CA 2325065 patent/CA2325065A1/en not_active Abandoned
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| JP2001128161A (en) | 2001-05-11 |
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