JP3439361B2 - Image encoding device and moving image transmission system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image encoding device and a moving image transmission system for transmitting encoded image data via a network such as the Internet or a mobile communication network.

[0002]

2. Description of the Related Art With the spread of the Internet, there is an increasing demand for multi-services for simultaneously carrying voice data and video data in a network system such as the Internet. There is RTP (Real Time Protocol) as a protocol for such a real-time communication application on the Internet. TCP (Transmissio), which is usually used for Internet communication in real-time applications,
n Contoro l Protocol) does not require a complex protocol like provides. For example, in a voice reproduction algorithm, it is considered that it is more advantageous to allow data loss than to cause a long delay due to complicated TCP processing. That is, the order control service, redelivery service, delivery guarantee service, flow control, etc. provided by TCP are not required.

Therefore, RTP is used for transmission of real-time application data by UDP (User Datagr).
am Protocol) is generally used.
UDP is a simplification of TCP processing and performs data transfer in only one direction. Specifically, the sending terminal only sends data to the designated port, and UDP does not care about data discard, order reversal, flow control, etc., and the application is entirely responsible for dealing with these. In addition, UDP can perform multicast using a special IP address for one-to-many broadcast type applications such as voice conference and video conference. For these reasons UDP is suitable for real-time applications. RTP supports only one message type, a message for carrying application data.
This is sufficient to carry simple applications, but many real-time applications require feedback and other response messages. These functions are different protocols RTCP (Real Ti
me Control Protocol). RTCP defines five message types: sender report packet, receiver report packet, source description packet, leave message packet, and application-specific packet. By using this RTCP, delays such as a time stamp, the number of transmitted packets, the number of transmitted bytes, the number of discarded packets, and jitter can be fed back. This makes it possible to construct flexible real-time applications.

Considering the case of delivering a moving image as a real-time application, it is not realistic to deliver the moving image as it is because the amount of data is too large. Therefore, as a moving image compression method, ITU-T provides H.264. 261 and H.264. 263, from ISO, MPEG1, MPEG2, M
PEG4 and the like are recommended. Among these moving picture coding methods, H.264 is used as a method of coding at a very low bit rate. 263 and MPEG4. H. 263, MPE
The environment in which G4 is considered to be used is in the case of wireless networks such as the Internet and mobile phones. In the case of the Internet, a burst error such as packet loss may occur, and in the case of a wireless network, a bit error may occur in which the bit is inverted from the burst error such as packet loss.

Since such a situation in which burst errors and bit errors are likely to occur is taken into consideration, more error resistant tools are added as compared with other moving image coding systems. As one of such error tolerances, there is an algorithm that can divide an image into small slices and decode only the data included in each slice. H. In case of H.263, Annex K Slice Structur
emode and Annex R Independent
SegmentDecoding mode, M
For PEG4, Annex E Resyncron
ization. The former divides an image into slices having a plurality of macroblocks before encoding the image, and each slice is encoded independently of other slices. In the latter case, a threshold of data size is determined, coding is performed for each macroblock, and when the coded data size exceeds the threshold, a slice having a plurality of coded macroblocks up to then is used. The size of this slice has a great impact on compression efficiency and error resilience.

When the slice size is large, the reference area becomes large when performing motion compensation prediction, so that coding efficiency is improved, but error concealment becomes difficult when a burst error or packet loss occurs on the transmission path. On the contrary, when the slice size is small, the coding efficiency is reduced, but the error resistance against packet loss is improved. Therefore, H.264. Determining the slice size is an important issue when sending data encoded by H.263 or MPEG4 through a transmission line with a high error rate.

An example of this slice determination means is as follows:
It is described in JP-A-8-242445. In the image coding method described in this publication, the number of macroblocks in a slice of a video sequence is adaptively changed between a moving region and a still region inside the image, and a small number of macroblocks in the moving region of the image, In the still area of the image, encoded data of the slice layer is constructed by a large number of macroblocks, and a slice having the small number of macroblocks is set as a priority class with a small cell loss rate during ATM transmission. This is a method of transmitting a slice having a number of macroblocks as a non-priority class with a high cell loss rate.

Further, in Japanese Patent Laid-Open No. 7-107096, as a method of transmitting data with high priority and low priority, information transmitted in a low priority bit stream at a high cell loss level of an ATM network. Is adopted according to the cell loss rate of the network. Also, a two-layer video coding technique is used in which compression efficiency and image quality are improved when the network load is low, and cell loss recoverability is improved when the network load is high. The encoder, in response to a cell loss information signal generated by a remote decoder, selects the prediction mode used to encode the low priority bitstream and selects the prediction mode used in the low priority bitstream. Is performed by changing the arrangement of the slice-start synchronization code.

[0009]

In the conventional image coding apparatus, the resynchronization method shown in MPEG4 uses fixed-length slices, but since there is no means for controlling the slice code amount, the generated code is used. Since it is not possible to control the error resistance according to the amount, there is a problem that the influence of the transmission error becomes large.

In addition, H. The conventional slicing method shown in FIG. 263 allows slices of arbitrary length,
The code amount may be concentrated on a specific slice depending on the type of the image, and when the slice with the concentrated code amount is discarded, there is a problem that the image deteriorates significantly.

Further, the method disclosed in Japanese Patent Laid-Open No. 8-242445 has a problem that the number of macroblocks in a slice is determined from a moving area and a still area of an image. This is because the number of macroblocks in the motion area is small and thus the coding efficiency is reduced and the code amount is increased, but since there is no rate control for this, it is not practical in a line with a small line capacity.

Further, the method disclosed in Japanese Patent Laid-Open No. 8-242445 has a problem that the number of macroblocks in a slice is determined only from the moving area and the still area of the image. This is because the feedback information from the receiving side is not used and it is ineffective for changes in the network.

Further, the method described in Japanese Patent Laid-Open No. 7-107096 is premised on a two-layer video coding technique, but depending on the partner terminal, such a hierarchical coding technique may not be supported. There is a problem.

Further, the systems disclosed in Japanese Patent Laid-Open Nos. 8-242445 and 7-107096 presuppose the use of channels having different priorities, but such a function cannot be provided by the network. There is a problem that sometimes.

It is an object of the present invention to provide a moving picture coding apparatus and a moving picture transmission system capable of coding a moving picture into a high quality picture with high efficiency on a network where an error is likely to occur.

[0016]

In order to solve the above-mentioned problems, the invention according to claim 1 is used in an encoding means for compressing an information amount of an input video signal, and in this encoding means. Slice control means for controlling the slice structure,
Packet transmitting means for packetizing the bit stream encoded by the encoding means and transmitting it to the network, the encoding means having a motion detecting means, a code amount controlling means and a code amount measuring means, and the packet transmitting means being a line. The slice control means has a capacity detection means, the motion information calculation means for discriminating a motion area and a still area from the result of the motion detection means, and a code for measuring the code amount distribution in the screen from the result of the code amount measurement means. A volume distribution calculating means, a line capacity calculating means for calculating the line capacity from the line capacity detecting means, and a slice structure determining means for updating the slice structure from the results of the motion detecting means, the code amount measuring means, and the line capacity detecting means. and, especially that the movement detector performs motion detection with reference to the slice structure, the code amount control means for performing code amount control of each slice with reference to the slice structure To.

According to a second aspect of the present invention, in addition to the first aspect of the invention, a packet receiving means for receiving the packet discard rate from the image decoding device is further provided, and the slice structure determining means determines the packet discard rate. It is characterized in that the slice structure is determined as a new input.

According to a third aspect of the present invention, in the invention according to one of the first and second aspects, the packet receiving means or the image transmitting section for receiving the image observer's gaze region from the image decoding device is further observed. The slice structure determining means is characterized in that the slice structure determining means determines the slice structure by using the gaze area as a new input.

A fourth aspect of the invention is characterized in that, in the first aspect of the invention, the slice structure determining means determines the slice structure such that the generated code amounts in slice units are substantially equal.

According to a fifth aspect of the present invention, in the second aspect of the invention, the slice structure determining means determines the slice structure such that the generated code amounts in slice units are substantially equal.

According to a sixth aspect of the present invention, in the third aspect of the invention, the slice structure determining means allocates a large code amount to the gaze area, and the generated code amount in slice units is almost equal within the gaze area. The feature is that the slice structure is determined so as to be even.

According to a seventh aspect of the present invention, there is provided a moving image transmission system including an image encoding device and an image decoding device capable of decoding the output of the image encoding device,
An image coding apparatus includes a coding means for compressing an information amount of an input video signal, a slice control means for controlling a slice structure used by the coding means, and a bitstream coded by the coding means. Packetizing means for packetizing and transmitting to the network, the encoding means has a motion detecting means, a code amount controlling means and a code amount measuring means, and the packet transmitting means has a line capacity detecting means,
The slice control means is a motion information calculating means for discriminating a motion area and a still area from the result of the motion detecting means, a code amount distribution calculating means for measuring the code amount distribution in the screen from the result of the code amount measuring means, and a line. It has a line capacity calculating means for calculating the line capacity from the capacity detecting means, a motion detecting means, a code amount measuring means, and a slice structure determining means for updating the slice structure from the result of the line capacity detecting means, and the motion detecting means is The motion detection is performed by referring to the slice structure, and the code amount control means controls the code amount for each slice by referring to the slice structure.

According to an eighth aspect of the present invention, in the invention according to the seventh aspect, the image coding apparatus further includes packet receiving means for receiving the packet discard rate from the image decoding apparatus, and the slice structure determining means discards the packet. The feature is that the slice structure is determined by using the rate as a new input.

The invention described in claim 9 is the image coding apparatus according to any one of claims 7 and 8.
Further comprises a packet receiving means for receiving the gazing area of the image observer from the image decoding device or an area detecting means for detecting the gazing area of the image transmitting section, and the slice structure determining means sets the slice structure with the gazing area as a new input. It is characterized by making a decision.

According to a tenth aspect of the present invention, in the invention according to the seventh aspect, the slice structure determining means determines the slice structure such that the generated code amounts in slice units are substantially equal.

The eleventh aspect of the present invention is characterized in that, in the eighth aspect of the invention, the slice structure determining means determines the slice structure such that the generated code amounts in slice units are substantially equal.

According to a twelfth aspect of the present invention, in the invention according to the ninth aspect, the slice structure determining means allocates a large code amount to the gaze area, and the generated code amount in slice units is almost equal within the gaze area. The feature is that the slice structure is determined so as to be even.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the image coding apparatus according to the first embodiment of the present invention includes a coding unit 1, a slice control unit 2, and a packet sending unit 3. The encoding unit 1 includes a video signal input unit 10 and a DC
A T (discrete cosine transform) unit 11, a quantization unit 12, a variable length coding unit 13, a buffer unit 14, a rate control unit 15, an inverse quantization unit 16, an inverse DCT unit 17, and a video memory. Unit 18, motion detector 19, and motion compensator 20
And an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 23, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36.

First, the operation of the encoder 1 will be described. The DCT unit 11 outputs 8 to the input video signal.
The matrix operation of the DCT transform is performed for each block of × 8 pixels, and the transform coefficient is output to the quantization unit 12. The quantizer 12 quantizes the input transform coefficient and outputs the quantized transform coefficient. The characteristics of quantization are
It is controlled by the rate controller 15. The quantized transform coefficient is passed to the variable length coding unit 13 and subjected to entropy coding processing such as variable length coding and run length coding. On the other hand, the signal that has been subjected to the inverse quantization process in the inverse quantization unit 16 and decoded into the transform coefficient is subjected to the DCT inverse transform matrix operation in the inverse DCT unit 17, and the prediction error signal for P and B pictures, In the case of an I picture, a signal corresponding to a coded image signal is decoded. The adder 21 outputs a signal obtained by adding the prediction signal for P and B pictures, and a signal as it is for I picture. The output signal of the adding unit 21 is stored in the video memory unit 18. The output signal of the video memory unit 18 (the signal delayed by one frame of the encoded frame) is input to the motion detection unit 19.
The motion detector 19 detects a motion vector signal MV for each macroblock. At this time, motion detection can be performed using the slice information 101 input from the slice control unit 2 so that each slice or a plurality of slices can be independently decoded.

The motion vector signal MV is subjected to predetermined coding by the variable length coding unit 13. The motion compensation unit 20 performs motion compensation based on the motion vector signal MV input from the motion detection unit 19, and generates a motion compensation predicted image. This prediction signal is subjected to difference calculation with the image input by the addition unit 22, and the difference information is input to the DCT unit 11 and encoded in the same manner as above.

The coded data signal entropy-coded by the variable length coding unit 13 is input to the buffer unit 14, and its output signal is passed to the packet sending unit 3 as coded data. Further, the rate control unit 15 monitors the buffer and controls the quantization characteristic of the quantization unit 12 according to its state.

Next, the operation of the slice controller 2 will be described. The motion information calculator 26 is a motion detector 19 of the encoder 1.
The motion information 102 is received from and the motion information for each slice is calculated. The line capacity calculation unit 27 receives the line capacity information 104 input from the line capacity detection unit 36, and calculates the upper limit value of the optimum slice size. The code amount distribution calculation unit 28 receives the code amount information 103 from the buffer unit 14 of the encoding unit 1, and calculates the code amount for each macroblock or for each predetermined area unit. The slice structure determination unit 23 includes a motion information calculation unit 26 and a line capacity calculation unit 27.
And the slice structure is determined using the information from the code amount distribution calculator 28. The determined slice structure information 101 is sent to the motion detection unit 19 of the encoding unit 1. The slice structure information 101 is also sent to the rate control unit 15. The motion information calculator 26 receives the motion information 102 from the motion detector 19 of the encoder 1, calculates the motion information in each slice as shown in FIG. 13, and reduces the slice area when the motion in the slice is large. If the movement within the slice is small, the slice area is enlarged. As a result, the importance of each packet can be made uniform.

As the line capacity information 104 used by the line capacity calculator 27 to calculate the optimum slice size, specifically, the maximum transmission unit of a datagram to be sent on the network {MTU (Maximum Transmissis).
on Unit)}. When the packet size to be sent to the network exceeds this MTU, the packet is divided and transmitted as a plurality of datagrams on the network. In such a case, a packet created in consideration of error resilience is divided by the MTU size, resulting in a plurality of packets having weak error resilience.

Next, a case where a voice signal, a video signal, a control signal and the like are multiplexed by using the multiplexing method will be described. When a video signal is multiplexed, the video signal is divided into a certain data size and then multiplexed with other data, and thus the divided data size is preferably a unit having a certain meaning. Here, if the data divided for multiplexing is set in slice units, error resistance is enhanced when an error occurs in the multiplexed bitstream. Next, the case of transmission over an ATM network will be described. Even in the case of ATM transmission, error resilience can be enhanced by limiting the size of one slice within the size of the cell, which is the transmission unit. As described above, the maximum value of the packet size on the transmission path that occurs during transmission is very important from the viewpoint of error resilience. Therefore, the maximum value of the packet size is detected by the line capacity detection unit 36, and the line capacity information 104 is input to the slice control unit 2 to generate a slice having high error resistance.

The code amount distribution calculation unit 28 receives the code amount information 103 from the buffer unit 14 of the encoding unit 1, calculates the code amount for each macroblock as shown in FIG. 14, and calculates the code amount from the start of slice. Is the line capacity calculator 27
1 until the maximum value of the obtained slice size is exceeded
Cut into slices. In FIG. 13, the maximum slice size is set to 9, and the slice structure is dynamically changing. This makes it possible to control the code amount of one slice.

Next, the operation of the packet transmission section 3 will be described. The packet generator 35 sends the bitstream input from the encoder 1 to the network as a packet. The line capacity detecting unit 36 determines the maximum value of the packet size according to the network to which the packet is sent and the network condition by a method such as exchanging information with the network.

Next, a second embodiment of the present invention will be described in detail with reference to the drawings. In the second embodiment of the present invention, the same components as those of the first embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 2, the image encoding device according to the second embodiment of the present invention includes an encoding unit 1
And a slice control unit 2 and a packet transmission unit 3. The encoding unit 1 includes a video signal input unit 10 and a DCT.
(Discrete Cosine Transform) Unit 11, Quantization Unit 12, Variable Length Coding Unit 13, Buffer Unit 14, Rate Control Unit 1
5, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20,
It has an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 24, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28.
And a discard rate calculation unit 29. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36.

Next, the operation of the image coding apparatus as the second embodiment of the present invention will be described in detail. The operation of the encoding unit 1 is the same as the operation of the first exemplary embodiment of the present invention. Next, the operation of the slice controller 2 will be described. The discard rate calculation unit 29 receives the packet discard rate information 106. From the discard rate calculation unit 29, the packet discard rate is determined by the slice structure determination unit 24.
Entered in. When the packet discard rate is large, the slice structure determination unit 24 reduces the maximum value of the slice size, and reduces the packet size of each to strengthen the error resistance against the discard error. However, if the packet size is reduced, the error resistance is strengthened, but the code amount is increased, and the line load may be further increased.
The slice structure information 101 is output to the rate control unit 15 of FIG.
The rate control unit 15 that has received the slice structure information 101
Reduces the code amount adaptively considering the given slice structure. Conversely, if the packet discard rate is small,
The slice size is increased with the maximum value of the slice size input by the line capacity calculation unit 27 as the upper limit. By this operation, it is possible to perform the coding adapted to the fluctuation of the network line. The operation of the packet sending unit 3 is the same as the operation of the first embodiment.

Next, a third embodiment of the present invention will be described in detail with reference to the drawings. In the third embodiment of the present invention, the same components as those in the first and second embodiments of the present invention are designated by the same reference numerals. As shown in FIG. 3, the image coding apparatus according to the third embodiment of the present invention includes a coding unit 1, a slice control unit 2, and a packet sending unit 3. The encoding unit 1 includes a video signal input unit 10, a DCT (discrete cosine transform) unit 11, a quantization unit 12, a variable length encoding unit 13, a buffer unit 14,
Rate control unit 15, inverse quantization unit 16, and inverse DCT unit 1
7, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20, an addition unit 21, and an addition unit 22. The slice control unit 2 includes a slice structure determination unit 25,
The motion information calculation unit 26, the line capacity calculation unit 27, the code amount distribution calculation unit 28, the discard rate calculation unit 29, and the gaze area calculation unit 30 are included. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36.

Next, the operation of the image coding apparatus as the third embodiment of the present invention will be described in detail. The operation of the encoding unit 1 is the same as the operation of the first exemplary embodiment of the present invention. Next, the operation of the slice controller 2 will be described. The gaze area calculation unit 30 divides the image into a gaze area and a non-gaze area using the gaze area information 107 to generate division information. The division information of the gaze area calculation unit 30 is input to the slice structure determination unit 25. In the slice structure determination unit 25, the motion information calculation unit 26, the line capacity calculation unit 27, the code amount distribution calculation unit 28, and the discard rate calculation unit 29 determine the gaze area and the non-gaze area as shown in FIG. Distribute into different slices. The operation of the packet transmission unit 3 is the same as the operation of the first exemplary embodiment of the present invention. In the image coding apparatus according to the third embodiment of the present invention, the discard rate calculation unit 29 may be deleted.

Next, a fourth embodiment of the present invention will be described in detail with reference to the drawings. In the fourth embodiment of the present invention, the same components as those of the first embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 4, the image encoding device according to the fourth embodiment of the present invention includes an encoding unit 1
And a slice control unit 2 and a packet transmission unit 3. The encoding unit 1 includes a video signal input unit 10 and a DCT.
(Discrete Cosine Transform) Unit 11, Quantization Unit 12, Variable Length Coding Unit 13, Buffer Unit 14, Rate Control Unit 1
5, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20,
It has an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 23, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28.
And have. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36.

Next, the operation of the image coding apparatus according to the fourth embodiment of the present invention will be described in detail. The operation of the encoding unit 1 is the same as the operation of the first exemplary embodiment of the present invention. The operation of the slice control unit 2 differs from the operation of the first embodiment of the present invention in that the generated code amount for each slice is made substantially equal. By making the generated code amount for each slice almost equal, the slice size becomes smaller in the motion area and becomes larger in the still area. Therefore, if a packet is lost, the lost code amount is the same in both cases. Therefore, the influence on the image quality can be kept almost constant. The operation of the packet transmission unit 3 is the same as the operation of the first exemplary embodiment of the present invention.

Next, a fifth embodiment of the present invention will be described in detail with reference to the drawings. In the fifth embodiment of the present invention, the same components as those in the second embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 5, the image coding apparatus according to the fifth embodiment of the present invention includes a coding unit 1
And a slice control unit 2 and a packet transmission unit 3. The encoding unit 1 includes a video signal input unit 10 and a DCT.
(Discrete Cosine Transform) Unit 11, Quantization Unit 12, Variable Length Coding Unit 13, Buffer Unit 14, Rate Control Unit 1
5, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20,
It has an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 24, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28.
And a discard rate calculation unit 29. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36.

Next, the operation of the image coding apparatus as the fifth embodiment of the present invention will be described. The operation of the encoding unit 1 is
The operation is the same as that of the first exemplary embodiment of the present invention. The operation of the slice control unit 2 differs from the operation of the second embodiment of the present invention in that the generated code amount for each slice is made substantially equal. The operation of the packet transmission unit 3 is the first of the present invention.
The operation is the same as that of the above embodiment.

Next, a sixth embodiment of the present invention will be described in detail with reference to the drawings. In the sixth embodiment of the present invention, the same components as those in the third embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 6, the image encoding device according to the fifth embodiment of the present invention includes an encoding unit 1
And a slice control unit 2 and a packet transmission unit 3. The encoding unit 1 includes a video signal input unit 10 and a DCT.
(Discrete Cosine Transform) Unit 11, Quantization Unit 12, Variable Length Coding Unit 13, Buffer Unit 14, Rate Control Unit 1
5, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20,
It has an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 25, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28.
And a disposal rate calculation unit 29 and a gaze area calculation unit 30. The packet transmission unit 3 includes a packet generation unit 35,
It has a line capacity detector 36.

Next, the operation of the image coding apparatus as the sixth embodiment of the present invention will be described. The operation of the encoding unit 1 is
The operation is the same as that of the first exemplary embodiment of the present invention. The operation of the slice control unit 2 differs from the operation of the third embodiment of the present invention in that a larger code amount is allocated to the gazing area than to the non-gazing area. Further, the slice control unit 2 determines the slice structure such that the code amount in the slice is constant in both the non-gaze region and the gaze region, and controls the code amount. The operation of the packet transmission unit 3 is the same as the operation of the first exemplary embodiment of the present invention. In addition, in the image coding apparatus as the sixth embodiment of the present invention, the discard rate calculation unit 29 may be deleted.

Next, a seventh embodiment of the present invention will be described in detail with reference to the drawings. In the seventh embodiment of the present invention, the same components as those in the first embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 7, the moving image transmission system as the seventh exemplary embodiment of the present invention includes an encoding unit 1, a slice control unit 2, a packet sending unit 3, a packet receiving unit 4, and a decoding unit 5. It has and. The encoding unit 1 includes a video signal input unit 10, a DCT (discrete cosine transform) unit 11, a quantization unit 12, and a variable length encoding unit 13.
A buffer unit 14, a rate control unit 15, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18,
A motion detector 19, a motion compensator 20, an adder 21,
And an adder 22. The slice control unit 2 includes a slice structure determination unit 23, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36. The packet receiving unit 4
It has a receiver 40 and a bitstream generator 42. The decoding unit 5 includes a buffer unit 51, a variable length decoding unit 52, an inverse quantization unit 53, an inverse DCT unit 54, a video memory unit 55, a motion compensation prediction unit 56, and an addition unit 57. is doing.

Next, the operation of the moving picture transmission system as the seventh embodiment of the present invention will be described in detail. Encoding unit 1
The operations of the slice control unit 2 and the packet transmission unit 3 are
The operation is the same as that of the first exemplary embodiment of the present invention. The reception unit 40 of the packet reception unit 4 receives the packet 201 transmitted from the packet generation unit 35 of the packet transmission unit 3. The packet 201 received by the receiving unit 40 is passed to the bitstream generating unit 42, and the bitstream generating unit 42 reconstructs the bitstream from the packet. Bitstream 20 reconstructed by the bitstream generator 42
2 is stored in the buffer unit 51 of the decoding unit 5. The bit stream taken out from the buffer unit 51 is decoded by the variable length decoding unit 52 and sent to the inverse quantization unit 53. The inverse quantization unit 53 performs inverse quantization processing and decodes the signal into transform coefficients, and the inverse DCT unit 54 performs DCT inverse transform matrix calculation, and when the picture is an I picture, decodes a signal corresponding to a coded image signal. To do. In the case of P and B pictures, the motion compensation prediction unit 5 uses the image stored in the video memory unit 55.
Motion compensation is performed at 6, and the signals are decoded, added at the addition unit 57, and output as a video signal.

Next, an eighth embodiment of the present invention will be described in detail with reference to the drawings. In the eighth embodiment of the present invention, the same components as those in the second embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 8, the moving image transmission system as the second exemplary embodiment of the present invention includes an encoding unit 1, a slice control unit 2, a packet transmission unit 3, a packet reception unit 4, and a decoding unit 5. It has and. The encoding unit 1 includes a video signal input unit 10, a DCT (discrete cosine transform) unit 11, a quantization unit 12, and a variable length encoding unit 13.
A buffer unit 14, a rate control unit 15, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18,
A motion detector 19, a motion compensator 20, an adder 21,
And an adder 22. The slice control unit 2 includes a slice structure determination unit 24, a motion information calculation unit 26, a line capacity calculation unit 27, a code amount distribution calculation unit 28, and a discard rate calculation unit 29. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36. The packet reception unit 4 has a reception unit 41, a bitstream generation unit 42, and a transmission unit 43. The decoding unit 5
It has a buffer unit 51, a variable length decoding unit 52, an inverse quantization unit 53, an inverse DCT unit 54, a video memory unit 55, a motion compensation prediction unit 56, and an addition unit 57.

Next, the operation of the moving picture transmission system as the eighth embodiment of the present invention will be described in detail. Encoding unit 1
The operations of the slice control unit 2 and the packet transmission unit 3 are
The operation is the same as that of the second embodiment of the present invention. The reception unit 41 of the packet reception unit 4 receives the packet 201 transmitted from the packet generation unit 35 of the packet transmission unit 3.
The packet 201 received by the reception unit 41 is passed to the bitstream generation unit 42, and the bitstream generation unit 42 reconstructs the bitstream from the packets. Further, the packet discard rate information is sent from the receiver 41 to the transmitter 43. The packet discard rate information 106 is sent from the transmitter 43 to the discard rate calculator 29 of the slice controller 2. Bitstream 20 reconstructed by the bitstream generator 42
2 is stored in the buffer unit 51 of the decoding unit 5. Decoding section 5
The operation of is the same as the operation of the seventh embodiment of the present invention.

Next, a ninth embodiment of the present invention will be described in detail with reference to the drawings. In the ninth embodiment of the present invention, the same components as those in the third embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 9, the moving image transmission system according to the ninth exemplary embodiment of the present invention includes an encoding unit 1, a slice control unit 2, a packet sending unit 3, a packet receiving unit 4, and a decoding unit 5. It has and. The encoding unit 1 includes a video signal input unit 10, a DCT (discrete cosine transform) unit 11, a quantization unit 12, and a variable length encoding unit 13.
A buffer unit 14, a rate control unit 15, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18,
A motion detector 19, a motion compensator 20, an adder 21,
And an adder 22. The slice control unit 2 includes a slice structure determination unit 25, a motion information calculation unit 26, a line capacity calculation unit 27, a code amount distribution calculation unit 28, a discard rate calculation unit 29, and a gaze area calculation unit 30. is doing. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36. The packet receiving unit 4 has a receiving unit 41.
And a bitstream generation unit 42 and a transmission unit 43. The decoding unit 5 includes a buffer unit 51, a variable length decoding unit 52, an inverse quantization unit 53, an inverse DCT unit 54, a video memory unit 55, a motion compensation prediction unit 56, and an addition unit 5.
7 and 7. The moving image transmission system as the ninth exemplary embodiment of the present invention further includes a gaze area input device 71 connected to the gaze area calculation unit 30 and a gaze area input device 61 connected to the transmission unit 43. is doing.

Next, the operation of the moving picture transmission system as the ninth embodiment of the present invention will be described in detail. Encoding unit 1
The operations of the slice control unit 2 and the packet transmission unit 3 are
The operation is the same as that of the third exemplary embodiment of the present invention. The reception unit 41 of the packet reception unit 4 receives the packet 201 transmitted from the packet generation unit 35 of the packet transmission unit 3.
The packet 201 received by the reception unit 41 is passed to the bitstream generation unit 42, and the bitstream generation unit 42 reconstructs the bitstream from the packets. Further, the packet discard rate information is sent from the packet receiving section 41 to the sending section 43.
Sent to. The gazing area information 203 of the recipient obtained by the gazing area input device 61 is sent to the transmitting unit 43. The packet sending unit 43 sends the packet discard rate information 106 to the discard rate calculating unit 29 of the slice control unit 2 and the gaze area information 107 to the gaze area calculating unit 30 of the slice control unit 2.

The bit stream 202 reconstructed by the bit stream generation unit 42 is the buffer unit 51 of the decoding unit 5.
Stored in. The operation of the decoding unit 5 is the same as the operation of the seventh exemplary embodiment of the present invention. In the gaze area input device 71, the gaze area information 108 from the sender is sent to the gaze area calculator 30 of the slice controller 2. In addition, in the moving image transmission system as the ninth embodiment of the present invention, the discard rate calculation unit 29 may be deleted.

Next, a tenth embodiment of the present invention will be described in detail with reference to the drawings. In the tenth embodiment of the present invention, the same components as those in the fourth embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 10, the moving image transmission system as the tenth exemplary embodiment of the present invention includes an encoding unit 1, a slice control unit 2, a packet transmission unit 3, a packet reception unit 4, and a decoding unit 5. It has and. The encoding unit 1 includes a video signal input unit 10 and a DCT.
(Discrete Cosine Transform) Unit 11, Quantization Unit 12, Variable Length Coding Unit 13, Buffer Unit 14, Rate Control Unit 1
5, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20,
It has an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 23, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28.
And have. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36. The packet receiver 4 includes a receiver 40 and a bitstream generator 4
2 and. The decoding unit 5 includes a buffer unit 51, a variable length decoding unit 52, an inverse quantization unit 53, and an inverse DCT unit 5.
4, a video memory unit 55, a motion compensation prediction unit 56,
And an adder 57.

Next, the operation of the moving picture transmission system as the tenth embodiment of the present invention will be described. The operations of the encoding unit 1, the slice control unit 2, and the packet transmission unit 3 are the same as the operations of the fourth embodiment of the present invention. The operations of the packet receiving unit 4 and the decoding unit 5 are the same as the operations of the seventh embodiment of the present invention.

Next, an eleventh embodiment of the present invention will be described in detail with reference to the drawings. In the eleventh embodiment of the present invention, the same components as those in the fifth embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 11, the moving image transmission system as the eleventh exemplary embodiment of the present invention includes an encoding unit 1, a slice control unit 2, a packet transmission unit 3, a packet reception unit 4, and a decoding unit 5. It has and. The encoding unit 1 includes a video signal input unit 10 and a DCT.
(Discrete Cosine Transform) Unit 11, Quantization Unit 12, Variable Length Coding Unit 13, Buffer Unit 14, Rate Control Unit 1
5, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20,
It has an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 24, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28.
And a discard rate calculation unit 29. The packet transmission unit 3 has a packet generation unit 35 and a line capacity detection unit 36. The packet reception unit 4 has a reception unit 41, a bitstream generation unit 42, and a transmission unit 43. The decoding unit 5 includes a buffer unit 51 and a variable length decoding unit 5
2, an inverse quantization unit 53, an inverse DCT unit 54, a video memory unit 55, a motion compensation prediction unit 56, and an addition unit 57.

Next, the operation of the moving picture transmission system as the eleventh embodiment of the present invention will be described. The operations of the encoding unit 1, the slice control unit 2, and the packet transmission unit 3 are the same as the operations of the fifth embodiment of the present invention. The operation of the packet receiving unit 4 is the same as the operation of the eighth embodiment of the present invention. The operation of the decoding unit 5 is the same as the operation of the seventh exemplary embodiment of the present invention.

Next, a twelfth embodiment of the present invention will be described in detail with reference to the drawings. In the twelfth embodiment of the present invention, the same components as those in the ninth embodiment of the present invention are designated by the same reference numerals. As shown in FIG. 12, the moving image transmission system according to the twelfth exemplary embodiment of the present invention includes a coding unit 1, a slice control unit 2, a packet sending unit 3, a packet receiving unit 4, and a decoding unit 5. It has and. The encoding unit 1 includes a video signal input unit 10 and a DCT.
(Discrete Cosine Transform) Unit 11, Quantization Unit 12, Variable Length Coding Unit 13, Buffer Unit 14, Rate Control Unit 1
5, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20,
It has an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 25, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28.
And a disposal rate calculation unit 29 and a gaze area calculation unit 30. The packet transmission unit 3 includes a packet generation unit 35,
It has a line capacity detector 36. Packet receiver 4
Has a reception unit 41, a bitstream generation unit 42, and a transmission unit 43. The decoding unit 5 includes a buffer unit 51.
Variable length decoding unit 52, inverse quantization unit 53, and inverse DC
T unit 54, video memory unit 55, motion compensation prediction unit 5
6 and an addition unit 57. The moving image transmission system according to the twelfth embodiment of the present invention further includes a gaze area input device 71 connected to the gaze area calculation unit 30,
It has a gaze area input device 61 connected to the transmitter 43.

Next, the operation of the moving picture transmission system as the twelfth embodiment of the present invention will be described. The operations of the encoding unit 1, the slice control unit 2, and the packet transmission unit 3 are the same as the operations of the fourth embodiment of the present invention. The operation of the packet receiving unit 4 is the same as the operation of the ninth exemplary embodiment of the present invention. The operation of the decoding unit 5 is the same as the operation of the seventh exemplary embodiment of the present invention.

Next, a thirteenth embodiment of the present invention will be described in detail with reference to the drawings. In the thirteenth embodiment of the present invention, the same components as those in the twelfth embodiment of the present invention are designated by the same reference numerals. As shown in FIG.
The moving image transmission system as the thirteenth embodiment of the present invention includes an encoding unit 1, a slice control unit 2, a packet transmission unit 3, a packet reception unit 4, and a decoding unit 5. The encoding unit 1 includes a video signal input unit 10 and a DCT.
(Discrete Cosine Transform) Unit 11, Quantization Unit 12, Variable Length Coding Unit 13, Buffer Unit 14, Rate Control Unit 1
5, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20,
It has an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 25, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28.
And a disposal rate calculation unit 29 and a gaze area calculation unit 30. The packet transmission unit 3 includes a packet generation unit 35,
It has a line capacity detector 36. Packet receiver 4
Has a reception unit 41, a bitstream generation unit 42, and a transmission unit 43. The decoding unit 5 includes a buffer unit 51.
Variable length decoding unit 52, inverse quantization unit 53, and inverse DC
T unit 54, video memory unit 55, motion compensation prediction unit 5
6 and an addition unit 57. The moving image transmission system according to the twelfth embodiment of the present invention further includes a gaze area input device 71 connected to the gaze area calculation unit 30,
It has a gaze area input device 61 connected to the transmitter 43.

The moving picture transmission system as the thirteenth embodiment of the present invention is on the Internet. As a method of the encoding unit 1 and the decoding unit 5, the H.264 standard is used. 263, MP
For example, EG4. There is RTP as the packet sending unit 3 and RTCP as the packet sending unit 43 of the packet receiving unit 4. The encoding unit 1 receives the slice structure from the slice control unit 2 and encodes the input image based on the slice structure. The motion information calculation unit 26 receives the vertical and horizontal motion vectors from the motion detection unit 19 of the encoding unit 1. The line capacity calculator 27 receives the maximum value of the packet size on the network. The code amount distribution calculation unit 28 receives the code amount of each macroblock from the buffer unit 14 of the encoding unit 1. The discard rate calculator 29 receives the discard rate from the RTCP header. The gaze area calculation unit 30 determines whether each macroblock in the image is a gaze area or a non-gaze area.

The slice structure determining unit 25 determines the slice structure based on the respective input information, and the encoding unit 1
Input to the motion detection unit 19 of FIG. The packet sending unit 3 packetizes the received bit stream in a form that conforms to the RTP format and sends it to the network. The packet receiving unit 4 receives the RTP format packet and sends the packet to the bitstream generating unit 42.

Further, here, the information necessary for RTCP is calculated and sent to the transmitting section 43. The transmitter 43 receives the gaze area from the gaze area input device 61. The transmission unit 43 sends the RTCP format packet and the gaze area information to the transmission side. The bitstream generation unit 42 converts the packet into a bitstream and sends it to the decoding unit 5. The decoding unit 5 decodes the received bitstream and outputs an image.

Next, a fourteenth embodiment of the present invention will be described in detail with reference to the drawings. In the fourteenth embodiment of the present invention, the same components as those in the twelfth embodiment of the present invention are designated by the same reference numerals. As shown in FIG.
The moving image transmission system as the fourteenth embodiment of the present invention includes an encoding unit 1, a slice control unit 2, a packet transmission unit 3, a packet reception unit 4, and a decoding unit 5. The encoding unit 1 includes a video signal input unit 10 and a DCT.
(Discrete Cosine Transform) Unit 11, Quantization Unit 12, Variable Length Coding Unit 13, Buffer Unit 14, Rate Control Unit 1
5, an inverse quantization unit 16, an inverse DCT unit 17, a video memory unit 18, a motion detection unit 19, a motion compensation unit 20,
It has an adder 21 and an adder 22. The slice control unit 2 includes a slice structure determination unit 25, a motion information calculation unit 26, a line capacity calculation unit 27, and a code amount distribution calculation unit 28.
And a disposal rate calculation unit 29 and a gaze area calculation unit 30. The packet transmission unit 3 includes a packet generation unit 35,
It has a line capacity detector 36. Packet receiver 4
Has a reception unit 41, a bitstream generation unit 42, and a transmission unit 43. The decoding unit 5 includes a buffer unit 51.
Variable length decoding unit 52, inverse quantization unit 53, and inverse DC
T unit 54, video memory unit 55, motion compensation prediction unit 5
6 and an addition unit 57. The moving image transmission system according to the twelfth embodiment of the present invention further includes a gaze area input device 71 connected to the gaze area calculation unit 30,
It has a gaze area input device 61 connected to the transmitter 43.

The moving picture transmission system according to the fourteenth embodiment of the present invention is on a mobile communication network. As a method of the encoding unit 1 and the decoding unit 5, the H.264 standard is used. 263, MPE
There is G4 etc. As the transmission unit 43 of the packet transmission unit 3 and the packet reception unit 4, H.264 of ITU is used. 223, and H.H.
H.223 transmitted over H.223. There are 245. H. Two
H.23 is a multiplexing system. 245 is a signaling method.

The encoding unit 1 receives the slice structure from the slice control unit 2 and encodes the input image based on the slice structure. The motion information calculation unit 26 receives the vertical and horizontal motion vectors from the motion detection unit 19 of the encoding unit 1. In the line capacity calculation unit 27, the maximum value of the packet size on the line is set to H.264. 245 f
orward Maximum SDU Size,
backward Maximum SDU Size
Received by command. The code amount distribution calculation unit 28 receives the code amount of each macroblock from the buffer unit 14 of the encoding unit 1.

The discard rate calculation unit 29 uses the H.264 standard. 245 H22
3Multiplex Reconfiguratio
The discard rate information is received by the n command or the like, and the discard rate is calculated. Here, H. 223 Multiplex R
The configuration command is based on H.264 based on the error occurrence frequency on the line. Since the error resilience mode of 223 itself is strengthened or weakened, a value almost equivalent to the discard rate can be calculated by this command. In addition, H. 263 Annex N
Reference Picture Selecti
In on Mode, error information in the image can be notified from the receiving side to the transmitting side. The discard rate can also be calculated based on this notification information.

The gaze area calculation unit 30 determines whether each macroblock in the image is a gaze area or a non-gaze area. Alternatively, the above Annex N Ref
Rence Picture Selection M
By using the ode, the receiver can intentionally increase the code amount allocation by disguising the gaze area as a discard area. The slice structure determination unit 25 determines the slice structure based on each input information and inputs it to the motion detection unit 19 of the encoding unit 1. The packet sending unit 3 sends the received bit stream to H.264. H.223 packetizing in a form suitable for the data defined in H.223. It is sent to the multiplexer defined by H.223.

The packet receiving unit 4 receives the packet from the multiplexed data, and the bit stream generating unit 42
Send a packet to. In the transmission unit 43, the gazing area input device 6
Receive a gaze area from 1. The transmitting unit 43 sends an H.264 signal to the transmitting side. 245 H223 Multiplex Rec
The configuration command and the gaze area information are sent. The bitstream generation unit 42 converts the packet into a bitstream and sends it to the decoding unit 5. The decoding unit 5 decodes the received bitstream and outputs an image.

In the embodiment of the present invention, since the unit for controlling the code amount of the slice is provided, the error resilience can be controlled according to the generated code amount, and the influence of the transmission error can be controlled. . Further, in the embodiment of the present invention, the maximum value of one slice size can be set to a size suitable for each network, so that packet division in a layer below the image encoding device can be avoided.
Further, in the embodiment of the present invention, since the coding rate is used by the coding apparatus as the feedback information from the receiving side to perform coding, it is possible to perform coding corresponding to the fluctuation of the network line. Further, in the embodiment of the present invention, by using the gaze area information which is the feedback information from the receiving side and the gaze area information on the transmitting side, the important point and the unimportant point for the sender and the receiver are coded separately. The encoding device can perform the encoding.

[0071]

According to the present invention, the error resistance can be controlled in accordance with the generated code amount to minimize the influence of the error. Therefore, the moving image can be efficiently produced on the network where the error is likely to occur. It can be encoded into high quality images.

[Brief description of drawings]

FIG. 1 is a block diagram showing an image encoding device as a first embodiment of the present invention.

FIG. 2 is a block diagram showing an image encoding device as a second embodiment of the present invention.

FIG. 3 is a block diagram showing an image encoding device as a third embodiment of the present invention.

FIG. 4 is a block diagram showing an image encoding device as a fourth embodiment of the present invention.

FIG. 5 is a block diagram showing an image encoding device as a fifth embodiment of the present invention.

FIG. 6 is a block diagram showing an image coding apparatus as a sixth embodiment of the present invention.

FIG. 7 is a block diagram showing a moving image transmission system as a seventh embodiment of the present invention.

FIG. 8 is a block diagram showing a moving image transmission system as an eighth embodiment of the present invention.

FIG. 9 is a block diagram showing a moving image transmission system as a ninth embodiment of the present invention.

FIG. 10 is a block diagram showing a moving image transmission system as a tenth embodiment of the present invention.

FIG. 11 is a block diagram showing a moving image transmission system as an eleventh embodiment of the present invention.

FIG. 12 is a block diagram showing a moving image transmission system as a twelfth embodiment of the present invention.

FIG. 13 is a diagram for explaining the operation of the slice controller in FIGS. 1 to 12.

FIG. 14 is another diagram for operating the slice control unit in FIGS.

15 is a diagram for explaining a gaze area in FIGS. 3, 6, 9, and 12. FIG.

[Explanation of symbols]

1 Encoding section 2 slice controller 3 Packet transmitter 4 Packet receiver 5 Decoding section 10 Video signal input section 11 DCT section 12 Quantizer 13 Variable length coding unit 14 buffer section 15 Rate control unit 16 inverse quantizer 17 Inverse DCT section 18 Video memory section 19 Motion detector 20 Motion compensation section 21,22 Adder 23 to 25 slice structure determination unit 26 Motion Information Calculation Unit 27 Line capacity calculator 28 Code amount distribution calculator 29 Disposal rate calculator 30 Gaze area calculator 35 Packet Generator 36 Line capacity detector 40, 41 Receiver 42 Bitstream generator 43 Transmitter 51 buffer section 52 Variable Length Decoding Unit 53 inverse quantizer 54 Inverse DCT section 55 Video memory section 56 Motion Compensation Prediction Unit 57 Adder 61, 71 gazing area input device

   ─────────────────────────────────────────────────── ─── Continued front page       (56) References JP-A-7-107458 (JP, A)                 JP-A-6-351006 (JP, A)                 JP-A-8-1007096 (JP, A)                 JP-A-6-319134 (JP, A)                 Japanese Patent Laid-Open No. 10-164572 (JP, A)                 JP-A-8-331559 (JP, A)                 Special table flat 8-511931 (JP, A)

Claims (12)

(57) [Claims] 1. A coding means for compressing an information amount of an input video signal, a slice control means for controlling a slice structure used by the coding means, and a bit stream coded by the coding means. Packetizing means for packetizing and transmitting to the network, the encoding means has a motion detecting means, a code amount controlling means and a code amount measuring means, and the packet transmitting means has a line capacity detecting means, The slice control means, a motion information calculation means for discriminating a motion area and a still area from the result of the motion detection means,
Code amount distribution calculating means for measuring the code amount distribution in the screen from the result of the code amount measuring means, line capacity calculating means for calculating the line capacity from the line capacity detecting means, the motion detecting means and the code amount measuring Means and a slice structure determining means for updating the slice structure from the result of the line capacity detecting means, the motion detecting means performs motion detection with reference to the slice structure, and the code amount controlling means has the slice structure. The image coding apparatus is characterized in that the code amount is controlled for each slice with reference to. 2. The image coding apparatus according to claim 1, further comprising packet receiving means for receiving a packet discard rate from the image decoding apparatus, wherein the slice structure determining means slices the packet discard rate as a new input. The image coding apparatus according to claim 1, wherein the structure is determined. 3. The image coding apparatus according to claim 1 or 2, further comprising: detecting a gazing area of a packet receiving unit or an image transmitting unit that receives a gazing area of an image observer from the image decoding apparatus. An image coding apparatus, comprising: a region detecting unit that determines the slice structure, wherein the slice structure determining unit determines a slice structure using the gaze region as a new input. 4. The image coding apparatus according to claim 1, wherein the slice structure determining unit determines the slice structure such that the generated code amounts in slice units are substantially equal. apparatus. 5. The image coding apparatus according to claim 2, wherein the slice structure determining unit determines the slice structure such that the generated code amounts in slice units are substantially equal. apparatus. 6. The image coding apparatus according to claim 3, wherein the slice structure determining unit allocates a large amount of code to the gaze area, and the generated code amount in slice units is within the gaze area. An image coding apparatus characterized in that a slice structure is determined so as to be substantially equal. 7. A moving image transmission system comprising an image encoding device and an image decoding device capable of decoding the output of the image encoding device, wherein the image encoding device comprises:
Encoding means for compressing the amount of information with respect to the input video signal, slice control means for controlling the slice structure used in this encoding means, and packetizing the bit stream encoded by the encoding means into a network. And a packet sending means for sending to, the coding means has a motion detecting means, a code amount controlling means and a code amount measuring means, the packet sending means has a line capacity detecting means, and the slice controlling means is A motion information calculation means for discriminating a motion area and a still area from the result of the motion detection means,
Code amount distribution calculating means for measuring the code amount distribution in the screen from the result of the code amount measuring means, line capacity calculating means for calculating the line capacity from the line capacity detecting means, the motion detecting means and the code amount measuring Means and a slice structure determining means for updating the slice structure from the result of the line capacity detecting means, the motion detecting means performs motion detection with reference to the slice structure, and the code amount controlling means has the slice structure. The video transmission system is characterized in that the code amount control is performed for each slice with reference to. 8. The moving picture transmission system according to claim 7, wherein the image coding device further comprises packet receiving means for receiving a packet discard rate from the image decoding device, and the slice structure determining means comprises the packet discarding means. A moving image transmission system characterized in that a slice structure is determined using a rate as a new input. 9. The moving image transmission system according to claim 7, wherein the image coding device further receives a packet receiving means or an image for receiving a gaze region of an image observer from the image decoding device. A moving image transmission system comprising: an area detection unit that detects a gaze area of a transmission unit, wherein the slice structure determination unit determines a slice structure using the gaze area as a new input. 10. The moving image transmission system according to claim 7, wherein the slice structure determining means determines the slice structure so that the generated code amounts in slice units are substantially equal. system. 11. The moving image transmission system according to claim 8, wherein the slice structure determining unit determines the slice structure so that the generated code amounts in slice units are substantially equal. system. 12. The moving image transmission system according to claim 9, wherein the slice structure determination unit allocates a large code amount to the gaze area, and the generated code amount in slice units is inside the gaze area. A moving image transmission system characterized in that a slice structure is determined so as to be substantially equal.