JPH0993575A - Image expansion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the image expansion device with a simple circuit configuration by extracting a wait time of a succeeding picture from compressed data during a wait time till the expansion of a picture of the compressed image data is started in the image expansion device. SOLUTION: The image expansion device is made up of a vbv delay extract circuit 2 extracting a wait time, a 90kHz up-counter 13 counted up for each 90kHz, an adder 14 adding the wait time and the count and providing an output of a start time, a start time insert circuit 15 inserting the start time to compressed image data, a rate buffer 9 storing the compressed image data, a decode wait circuit 10 awaiting output of the compressed image data till the count value becomes equal to the start time, and a decoder 11 expanding the compressed image data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention describes, for each picture, waiting time from the input of the picture data to the start of decompression of data obtained by compressing a moving picture such as an MPEG video stream. The present invention relates to an image decompression device that decompresses data. More specifically, the present invention provides an image decompression device that realizes, with a simple circuit configuration, taking out the waiting time of the next picture from the compressed data during the waiting time until the decompression of a certain picture is started.

[0002]

2. Description of the Related Art An MPEG video stream has data called a picture header for each picture. The picture header has a 32-bit constant picture start code at the head, and includes a 16-bit unsigned integer called VBV_delay. In VBV_delay, the time that the decoder has to wait after receiving the last byte of the picture start code before decoding the image is shown as a 90 kHz clock number.

The MPEG video stream is composed of a plurality of pictures, and the data amount differs depending on the type of picture. FIG. 6 shows a configuration example of an MPEG video stream. In FIG. 6, I1 and I16 are I pictures encoded in one screen, P4, P7, P10, P13, P19, P22, and P.
25 and P28 are P pictures coded using I pictures, B2, B3, B5, B6, B8, B9, and B pictures.
11, B12, B14, B15, B17, B18, B2
0, B21, B23, B24, B26, B27, B29
And B30 are B pictures that are coded using I pictures and P pictures. In this example, the I picture data amount is about 8 times the B picture data amount, and the P picture data amount is about 2 times the B picture data amount.
Input this video stream at a constant rate in Figure 7,
The timing chart at the time of decoding and displaying every fixed time is shown. t1 is the input start time of the picture I1 in FIG.
T1 is the decoding start time of the picture I1 in FIG.
Similarly, t2 to t30 are pictures B2 to B30 in FIG.
Input start time, T2 to T25 are pictures B2 in FIG.
To B25 decoding start time.

FIG. 8 shows VBV__ after receiving the picture start code.
The block diagram of the circuit which starts decoding after the time shown by delay passes is shown. In FIG. 8, 1 is a video stream input terminal, 2 is a VBV_delay extraction circuit, and 3 to 8 are 90.
kHz down counter, 9 is a rate buffer, 10 is a decode wait circuit, 11 is a decoder, and 12 is an image data output terminal.

The video stream input from the input terminal 1 is VBV_delay extraction circuit 2 for VBV_delay extraction circuit 2.
_delay is taken out. Here, 10 as VBV_delay
Suppose 0 is taken out. The extracted VBV_delay is 9
One of the 0 kHz down counters 3 to 8 is loaded. The 90 kHz down counter loaded with VBV_delay is decremented every 90 kHz, and the count value is sent to the decode wait circuit 10. That is, the retrieved VBV_
99, 9 for every 100 to 90 kHz clock of delay
The count value is counted down to 8, 97 ... 1, 0, and the count value is sent to the decode wait circuit 10. On the other hand, VBV_
The video stream that has passed through the delay extraction circuit 2 is accumulated in the rate buffer 9. The video stream stored in the rate buffer 9 is read by the decode wait circuit 10. After detecting the last byte of the picture start code, the decode wait circuit 10 waits until the counter value of the 90 kHz down counter loaded with VBV_delay becomes 0. When the count value becomes 0, the video stream is sent to the decoder 11. Decoding processing is performed by the decoder 11, and the image data is output to the output terminal 1
2 is output.

In FIG. 8, the VBV_delay extraction circuit 2 outputs VBV_delay.
_delay is extracted and loaded into the 90 kHz down counter, and after the decode wait circuit 10 detects the last byte of the picture start code, during the waiting operation until the counter value of the 90 kHz down counter becomes 0, VBV_
When the delay extraction circuit 2 extracts the VBV_delay of the next picture, a new VBV_delay cannot be loaded into the 90 kHz down counter used during the waiting operation, so it is necessary to use a plurality of 90 kHz down counters. . The reason why six 90 kHz down counters are used in FIG. 8 will be described below. For example, the VBV_delay of the picture 11 is extracted and loaded into the 90 kHz down counter at t11 and 90 k in FIG.
The time when the count value of the Hz down counter becomes 0 and decoding starts is T11. Therefore, from time t11 to time T11, one 90 kHz down counter is used to count VBV_delay of the picture 11. on the other hand,
From time t11 to time T11, VBV_delay of picture 12 to picture 16 is extracted, and it is separated by 90k.
The Hz down counter is loaded. Therefore, time t11
From 6 to time T11, six 90 kHz down counters are required. Similarly in other sections, VBV_delay can be extracted during the waiting time with six 90 kHz down counters or less. Therefore, in the above example, six 90 kHz down counters are required.

[0007]

However, in the conventional image decompressor, when one VBV_delay is loaded, the count value of one 90 kHz down counter becomes 0.
I will monopolize until I become a new VB during the waiting time
Since it is necessary to prepare a plurality of 90 kHz down counters to load V_delay, there is a problem that the circuit configuration becomes complicated. Therefore, an object of the present invention is to reduce the number of counters by providing a new waiting time for each data.

[0008]

In order to solve the above-mentioned problems, the present invention provides a moving image including compressed image data, and starts decompression after inputting the image data. And a wait time extraction means for extracting a wait time described in the bit stream in an image decompression device that inputs a bit stream including a wait time until the waiting time elapses and decompresses the compressed image data after the elapse of the wait time. , A counter that increments the count value at every predetermined time determined by a time unit representing the waiting time, the waiting time extracted by the waiting time extraction means, and the current count value input from the counter Then, adding means for using the added value as a decoding start time for starting the expansion of the image data, and a decoding start time from the adding means Inputting the compressed data from the waiting time extracting means, inserting the decoding start time into the input compressed data, and inserting the decoding start time from the decoding start time inserting means. The memory for inputting and storing the compressed data, the compressed data into which the decoding start time is inserted from the memory, the current count value from the counter, and the decoding start time and the decoding start time inserted in the compressed data. Decoding weight means for outputting the compressed data when the current count values become equal, and a decoder for decompressing the compressed image data when the compressed data is input from the decoding weight means are provided. And

According to a second aspect of the present invention, in the image decompressing apparatus according to the first aspect, the waiting time extraction means extracts the waiting time and a picture start code at the beginning of one picture data of a bitstream is set. When the picture start code is input and the decoding start time inserting means inputs the picture start code, the decoding start time is inserted immediately after the picture start code.

According to a third aspect of the present invention, a bit stream including image data in which a moving image is compressed and a waiting time from the input of the image data to the start of decompression is input, and the waiting time elapses. In an image decompressing device for decompressing the compressed image data later, a waiting time extracting means for extracting a waiting time described in the bit stream, and a predetermined time determined by a time unit representing the waiting time. A counter for increasing the count value, the waiting time extracted by the waiting time extraction means, and the current counter value input from the counter are added, and the added value is started to start decoding of the image data. The addition means for setting the time, the decoding start time from the addition means, and the compressed data from the waiting time extraction means are input. Decoding start time replacing means for replacing the data describing the waiting time until the decompression start of the input compressed data with the decoding start time, and the waiting time is replaced with the decoding start time from the decoding start time replacing means. The memory for inputting and storing the compressed data, the compressed data in which the decode start time is described from the memory, and the current count value from the counter, and the decode start time described in the compressed data. Decoding weight means for outputting the compressed data when the current count values become equal, and a decoder for decompressing the compressed image data when the compressed data is input from the decoding weight means are provided. Characterize.

According to a fourth aspect of the present invention, in the image decompressing apparatus according to the third aspect, the waiting time extracting means extracts the waiting time and a picture start code at the beginning of one picture data of a bit stream is set. When the picture start code is input and the picture start code is input, the decoding start time is replaced with a wait time at a position separated by a fixed length from the picture start code.

According to a fifth aspect of the present invention, a moving image includes compressed image data, and a bit stream including a waiting time from the input of the image data to the start of decompression is input, and the waiting time elapses. In an image decompressing device for decompressing the compressed image data later, a waiting time extracting means for extracting a waiting time described in the bit stream, and a predetermined time determined by a time unit representing the waiting time. A counter for increasing the count value, the waiting time extracted by the waiting time extraction means, and the current count value input from the counter are added, and the added value is started for decoding to start the expansion of the image data. Addition means for setting the time and the decoding start time from the addition means are input and held, and the decoding start time is output in the input order. That a FIFO memory, and input the compressed data from said waiting time extracting means receives a memory for storing, the compressed data from said memory, said FIFO
Decode wait means for outputting the compressed data when the decode start time input from the memory is equal to the current count value input from the counter, and the compressed data when the compressed data is input from the decode wait means. And a decoder for expanding the image data.

[0013]

According to the image decompressing device of the present invention, a moving image includes a compressed image data, and a bit stream including a waiting time from the input of the image data to the start of decompression is input. Then, in the image decompression device that decompresses the compressed image data after the waiting time has elapsed, the waiting time is extracted by the waiting time extraction means 2 that extracts the waiting time described in the bit stream, and the waiting time is calculated. The counter 13 that increments the count value every predetermined time determined by the unit of time to be counted is counted, and the waiting time extracted by the waiting time extraction means 2 and the current count value input from the counter 13 are added. Then, the decoding start time for starting the expansion of the image data, which is the added value, is obtained by the adding means 14, and the adding means is added. 4, the decode start time is inputted, the compressed data is inputted from the waiting time extracting means 2, the decode start time is inserted into the inputted compressed data by the decode start time inserting means 15, and the decode start time inserting means is inputted. Input the compressed data with the decoding start time inserted from 15,
Compressed data stored in the memory 9 and having the decoding start time inserted from the memory 9 and the current count value from the counter 13 are input, and the decoding start time and the current count value inserted into the compressed data are When they become equal, the compressed data is output from the decode weight means 10, and when the compressed data is input from the decode weight means 10, the compressed image data is expanded by the decoder 11.

According to a second aspect of the present invention, there is provided the image decompression apparatus according to the first aspect, wherein the waiting time extracting means 2 extracts the waiting time and a picture at the head of one picture data of a bit stream. When a start code is input and the decoding start time inserting means 15 inputs the picture start code, the decoding start time is inserted immediately after the picture start code.

According to another aspect of the image decompressing apparatus of the present invention, a moving image includes compressed image data, and a bit stream including a waiting time from the input of the image data to the start of decompression is input and the waiting is performed. In the image decompression device that decompresses the compressed image data after the passage of time, the waiting time described in the bit stream is extracted by the waiting time extraction means 2, and the predetermined time is determined by the time unit representing the waiting time. The waiting time extracting means 2 counts by the counter 13 which increases the count value every time.
The waiting time extracted by the above is added to the current counter value input from the counter 13, the decoding start time for starting the expansion of the added image data, which is the added value, is obtained by the adding means 14, and the adding means is added. The decode start time is input from 14 and the waiting time extraction means 2
The compressed start time replacing means 20 replaces the data describing the waiting time until the start of decompression of the input compressed data with the decoding start time replacing means 20, and the decoding start time replacing means 20 waits for the waiting time. The compressed data whose time is replaced by the decode start time is input to and stored in the memory 9, and the compressed data in which the decode start time is described and the current count value from the counter 13 are input from the memory 9. When the decode start time described in the compressed data and the current count value become equal, the compressed data is output by the decode weight means 10, and when the compressed data is input from the decode weight means 10, the compression is performed. The decoded image data is expanded by the decoder 11.

According to a fourth aspect of the present invention, there is provided the image decompression apparatus according to the third aspect, wherein the waiting time extraction means 2 extracts the waiting time and the picture at the head of one picture data of the bit stream. When a start code is input and the decode start time replacing means 20 inputs the picture start code, the decode start time is replaced with the waiting time at a position separated by a fixed length from the picture start code.

According to a fifth aspect of the present invention, in the image decompressing device, a moving image includes compressed image data, and a bit stream including a waiting time from the input of the image data to the start of decompression is input, and the waiting is performed. In the image decompression device that decompresses the compressed image data after the passage of time, the waiting time described in the bit stream is extracted by the waiting time extraction means 2, and the predetermined time is determined by the time unit representing the waiting time. The waiting time extracting means 2 counts by the counter 13 which increases the count value every time.
The waiting time extracted by the above is added to the current count value input from the counter 13, and the decoding start time for starting the expansion of the added image data, which is the added value, is obtained by the adding means 14, and the adding means is added. 14, the decode start time is input and held, the decode start time is output by the FIFO memory 26 in the order of input, the compressed data is input by the memory 9 from the waiting time extraction means 2, stored, and stored from the memory 9. When the compressed data is input and the decode start time input from the FIFO memory 26 and the current count value input from the counter 13 become equal, the compressed data is output by the decode wait means 10 and the decode wait means 1
When the compressed data is input from 0, the compressed image data is expanded by the decoder 11.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to the drawings shown in FIGS. 1 and 2 are diagrams showing a first embodiment of the present invention. As shown in FIG. 1, the image decompression device has a video stream input terminal 1, VBV_delay
Extraction circuit 2, 90 kHz up counter 13, adder 1
4, a decode start time insertion circuit 15, a rate buffer 9, a decode wait circuit 10, a decoder 11, and an image data output terminal 12.

The VBV_delay extracting circuit 2 extracts VBV_delay from the video stream input from the video stream input terminal 1. Where VBV
It is assumed that 100 is taken out as _delay. 90 kHz
In the up counter 13, the count value when VBV_delay is taken out is output to the adder as the initial count value, and the initial count value and the count value that is incremented by 90 kHz from the initial count value are sent to the decode wait circuit 10. . Here, when 100 is extracted as VBV_delay in the VBV_delay extraction circuit 2, it is assumed that the count value of the 90 kHz up counter 13 is 1000. This 1000 is output to the adder as the initial count value, and the initial count value 1000 and the count values 1001 and 10 that are increased every 90 kHz thereafter.
02 ... 1100 are sent to the decode wait circuit 10. The adder 14 adds the initial count value and VBV_delay output from the 90 kHz up counter 13 and the VBV_delay extraction circuit 2, respectively, and outputs the added value to the decode start time insertion circuit 15 as the decode start time. That is, the initial count value 10
00 and VBV_delay100 add value 1100 is the decoding start time. The decode start time insertion circuit 15 adds the adder 14 immediately after the picture start code of the video stream input from the VBV_delay extraction circuit 2.
The decoding start time output from is inserted, and the video stream with the decoding start time inserted is output. FIG. 2 shows a video stream configuration diagram for explaining the operation of the decode start time insertion circuit. In FIG. 2, 16 is a video stream before the picture start code, 17 is a picture start code, 1
8 is the video stream after the picture start code,
Reference numeral 19 represents the decode start time inserted by the decode start time inserting circuit 15. It can be seen that the decode start time 19 is inserted between the picture start code 17 and the video stream 18 after the picture start code. When the decoding start time insertion circuit 15 finds the picture start code 17 in the input video stream, it inserts the decoding start time 19 immediately after the picture start code 17 and outputs it. The video stream in which the decoding start time is inserted is accumulated in the rate buffer 9, and the video stream accumulated in the rate buffer 9 is read by the decode wait circuit 10. The decode wait circuit 10 reads the video stream accumulated in the rate buffer 9, detects the last byte of the picture start code, and then detects the end of the video stream until the count value of the 90 kHz up counter 13 becomes equal to the decode start time read from the video stream. Waiting for output. That is, the process waits until the initial count value 1000 reaches the decode start time 1100. 9
When the count value of the 0 kHz up counter 13 becomes equal to the decoding start time read from the video stream, the video stream is sent to the decoder 11, the decoder 11 performs the decoding process, and the image data is output from the output terminal 12.

3 to 4 are diagrams showing a second embodiment of the present invention. In this embodiment, a decode start time replacing circuit 20 is used instead of the decode start time inserting circuit 15 of the first embodiment. The video stream input from the video stream input terminal 1 is VBV_dlay extracted by the VBV_delay extraction circuit 2 for each picture.
The elay is taken out. Here, 100 as VBV_delay
Is taken out. 90kHz up counter 13
At, the count value when VBV_delay is taken out is output to the adder as the initial count value, and the initial count value and 90 kH from the initial count value.
The count value incremented for each z is the decode wait circuit 1
Sent to 0. Here, in the VBV_delay extraction circuit 2, V
90 kHz when 100 is taken out as BV_delay
It is assumed that the count value of the up counter 13 is 1000. This 1000 is output to the adder as the initial count value, and the initial count value 1000 and count values 1001, 1002, ...
0 is sent to the decode wait circuit 10. Adder 14
Then, the initial count value and VBV_delay output from the 90 kHz up counter 13 and the VBV_delay extraction circuit 2 are added, and the added value is output to the decode start time replacement circuit 20 as the decode start time. That is, the initial count value of 1000 and VBV_delay
The decoding start time is the addition value 1100 with 100. Decode start time replacement circuit 20 is VBV_dela
Replace y with the decode start time and output. FIG.
A video stream configuration diagram for explaining the operation of the decode start time replacement circuit is shown in FIG. In FIG. 4, 16 is a video stream before the picture start code, 17 is a picture start code, 23 is a video stream between the picture start code and VBV_delay,
Reference numeral 24 represents VBV_delay, 25 is a video stream after VBV_delay, and 19 is a decode start time replaced from VBV_delay by the decode start time replacement circuit 20. The decode start time replacement circuit uses the picture start code 1 in the input bit stream.
When 7 is found, the picture start code 17 and VBV_delay 24 described in the compressed image data of each picture
The VBV_delay 24 is found by utilizing the fact that the bit stream between and has a fixed length, and the VBV_delay 24 is replaced with the decode start time 19. The video stream in which VBV_delay is replaced with the decoding start time is stored in the rate buffer 9, and the video stream stored in the rate buffer 9 is read by the decode wait circuit 10. The decode wait circuit 10 reads the video stream accumulated in the rate buffer 9, detects the last byte of the picture start code, and then outputs 90 kHz.
Until the count value of the up counter 13 becomes equal to the decode start time read from the video stream, the video stream output wait state is set. That is, the initial count value 1000 is the decode start time 1100.
It will be in a waiting state until. When the count value of the 90 kHz up counter 13 becomes equal to the decoding start time read from the video stream, the video stream is sent to the decoder 11, the decoder 11 performs the decoding process, and the image data is output from the output terminal 12.

FIG. 5 is a diagram showing a third embodiment of the present invention. In this embodiment, the decode start time replacement circuit 20 of the second embodiment is omitted, and a FIFO memory is added between the adder 14 and the decode wait circuit 10. The VBV_delay extraction circuit 2 extracts VBV_delay from the video stream input from the video stream input terminal 1. Where VBV_d
It is assumed that 100 is taken out as elay. In the 90 kHz up counter 13, the adder 1 sets the count value when VBV_delay is taken as the initial count value.
4 and the initial count value and the count value increased every 90 kHz from the initial count value are sent to the decode wait circuit 10. Where VBV_delay
When 100 is extracted as VBV_delay in the extraction circuit 2, it is assumed that the count value of the 90 kHz up counter 13 is 1000. This 1000 is output to the adder 14 as the initial count value, and the initial count value 1000 and the count value 100 increased every 90 kHz thereafter.
1, 1002 ... 1100 are decode wait circuits 1
Sent to 0. The adder 14 adds the initial count value and VBV_delay output from the 90 kHz up counter 13 and the VBV_delay extraction circuit 2, respectively,
The added value is output to the FIFO memory 26 as the decoding start time. That is, the initial count value of 1000 and VB
The value 1100 added to V_delay100 becomes the decoding start time and is output. The decode start time is accumulated in the FIFO memory 26 and read by the decode wait circuit 10 in the order of input. After the decode wait circuit 10 detects the last byte of the picture start code, the count value of the 90 kHz up counter 13 becomes F.
The video stream input until the decoding start time read from the IFO memory 26 becomes equal to the decoding start time is put in an output standby state. When the count value of the 90 kHz up counter 13 is equal to the decode start time, the video stream is output to the decoder 11. Thereafter, the decode wait circuit 10 reads the decode start time of the next picture from the FIFO memory 26 and similarly 90 kH.
It waits until the count value of the z-up counter 13 becomes equal to the decoding start time. Decoder 11
Decodes the video stream input from the decode wait circuit 10, and the image data is output from the output terminal 12.

The video stream is a rate buffer 9
And the video stream stored in the rate buffer 9 is read by the decode wait circuit 10. The decode wait circuit 10 reads the video stream accumulated in the rate buffer 9, detects the last byte of the picture start code, and then until the count value of the 90 kHz up counter 13 becomes equal to the decode start time read from the FIFO memory 26. Will be in the output waiting state. That is, the process waits until the initial count value 1000 reaches the decode start time 1100. When the count value of the 90 kHz up counter 13 becomes equal to the decode start time read from the FIFO memory 26, the video stream is sent to the decoder 11, the decoder 11 performs the decoding process, and the image data is output from the output terminal 12.

[0023]

According to the present invention, the waiting time until image expansion can be grasped without occupying a counter, so that the waiting time can be controlled by one counter, and the circuit configuration with one counter is simple. Image decompression device.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a first embodiment of the present invention.

FIG. 2 is a video stream configuration diagram for explaining the operation of a decode start time insertion circuit.

FIG. 3 is a circuit diagram showing a second embodiment of the present invention.

FIG. 4 is a video stream configuration diagram for explaining the operation of a circuit that replaces VBV_delay with a decode start time.

FIG. 5 is a circuit configuration diagram showing a third embodiment of the present invention.

[Fig. 6] Configuration example of MPEG video stream

7 is a timing diagram of input and decoding of the MPEG video stream of FIG.

FIG. 8 is a circuit configuration diagram showing a conventional image decompression device.

[Explanation of symbols]

1 Video Stream Input Terminal 2 vbv_delay Extraction Circuit 3 90 kHz Down Counter 4 90 kHz Down Counter 5 90 kHz Down Counter 6 90 kHz Down Counter 7 90 kHz Down Counter 8 90 kHz Down Counter 9 Rate Buffer 10 Decode Wait Circuit of First and Second Embodiments 10A Decode Wait Circuit of Third Embodiment 10P Decode Wait Circuit of Conventional Example 11 Decoder 12 Image Data Output Terminal 13 90 kHz Up Counter 14 Adder 15 Decode Start Time Insertion Circuit 16 Video Stream Before Picture Start Code 17 Picture Start Code 18 Picture Video stream after start code 19 Decode start time 20 Decode start time replacement circuit 23 pictures Video stream 26 FIFO memory of the video stream 24 vbv_delay 25 vbv_delay later between the start code and vbv_delay

Claims (5)

[Claims] 1. A moving image includes compressed image data, and a bit stream including a waiting time from the input of the image data to the start of decompression is input, and the compressed image is input after the waiting time elapses. In an image decompression device for decompressing data, a waiting time extraction means for extracting a waiting time described in the bit stream, and a counter for increasing a count value at every predetermined time determined by a time unit representing the waiting time. And an addition unit that adds the waiting time extracted by the waiting time extraction unit and the current count value input from the counter, and uses the added value as a decoding start time for starting the expansion of the image data. The decoding start time is input from the adding means, the compressed data is input from the waiting time extracting means, and the input compression data is input. A decoding start time inserting means for inserting the decoding start time into the data, a memory for inputting and storing the compressed data in which the decoding start time is inserted from the decoding start time inserting means, and a decoding start time from the memory. Decode wait means for inputting the compressed data inserted with the current count value from the counter, and outputting the compressed data when the decode start time inserted in the compressed data and the current count value are equal, An image decompression device, comprising: a decoder that decompresses the compressed image data when the compressed data is input from the decode weight means. 2. The image decompression device according to claim 1, wherein the waiting time extracting means extracts the waiting time and inputs a picture start code at the beginning of one picture data of a bitstream to start the decoding start. An image decompression device, wherein when the time inserting means inputs the picture start code, the decoding start time is inserted immediately after the picture start code. 3. A moving image includes compressed image data, and a bit stream including a waiting time from the input of the pixel data to the start of decompression is input, and the compressed image is input after the waiting time elapses. In an image decompression device for decompressing data, a waiting time extraction means for extracting a waiting time described in the bit stream, and a counter for increasing a count value at every predetermined time determined by a time unit representing the waiting time. And an addition unit that adds the waiting time extracted by the waiting time extraction unit and the current counter value input from the counter, and uses the added value as a decoding start time for starting the expansion of the image data. The decoding start time is input from the adding means, the compressed data is input from the waiting time extracting means, and the input compression data is input. Decoding start time replacing means for replacing the data describing the waiting time until the start of data expansion with the decoding start time, and compressed data in which the waiting time is replaced by the decoding start time from the decoding start time replacing means. A memory for inputting and storing, compressed data in which the decode start time is described from the memory, and a current count value from the counter,
Decode wait means for outputting the compressed data when the decode start time described in the compressed data is equal to the current count value, and the compressed wait data when the compressed data is input from the decode wait means An image decompression device comprising: a decoder for decompressing image data; 4. The image decompression device according to claim 3, wherein the waiting time extracting means extracts the waiting time and inputs a picture start code at the beginning of one picture data of a bitstream to start the decoding start. An image decompression device, wherein the time replacement means replaces, when the picture start code is input, a waiting time located at a fixed length away from the picture start code with a decoding start time. 5. A moving image includes compressed image data, and a bit stream including a waiting time from the input of the image data until the start of decompression is input, and the compressed image after the waiting time elapses. In an image decompression device for decompressing data, a waiting time extraction means for extracting a waiting time described in the bit stream, and a counter for increasing a count value at every predetermined time determined by a time unit representing the waiting time. And an addition unit that adds the waiting time extracted by the waiting time extraction unit and the current count value input from the counter, and uses the added value as a decoding start time for starting the expansion of the image data. , Inputting and holding the decode start time from the adding means,
FIFO for outputting the decoding start time in the order of input
A memory, a memory for inputting and storing the compressed data from the waiting time extracting means, a memory for inputting the compressed data from the memory, a decode start time input from the FIFO memory and a current count input from the counter Decoding weight means for outputting the compressed data when the values become equal, and a decoder for decompressing the compressed image data when the compressed data is input from the decoding weight means, are provided. Image decompressor.