JPH08331514A - Fast feed reproducing device for dynamic image - Google Patents

Abstract

PURPOSE: To provide a fast feeding reproducing device for a dynamic image not requiring excess data decoding or frame selection processing in response to a reproduction speed. CONSTITUTION: This reproducing device is provided with a usual image memory 21 storing a usual image formed by consecutive frame groups each consisting of an independent frame and a prescribed number of dependent frames succeeding to the independent frame, a fast feed image memory 22 storing the independent frames only arranged in time series among the consecutive frame groups, a fast rewinding image memory 23 storing the independent frames arranged in reverse time series, and when an instruction of fast feed is received from a terminal equipment section, data are read from the fast feed image memory 22 and when a command of fast rewinding is received from the terminal equipment section, data are read from the fast rewinding image memory 23 and the video image is displayed respectively by the terminal equipment section to obtain the fast feeding or fast rewinding image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving picture fast-forwarding reproducing apparatus, and more particularly to a moving picture fast-forwarding reproducing apparatus which decodes coded and compressed moving image data to perform fast-forwarding reproduction.

[0002]

2. Description of the Related Art There is known a moving image fast-forward reproducing apparatus which decodes data obtained by encoding and compressing a moving image signal and reproduces it fast-forwarding.

Conventionally, there are two known image coding methods, an intra-frame coding method and an inter-frame coding method. The intra-frame coding method independently codes a signal for one frame, whereas the inter-frame coding method predicts the signal of the frame to be coded from the signal of the previous frame and It only encodes.

Particularly in a moving image, since the image data of consecutive frames are similar to each other, the correlation is very strong, and the inter-frame coding method is effective for data compression.

However, according to this interframe coding method, when it is attempted to decode a specific one frame out of continuous frames, all past data is required.

In order to solve this drawback, (1) Japanese Unexamined Patent Publication (Kokai) No. 2
-192378 and (2) JP-A-2-2858.
Japanese Unexamined Patent Publication No. 16 discloses a predictive coding system of the MPEG system.

In these predictive coding schemes, independent frames that are independently coded at arbitrary intervals are inserted into the predictively coded frames, and predictive coding is performed based on the preceding and following independent frames. .

In this MPEG system, each frame is I
It is composed of a picture (independent frame), a P picture and a B picture (non-independent frame). Here, since the I picture corresponds to an independent frame, this picture is coded independently. On the other hand, the P picture and the B picture correspond to non-independent frames and thus cannot be encoded independently. Therefore, the P picture is coded based on the previous I picture or P picture, and the B picture is encoded before or after the previous I picture or P picture.
It is encoded based on the picture.

The fast-forward reproduction is performed by extracting and reproducing only the I picture, the P picture, or the B picture from the continuous frames at regular intervals.

Further, (3) Japanese Patent Application Laid-Open No. 5-344494 discloses another fast-forward playback system for MPEG moving images.

In this fast-forward reproduction method, rather than taking out and reproducing a predetermined picture at regular intervals, an I picture (independent frame) close to a predetermined picture at regular intervals is selected and only that I picture is taken out and reproduced. Was there.

[0012]

However, in the prior arts (1) and (2), if the frame to be extracted is an I picture, decoding can be performed using only that frame, but if it is a P picture or a B picture, However, it is necessary to simultaneously decode the adjacent frames used for prediction for decoding.

Further, in the case of fast-forward reproduction, it becomes necessary to select frames to be displayed at regular intervals according to the fast-forward speed multiplication factor, from among consecutive frames. However, the interval between the frames to be selected does not always match the interval between the independent frames. For this reason, in fast-forward reproduction in the MPEG system, it was necessary to always decode much more pictures than the number of pictures of a frame to be displayed, and select and display data at fixed intervals from them. Therefore, there is a drawback that the processing is complicated and takes a lot of time.

In the prior art (3), since only the I picture (independent frame) is taken out, the processing is simplified and the processing time is shortened as compared with the prior arts (1) and (2). , If the frame to be displayed is a non-independent frame such as P picture and B picture, it is necessary to perform I picture selection processing in order to display the I picture near it, and in this case, fast-forward reproduction at equal intervals. It had the drawback of not becoming.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a moving picture fast-forward reproducing apparatus which does not require decoding of extra data and frame selection processing depending on the reproducing speed.

[0016]

In order to solve the above-mentioned problems, the present invention provides a moving image composed of an independent frame coded by an intra-frame coding system and a non-independent frame coded by an inter-frame coding system. An image fast-forward reproduction apparatus, wherein moving image data for normal reproduction formed by a series of a frame group consisting of at least one independent frame and a fixed number of non-independent frames following the frame, and only independent frames from the frame group Of the image data for fast-forwarding formed by arranging the data in a time series and storing the moving image data for the normal reproduction and the fast-forwarding, and the moving image for the normal reproduction or the fast-forwarding from the storage means. And a read control means for selectively reading the image data.

[0017]

[Function] A moving image frame for normal reproduction is formed by a series of frames consisting of one independent frame and a fixed number of non-independent frames, and only the independent frames are extracted from this frame and arranged in time series. The fast-forwarding data is stored in the storage means. When performing fast-forward reproduction, the fast-forward data is read from this storage means and reproduced by a normal moving image reproducing apparatus.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram of an embodiment of a fast-forwarding reproduction apparatus for moving images according to the present invention. The fast-forward playback device for moving images is a device used for multimedia communication. The user selects a playback mode and plays back the moving image in a mode according to the selection. A multimedia communication server unit (hereinafter referred to as a server unit) 20 that transfers a predetermined moving image to the terminal 1 according to an instruction.

Further, the terminal unit 1 includes a host CPU 2 for executing a program according to a user's instruction, and a host CPU
In order to transfer the moving image data in the predetermined reproduction mode to the server unit 20 in accordance with the instruction from 2, the control signal transmitting unit 3 that transmits the control signal to the server unit 20 and the data transferred from the server unit 20 to the header unit ( System data processing unit 4 for classifying into time code), image, voice, etc., image data storage unit 5 for storing image data output from the system data processing unit 4, and image data stored in the image data storage unit 5. Decoding unit 6, an NTSC encoder 7 for converting the image data decoded by the decoding unit 6 into an NTSC signal, and an NTSC encoder 7 for N
A CP connected between the video display unit 8 for displaying the image data converted into the TSC signal, the host CPU 2, the control signal transmission unit 3, the system data processing unit 4 and the decoding unit 6.
It consists of a U-bus 9.

Next, the structure of the server unit will be described.
FIG. 2 is a block diagram of an embodiment of the server unit. Server part 2
0 is a normal image memory 21 that stores moving image data for normal reproduction, a fast-forward image memory 22 that stores moving image data for fast-forwarding, a fast-rewind image memory 23 that stores moving-image for fast-rewinding, Any one of these three memories 21 to 23 according to the control signal from the control signal communication unit 3
The read control unit 24 reads predetermined moving image data from each piece and transfers the read moving image data to the system data processing unit 4.

Although not shown, these three memories 2
1 to 23 is composed of a readable / writable memory (RAM, etc.),
By providing the server unit 20 with a known write control unit for writing predetermined moving image data in the memories 21 to 23, the latest moving image data can be fast-forwarded and reproduced.

Next, the data structure of moving image data will be described. FIG. 3 is a schematic explanatory view showing the data structure of moving image data.

GOP1 represents one frame group, and includes a leading I picture I00 (independent frame) and P pictures P03, P06, P09, P predicted and coded from the I picture I00.
0C and B pictures B01, B02, B04, B0
5, B07, B08, B0A, B0B, B0D, B0E
It is composed of a total of 15 pictures. Where GOP
Although the number of pictures of 1 is 15 as a general numerical value, it may be any number. In addition, the cycle of I and P pictures is 3
However, this may be any number.

A series of this one frame group (GO
P1, GOP2, ... GOPN; N is a positive integer of 2 or more)
The moving image data for normal reproduction is constituted by.

Here, GOP stands for Group of Pi
GOP is an abbreviation of "ctures", which means a data structure in which several pieces of image data are grouped together, an I picture is an intra-frame encoded image, a P picture is an inter-frame forward prediction encoded image, and a B picture. Means an inter-frame bidirectional predictive coded image, respectively.

The moving image data for fast-forwarding is GOP1.
~ I picture in the data of GOPN (independent frame)
I00, I10, ... IN0 are arranged continuously in time series.

The moving image data for fast rewinding is the reverse of the moving image data for fast forward IN0, ..., I10, I0.
They are arranged in the order of 0.

Next, the operation of the moving image fast-forward reproducing apparatus will be described.

First, the operation of the fast-forward reproduction display will be described. FIG. 4 is a schematic explanatory view showing the operation timing of the fast-forward reproduction display. The figure shows operation timings of the server section 20, the terminal section 1, the image data storage section 5, and the video display section 8 in order from the left, and shows that time progresses from the upper side to the lower side of the figure. In addition, S11 to S16 described in place
Indicates each operation step. Further, G1 to G5 indicate frame groups GOP1 to 5, that is, moving image data for normal reproduction, and I2 to I4 indicate I pictures I20 to I40, that is, moving image data for fast forward.

When fast forward playback is selected by the user during normal playback, the host CPU 2 of the terminal unit 1 sends a control signal for fast forward to the server unit 20 via the control signal communication unit 3 (S11), and the host Immediately after that, the CPU 2 issues a pause instruction to the decoding unit 6 to pause the display on the video display unit 8. At almost the same time, the data G2 in the image data storage unit 5 is discarded (S12). The shaded portion of G2 indicates the discarded data, and G2 adjacent to the shaded portion indicates the data immediately before being discarded.

Next, the server unit 20 receiving the control signal from the control signal communication unit 3 switches the transfer data from the GOP data to the fast-forwarding data and transfers it to the terminal unit 1. At this time, in the server unit 20, the read control unit 24 sets the fast-forward data in time series (oldest first), that is, with the I picture I2 corresponding to G2 as the head, and the system data processing unit 4 in the order of I3 and I4. Have transferred to.

The host CPU 2 confirms that the system data processing unit 4 has sent the fast-forwarding data, cancels the pause, and performs the same processing as the normal-playing the fast-forwarding data to display an image. It is displayed on the section 8 (S13).

To cancel the fast-forward reproduction, when the user selects normal reproduction, the host CPU 2 sends a fast-forward reproduction cancel signal to the server section 20 via the control signal communication section 3 (S14), and the host CPU 2 Then, the display is temporarily stopped by the decoding unit 6, and the data I4 in the image data storage unit 5 is discarded (S15).

Next, the server unit 20 changes the transfer data from the fast-forward data to G0P data comparable to the currently displayed frame, that is, G4 for the I picture I4, and transfers it to the terminal unit 1. Then, the host CPU 2 confirms that the data for normal reproduction has been sent by the system data processing unit 4, releases the pause, and then displays the video for normal reproduction again on the video display unit (S16). ). Then, the video for normal reproduction is displayed in the order of G5, ...

In this way, the fast forward is started with the I picture I2 corresponding to the temporarily stopped G2 as the head, and the normal reproduction is started with the G4 corresponding to the temporarily stopped I4 as the head, so that the normal reproduction is changed to the fast forward reproduction. It is possible to visually connect the fast connection and the fast-forward playback to the normal playback.

Next, the operation of the fast rewind reproduction display will be described. FIG. 5 is a schematic explanatory view showing the operation timing of the fast rewind reproduction display. The displays G, I, and
The meanings of S and the like are the same as those in FIG.

When the fast rewind reproduction is selected by the user during the normal reproduction, the host CPU 2 of the terminal unit 1 sends a control signal for fast rewind to the server unit 20 via the control signal communication unit 3 ( Immediately thereafter, the host CPU 2 issues a pause instruction to the decoding unit 6 to suspend the display on the video display unit 8 (S21). At almost the same time, the data G7 in the image data storage unit 5 is discarded (S22). G
The shaded area 7 indicates the discarded data, and G7 adjacent to the shaded area indicates the data immediately before being discarded.

Next, the server section 20 receiving the control signal from the control signal communication section 3 switches the transfer data from the GOP data to the fast rewind data and transfers the data to the terminal section 1. At this time, in the server unit 20, the read control unit 24 sets the data for fast rewind in reverse time series (new order), that is, with the I picture I6 corresponding to the GOP data G6 immediately preceding G7 as the head. , I5, I4 in this order to the system data processing unit 4.

Further, the host CPU 2 confirms that the data for fast rewind is sent by the system data processing unit 4, releases the pause, and performs the same processing as the normal reproduction of the data for fast rewind. And display it on the video display unit 8 (S2
3).

To cancel the fast rewind, when the user selects normal reproduction, the host CPU 2 sends a fast rewind cancellation signal to the server unit 20 via the control signal communication unit 3 (S24), and the host CPU 2 After that, the display is temporarily stopped by the decoding unit 6, and the data I4 in the image data storage unit 5 is discarded (S25).

Next, the server section 20 transfers the transfer data from the fast rewind data to the G immediately preceding the G7 discarded in S22.
The data is changed to OP data G6 and transferred to the terminal unit 1. Then, the host CPU 2 confirms that the data for normal reproduction has been sent by the system data processing unit 4, releases the pause, and then displays the video for normal reproduction again on the video display unit (S26). ). Then, after G6, G7 ...
The images for normal playback are displayed in this order.

As described above, the fast rewind is started from the I picture I6 corresponding to the G6 immediately before the temporarily stopped G7, and the fast rewind is switched to the normal reproduction by the G6 immediately before the start of the fast rewind. Therefore, the connection from the normal reproduction to the fast rewinding reproduction and the connection from the fast rewinding reproduction to the normal reproduction can be performed visually without a feeling of strangeness.

In the present embodiment, the number of GOP pictures is set as a set of 15. However, by reducing this number, the fast-forward or fast-rewind speed can be lowered, and conversely, the number of GOPs can be reduced. By increasing it, the fast forward or fast rewind speed can be increased.

[0044]

According to the present invention, moving image data for normal reproduction formed by a series of frame groups consisting of at least one independent frame and a fixed number of non-independent frames following the independent frame, and independent of the frame group. Since the fast-moving moving image data formed by arranging only the frames in time series, the storage means for storing both of these data, and the read control means for reading either one of the data from the storage means are provided. In the case of fast-forwarding, the fast-forwarding reproduction can be performed by reading out the moving image data for fast-forwarding from the storage means and processing the read-out data as it is in the device for normal reproduction. Further, it is possible to easily perform fast-forward reproduction at equal intervals.

Therefore, it is not necessary to perform decoding of extra data or frame selection processing according to the reproduction speed, so that the circuit scale can be reduced and the reproduced image can be sharpened.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of a moving image fast-forward reproducing apparatus according to the present invention.

FIG. 2 is a configuration diagram of an embodiment of a server unit of the fast-forward reproduction device.

FIG. 3 is a schematic explanatory view showing a data structure of moving image data of the fast-forward reproduction device.

FIG. 4 is a schematic explanatory view showing an operation timing of fast-forward reproduction display of the fast-forward reproducing apparatus.

FIG. 5 is a schematic explanatory diagram showing an operation timing of fast-rewind reproduction display of the fast-forward reproduction apparatus.

[Explanation of symbols]

 1 Terminal Unit 2 Host CPU 3 Control Signal Transmission Unit 4 System Data Processing Unit 6 Decoding Unit 7 NTSC Encoder 8 Video Display Unit 20 Multimedia Communication Server Unit 21 Normal Image Memory 22 Fast Forward Image Memory 23 Fast Rewind Image Memory 24 Readout Control Unit

Claims (4)

[Claims] 1. A fast-forwarding reproduction apparatus for a moving image, comprising an independent frame coded by an intra-frame coding method and a non-independent frame coded by an inter-frame coding method, and at least one independent frame. , And moving image data for normal reproduction formed by a series of frame groups consisting of a fixed number of non-independent frames and a moving image for fast forward formed by extracting only independent frames from the frame group and arranging them in time series Storage means for storing the data and the moving image data for the normal reproduction and the fast-forwarding;
A fast-forward reproducing apparatus for moving images, comprising: read-out control means for selectively reading out the moving-image data for the normal reproduction or the fast-forwarding from the storage means. 2. The fast-forward playback device for moving images further includes moving image data for fast rewinding, which is formed by extracting only independent frames from the frame group and arranging them in reverse time series, and the storage means stores the fast moving images. The read control means includes a function of storing moving image data for rewinding, and the read control means selectively reads out one of the moving image data for normal reproduction, fast forward, or fast rewind from the storage means. 2. The fast-forwarding reproduction apparatus for moving images according to claim 1, further comprising a function of: 3. The fast-forwarding reproduction apparatus for moving images according to claim 1, wherein the read control means has a function of reading out the moving image data in a frame arrangement order. 4. The fast-forwarding reproduction apparatus for moving images according to claim 1, further comprising image conversion means for converting the moving image data read out from said readout control means into an image and displaying it.