JPH07162851A - Special reproducing method - Google Patents

Abstract

PURPOSE:To enable much smoother high-speed search by dividing a block coded by an in-frame coding means into slices constituted by laterally arranging blocks in one line, and decoding the prescribed number of slices while shifting them for the prescribed number of slices between frames. CONSTITUTION:Each frame is divided into the slices of six layers from slice 1 to a slice 6. Then, the slice 1 is decoded and reproduced at the 0th frame, the slice 2 is decoded and reproduced at the 6th frame, and the slice 3 is decoded and reproduced at the 12th frame. Thus, the slice shifted from the slice processed at the preceding six frames just for one slice is decoded and reproduced for each frame. When the slice to be processed reaches the slice 6 at the picture edge like the 30th frame, the processing of the next 36th frame is performed by returning to the slice 0. Thus, a decoding processing amount is reduced into 1/6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for decoding an encoded moving picture signal, and more particularly to a special reproduction method in a moving picture decoding and reproducing system for a data storage medium such as an optical disk. Is.

[0002]

2. Description of the Related Art As a method of coding a moving image signal, there are intraframe coding utilizing spatial correlation and interframe coding utilizing temporal correlation. The latter interframe coding that uses correlation in the time direction can increase the compression rate compared to the former intraframe coding, but when an error occurs, this error propagates in the time direction. Intra-frame coding is performed to refresh at regular intervals. In this method, when the cycle is n frames, n-times speed reproduction can be realized by decoding and reproducing only the intra-coded frames.

FIG. 4A shows a basic pattern of compression coding in which the above-described intraframe coding and interframe coding are mixed. In this example, the intra-frame coding process is periodically performed every 6 frames, and the inter-frame coding process is performed during that period. That is, the cycle n
Is set to 6. At this time, as shown in FIG. 4B, 6-times speed reproduction can be realized by picking up only the frames subjected to the inter-frame coding processing and decoding and reproducing them.

Now, let us consider a case where high-speed reproduction of n times or more speed is performed. In this case, as shown in FIG. 4C, n × (p + 1) -times speed reproduction can be realized by thinning out a predetermined number of p frames and decoding and reproducing each frame. In FIG. 4C, p = 2
18 times speed reproduction is realized.

[0005]

However, in the case of performing high-speed reproduction of n times or more speed, when the predetermined number of frames of the intra-coded frames are thinned and decoded and reproduced, the information of the thinned frames is lost. Since the distance between the frames in the time axis direction becomes large, there is a problem that the motion of the reproduced image is not smooth and it is difficult to identify the flow of the image.

In view of the above problems, it is an object of the present invention to realize a special reproduction method in which a reproduced image has a smooth motion.

[0007]

In order to achieve the above object, the special reproduction method of the present invention digitizes a moving image signal and uses intra-frame coding and inter-frame coding to configure a plurality of pixels. In the decoding of a moving image signal recorded and accumulated by a signal processing method that performs encoding in block units, a frame encoded by intraframe encoding is sliced by arranging the blocks in one row in the horizontal direction. It is divided into a plurality of slices, and a predetermined number of the slices are decoded and reproduced by shifting by a predetermined number of slices between frames encoded by intra-frame coding, or a limited number of slices within one frame. High-speed reproduction is realized by decoding and reproducing only one of them, or by reproducing by a combination of these two methods.

[0008]

According to the present invention, by decoding and reproducing a part of the frame by the above method, the processing coding amount is reduced without thinning out the frame, so that a smoother and faster image reproduction is realized. It will be.

[0009]

EXAMPLE An example of the special reproduction method of the present invention will be described below.
A description will be given with reference to the drawings.

FIG. 1 is an explanatory diagram of a trick-play method according to the first embodiment of the present invention. In the figure, (a) shows a basic pattern of compression coding in which intra-frame coding and inter-frame coding are mixed, and in this example, intra-frame coding is performed during inter-frame coding at a cycle of 6 frames. This is an example of conversion. FIG. 1C is a diagram showing a special reproduction method according to the first embodiment of the present invention. FIG. 1B shows a case where only the frame subjected to the intra-frame encoding processing is picked up and decoded and reproduced, whereby 6 × speed reproduction is realized.

As shown in FIG. 1C, each frame is first divided into 6 layers of slices. These slices will be referred to as slice 1, slice 2, ..., Slice 6 in order from the top.

Then, slice 1 is decoded and reproduced in the 0th frame, and slice 2 is reproduced in the 6th frame.
Is decoded and reproduced, and slice 3 is reproduced in the 12th frame.
6 for each frame, such as decoding and reproducing
One slice at a position shifted by one slice from the slice processed in the frame before the frame is decoded and reproduced. Third
When the slice to be processed reaches the slice 6 at the end of the screen, like the 0th frame, the processing of the next 36th frame is performed by returning to the slice 0.

By doing so, the amount of decoding processing in each frame becomes 1/6, and the processing time is as shown in FIG.
Compared to the case of (b), it is 1/6, which is substantially the same as in FIG.
It is possible to realize 6 times as fast as (b), that is, 36 times speed reproduction. Further, if special reproduction as in this embodiment is performed, 1
The frame is divided into 6 slices, and adjacent slices having high correlation are combined for decoding decoding every ⅙ frame, so that the motion of the reproduced image can be made smooth. it can.

In this embodiment, the case where one frame is divided into 6 layers and one slice is decoded and reproduced for each frame has been described. However, the number of slices to be divided and decoding and reproduction for each frame are described. The same effect can be obtained even if the number of slices to be set is set to an arbitrary value. That is, when one frame is divided into p-layer slices and q slices are decoded and reproduced for each frame, p of FIG.
High-speed reproduction of / q times can be realized. However, here p> q.

An embodiment of the special reproduction method of the present invention will be described below with reference to the drawings. FIG. 2 shows the second aspect of the present invention.
6 is an explanatory diagram of a trick-play method in the embodiment of FIG. In the figure, (a) shows a basic pattern of compression coding in which intra-frame coding and inter-frame coding are mixed.
In this example, as in the first embodiment, the intra-frame coding is performed during the inter-frame coding at a cycle of 6 frames. FIG. 2C is a diagram showing a special reproduction method according to the second embodiment of the present invention. FIG. 2B shows a case where only the frame subjected to the intra-frame coding process is picked up and decoded and reproduced, whereby 6 × speed reproduction is realized.

As shown in FIG. 2C, each frame is first divided into 6 layers of slices. These slices will be referred to as slice 1, slice 2, ..., Slice 6 in order from the top. Then, in each frame, the processing of slice 1 and slice 6 is not performed, and only the remaining slices 2 to 5 are decoded and reproduced.

By doing so, the decoding processing amount in each frame becomes 4/6, and the processing time is as shown in FIG.
Compared with the case of (b), it is 4/6, which is substantially the same as in FIG.
It is possible to realize 6/4 times as fast as (b), that is, 9 times speed reproduction. Further, since decoding and reproduction are performed every 6 frames using all slices from slice 2 to slice 5,
It is possible to make the movement of the reproduced image smooth.

In this embodiment, one frame is divided into slices of 6 layers and four slices limited to each frame are decoded and reproduced. However, one frame is divided into an arbitrary number of slices. The same effect can be obtained even when division is performed and decoding reproduction is limited to an arbitrary number of slices at arbitrary locations. That is, when one frame is divided into p-layer slices and r slices limited to each frame are decoded and reproduced, high-speed reproduction of p / r times that in FIG. 2B can be realized. However, here p> r.

An embodiment of the special reproduction method of the present invention will be described below with reference to the drawings. FIG. 3 shows the third aspect of the present invention.
6 is an explanatory diagram of a trick-play method in the embodiment of FIG. In the figure, (a) shows a basic pattern of compression coding in which intra-frame coding and inter-frame coding are mixed.
In this example, similarly to the first and second embodiments, the intra-frame coding is performed during the inter-frame coding at a cycle of 6 frames. FIG. 3C is a diagram showing a trick-play method according to the third embodiment of the present invention. FIG. 3B shows a case where only the frame subjected to the intra-frame encoding processing is picked up and decoded and reproduced, and thereby 6 × speed reproduction is realized.

As shown in FIG. 3C, each frame is first divided into 6 layers of slices. These slices will be referred to as slice 1, slice 2, ..., Slice 6 in order from the top.

Then, in each frame, the processing of slice 1 and slice 6 is not performed, and only the remaining slices 2 to 5 are decoded and reproduced. Here, the slice 2 is decoded and reproduced in the 0th frame, the slice 3 is decoded and reproduced in the 6th frame, and the slice 4 is decoded and reproduced in the 12th frame. One slice at a position shifted by one slice from the slice processed in the frame 6 frames before is decoded and reproduced. When the slice to be processed reaches slice 5, which is the last slice of the limited slices, as in the 18th frame, the processing in the next 24th frame is performed by returning to slice 2.

By doing so, the total processing amount becomes 1/6 of that in the case of FIG. 3 (b), and the processing time is 1/6, which is substantially 6 times that of FIG. 3 (b). That is, it is possible to realize 36 × speed reproduction. Further, if special reproduction as in the present embodiment is performed, one frame is divided into 6 slices, and adjacent slices 2 to 5, which are highly correlated with each other, are combined for each ⅙ frame, and decoding reproduction is performed. Therefore, the motion of the reproduced image can be made smooth.

In this embodiment, the case where one frame is divided into six layers and four slices limited to each frame are decoded and reproduced for each frame is described. The same effect can be obtained even when it is divided into an arbitrary number of slices and is limited to an arbitrary number of slices at arbitrary places and decoding and reproduction of an arbitrary number of slices are performed for each frame. That is, when one frame is divided into slices of p layers and q slices limited to each frame are decoded and reproduced for r slices for each frame, p × r / q times in FIG. High speed reproduction can be realized. However, here, p>q> r.

Further, in the present embodiment, high-speed reproduction at the same speed as in the first embodiment is realized, but the decoding range is limited, and slices at the same slice position in one image. Since the time distance between them is shortened, smoother special playback can be realized.

[0025]

As described above, according to the present invention, the moving picture signal is digitized, and the intra-frame and inter-frame coding means are used to perform coding in block units composed of a plurality of pixels. In decoding the recorded and accumulated moving image signal, the frame coded by the intraframe coding means is divided into slices formed by arranging the blocks in one horizontal row, and a predetermined number of the slices are divided between the frames. By decoding with a predetermined number of slices and reproducing, or decoding and reproducing only a limited slice within one frame, or by using both methods, the processing code amount can be reduced without skipping frames. Since the number is reduced, a smoother and faster search can be realized.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a trick-play method according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a trick-play method according to the second embodiment of the present invention.

FIG. 3 is an explanatory diagram of a trick-play method according to a third embodiment of the present invention.

FIG. 4 is an explanatory diagram of a conventional trick play method.

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Claims (3)

[Claims] 1. A moving image signal recorded and accumulated by a signal processing method in which a moving image signal is digitized, and is encoded in a block unit composed of a plurality of pixels by using intra-frame encoding and inter-frame encoding. In decoding, a frame coded by intraframe coding is divided into a plurality of slices by slices formed by arranging the blocks in one row in the horizontal direction, and a predetermined number of the slices are coded by intraframe coding. A special reproduction method characterized in that high-speed reproduction is realized by shifting a predetermined number of slices between encoded frames and decoding and reproducing. 2. A moving image signal recorded and accumulated by a signal processing method in which a moving image signal is digitized, and coding is performed in a block unit composed of a plurality of pixels by using intra-frame coding and inter-frame coding. In decoding, a frame encoded by intraframe coding is divided into a plurality of slices by slices formed by arranging the blocks in one column in the horizontal direction, and only a predetermined number of slices in one frame are divided. A special reproduction method characterized by realizing high-speed reproduction by decoding and reproducing. 3. A moving image signal recorded and accumulated by a signal processing method in which a moving image signal is digitized, and coding is performed in block units composed of a plurality of pixels by using intra-frame coding and inter-frame coding. In decoding, a frame coded by intraframe coding is divided into a plurality of slices by slices formed by arranging the blocks in one row in the horizontal direction, and a predetermined number of slices in one frame are divided into a plurality of slices. A special reproduction method which realizes high-speed reproduction by shifting at least one slice among the frames encoded by intra-frame encoding by a predetermined number of slices and decoding and reproducing.