JP2001103488A - Dynamic image encoder and dynamic image encoding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To encode a designated frame as a head image of a GOP structure using a simple configuration. SOLUTION: A memory 13 stores in advance a time code of a frame, that is desirably used for a head frame of GOP in a bit stream received by a video encoder 12. Then in the case of encoding, the video encoder 12 compares the time code stored in the memory 13 with a time code attached to each of frames in the bit stream and encodes the bit stream, by using a frame whose time code matches with the stored time code as the head frame of the GOP, when the result of comparison indicates matching.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving picture coding apparatus and a moving picture coding apparatus for coding a moving picture signal composed of a plurality of frames, each frame having identification information for identifying its own frame added in a GOP structure. About the method of conversion.

[0002]

2. Description of the Related Art Recently, with the progress of digital technology, video compression technology by digitizing video signals has been actively developed. As this video compression technology, for example, MPEG
(Moving Picture Coding Experts Group) 2.

[0003] Broadcasting stations include, for example, HDTV (High Definition TV) studios and S
There is a DTV (Standard Definition TV) studio, an MPEG editing room, and the like. Here, in the MPEG editing room, MPEG
A video encoder for two is provided, and a bit stream to be broadcast is encoded into an encoded image signal of the MPEG2 system by a video encoder and broadcast. This type of video encoder encodes an input signal in a GOP structure.

[0004] This GOP structure is composed of an I picture in which one frame itself is directly coded by the intra-frame coding method, a P picture coded by using prediction from a past frame, and a past and future. B pictures encoded using predictions from both frames,
For example, in a repetition pattern of 15 frames composed of IBBPBBPBBPBBPBB, a G
An OP header is added.

[0005] In the case of an I picture, an encoded image signal encoded in such a GOP structure is decoded in an inner frame by information in the picture, but is decoded in a P picture or a B picture. In the case of such predictive coding, one frame is not correctly decoded because there is no information in the picture. Therefore, conventionally, it has been considered that an important frame is encoded with an I picture.

However, in the above-mentioned video encoder, since a bit stream is encoded in a predetermined GOP structure, there is a problem that a designated frame cannot be encoded into an I picture.

[0007]

As described above, in the conventional video encoder, since encoding is performed using a predetermined GOP structure, encoding is performed using a designated frame as the first frame of the GOP. There is a problem that can not be.

An object of the present invention is to provide a moving picture coding apparatus and a moving picture coding method capable of coding a designated frame as a first picture of a GOP structure with a simple configuration.

[0009]

SUMMARY OF THE INVENTION A moving picture coding apparatus according to the present invention comprises a plurality of frames, in which a moving picture signal in which identification information for identifying the own frame is added to each frame is subjected to intra-frame coding and frame coding. GO consisting of inter-coding
In a moving picture coding apparatus for coding in a P (group of picture) structure, a storage means for storing designation information inputted from the outside, and each frame of the designation information and the moving picture signal stored in the storage means And encoding control means for performing an encoding process by using a frame corresponding to the coincident identification information as a first frame of the GOP when the identification information is compared with the identification information added to the GOP. Things.

According to this configuration, of the input moving image signal, the identification information of the frame desired to be the first frame of the GOP is stored in advance, and the stored identification information and the encoding information in the moving image signal are encoded. When the identification information added to each frame is matched, encoding is started with the frame corresponding to the matched identification information as the first frame of the GOP. That is, when the designated frame is detected, the encoding process is reset, and the designated frame is used as the first picture of the GOP, and the encoding process using the normal GOP structure can be performed thereafter.

For this reason, at the time of encoding, a specified frame in a moving image signal can be encoded as the first picture of a GOP.

Further, the moving picture coding apparatus according to the present invention converts a moving picture signal comprising a plurality of frames, to each of which frames identification information for identifying the own frame is added, from intra-frame coding and inter-frame coding. In a moving picture coding apparatus for coding in a GOP (Group of Pictures) structure, an external control device connecting means for connecting an external control device and designation from an external control device connected by the external control device connecting means Encoding control for comparing the information with the identification information added to each frame of the moving image signal, and performing a coding process using the frame corresponding to the matched identification information as the top frame of the GOP when the comparison results in a match. Means.

According to this configuration, the same effect as described above can be obtained even when the designation information is input to the external control device.

Further, the moving picture coding method according to the present invention is characterized in that a moving picture signal consisting of a plurality of frames and having each frame added with identification information for identifying the own frame is subjected to intra-frame coding and inter-frame coding. In a moving picture coding method for coding in a GOP (group of picture) structure, a designated information input from the outside is stored, and the designated information and identification information added to each frame of the moving picture signal are stored. If the two frames are compared according to the comparison result, the frame corresponding to the matched identification information is referred to as the GO.
The encoding process is performed as the first frame of P.

Further, even when an external control device is connected, the specification information from the external control device is compared with the identification information added to each frame of the moving picture signal. The encoding process is performed by using a frame corresponding to the identified identification information as a top frame of the GOP.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIG. 1 is a block diagram showing a system to which a moving picture coding apparatus according to the present invention is applied.

In FIG. 1, a bit stream transmitted from a VTR (video tape recorder) 11 is supplied to a video encoder 12 according to the present invention. This bit stream is a moving image signal composed of a plurality of frames and having each frame added with a time code for identifying the own frame.

The video encoder 12 encodes the input bit stream in a GOP structure including three types of pictures, I, P, and B, and outputs the encoded bit stream as an MPEG2 stream.

The video encoder 12 according to the first embodiment is provided with a memory 13, and the memory 13 stores a time code of an externally designated frame. That is, the video encoder 12
The encoding process according to the time code stored in the memory 13 is executed.

Next, the operation in the above configuration will be described with reference to FIG.
This will be described with reference to FIG. FIG. 2 is a timing chart showing the structure of the bit stream input to the video encoder 12 and the structure of the MPEG2 stream encoded by the video encoder 12. FIG. 3 shows the control of the video encoder 12 at the time of encoding. It is a flowchart which shows a procedure.

That is, a bit stream composed of a plurality of frames as shown in FIG. Here, in the memory 13, for example, the time code of the fifth frame from the left in FIG. 2A is stored.

The video encoder 12 extracts a time code from each frame of the input bit stream (step 3a), and compares the extracted time code with the time code stored in the memory 13 (step 3).
b), it is determined whether they match (step 3c). Here, if they do not match (NO), the video encoder 12 performs an encoding process on the frame according to the existing GOP structure (step 3d). In step 3c, when the time code of the fifth frame in FIG. 2A matches the time code in the memory 13 (YES), the video encoder 12 sets the frame corresponding to the fifth frame in FIG. As shown in b), the encoding process is executed as a frame of the I picture of the GOP (step 3e). The processing of steps 3a to 3e as described above is executed for each frame.

As described above, according to the first embodiment, of the bit stream input to the video encoder 12, the time code of the frame desired to be the first frame of the GOP is stored in the memory 13 in advance, and Is performed, when the time code stored in the memory 13 matches the time code added to each frame in the bit stream in the video encoder 12,
The frame corresponding to the matched time code is GOP
, The encoding is started as the first frame. That is, when the designated frame is detected, the encoding process is reset, and the designated frame can be used as an I picture of the GOP, and the encoding process using the normal GOP structure can be performed thereafter.

Therefore, at the time of encoding, a specified frame in a bit stream can be encoded as an I picture of a GOP. Therefore, when the designated important frame is decoded, it can be surely decoded.

(Second Embodiment) In a second embodiment of the present invention, a time code of a frame designated to an external control device such as a personal computer is input instead of a memory.

FIG. 4 is a block diagram showing a system to which the moving picture coding apparatus according to the second embodiment of the present invention is applied. In FIG. 4, the same portions as those in FIG. 1 are denoted by the same reference numerals, and detailed description will be omitted.

In FIG. 4, an external control device 14 is connected to the video encoder 12. That is, the editor can use the external control device 14 to input the time code of the frame to be encoded with the I picture.

When performing encoding, the video encoder 12 compares the time code from the connected external control device 14 with the time code added to each frame of the bit stream. The frame corresponding to the matched time code
The encoding process is performed as an OP I picture.

In the second embodiment, the first embodiment
The same effect as that of the embodiment can be obtained. Further, if the external control device 14 is replaced with a remote control receiver, the frame can be specified by remote control, which is very convenient for the editor.

The present invention is not limited to the above embodiments. For example, in each of the above-described embodiments, the time code added to the frame is used as the frame identification means. However, other identification information that can identify the own frame may be used.

In addition, the configuration and type of the video encoder can be variously modified without departing from the scope of the present invention.

[0033]

As described in detail above, according to the present invention,
With a simple configuration, it is possible to provide a moving picture coding apparatus and a moving picture coding method capable of coding a designated frame as a first picture of a GOP structure.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a system to which a moving picture coding apparatus according to the present invention is applied.

FIG. 2 is a timing chart showing the structure of a bit stream input to the video encoder shown in FIG. 1 and the structure of an MPEG2 stream encoded by the video encoder.

FIG. 3 is a flowchart showing a control procedure when encoding is performed in the video encoder shown in FIG. 1;

FIG. 4 is a block diagram showing a system to which a moving picture coding apparatus according to a second embodiment of the present invention is applied;

[Explanation of symbols]

 11: VTR, 12: video encoder, 13: memory, 14: external control device.

Claims (4)

[Claims] 1. A moving image signal comprising a plurality of frames, to which identification information for identifying the own frame is added to each frame, is represented by a G signal comprising intra-frame encoding and inter-frame encoding.
In a moving picture coding apparatus for coding in an OP (Group of Picture) structure, a storage means for storing designation information input from the outside, and each of the designation information stored in the storage means and the moving picture signal Encoding control means for comparing the identification information added to the frame and, when the result of the comparison indicates a match, performing an encoding process with a frame corresponding to the matched identification information as a head frame of the GOP; A moving picture coding apparatus characterized in that: 2. A moving image signal comprising a plurality of frames, to which identification information for identifying the own frame is added to each frame, is converted into a G signal comprising intra-frame encoding and inter-frame encoding.
In a moving picture coding apparatus for coding in an OP (Group of Picture) structure, an external control device connecting means for connecting an external control device, and designation information from the external control device connected by the external control device connecting means Is compared with the identification information added to each frame of the moving image signal, and when they match according to the comparison result, the frame corresponding to the matching identification information is compared with the GO.
A moving picture coding apparatus comprising: coding control means for performing a coding process as a first frame of P. 3. A video signal composed of a plurality of frames and having each frame added with identification information for identifying its own frame is represented by a G signal comprising intra-frame encoding and inter-frame encoding.
In a moving picture coding method for coding in an OP (Group of Picture) structure, specified information input from the outside is stored, and the specified information and identification information added to each frame of the moving picture signal are stored. A moving picture coding method, comprising: performing a comparing process; and, when a match is obtained based on the comparison result, performing a coding process using a frame corresponding to the matching identification information as a first frame of the GOP. 4. A video signal comprising a plurality of frames, to each frame to which identification information for identifying its own frame has been added, is provided with a G signal comprising intra-frame encoding and inter-frame encoding.
In a moving picture coding method for coding in an OP (group of picture) structure, an external control device is connected, designation information from the connected external control device and identification added to each frame of the moving picture signal. Information, and when a match is found based on the comparison result, a frame corresponding to the matched identification information is stored in the GOP.
A moving image encoding method, wherein an encoding process is performed as a first frame of the moving image.