JP2003153260A - Moving picture file generating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a moving picture file generating apparatus that can quickly terminate file creation when an end command is issued and exclude unnecessary information to the file. SOLUTION: One-frame buffers 5a, 5b of a multiplexing/file generating device 5 store a video bit stream and an audio bit stream encoded by a video encoder 1 and an audio encoder 2, respectively, by one frame or for a period equivalent thereto. When a file end command (c) is received via a terminal 7, a multiplexing/file generating unit 5c reads data from the one-frame buffers 5a, 5b a sequence end code (f) is attached to the end of the video bit stream from the one-frame buffer 5a, the result is multiplexed and the file is outputted. As a result, when the file end command (c) is received, the file is immediately generated and the operation is early terminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving picture file generating apparatus, and more particularly to a moving picture file generating apparatus for storing a compression-coded moving picture in a file as a sample for each frame.

[0002]

2. Description of the Related Art Conventionally, a moving image which is compression-encoded at a low encoding frame rate of, for example, 0.5 frame per second (that is, 1 frame per 2 seconds) and which is stored as a sample in a file A file generation device has been proposed. A conventional moving image file generation device of this type will be described with reference to FIGS.

FIG. 5 is a block diagram showing a configuration of an MP4 file generating device which is a standard file format of MPEG-4, for example, and FIG. 6 is a block diagram showing a specific configuration of the video encoder 31 of FIG. .

As shown in FIG. 5, the MP4 file generating apparatus includes a video encoder 31 for encoding the input image signal a at a predetermined encoding rate and an audio encoder 32 for encoding the input audio signal b. A buffer 33 for temporarily storing compression-encoded image data, a buffer 34 for temporarily storing encoded audio data, and multiplexing the encoded image data, a video bit stream that is audio data, and an audio bit stream. And a file generation unit 35 for generating a file by a terminal. When the file generation is ended, the end command c is input from the terminal 40.

As shown in FIG. 6, the video encoder 31 includes an encoder 41 and an end code generator 4
2, an adder 43 and an AND gate 44. The operation of the video encoder 31 will be described with reference to the flowchart of FIG.

In step S11, it is judged whether or not the time for video coding has come. If this judgment is affirmative, the coding section 41 starts coding. Step S
In 12, the bit stream g from the encoding unit 41 is output to the buffer 33 and accumulated. In step S13, it is determined whether or not the encoding of one frame is completed. When the determination is negative, the process returns to step S12, and the encoding and the output of the bit stream g to the buffer 33 are continued.

When it is determined in step S13 that the encoding of one frame is completed, the process proceeds to step S14, and it is determined whether or not the end command c from the terminal 40 is issued. When the determination is negative, the process proceeds to step S15, and the frame coding completion message d is output. Then, the process returns to step S11, and when, for example, 2 seconds elapse, the determination in step S11 becomes affirmative and the process proceeds to step S12. Hereinafter, the above operation is repeated.

Next, when the determination in step S14 becomes affirmative, the process proceeds to step S16, in which the end code generator 42 generates a sequence end code f, and the sequence end code f is added to the end of the bit stream output e. It Next, in step S17, the frame encoding completion message d is output, and in step S18, the encoding stop signal h is output.

When the video encoder 31 operates as described above, the multiplexing / file generating unit 35 in FIG. 5 receives the frame coding completion signal d, and then the buffers 33, 3
After extracting the bit stream for 4 frames and the audio bit stream for the time corresponding to 1 frame of the image signal from 4 and multiplexing them in a predetermined format,
Output a file. In addition, the encoding stop signal h output in step S18 is the audio encoder 32.
Is input to the multiplexing / file generation unit 35, and these operations are stopped.

[0010]

Since the sequence end code f of the video bit stream is defined by the video coding standard such as MPEG-4 Visual,
As described above, it is natural for the video encoder 31 to generate the end code f. However, considering output of a video bitstream in a file format such as MP4, which is an international standard format defined to generate a file in units of frames, the following problems occur.

That is, for the last frame of the sequence, after the end command c is issued, the end of encoding of the next frame is waited for, and the bit stream of the video frame and the sequence end code f are combined to obtain frame information g. You will have to create a file as.

As a result, when the coding frame rate is low, for example, 0.5 frame per second, as shown in FIG. 8, it is not longer than 2 seconds at the worst after the end command c is issued. The problem arises that the sequence cannot be terminated. Here, the upper part of FIG. 8 shows the video bit streams g1 and g output from the video coder 31.
2, g3, ..., gn, g (n + 1), and the lower row is
The data multiplexed by the multiplexing / file generation unit 35 is shown. As is clear from the figure, when the end command c is issued immediately after the video bitstream gn, the end code f is attached to the video bitstream g (n + 1), and the sequence is ended. It takes about 2 seconds from the issue to the end of file generation.

After issuing the end command c, at least one frame of video bit stream g (n +
Since the audio bit stream corresponding to 1) and the period is output to the file, the unnecessary information is output to the file, resulting in a problem of poor efficiency and accuracy.

An object of the present invention is to solve the above-mentioned problems of the prior art, to terminate the file generation early when an end command is issued, and to prevent unnecessary information from being included in the file. Providing a generator.

[0015]

In order to achieve the above-mentioned object, the present invention has completed compression encoding in a moving image file generation apparatus for storing a compression encoded moving image in a file for each frame. Storage means for storing the video bitstream, and file generation means for extracting the video bitstream from the storage means and generating a file
Sequence end code generation means for generating a sequence end code when receiving an end command for instructing the end of file generation, and transmitting the sequence end code to the file generation means, wherein the file generation means receives the sequence end code, The first feature is that the video bitstream is extracted from the storage means and the sequence end code is added to the video bitstream.

A second feature of the present invention is that sequence end code generation means for generating a sequence end code in response to an end command for instructing the end of file generation is provided independently of the video encoder. is there.

According to these characteristics, when the termination command is issued, the file generation can be terminated early, and unnecessary information can be prevented from being included in the file.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of one embodiment of the present invention, and FIG. 2 is a block diagram showing a configuration of a specific example of the video encoder of FIG.

As shown in FIG. 1, the moving image file generating apparatus according to the present embodiment has a video encoder 1 for compressing and encoding an input image signal, an audio encoder 2 for encoding an input audio signal b, and the video. A buffer 3 that temporarily stores the video bitstream output e from the encoder 1, a buffer 4 that temporarily stores the audio bitstream output from the audio encoder 2, and a sequence end code f from the video sequence end code generation unit 6. Is added to the end of the bitstream to perform multiplexing, and then a multiplexing / file generation unit 5 for generating a file and an end command c input via the terminal 7.
The video sequence end code generator 6 generates a sequence end code f by using as a trigger.
In addition, the multiplexing / file generation unit 5 includes a 1-frame buffer 5 connected to each of the buffers 3 and 4.
a, 5b, and a multiplexing / file generation unit 5c.

The video encoder 1 is composed of an encoder 11 as shown in FIG. The operation of the encoding unit 11 will be described with reference to the flowchart of FIG. In step S1, it is determined whether or not the end command c has been issued. If the determination is negative, the process proceeds to step S2 to determine whether or not it is time to code. When this determination is affirmative, the process proceeds to step S3, the input image signal a is encoded, and the video bit stream e is output to the buffer 3. In step S4,
It is judged whether or not one frame has been encoded,
When this determination is negative, the process returns to step S3 to continue the encoding and the output to the buffer 3. When the encoding of one frame is completed and the determination in step S4 is affirmative, the process proceeds to step S5 and the frame encoding completion message d
Is output. The frame coding completion message d is input to the multiplexing / file generation unit 5c. Less than,
The above operation is repeated.

After that, when the end command c is issued,
The determination in step S1 becomes affirmative, and the operation of the video encoder 1 ends immediately.

Next, the operation of the moving image file generating apparatus will be described with reference to FIG. Normally, when the multiplexing / file generation unit 5c receives the frame encoding completion message d from the video encoder 1, the multiplexing / file generation unit 5c outputs the 1-frame buffer
Video frame of 1 frame from a, 5b,
The audio bitstream is extracted, multiplexed in a predetermined format, and then output as a file.

When the end command c is input via the terminal 7, the video encoder 1 immediately stops its operation, and similarly, the audio encoder 2 also immediately stops its operation.
The video sequence end code generator 6 outputs the sequence end code f by using the end command c as a trigger.

The 1-frame buffers 5a and 5b store a 1-frame bit stream already encoded and an audio bit stream corresponding to the video bit stream period of the 1-frame. Therefore,
When the end command c is input, the multiplexing / file generation unit 5c extracts one frame of the video bitstream from the one frame buffer 5a and adds the sequence end code f (or the video end code) to the end of them. A file is generated by multiplexing with the audio bitstream extracted from the 1-frame buffer 5b, and the file is output. The sequence end code f is, for example, ISO / IEC 14496-2 (MP
In the case of EG-4Visual), the hexadecimal number (000001)
It becomes 4 bytes of B1).

FIG. 4 shows a timing chart of multiplexing and file generation of this embodiment. Video bitstreams e1, e2 encoded by the video encoder 1
e3, ... En are multiplexed with the audio bit stream with a delay of one cycle (for example, 2 seconds) and output to a file. When the end command c is issued, the multiplexing / file generation unit 5c extracts the video bitstream en from the 1-frame buffer 5b at the time of receiving the end command c and adds the sequence end code f.

Therefore, according to this embodiment, the multiplexing of the video bit stream and the audio bit stream and the file generating operation are completed immediately after the termination command c is issued, and the moving image file generation can be terminated. Like

In the above embodiment, the example of multiplexing and file generation is described, but the present invention is not limited to this, and can be applied to a device that simply generates a file of a video bitstream. The configuration of the above-described embodiment is merely an example, and it is obvious that the present invention includes other embodiments without departing from the spirit of the present invention.

[0028]

As is apparent from the above description, according to the inventions of claims 1 to 4, when the termination command is issued, the file generation can be terminated early and unnecessary information is transmitted. It can be excluded from the file.

As a result, the efficiency of moving image file generation is improved, and the accuracy of file contents is improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of the video encoder in FIG.

FIG. 3 is a flowchart illustrating an operation of the video encoder.

FIG. 4 is a timing chart showing an essential part of the operation of the present embodiment.

FIG. 5 is a block diagram showing a configuration of a conventional device.

6 is a block diagram illustrating a configuration of the video encoder of FIG.

FIG. 7 is a flowchart for explaining the operation of the video encoder of FIG.

FIG. 8 is a timing chart showing an essential part of the operation of the conventional device.

[Explanation of symbols]

1 ... video encoder, 2 ... audio encoder,
3, 4 ... Buffer, 5 ... Multiplexing / file generation device,
5a, 5b ... 1 frame buffer, 5c ... Multiplexing / file generating unit, 6 ... Video sequence end code generating unit, 11 ... Encoding unit.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koichi Takagi             2-15-1 Ohara, Kamifukuoka City, Saitama Stock             Company CAD Research Institute (72) Inventor Shigeyuki Sazawa             2-15-1 Ohara, Kamifukuoka City, Saitama Stock             Company CAD Research Institute (72) Inventor Yasuhiro Takishima             2-15-1 Ohara, Kamifukuoka City, Saitama Stock             Company CAD Research Institute (72) Inventor Masahiro Wada             2-15-1 Ohara, Kamifukuoka City, Saitama Stock             Company CAD Research Institute F-term (reference) 5C053 FA07 FA14 GA10 GB06 GB37                       JA07 JA21 KA01 LA11                 5C059 KK15 KK39 MA00 PP01 PP04                       RB02 RB09 RB14 RC24 RC32                       RC33 SS11 SS26 UA02 UA32

Claims (4)

[Claims] 1. A moving image file generation apparatus for storing a compressed and encoded moving image in a file frame by frame, and a storage unit for storing a compressed and encoded video bit stream, and a video bit stream from the storage unit. And a sequence end code generating means for generating a sequence end code when receiving an end command for instructing the end of the file generation and transmitting the sequence end code to the file generating means. The video image file generation device, wherein when receiving the sequence end code, extracts the video bit stream from the storage means and adds the sequence end code to the video bit stream. 2. The apparatus further comprises storage means for storing the encoded audio bitstream, wherein the file generation means extracts the video bitstream and the audio bitstream from the storage means when receiving the sequence end code, 2. The moving picture file generation device according to claim 1, wherein the sequence end code is added to the video bit stream and multiplexed. 3. The moving image file generation device according to claim 1, wherein the storage unit is a one-frame buffer. 4. A sequence end for generating a sequence end code in response to an end command instructing the end of file generation in a moving image file generation device for storing a moving image compressed and encoded by a video encoder in a file for each frame. A moving image file generating apparatus, wherein a code generating means is provided independently of the video encoder.