KR100658866B1 - Synchronization apparatus and method for video and audio data - Google Patents

Abstract

In the camera-phone recording stream, the audio data is input at the same time interval, in particular, by using a timer when recording a moving image, so that audio data that is first received after a recording restart, The present invention provides an apparatus and method for synchronizing audio and video data that improves the quality of a recorded image by not only including a synchronization point and not including it in a moving picture recording file.

The method of synchronizing video and audio data according to the present invention comprises the steps of: operating a timer by recognizing a first audio data signal received as a recording start signal when a recording is restarted after a recording pause; Discarding the first audio data signal after activating the timer; Comparing a time at which a video data signal incoming as an audio data signal and a video data signal preceding a recording pause command are input at the time of restarting the video recording; If the video data signal received as the audio data signal at the time of restarting the recording is smaller than the time at which the previous video data signal was received, setting the elapsed time to 0; And a step of performing recording in accordance with the timer being operated.

Video data synchronization, video codec, audio codec, elapsed time, timer, recording pause, resume recording

Description

Technical Field [0001] The present invention relates to a synchronization apparatus and method for video and audio data,

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic block diagram of a conventional portable terminal, and is a schematic block diagram for synchronization between chips in a recording mode. FIG.

2 is a configuration diagram showing a video and audio data synchronizing apparatus according to an embodiment of the present invention;

FIG. 3 illustrates a method of synchronizing audio and video data according to an embodiment of the present invention. FIG. 3 illustrates a method of synchronizing audio and video data according to an embodiment of the present invention. A comparison of video / audio data streams when restarted.

4 is a flow chart illustrating a video and audio synchronization method in accordance with the present invention.

Description of the Related Art

200: high frequency unit 202: modem chip (MSM) 204: audio processing unit 206: audio codec 208: timer 210: elapsed time calculating unit

212: speaker 214: microphone 216: key input unit

218: Video codec 220: DSP chip 222:

224:

The present invention relates to an apparatus and method for synchronizing video and audio data.

The video and audio data synchronizing apparatus and method can be applied to all areas where a video recording function such as a portable terminal or a camcorder is provided, but a portable terminal will be described below as an example.

Recently, portable phones are equipped with a high-definition digital camera and a camera phone designed to take a picture has been introduced and used. In such a portable terminal, the camera is divided into an external type and an internal type. The external type is a method of purchasing a separately purchased miniature digital camera and attaching it to the main body of the mobile phone. The built-in type is a method in which a small-

Such handheld terminals have various types and performances such as a camera phone capable of taking a simple picture, a camera phone capable of shooting a video of 30 minutes, a camera phone having a 260,000 color liquid crystal screen and a digital zoom function.

The portable terminal can photograph a video screen and display it as a moving picture and a still picture, and can also transmit the photographed video screen to the base station.

When attempting to perform the recording function or the camcorder function in the portable terminal, the time synchronization between the video data and the audio data must be performed.

FIG. 1 is a schematic block diagram of a conventional portable terminal, and is a schematic block diagram for synchronizing chips in a recording mode.

Referring to FIG. 1, a portable terminal includes a modem chip 100 and a DSP chip 102. The modem chip 1 controls various kinds of operation control related to the call and the overall operation of the system, and controls the DSP chip 102 by sensing a user's key input.

Here, the modem chip 100 may be implemented as an MSM (Mobile Station Modulator and Demodulator) chip, for example.

A DSP (Digital Signal Processor) chip 102 is a digital signal processor, and is controlled by the modem chip 100.

In the recording mode of the portable terminal, the timer 104 is used only in one of the two chips in the portable terminal using the dual chips 100 and 102, and the remaining chips receive time from the chip using the timer Thereby performing synchronization between the chips.

The modem chip 100 encodes an input audio signal, and the DSP chip 102 encodes a video signal captured by the camera. At this time, in order to synchronize the two chips, the modem chip 100 encodes the audio data from the time information of the clock generated by the timer 104, and transmits the audio data and the audio time increment at this time to the DSP chip 102 . Here, the audio time increment is a time for reproducing the audio data during the obtained audio time increment.

The DSP chip 102 receives the audio data and audio elapsed time, stores the audio data and audio elapsed time in a memory unit (not shown), and calculates a video elapsed time using the audio elapsed time. Here, the video elapsed time is a time value stored for reproduction of the video data.

The video elapsed time is obtained by subtracting the sum from the total time from the current audio elapsed time to the previous audio time. Therefore, the DSP chip 102 stores audio data and audio elapsed time, video data, and video elapsed time in a memory.

If the conventional video and audio data synchronization method operates as described above, the processor can not perform encoding at an appropriate time, and the video data signal is lost, thereby causing time synchronization to be lost.

In addition, if the pause / resume operation is repeated a number of times, the recorded audio data signal intervals may not be the same, the connection of video or audio may be unnatural, noise may occur, and the MP4 file format The size of the video file increases.

The present invention allows audio data to be input at the same time intervals by using an internal timer at the time of moving picture recording so that audio data that comes in first after recording is restarted after a pause in recording is regarded as a synchronization point of video and audio, The present invention provides an apparatus and method for synchronizing audio and video data to improve the quality of a recorded image.

The apparatus for synchronizing audio and video data according to the present invention performs overall control and call control of the system in a device for restarting recording after a recording pause, and when a first audio signal is received at the restart of the recording, A modem chip (MSM) for discarding the first audio data; A DSP chip connected to the modem chip for controlling storage of audio data and audio elapsed time after the first audio data; A camera unit connected to the DSP chip for capturing video data in a recording mode and transmitting a predetermined number of frames per second to the DSP chip; A memory unit connected to the DSP chip to store audio data and audio elapsed time transmitted from the modem chip and store the elapsed time as video elapsed time each time video data is input; Wherein the modem chip includes an elapsed time calculator for comparing the time at which the incoming video data such as audio data and the video signal prior to the recording pause command are received at the time of restarting the recording.

The method of synchronizing audio and video data according to the present invention comprises the steps of: operating a timer by recognizing a first audio data signal received as a recording start signal when recording is restarted after a recording pause; Discarding the first audio data signal after activating the timer; Comparing a time at which a video data signal incoming as an audio data signal and a video data signal preceding a recording pause command are input at the time of restarting the video recording; If the video data signal received as the audio data signal at the time of restarting the recording is smaller than the time at which the previous video data signal was received, setting the elapsed time to 0; And performing a recording according to the timer to be operated.

Generally, the audio data signals are input at the same time interval and pass through the audio codec. The audio signal compression method that is often used for video recording in portable terminals is AMR, QCELP, EVRC for low sound quality, and AAC for high sound quality.

Video data signals are also input at the same time intervals and pass through a video codec, using compression methods such as MPEG-4, H.263, and H.264. Most of the compressed data by the above compression method is stored in a file together with time information according to the MP4 file format.

Accordingly, in the present invention, synchronizing the temporal synchronization means that the input audio data signal and the video data signal are concatenated on the same time axis, and the respective video data signals are grouped based on the input time of the audio data signal Focus.

In order to synchronize the video data signal with the audio data signal, it is necessary to ensure that all audio data signals are input at the same time intervals. To do so, the elapsed time is corrected each time the audio data signal is input, Start internal timer to increase.

In addition, the audio compression data transmitted through the audio codec is stored together with the input time of the audio signal, and the current elapsed time is stored as the video elapsed time each time the video signal is input.

Likewise, video compression data from the video codec is stored in a file together with the stored video elapsed time.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram illustrating a video and audio data synchronizing apparatus according to an embodiment of the present invention.

Referring to FIG. 2, the video and audio data synchronizing apparatus includes a high frequency unit 200 for wireless communication, a modem chip (MSM) 202 for controlling the call control and the overall operation of the system, And an audio processing unit (204).

The modem chip 202 includes a data codec for processing packet data and the like and an audio codec 206 for processing audio signals such as voice.

In addition, the modem chip 202 includes a timer 208 for correcting the elapsed time and increasing the elapsed time each time an audio data signal is input, a timer 208 for, when a first audio signal arrives at the restart of recording after a recording pause, And an elapsed time calculator 210 for comparing the time of the input video signal and the video signal preceding the recording pause command to each other.

The video and audio data synchronizing apparatus includes a speaker 212 and a microphone 214 for inputting and outputting audio signals, a key input unit 216 having various kinds of key signals for talking and recording, And a DSP chip 220 that processes an incoming video signal and has a video CODEC 218.

The video and audio data synchronizing apparatus includes a camera unit 222 for capturing an external image and transmitting the captured image to the DSP chip 220, a liquid crystal display (LCD) unit 224 for displaying information, And a memory unit 226 for storing data.

FIG. 3 illustrates a method of synchronizing audio and video data according to an embodiment of the present invention. FIG. 3 illustrates a method of synchronizing audio and video data according to an embodiment of the present invention. And a video / audio data stream is compared when restarting.

3 (a) is a diagram showing audio / video data according to a pause and a recording restart command during reproduction of a moving picture file using the portable terminal.

That is, at the time of reproducing the moving image file, a pause command 300 by the user is inputted into the video / audio data that has come in at regular intervals. Then, the video / audio data is temporarily disconnected, and when the user issues a recording restart command 302, the video / audio data is reproduced again.

3B is a diagram showing conventional video / audio data in which the intervals of the audio data signals become unstable due to the restart of recording after a pause in FIG. 3A.

In other words, the stream interval of the video / audio data restarted after the pause is widened as compared with the video / audio data maintaining a constant interval, and a case where a plurality of video data are included in one audio data interval Occurs.

Referring to FIG. 3 (c), when the stream is adjusted according to the audio signal coming in at regular intervals in FIG. 3 (b), the video data V [4] The time reversal phenomenon of the data occurs.

That is, if the conventional video / audio data synchronization method is used, the processor can not perform encoding at a proper time, and the video data signal is lost, thereby causing a problem of temporal synchronization being lost.

Referring to FIG. 3 (d), according to the video and audio synchronization method proposed in the present invention, after the recording pause, the audio signal A [3] which is the first incoming audio signal at the time of restarting the recording is discarded, Align the video signal with the audio signal time.

Here, discarding the A [3] signal means that the data is not included in the video recording file.

When a moving picture file is played back, the moving picture is played using the time information inside the moving picture file. The time information is shared by the audio and the video. When the recording is temporarily stopped after the recording is restarted, the time information may be changed.

Therefore, the audio time interval is set to be the same as the timer, and the first incoming audio data after the pause and stop of the recording are not synchronized with the video recording file.

For the above reason, the video and audio data signals after the discarded A [3] are set to the audio signal and the video signal comes in. In case of V [5] Time is less than ', so the elapsed time is set to zero.

In conclusion, three video signals V [3], V [5], and V [6] appear between A [2] and A [4] .

In other words, by allowing the first audio data signal to be recognized as a start signal, the intervals of the audio data signals are made the same, and the interval of the video data signal is compensated, so that a smooth image is generated while noise is small.

4 is a flow chart illustrating a video and audio synchronization method in accordance with the present invention.

Referring to FIG. 4, during recording using a device provided with a video recording function such as a portable terminal or a camcorder, recording is temporarily stopped in response to a pause command by a user (S400).

In step S402, the control unit of the device provided with the video recording function, such as the portable terminal or the camcorder, determines whether a recording restart command is input by the user.

As a result of the determination, if the recording restart command is not received, the controller waits until the recording restart command is received until the recording restart command is received. However, if the recording restart command is received, The audio data signal is recognized as a signal indicating the start of recording, the timer is activated, and the first audio signal is discarded (S404).

Here, discarding the first incoming audio data signal means not including the data in the moving picture recording file.

Then, if the time of the video data signal coming in the same stream as the audio data signal is less than the time when the previous video data signal is inputted, the elapsed time is made 0 (S406).

After step 406 is performed, recording of a device provided with a video recording function such as a portable terminal or a camcorder device is restarted (S408).

In summary, when the video is recorded, the internal timer is used to input the audio data at the same time interval. In the environment where the frame rate is low or after pausing at the recording, It is possible to produce a stable, noise-free and smooth image by not including it in a moving image recording file.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art.

Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

It uses the internal timer to input the audio data at the same time interval by using the internal timer when recording the video, so that only the audio data coming in after the restart of the recording is synchronized with the video and audio, By not including it in the file, it is possible to produce a stable, noise-free and smooth image.

Claims (6)

In a device for restarting recording after a recording pause, A modem chip (MSM) for performing an overall control operation of the system, for activating a timer when the first audio signal is received when the recording is restarted, and then discarding the first audio data; A DSP chip connected to the modem chip for controlling storage of audio data and audio elapsed time after the first audio data; A camera unit connected to the DSP chip for capturing video data in a recording mode and transmitting a predetermined number of frames per second to the DSP chip; And And a memory unit connected to the DSP chip to store audio data and audio elapsed time transmitted from the modem chip and store the elapsed time as video elapsed time each time video data is input, Wherein the modem chip comprises an elapsed time calculator for comparing the time of the incoming video data with the incoming video data and the video signal prior to the recording pause command in the restart of the video recording. The method according to claim 1, Wherein the modem chip further comprises a timer for correcting the elapsed time and increasing the elapsed time each time an audio data signal is input. delete The method according to claim 1, Wherein the elapsed time calculating unit sets the elapsed time to 0 when the incoming video data such as audio data at the time of restarting the recording is less than the time at which the video data before the recording pause command is received. Recognizing the first audio data signal that is received when the recording is restarted after the recording pause, as a recording start signal, and operating the timer; Discarding the first audio data signal after activating the timer; Comparing a time at which a video data signal incoming as an audio data signal and a video data signal preceding a recording pause command are input at the time of restarting the video recording; If the video data signal received as the audio data signal at the time of restarting the recording is smaller than the time at which the previous video data signal was received, setting the elapsed time to 0; And And performing recording in accordance with the timer being operated. 6. The method of claim 5, Wherein the discarded first audio data signal is not included in the moving picture recording file.

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