KR20150085665A - Apparatus and method for processing image - Google Patents

Abstract

The present invention relates to an apparatus and a method for processing an image. According to an embodiment of the present invention, the apparatus for processing an image comprises: a digital signal processing unit including a hardware decoder which decodes video and voice signals; and a main processor monitoring a condition of the digital signal processing unit, responding to an event signal which shows occurrence of an error of the digital signal processing unit and loading a software decoder if the signal is not received from the digital signal processing unit, and decoding the video and voice signals by the software decoder.

Description

[0001] APPARATUS AND METHOD FOR PROCESSING IMAGE [0002]

The present invention relates to an image processing apparatus and method.

A video recorder such as a digital video recorder or a network video recorder is connected to at least one surveillance camera and stores the image received from the selected camera, decodes and displays the image, and outputs the image to the monitor.

Such a video recording and storing device is equipped with a DSP (digital signal process) chip and a main chip. In this case, if the DSP chip is broken due to an unexpected problem such as a codec, a memory, or a hardware error, a function of resetting the DSP chip by itself is provided. However, since an image input to the video recording apparatus can not be decoded while a plurality of DSP chips are being multiplexed, there arises a problem that the video is stopped or not displayed. In this case, the user loses important video information and can not normally record or output the recorded video or live video.

Japanese Laid-Open Patent Publication No. 2011-255406

SUMMARY OF THE INVENTION It is a technical object of the present invention to provide a digital signal processing apparatus and a digital signal processing method, And to provide a video processing apparatus and method capable of maintaining the same.

According to an aspect of the present invention, there is provided an image processing apparatus comprising: a digital signal processor including a hardware decoder for decoding video and audio signals; And a controller for monitoring the state of the digital signal processor and loading a software decoder in response to an event signal indicating occurrence of an error of the digital signal processor when the signal is not received from the digital signal processor, And a main processor for decoding the decoded data into a software decoder.

In the present invention, when a signal is received from the digital signal processing unit in which the error is recovered, the main processor terminates the operation of the software decoder and restarts the operation of the hardware decoder.

In the present invention, the main processor software-decodes an intra frame of a video signal of a group of pictures (GOP) unit, or performs software decoding by adjusting the resolution of the video signal to a lower level.

According to an aspect of the present invention, there is provided an image processing method including: a hardware decoding step of decoding an image and a speech signal using a hardware decoder included in a digital signal processing unit; Generating an event signal indicating an error occurrence of the digital signal processing unit when a signal is not received from the digital signal processing unit; And a software decoding step of loading a software decoder in response to the event signal and decoding the video and audio signals to the software decoder.

The method may further include stopping the operation of the software decoding and resuming the operation of hardware decoding when a signal is received from the digital signal processing unit in which the error is recovered.

In the present invention, the software decoding step comprises software decoding the intra frame of the video signal in a group of picture (GOP) unit, or performing software decoding by adjusting the resolution of the video signal to a lower level .

As described above, according to the present invention, when an error occurs in a digital signal processing unit that performs hardware decoding, software decoding is performed until an error is recovered, thereby preventing loss of image information and maintaining normal storage or output of an image .

1 is a block diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention.
2 is a diagram illustrating software decoding in accordance with an embodiment of the present invention.
3 is a flowchart illustrating an operation of an image processing method according to an exemplary embodiment of the present invention.

Brief Description of the Drawings The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described in conjunction with the accompanying drawings. It should be understood, however, that the present invention is not limited to the embodiments set forth herein, but may be embodied in many different forms and includes all conversions, equivalents, and alternatives falling within the spirit and scope of the present invention . BRIEF DESCRIPTION OF THE DRAWINGS The above and other aspects of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof. The terms first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. .

1 is a block diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention. Referring to FIG. 1, an image processing apparatus includes a plurality of network cameras 100, a network 200, an image processing means 300, and a display means 400.

At least one network camera 100 is installed in an arbitrary area. The network camera 100 outputs a captured image as a digital video signal and outputs the captured video image to a video storage unit 400 such as a digital video recorder or a network video recorder through the network 200. The network camera 100 may be a speed dome camera disposed at a fixed position of a specific place. Also, the network camera 100 may be constituted by a single fixed camera having a fixed lens and a fixed photographing range, or a pan-tilt-zoom (PTZ) camera having a variable photographing range. Here, the PTZ camera can easily change various surveillance areas with one camera by pan operation rotated in the horizontal direction, tilt operation rotated in the vertical direction, and zoom in / zoom out operation .

When the hardware decoder is not operated due to an error during decoding or decoding of the video and audio signals captured by at least one or more network cameras 100 by the hardware decoder, the video processing unit (300) To thereby prevent loss of video and audio information and to maintain normal storage or output of video and audio information.

The image processing means 300 may include a digital signal processing unit 310, a main processor 330, and a RAM (read access memory) 350.

The digital signal processing unit 310 reduces noise of video and audio signals input from the network camera 100 and performs gamma correction, color filter array interpolation, color matrix, , Color correction, color enhancement, and the like. The digital signal processing unit 310 can also functionally perform color processing, blur processing, edge emphasis processing, image analysis processing, image recognition processing, image effect processing, and the like.

The digital signal processor 310 may include a hardware decoder 311. The hardware decoder 311 decodes video and audio signals input from the network camera 100. Here, the hardware decoder 311 is a decoder which is provided in a built-in form in the digital signal processor 310 and is composed of circuit logic. Generally, when the hardware decoder 311 decodes video and audio signals, the decoded video and audio signals under the control of the main processor 330 are stored in the video processing means 300, .

The main processor 330 controls the overall operation of the image processing means 300, and in particular monitors the digital signal processing unit 310. Here, the term " monitoring " refers to a period of receiving a signal (e.g., a decoding completion signal in response to a decoding request) periodically from the digital signal processing section 310 and outputting a control signal (for example, Image processing signals, etc.) to the digital signal processor 310. [

The main processor 330 loads the software decoder 335 from the RAM 350 when the signal from the digital signal processor 310 is not received during the monitoring of the digital signal processor 310, ) Performs software-to-video decoding on video and audio signals.

The main processor 330 may include an event determination unit 331, a software decoding unit 333, and a control unit 335.

The event determination unit 331 generates an event when a signal is not received from the digital signal processing unit 310 during the monitoring of the digital signal processing unit 310. [ If no signal is received from the digital signal processing unit 310, the digital signal processing unit 310 may fail due to an unexpected problem such as a codec, a memory, or a hardware error in the digital signal processing unit 310. In this case, Performs its own reset. When the digital signal processor 310 performs the reset, the hardware decoder 311 stops operating.

The software decoding unit 333 loads the software decoder 531 from the RAM 350 in response to the event generation signal of the event determination unit 331 and performs software decoding on the video and audio signals. Here, the software decoder 531 performs the decoding operation until the operation of the hardware decoder 531 is stopped and the error is recovered. Also, the software decoder 351 decodes the video and audio signals in software by using a library such as ffmpeg. The software decoder 351 is a codec library that can be used for video and audio. H.264, MPEG-4, and MJPEG can be used for video, and AAC, MP3, etc. for audio.

The control unit 335 controls operations of the software decoder 333 and the hardware decoder 311 in accordance with event generation and disappearance and controls the operations of the software decoder 311 and the hardware decoder 311 through comparison of the hardware decoder 311 and the software decoder 351, 351). The control unit 335 determines whether or not the performance of the software decoder 351 operated in the software decoding unit 333 can replace the performance of the hardware decoder 311, Software decoding, or software decoding by adjusting the resolution of the video signal to a lower level.

2 is a view for explaining the adjustment of the decoding amount of the software decoder 351 operated in the software decoding unit 333. [

An image received from the network camera 100 includes an intra (I) frame, a predicted (P) frame and bidirectional (B) frames included in a video frame picture group (GOP) do. An intra (I) frame is an independent frame that is compressed without reference to previous frames as a key frame, and has the highest image quality and the largest capacity. The prediction (P) frame is a frame based on the information of the previous intra (I) frame or the previous prediction (P) frame, and the image quality and the capacity are medium. The prediction (P) frame compresses only the changed contents with reference to the previous intra (I) frame or the previous prediction (P) frame. The intra (I) frame and the prediction (P) frame are used as reference frames for the next other frames. A bidirectional (B) frame has the lowest image quality and capacity, and requires a front and back reference frame, i.e., an intra (I) frame and a prediction (P) frame.

The control unit 335 controls the prediction of the P picture frame and the bidirectional (B) frame of the video signal of the GOP (group of pictures) unit when the performance of the software decoder 351 can not replace the performance of the hardware decoder 311 (I) frame and software decoding only the intra (I) frame.

If the performance of the software decoder 351 can not replace the performance of the hardware decoder 311, the control unit 335 may set the resolution to a resolution lower than the resolution of the current image (for example, 1920 x 1080) (For example, 720 x 480), and to control software decoding of a lower resolution image.

When an event occurs due to an error of the digital signal processing unit 310, when the software decoder 351 operating in the software decoding unit 333 decodes the video and audio signals, the software decoder 351 decodes the video and audio signals under the control of the main processor 330 Video and audio signals are stored in the image processing means 300 or outputted to the display means 400 as live images.

When the digital signal processor 310 performs its own reset function to recover the error, the main processor 330 receives the signal from the digital signal processor 310 again. In this case, the event determination unit 330 generates an event cancellation signal. In response to the event cancellation signal, the control unit 335 interrupts the operation of the software decoding unit 333, resumes the operation of the hardware decoder 311, and controls the video and audio signals to be decoded by the hardware decoder 311 .

If an error occurs in the digital signal processing unit performing hardware decoding, software decoding is performed until the error is recovered, thereby preventing loss of image information and maintaining normal storage or output of the image.

The display means 400 displays the video and audio signals processed by the video processing means 300. The display means 400 may divide and display at least one channel image to be monitored by the user. That is, the display means 400 can divide the screen into two, four, eight, etc., and display the image of each channel on the divided screen. The display means 400 may include a liquid crystal display panel (LCD), an organic light emitting display panel (OLED), and an electrophoretic display panel (EPD). The display means 400 may be provided as a touch screen so as to receive input through a user's touch, and may operate as an input interface.

In the present embodiment, the description has been given only to the image processing means 300 such as a digital video recorder or a network video recorder. However, the present invention is not limited thereto, and can be implemented in any image processing apparatus having a digital signal processing unit and a main processor.

Next, an image processing method according to an embodiment of the present invention will be described with reference to FIG. The image processing method according to the present invention can be performed in the image processing means with the help of peripheral components as shown in FIG. In the following description, the description of the parts that are the same as those in FIG. 1 and FIG. 2 will be omitted.

The image processing means uses a hardware decoder included in the digital signal processing unit

Hardware decoding for decoding the video and audio signals is performed (S110). When the hardware decoding is performed, the decoding result may be stored in the image processing means or output to the display means.

When the main processor for monitoring the digital signal processing unit fails to receive a signal from the digital signal processing unit, it generates an event signal indicating occurrence of an error in the digital signal processing unit (S120). When the main processor fails to receive a signal from the digital signal processing unit, the main processor malfunctions due to an unexpected problem such as codec, memory, or hardware error in the digital signal processing unit. In this case, the main processor generates an event.

The main processor loads the software decoder in response to the event signal, and performs software decoding to decode the video and audio signals into a software decoder (S130). When an event signal is generated, the digital signal processing unit performs resetting, and the digital signal processing unit replaces the decoding operation during software reset with software decoding. When the software decoding is performed, the decoding result may be stored in the image processing means or output to the display means. Herein, when the performance of the software decoder can not replace the performance of the hardware decoder, the main processor misses the prediction (P) frame and the bidirectional (B) frame from the decoding in the GOP (group of picture) ) Frame, or to adjust the resolution to a lower resolution (for example, 720 x 480) than the resolution of the current image (e.g., 1920 x 1080) Decoded.

The main processor determines whether a signal is received from the digital signal processing unit in which the error is recovered through reset (S140). If the signal is not received from the digital signal processing unit, the software decoding operation is continued.

When a signal is received from the recovered digital signal processor, the main processor generates an event cancel signal, terminates the operation of software decoding, and resumes the operation of hardware decoding (S140).

The various embodiments of the invention are not intended to limit the scope of the invention in any way. For brevity of description, descriptions of conventional electronic configurations, control systems, software, and other functional aspects of such systems may be omitted. Also, the connections or connection members of the lines between the components shown in the figures are illustrative of functional connections and / or physical or circuit connections and may be replaced or additionally provided with various functional connections, physical connections , Or circuit connections. Also, unless stated otherwise such as "essential "," importantly ", and the like, it may not be a necessary component for the practice of the present invention.

The use of the terms "above" and similar indication words in the specification of the present invention (particularly in the claims) may refer to both singular and plural. In addition, in the present invention, when a range is described, it includes the invention to which the individual values belonging to the above range are applied (unless there is contradiction thereto), and each individual value constituting the above range is described in the detailed description of the invention The same.

Unless there is explicitly stated or contrary to the description of the steps constituting the method according to the invention, the steps may be carried out in any suitable order. The present invention is not necessarily limited to the order of description of the above steps. The use of all examples or exemplary language (e.g., etc.) in this invention is for the purpose of describing the present invention only in detail and is not to be limited by the scope of the claims, It is not. It will also be appreciated by those skilled in the art that various modifications, combinations, and alterations may be made depending on design criteria and factors within the scope of the appended claims or equivalents thereof.

Accordingly, the spirit of the present invention should not be construed as being limited to the above-described embodiments, and all ranges that are equivalent to or equivalent to the claims of the present invention as well as the claims .

100: network camera 200: network
300: image processing means 310: digital signal processing unit
311: Hardware decoder 330: Main processor
331: Event determination unit 333: Software decoding unit
335: control unit 350: RAM
351: Software decoder 400: Display means

Claims (6)

A digital signal processor including a hardware decoder for decoding video and audio signals; And
The method comprising: monitoring a state of the digital signal processing unit; loading a software decoder in response to an event signal indicating occurrence of an error in the digital signal processing unit when the signal is not received from the digital signal processing unit; And a main processor for decoding the image data with a decoder. The information processing apparatus according to claim 1,
And terminates the operation of the software decoder and resumes the operation of the hardware decoder when a signal is received from the digital signal processing unit in which the error is recovered. The information processing apparatus according to claim 1,
Wherein software decoding of an intra frame of a video signal of a group of pictures (GOP) unit is performed, or software decoding is performed by adjusting the resolution of the video signal to a lower level. A hardware decoding step of decoding video and audio signals using a hardware decoder included in the digital signal processing unit;
Generating an event signal indicating an error occurrence of the digital signal processing unit when a signal is not received from the digital signal processing unit; And
And a software decoding step of loading a software decoder in response to the event signal and decoding the video and audio signals to the software decoder. The method according to claim 1,
And terminating the operation of the software decoding and resuming the operation of the hardware decoding when a signal is received from the digital signal processor after the error is recovered. 2. The method of claim 1,
And performing software decoding of an intra frame of a video signal of a group of pictures (GOP) unit, or software decoding by adjusting the resolution of the video signal to a lower level.

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