CN104202551A - Method and device for video data acquisition - Google Patents

Abstract

The invention discloses a method and device for collecting video data. The method includes: determining the video resolution currently required; Whether the effective amount is consistent with the amount of data represented by the value included in the currently required video resolution; The size relationship of the video data is processed. Since the effective amount of the video data is monitored in real time by using the synchronous signal of the video in the process of collecting the video, and the effective amount of the monitored video data is determined to be consistent according to the video resolution, and the inconsistency is found to be processed, thereby avoiding data misalignment The resulting error accumulation makes the collection error not affect subsequent video signal collection when the video signal source returns to normal.

Description

Method and device for collecting video data

technical field

The invention relates to digital signal processing technology, in particular to a method and device for collecting video data.

Background technique

The main function of video data acquisition (Video Capture) is to convert the analog video signal output by the camera, video recorder, and TV into a digital video signal for subsequent processing and transmission.

General-purpose embedded processors tend to use more on-chip storage resources than dedicated video processors, which is very helpful for improving system performance. However, the shortcoming of general-purpose processors is that there is no dedicated video acquisition interface. Since the field-programmable gate array (Field-Programmable Gate Array, FPGA) has the characteristics of flexible interface expansion, the embedded video processing currently used Most of the systems use FPGA+general-purpose processor architecture.

Real-time video acquisition can be realized by utilizing the flexible advantages of the FPGA interface expansion form. However, in the actual use process, the video source signal is often unstable or suddenly interrupted. The existing video data collection methods focus on the realization of the collection function and the improvement of performance without considering these situations, and continue to collect video data. This makes the collected data error to a large extent, and due to the accumulation of errors, even if the video source signal returns to normal, the error cannot be eliminated, and the collected video data is still wrong. Therefore, the existing video data collection method has the problem that once a collection error occurs when the video source signal is abnormal, the video signal cannot be collected correctly even after the video source signal returns to normal.

Contents of the invention

In view of this, the embodiment of the present invention provides a method and device for collecting video data, which is used to solve the problem that once a collection error occurs when the video source signal is abnormal in the prior art, even after the video source signal returns to normal, the video signal cannot be correctly processed. collection problem.

Embodiments of the present invention provide a method and device for collecting video data, specifically as follows:

In a first aspect, a video data collection method, the method includes:

Determine the currently required video resolution, where the video resolution is the video resolution in the currently required video format;

During the acquisition process, the effective amount of video data is monitored in real time according to the synchronous signal of the video;

Determine whether the effective amount of monitored video data is consistent with the amount of data represented by the value included in the currently required video resolution;

When the judgment result is inconsistent, the video data is processed according to the size relationship between the effective amount of the monitored video data and the amount of data represented by the value included in the currently required video resolution, and the video data obtained after processing The effective amount is consistent with the amount of data represented by the value included in the currently required video resolution.

With reference to the first aspect, in the first possible implementation manner, the video data is processed according to the size relationship between the monitored effective amount of video data and the amount of data represented by the value included in the currently required video resolution. processing, including:

When the effective amount of the monitored video data is less than the amount of data represented by the value included in the currently required video resolution, it is determined that the effective amount of the monitored video data is insufficient, and data completion processing is performed;

When the effective amount of the monitored video data is greater than the amount of data represented by the value included in the currently required video resolution, it is determined that the effective amount of the monitored video data is excessive, and data truncation processing is performed.

In combination with the first aspect and the first possible implementation manner of the first aspect, in the second possible implementation manner, the method further includes:

During the acquisition process, the correctness of the synchronization signal of the video is monitored in real time;

When an error occurs in the synchronous signal of the video, it outputs an instruction to delete the currently transmitted video frame data and waits for a new frame of video data to be collected.

In combination with the first possible implementation manner of the first aspect, in the third possible implementation manner, the real-time monitoring of the effective amount of video data according to the synchronization signal of the video during the acquisition process includes:

During the acquisition process, monitor the effective amount of video data of each row in real time according to the effective video start SAV code and the effective video end EAV code of each row in the video frame;

Whether the effective amount of the video data monitored by the judgment is consistent with the amount of data represented by the value included in the currently required video resolution includes:

It is judged whether the effective amount of the row of video data is consistent with the data amount represented by the value in the horizontal direction included in the currently required video resolution.

In combination with the third possible implementation manner of the first aspect, in the fourth possible implementation manner, when the effective amount of monitored video data is less than the amount of data represented by the value included in the currently required video resolution , determining that the effective amount of the monitored video data is insufficient, and performing data complement processing, including:

When it is determined that the effective amount of the row of video data is less than the amount of data represented by the value in the horizontal direction included in the video resolution, it is determined that the effective amount of the monitored video data is insufficient, and the last collected data is continuously output , until the amount of data represented by the horizontal value included in the video resolution is reached;

When the effective amount of the monitored video data is greater than the amount of data represented by the value included in the currently required video resolution, it is determined that the effective amount of the monitored video data is excessive, and data truncation processing is performed, including:

When it is determined that the effective amount of the row of video data is greater than the amount of data represented by the value on the horizontal direction included in the video resolution, it is determined that the effective amount of the monitored video data exceeds the amount, and the video data collected is suspended. output until the state of the row valid signal of the current row transitions to inactive

In a second aspect, a video data collection device, said device comprising:

A resolution determination unit, configured to determine the currently required video resolution, where the video resolution is the video resolution in the currently required video format;

The first monitoring unit is used to monitor the effective amount of video data in real time according to the synchronous signal of the video during the acquisition process;

A judging unit, configured to judge whether the effective amount of the monitored video data is consistent with the amount of data represented by the value included in the currently required video resolution;

The first execution unit is used to process the video data according to the size relationship between the effective amount of the monitored video data and the amount of data represented by the value included in the currently required video resolution when the judgment result is inconsistent, and The effective amount of video data obtained after processing is consistent with the amount of data represented by the value included in the currently required video resolution.

With reference to the second aspect, in the first possible implementation manner, the first execution unit is further configured to: when the effective amount of monitored video data is less than the amount of data represented by the value included in the currently required video resolution , determine that the effective amount of the monitored video data is insufficient, and perform data complement processing; when the effective amount of the monitored video data is greater than the amount of data represented by the value included in the currently required video resolution, determine that the monitored The effective amount of the video data is excessive, and data truncation processing is performed.

With reference to the second aspect and the first possible implementation manner of the second aspect, in the second possible implementation manner, the device further includes:

The second monitoring unit is used to monitor the correctness of the synchronization signal of the video in real time during the acquisition process;

The second execution unit is configured to output an instruction to delete the currently transmitted video frame data and wait for a new frame of video data to be collected when an error is detected in the synchronous signal of the video.

In combination with the second possible implementation of the second aspect, in the third possible implementation, it is further used to monitor in real time according to the effective video start SAV code and effective video end EAV code of each line in the video frame during the acquisition process the effective amount of video data for the row;

The judging unit is further configured to judge whether the effective amount of the row of video data is consistent with the data amount represented by the value in the horizontal direction included in the currently required video resolution.

With reference to the third possible implementation manner of the second aspect, in a fourth possible implementation manner, the first execution unit is further configured to determine that the effective amount of video data in the row is less than the video resolution included in the The amount of data represented by the value on the horizontal direction determines that the effective amount of the monitored video data is insufficient, and continues to output the last data collected until it reaches the value represented by the value on the horizontal direction included in the video resolution Amount of data; when determining that the effective amount of video data in this line is greater than the amount of data represented by the value on the horizontal direction included in the video resolution, determine that the effective amount of the monitored video data is excessive, and stop collecting Video data is output until the state of the line valid signal of the current line transitions to inactive.

In the technical solution of the embodiment of the present invention, the effective amount of video data is monitored in real time by using the synchronous signal of the video during the process of collecting the video, and the difference between the effective amount of the monitored video data and the value included in the currently required video resolution is judged. Whether the amount of data represented is consistent, and once it is found to be inconsistent, it will be processed, and the video data will be processed according to the size relationship between the effective amount of monitored video data and the amount of data represented by the value included in the currently required video resolution , and the effective amount of video data obtained after processing is consistent with the amount of data represented by the value included in the currently required video resolution, avoiding error accumulation caused by data misalignment, so that when the video signal source returns to normal, the acquisition error It will not affect the subsequent correct video signal acquisition.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For Those of ordinary skill in the art can also obtain other drawings based on these drawings without making creative efforts.

Fig. 1 is the flow chart of a kind of video data collection method in the embodiment 1 of the present invention;

FIG. 2 is a flow chart of another method for collecting video data in Embodiment 1 of the present invention;

3 is a schematic structural diagram of a video acquisition system in Embodiment 2 of the present invention;

Fig. 4 is the flowchart of the video data acquisition method in the second embodiment of the present invention;

5 is a schematic diagram of the BT.656 standard video line format in Embodiment 2 of the present invention;

FIG. 6 is a definition diagram of 8 bits of SAV or EAV in Embodiment 2 of the present invention;

7 is a schematic diagram of an automatic error detection state machine in Embodiment 2 of the present invention;

FIG. 8 is a schematic structural diagram of a video data collection device in Embodiment 3 of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments . Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In order to solve the problem in the prior art that once a collection error occurs when the video source signal is abnormal, the video signal cannot be collected correctly even after the video source signal returns to normal, the embodiment of the present invention provides a video data collection method and device.

In order to clearly understand the solutions of the embodiments of the present invention, concepts involved in the video capture of the present invention will be described below.

Video resolution is a parameter used to measure the amount of data in an image, usually expressed as pixels per inch (ppi), for example: a video resolution of 320*180 refers to its effective pixels in horizontal and vertical directions , and the effective pixels in the horizontal and vertical directions can also represent the amount of data;

A video sequence is composed of N frames. There are generally two scanning methods when acquiring images, one is progressive scanning and the other is interlaced scanning. For interlaced scanning, each frame generally has 2 fields, one is the top field and the other is the bottom field. Assuming that a frame of image has 720 lines, then the top field contains all the even-numbered lines, and the bottom field contains all the odd-numbered lines. For the top field, valid data lines are all even lines of a frame of image, and for the bottom field, valid data lines are all odd lines of a frame of image.

Also, a field is composed of three parts:

Field = vertical blanking top field (First Vertical Blanking) + effective data line (Active Video) + vertical blanking bottom field (Second Vertical Blanking);

Each line of video data is composed of the following four parts:

Line = effective video end sign code (End of Active Video, EAV code) + horizontal blanking (Horizontal Vertical Blanking) + active video start sign code (Start of Active Video, SAV code) + valid data (Active Video).

The solution of the present invention will be described in detail below through specific examples. Of course, the present invention is not limited to the following examples.

Embodiment one

Embodiment 1 of the present invention provides a video data acquisition method, the flow chart of which is shown in Figure 1, specifically comprising the following steps:

Step 101: Determine the currently required video resolution, which is the video resolution in the currently required video format;

Step 102: monitor the effective amount of video data in real time according to the synchronous signal of the video during the acquisition process;

The synchronization signal includes: SAV code and EAV code.

Wherein, the effective amount may refer to the effective data amount of each line of video data, or may refer to the number of effective data lines of one frame of video data;

And in this step 102, can monitor the effective amount of video data of each row; also can monitor the effective amount of video data of the preset row, for example, every other row or two rows are valid for row video data It can also monitor the number of effective data lines of each frame of video data; while monitoring the effective amount of each line of video data, it can also monitor the number of effective data lines of each frame of video data.

When monitoring the effective amount of video data of each line, it is possible to find out whether there is an acquisition error in a timely manner, and the error can be controlled within one line; when monitoring the effective amount of video data of a preset line, it can save money. The monitoring resources of the system can also detect acquisition errors and deal with them accordingly, and the errors can be controlled within the preset lines; when monitoring the effective data lines of each frame of video data, the errors can be controlled within one frame .

Concrete, because each line in the video data all comprises SAV sign indicating number and EAV sign indicating number, therefore, can monitor the effective quantity of this line of video data in real time according to the SAV sign indicating number and EAV sign indicating number of each line in the video frame; The SAV code and EAV code of each line in the video frame can monitor the number of effective data lines of each frame of video data, and can also simultaneously monitor the effective amount of video data and each line of video data in real time according to the SAV code and EAV code of each line in the video frame. The number of effective lines of a frame of video data is monitored.

When monitoring the number of effective data lines of each frame of video data, the effective line counter can be set first. When monitoring each frame, the initial value of the effective line counter is set to 0, and then according to the effective video of each line Start SAV code and effective video end EAV code to determine whether this row is a valid data row, and when this row is a valid data row, add 1 to the count value of the valid row counter.

Step 103: Judging whether the effective amount of the monitored video data is consistent with the amount of data represented by the value included in the currently required video resolution, when the judgment result is consistent, jump to step 102; when the judgment result is inconsistent, Execute step 104;

Since the video resolution contains the effective pixel information of the video picture in the horizontal and vertical directions, the effective pixel information can also represent the amount of data, therefore, the video resolution can be used to measure the effective amount of the monitored video data;

Concretely, when monitoring the effective quantity of video data of this line according to the start SAV code of each line of effective video in the video frame and the end EAV code of effective video in real time during the acquisition process, this step 103 specifically includes:

Judging whether the effective amount of the monitored line video data is consistent with the amount of data represented by the horizontal value included in the currently required video resolution;

When monitoring the effective data line number of each frame of video data according to the SAV code and EAV code of each line in the video frame in real time during the acquisition process, this step 103 specifically includes:

Judging whether the effective amount of the monitored frame video data is consistent with the amount of data represented by the vertical value included in the currently required video resolution, and judging whether the frame still has an effective amount of data;

Now, if this effective line counter is equal to the amount of data represented by the value on the vertical direction of the video resolution, and there is no effective data line in this frame, then it is determined that the effective amount of video data is normal, and jumps to step 102; otherwise , go to step 104.

Step 104: Process the video data according to the size relationship between the monitored effective amount of video data and the amount of data represented by the value included in the currently required video resolution, and the effective amount of video data obtained after processing is the same as the current The required video resolution includes the same amount of data as the value represented.

Specifically, in this step 104, the video data is processed according to the size relationship between the effective amount of the monitored video data and the amount of data represented by the value included in the currently required video resolution, including:

When the effective amount of the monitored video data is less than the amount of data represented by the value included in the currently required video resolution, it is determined that the effective amount of the monitored video data is insufficient, and data complement processing is performed;

When the effective amount of the monitored video data is greater than the amount of data represented by the value included in the currently required video resolution, it is determined that the effective amount of the monitored video data exceeds the amount, and data truncation processing is performed.

Further, if the effective amount of video data monitored in real time during the acquisition process is the effective amount of line video data, then the effective amount of video data monitored is less than the amount of data represented by the value included in the currently required video resolution When it is determined that the effective amount of the monitored video data is insufficient, and the data is supplemented, including:

When it is detected that the effective amount of video data in this line is less than the amount of data represented by the horizontal value included in the video resolution, it is determined that the effective amount of the monitored video data is insufficient, and the last data collected will continue to be output until Reach the amount of data represented by the value in the horizontal direction included in the video resolution;

When the effective amount of the monitored video data is greater than the amount of data represented by the value included in the currently required video resolution, determine that the effective amount of the monitored video data is excessive, and perform data truncation processing, including:

When it is detected that the effective amount of the video data of this line is greater than the data amount represented by the horizontal value included in the video resolution, it is determined that the effective amount of the monitored video data exceeds the amount, and the output of the collected video data is suspended until The state of the row valid signal for the current row transitions to invalid.

If the effective amount of video data monitored in real time during the acquisition process is the number of effective data lines of a frame of video data, then the effective amount of the above-mentioned monitored video data is less than the amount of data represented by the value included in the currently required video resolution When it is determined that the effective amount of the monitored video data is insufficient, and the data is supplemented, including:

When it is detected that the number of effective data lines of a frame of video data is less than the amount of data represented by the value in the vertical direction included in the video resolution, and there is no effective data line in the frame, it is determined that the effective amount of the monitored video data is insufficient, and Continuously output the data of the last line of valid data line collected until reaching the amount of data represented by the vertical value included in the video resolution;

When the effective amount of the monitored video data is greater than the amount of data represented by the value included in the currently required video resolution, determine that the effective amount of the monitored video data is excessive, and perform data truncation processing, including:

When it is detected that the number of effective data lines of a frame of video data is equal to or greater than the amount of data represented by the vertical value included in the video resolution and there are still effective data lines in this frame, it is determined that the effective amount of the monitored video data is excessive , and suspend the output of the collected video data until the status of the valid data row signal of the current frame is changed to invalid.

In the technical solution of Embodiment 1 of the present invention, the effective amount of video data is monitored in real time by using the synchronous signal of the video in the process of collecting video, and the value included in the effective amount of the monitored video data and the currently required video resolution is judged Whether the amount of data represented is consistent, once it is found to be inconsistent, it will be processed, and the video data will be processed according to the size relationship between the effective amount of video data monitored and the amount of data represented by the value included in the currently required video resolution. processing, and the effective amount of video data obtained after processing is consistent with the amount of data represented by the value included in the currently required video resolution, to avoid error accumulation caused by data misalignment, so that when the video signal source returns to normal, the acquisition The error will not affect the subsequent correct video signal acquisition.

Considering that during the video acquisition process, errors may also occur in the synchronous signal, therefore, in order to realize the monitoring of the synchronous signal, preferably, the above-mentioned video acquisition method also includes the following steps as shown in Figure 2:

Step 201: monitor the correctness of the synchronization signal of the video in real time during the acquisition process;

Step 202: When an error is detected in the video synchronization signal, output an instruction to delete the currently transmitted video frame data and wait for a new frame of video data to be collected; when no error is detected in the video synchronization signal, continue to collect.

In the above step 201 to step 202, it is considered that the video data of this frame will be unusable due to an error in the synchronous signal. Therefore, the instruction measure of deleting the currently transmitted video frame data is taken.

It should be noted that step 201 and step 202 are performed after above-mentioned step 101, because the synchronous signal is monitored in real time, and the synchronous signal will appear in each effective data row of video data, therefore, step 201 and above-mentioned step 102 can be executed simultaneously.

The solution of Embodiment 1 of the present invention will be further described below through the BT.6568bitYCbCr4:2:2 standard video with a resolution of 720*576 collected by the camera in Embodiment 2.

Embodiment two

Fig. 3 is the structural representation of the video acquisition system in the embodiment of the present invention two, comprises: camera 31, SAA7115 chip 32, Field Programmable Gate Array (FPGA) 33, Programmable Read-Only Memory (Programmable Read-Only Memory, PROM ) 34, SRAM (StaticRandom Access Memory, SRAM) 35 and follow-up processing module 36;

Among them, the analog video adopts SAA7115 chip 32 for analog-to-digital conversion, and the data video output format can be BT.6568bit YCbCr4:2:2 by configuring the working mode of SAA7115;

FPGA33 is the main processor, which collects digital video data in BT.6568bit YCbCr4:2:2 format after analog-to-digital conversion in real time;

PROM 34, SRAM 35 assist FPGA to realize video data collection.

On the basis of the hardware of the video capture system shown in Figure 3, the video capture method in the second embodiment of the present invention can be implemented, certainly the scheme in the second embodiment of the present invention is not limited to the hardware of the video capture system shown in Figure 3 on the implementation.

Figure 4 is a schematic flow diagram of a video acquisition method in Embodiment 2 of the present invention, including the following steps:

Step 401: the SAA7115 chip converts the collected analog signal of the camera into a digital signal;

Step 402: FPGA collects video;

In Embodiment 2 of the present invention, interlaced scanning is used for collection. At this time, one frame of data video is divided into two fields, and the two fields are a top field containing odd-numbered lines of video data and a bottom field containing even-numbered lines of video data. The BT.656 standard stipulates that one field consists of three parts: vertical blanking top field, valid data line and vertical blanking bottom field. There are 625 lines in each frame of video, 576 lines of effective video data, the effective data of the top field starts from the 23rd line, and the effective data of the bottom field starts from the 335th line. As shown in Figure 5, it is the BT.656 standard video line format, and each line of video data is composed of the following four parts:

Line = active video end flag code (EAV code) + horizontal blanking (Horizontal Vertical Blanking) + active video start flag code (SAV code) + valid data (Active Video).

Wherein, both EAV and SAV are 4 bytes (Bytes), and SAV is followed by valid video data;

The format of the 4 bytes of EAV and SAV is specified as follows (hexadecimal representation below): FF 0000 XY;

Among them, the first three bytes are fixed and must be FF 0000, and the fourth byte (XY) is determined according to the field and blanking information, as shown in Figure 6, the meaning of the 8 bits of SAV or EAV definition, its meaning is as follows:

The highest bit Bit7 is fixed data 1; Bit6 is F: mark field information, 0 when transmitting the top field, and 1 when transmitting the bottom field; Bit5 is V: mark blanking information, 1 when transmitting blanking data, and the transmission is valid When it is video data, it is 0; Bit4 is H: mark EAV or SAV, SAV is 0, EAV is 1; Bit3~Bit0 are protection signals, and their values depend on F, H, V, which play a role in verification. Bit3 is V XOR H; Bit2 is F XOR H; Bit1 is F XOR V; Bit0 is F XOR V XOR H. Effective video data is arranged in the order of Cb, Y, Cr, Y, a line contains 720 bytes Y, 360 bytes Cb and Cr, a total of 1440 bytes.

Step 403: FPGA monitors in real time whether the effective data volume of the video data is consistent with the currently required video resolution; when the monitoring result is consistent, execute step 407; when the monitoring result is inconsistent, execute step 404;

Step 404: Judging whether the effective data volume of the monitoring video data is greater than the data volume represented by the currently required video resolution, if so, then determining that the error type is data excess, and performing step 405; if not, then determining that the error type is insufficient data, Execute step 406;

Step 405: Perform data truncation processing to obtain recovered video data, and execute step 407;

Step 406: Carry out data complement processing to obtain the restored video data, and execute step 407;

Step 407: output to the subsequent processing module, and jump to step 402.

The above step 403 to step 406 can be realized by the automatic error detection state machine shown in FIG. 7 .

The BT.656 format video output by SAA7115 is collected through FPGA. The collection process is controlled by the video collection control state machine. The video collection state machine includes five states: idle state, video collection start state, video collection stage state, and video collection end state and error status. The idle state is the initial state. When the video SAV code arrives, it enters the initial state of video collection; the next state is the state of the video collection stage. If the EAV code is detected, it enters the end state of video collection, otherwise continue to collect video; when the video EAV code arrives , it enters the end state of video capture, and enters the idle state in the next step; the error state indicates that an error occurred during the video capture process, and corresponding error recovery processing is performed. The specific process includes:

When in the idle state, monitor 0xFF0000 data (0xFF0000 is the high byte of each line of video data SAV code and EAV code in the BT.656 standard, as shown in Figure 5), indicating that the synchronization signal arrives;

The video capture initial state inspection mark code is not SAV code (definition of initial code as shown in Figure 5), enters error state;

The status of the video acquisition stage counts the effective data volume of the collected video in real time. When the EAV code of a line of effective video data is detected, check whether the count value is 1440 bytes (720 bytes Y, 360 bytes Cr and 360 bytes Cb). If it is less than 1440 bytes, it enters an error state. When the count value exceeds 1440 bytes, the end code has not yet arrived and enters an error state;

The video capture end state check flag code is not EAV code (EAV code definition is shown in Figure 5), enter the error state, set the line count of the captured video (initial value is 0), and when the EAV state is successfully completed, the line count value increases 1. When the collection of the top field data and one frame of data is finished, check whether the line count value is 288 lines (the number of lines of one field of data) and 576 lines (the number of lines of one frame of data) respectively. If it is not satisfied, enter the error state, If it is satisfied, the collected video data is transferred to the subsequent functional module.

After entering the error state, determine whether the error is caused by insufficient or excessive video data. If it is found that the data collection is insufficient (that is, the amount of data collected in this row is less than the amount of data in each row in the current data format, the amount of data in each row in the current data format It is determined according to the video resolution), then complete the data of the current line, and continuously output the last data collected to the next module until the data volume requirement of each line of the current data format is met; if the data is found to be collected in the current data format When the amount of data in each row of the current data format, the valid signal of the row is still valid (that is, the amount of data collected in this row exceeds the amount of data in each row in the current data format, and the amount of data in each row in the current data format is determined according to the video resolution ), the output of data to the next processing module is suspended until the row valid signal of the current row is converted to an invalid state, so as to avoid error accumulation. If it is judged that the video capture end state check mark code is not EAV code or not SAV code, then the video synchronization signal is wrong, and the follow-up function module is notified to delete the currently transmitted video frame data. After the above operations are completed, the error state is released and enters the idle state, waiting to collect a new frame of video data. When the first vertical blanking SAV code (0xAB) of the top field, the effective data line EAV code (0x9D) of the top field and the SAV code (0x80) of the effective data line of the top field are detected sequentially, it indicates that the subsequent data is the first frame of video data. A valid data, the video capture process starts again.

Embodiment three

Based on the same inventive concept as that of Embodiment 1 of the present invention, Embodiment 3 of the present invention provides a video data acquisition device, the structural diagram of which is shown in FIG. 8 , the device includes: a resolution determination unit 81 and a first monitoring unit 82, Judgment unit 83 and first execution unit 84; wherein:

A resolution determination unit 81 is configured to determine the currently required video resolution, which is the video resolution in the currently required video format;

The first monitoring unit 82 is used to monitor the effective amount of video data in real time according to the synchronization signal of the video during the acquisition process;

A judging unit 83, configured to judge whether the effective amount of the monitored video data is consistent with the amount of data represented by the value included in the currently required video resolution;

The first execution unit 84 is configured to process the video data according to the size relationship between the effective amount of the monitored video data and the amount of data represented by the value included in the currently required video resolution when the judgment result is inconsistent, And the effective amount of video data obtained after processing is consistent with the data amount represented by the value included in the currently required video resolution.

Preferably, the first execution unit 84 is further configured to determine that the effective amount of the monitored video data is insufficient when the effective amount of the monitored video data is less than the amount of data represented by the value included in the currently required video resolution, And perform data complement processing; when the effective amount of the monitored video data is greater than the amount of data represented by the value included in the currently required video resolution, determine that the effective amount of the monitored video data is excessive, and perform data truncation processing .

Preferably, the device also includes:

The second monitoring unit 85 is used to monitor the correctness of the synchronization signal of the video in real time during the acquisition process;

The second execution unit 86 is configured to output an instruction to delete the currently transmitted video frame data and wait for a new frame of video data to be collected when an error is detected in the video synchronization signal.

Preferably, the first monitoring unit 82 is further used to monitor the effective amount of the line of video data in real time according to the start SAV code and the end EAV code of each line of effective video in the video frame during the acquisition process;

The judging unit 83 is further configured to judge whether the effective amount of the row of video data is consistent with the data amount indicated by the value in the horizontal direction included in the currently required video resolution.

Preferably, the first executing unit 84 is further configured to determine that the effective amount of the video data in the row is less than the amount of data represented by the value in the horizontal direction included in the video resolution, and determine that the effective amount of the monitored video data is insufficient, And continue to output the last collected data until it reaches the amount of data represented by the horizontal value included in the video resolution; when it is determined that the effective amount of video data in this row is greater than the value represented by the horizontal value included in the video resolution When the amount of data is exceeded, it is determined that the effective amount of the monitored video data exceeds the amount, and the output of the collected video data is stopped until the state of the line valid signal of the current line is converted to invalid.

Those skilled in the art should understand that the embodiments of the present invention may be provided as methods, systems, or computer program products. Accordingly, the present invention can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each procedure and/or block in the flowchart and/or block diagram, and a combination of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a An apparatus for realizing the functions specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart or blocks of the flowchart and/or the block or blocks of the block diagrams.

While preferred embodiments of the invention have been described, additional changes and modifications to these embodiments can be made by those skilled in the art once the basic inventive concept is appreciated. Therefore, it is intended that the appended claims be construed to cover the preferred embodiment as well as all changes and modifications which fall within the scope of the invention.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (10)

1. a video data acquiring method, is characterized in that, described method comprises:

Determine the video resolution of current needs, described video resolution is the video resolution under the video format of current needs;

In gatherer process, monitor in real time the effective dose of video data according to the synchronizing signal of video;

Whether the represented data volume of value that the effective dose of video data that monitors of judgement and the video resolution of current needs comprise is consistent;

In judged result while being inconsistent, magnitude relationship between the represented data volume of the value that comprises according to the video resolution of the effective dose of the video data monitoring and current needs is processed video data, and the represented data volume of the value that comprises of the effective dose of video data obtaining after processing and the video resolution of current needs is consistent.

2. the method for claim 1, is characterized in that, the magnitude relationship between the represented data volume of value that the effective dose of the video data that described basis monitors and the video resolution of current needs comprise is processed video data, comprising:

In the time that the effective dose of the video data monitoring is less than the represented data volume of value that the video resolution of current needs comprises, determines the effective dose deficiency of the described video data monitoring, and carry out the processing of data polishing;

In the time that the effective dose of the video data monitoring is greater than the represented data volume of value that the video resolution of current needs comprises, determines the effective dose excess of the described video data monitoring, and carry out data truncation.

3. method as claimed in claim 1 or 2, is characterized in that, described method also comprises:

The correctness of the synchronizing signal of Real-Time Monitoring video in gatherer process;

Occur when wrong in the synchronizing signal that monitors video, output delete current transmission video requency frame data instruction and etc. new one-frame video data to be collected.

4. method as claimed in claim 2, is characterized in that, describedly in gatherer process, comprises according to the effective dose of the synchronizing signal monitoring video data of video in real time:

In gatherer process, in real time finish EAV code and monitor the effective dose of this row video data according to the initial SAV code of every row effective video and effective video in frame of video;

Whether the effective dose of the video data that described judgement the monitors data volume represented with the value that the video resolution of current needs comprises be consistent, comprising:

Judge that whether the represented data volume of value transversely that the effective dose of this row video data and the video resolution of current needs comprise is consistent.

5. method as claimed in claim 4, it is characterized in that, when the effective dose of the described video data monitoring is less than the represented data volume of value that the video resolution of current needs comprises, determine the effective dose deficiency of the described video data monitoring, and carry out the processing of data polishing, comprising:

In the time that the effective dose that monitors this row video data is less than the represented data volume of value transversely that described video resolution comprises, determine the effective dose deficiency of the described video data monitoring, and last data collecting are continued to output, until reach the represented data volume of value transversely that described video resolution comprises;

In the time that the effective dose of the video data monitoring is greater than the represented data volume of value that the video resolution of current needs comprises, determine the effective dose excess of the described video data monitoring, and carry out data truncation, comprising:

In the time that the effective dose that monitors this row video data is greater than the represented data volume of value transversely that described video resolution comprises, determine the effective dose excess of the described video data monitoring, and end the output of the video data that collects, until that the state of the row useful signal of current line is converted to is invalid.

6. a video data acquiring device, is characterized in that, this device comprises:

Resolution determining unit, for determining the video resolution of current needs, described video resolution is the video resolution under the video format of current needs;

The first monitoring means, for monitoring in real time the effective dose of video data according to the synchronizing signal of video at gatherer process;

Judging unit, whether consistent for judging the represented data volume of value that the effective dose of the video data monitoring and the video resolution of current needs comprise;

The first performance element, for in judged result while being inconsistent, magnitude relationship between the represented data volume of the value that comprises according to the video resolution of the effective dose of the video data monitoring and current needs is processed video data, and the represented data volume of the value that comprises of the effective dose of video data obtaining after processing and the video resolution of current needs is consistent.

7. device as claimed in claim 6, it is characterized in that, described the first performance element, be further used in the time that the effective dose of the video data monitoring is less than the represented data volume of value that the video resolution of current needs comprises, determine the effective dose deficiency of the described video data monitoring, and carry out the processing of data polishing; In the time that the effective dose of the video data monitoring is greater than the represented data volume of value that the video resolution of current needs comprises, determines the effective dose excess of the described video data monitoring, and carry out data truncation.

8. the device as described in claim 6 or 7, is characterized in that, described device also comprises:

The second monitoring means, for the correctness of the synchronizing signal at gatherer process Real-Time Monitoring video;

The second performance element, for occurring in the synchronizing signal that monitors video when wrong, output delete current transmission video requency frame data instruction and etc. new one-frame video data to be collected.

9. device as claimed in claim 7, is characterized in that, described the first monitoring means is further used in gatherer process in real time finishing EAV code and monitoring according to the initial SAV code of every row effective video and effective video in frame of video the effective dose of this row video data;

Described judging unit, is further used for judging that whether the represented data volume of value transversely that the effective dose of this row video data and the video resolution of current needs comprise is consistent.

10. device as claimed in claim 9, it is characterized in that, described the first performance element, be further used for being less than in the effective dose of determining this row video data the represented data volume of value transversely that described video resolution comprises, determine the effective dose deficiency of the described video data monitoring, and last data collecting are continued to output, until reach the represented data volume of value transversely that described video resolution comprises; In the time determining that the effective dose of this row video data is greater than the represented data volume of value transversely that described video resolution comprises, determine the effective dose excess of the described video data monitoring, and end the output of the video data that collects, until that the state of the row useful signal of current line is converted to is invalid.