Method for detecting data variation

[0026] Example 1

[0027] A method for detecting data changes, including the following steps:

[0028] (1) Open up an area as large as the display buffer to be detected as the comparison buffer, then divide the display buffer and the comparison buffer into several corresponding buffer blocks, and then divide each buffer block All are divided into large dot graphs composed of K M×N dot graphs;

[0029] (2) Then scan the dots of the display buffer block and the comparison buffer block in rounds, each scan is divided into K times, and each scan respectively scans the content of one/k dots corresponding to the display buffer block and the comparison buffer block. The scanning is to compare whether the content of each corresponding dot on the above two buffer blocks is the same. Each time you scan, the content that has been scanned in this round will not be scanned again. The K, M, and N are all Is a positive integer.

[0030] In step (2), if a change is found at any point in the two corresponding buffer blocks during each scan, then the position will be scanned in a block range from 256×256 to 1024×768, using the All the changed data in the block range, update the data in the comparison buffer, and compress or uncompress it, and send it to the client at the end of this scan or this round of scanning. The block range does not include this time or the current round has been carried out. Fully scan the parts one by one.

[0031] Each scan described is a scan that meets at least one or more of the following conditions:

[0032] (1) At least one of the M consecutive horizontal dots is scanned;

[0033] (2) At least one of the N consecutive vertical dots is scanned;

[0034] (3) At least one dot is scanned in any [M/2+1]×[N/2+1] matrix.

[0035] The one dot may uniformly correspond to or uniformly represent 1, 2, 4, 8 or 16 pixels.

[0036] The display buffer refers to the pixel data memory corresponding to the display in the display, and the comparison buffer is a memory that stores the content of the display buffer after the latest update, and has a one-to-one correspondence with the display buffer. At the beginning, it is necessary to copy all the data in the display buffer to the comparison buffer, and then update the content of the comparison buffer according to the changes in the display buffer during a comprehensive scan one by one. Assume that the order of the data stored in the two buffers corresponds to the position of the display first from left to right, and then from top to bottom. The display buffer starts with the first pixel corresponding to the upper left corner of the display; the last pixel corresponds to the lower right corner of the display. The content displayed on the first line of the display is stored at the beginning of the display buffer.

[0037] Embodiment 2 The method described in Embodiment 1 is used to detect the display buffer

[0038] Divide each display buffer block and comparison buffer block into a large dot pattern composed of 4 4×4 dot dot patterns, and each scan displays the contents of a quarter of the dot in the buffer area. Others are as described in the embodiment. The steps described in the operation. Each scan of the dots is shown in Figure 1; Figure 1 is a schematic diagram of the scanning process of scanning each 4×4 dot when the method of Example 1 is used to detect the display buffer. Each dot has 4 same diagrams. 4×4 dot diagram (where A is the diagram of the first scan dot, B is the diagram of the second scan dot, C is the diagram of the third scan dot, D is the diagram of the fourth scan dot);

[0039] The black dots will be scanned during this scan, and the blank dots will not be scanned. We superimpose these 4 scans to see that every dot of the 4×4 dots is covered.

[0040] If the entire buffer is not divisible by 4, the remaining part is scanned from the left, upper, or upper left part of each corresponding dot pattern.

[0041] For the sake of simplicity and convenience, the K-th scan of the dot map is to place the first column of the K-1 scan of the dot map after the last column.

[0042] Embodiment 3 The method described in Embodiment 1 is used to detect the display buffer

[0043]According to the steps described in embodiment 1, the resolution of the display buffer is 25600×3072, the color depth is 32 bits, that is, it is represented by 4 bytes, and it is divided into buffer blocks composed of 4 rows and 25 columns. The resolution of the block is 1024×768. Open up an area as large as the display buffer to be detected (25600×3072×4=314572800 bytes) as the comparison buffer (also 314572800 bytes), and divide each display buffer block and comparison buffer block It is a large dot pattern composed of 9 9×9 dot patterns, each dot represents a pixel. These 9 large dot patterns are used for 9 scans respectively, and then the corresponding display buffer and comparison buffer are scanned in rounds. Each round is divided into 9 scans, each scan of one-ninth of the content of each buffer block, the scan is to compare the content of the corresponding outlets of the corresponding blocks of the above two buffers one by one, and the corresponding outlets are Refers to the same location of the above two buffers.

[0044] When the system is idle or at a certain frequency, the scanning program is called once. Every 9 times the scanning program is called to complete a round of scanning. If no data changes are found in each scan of this round, it means that the display buffer is in this scanning period. There is no updated content; if a data change is found in a certain scan, it means that the display buffer has no updated content during the current scan period.

[0045] Figure 2 is a schematic diagram of the first scanning dots when scanning each 9×9 dots when the method of the present invention is used to detect the buffer area. The diagram of the dots consists of 4 identical ones and used for the 9× of the first scan. 9-dot map composition;

[0046] Fig. 3 is a schematic diagram of the sixth scanning dots when scanning each 9×9 dots when the method of the present invention is used to detect the buffer area. The diagram of the dots consists of 4 identical ones and used for the 9× of the sixth scanning 9-dot map composition.

[0047] It should be noted that both 1024 and 768 are not divisible by 9, leaving 7 and 3 points respectively, and the remaining part is scanned from the left, upper or upper left part of each corresponding dot map.

[0048] The black dots will be scanned during this scan, and the blank dots will not be scanned. We superimpose these 9 scans to see that each of the 9×9 dots is covered.

[0049] After each scan, compare the dots of each display buffer block in this scan with the update changes of the corresponding dots of each comparison buffer block. If a buffer block is found to be changed, scan the buffer block one by one, update all the changed data in the buffer block, update the data in the comparison buffer, and compress or uncompress it. In this scan or Send to the client at the end of this round of scanning, and then scan the remaining buffer blocks this time. If it is found that there is a data change on the edge of a certain block, it is necessary to scan the blocks adjacent to the edge one by one, and follow similar operations.

[0050] For the sake of simplicity and convenience, the K-th scan of the dot map is to place the first column of the K-1 scan of the dot map after the last column.

[0051] Embodiment 4 The method described in embodiment 1 is used to detect the display buffer

[0052] According to the steps described in embodiment 1, the resolution of the display buffer is 25600×3072, the color depth is 16 bits, that is, it is represented by 2 bytes, and it is divided into buffer blocks composed of 4 rows and 25 columns. The resolution of the block is 1024×768. Open up an area as large as the display buffer to be detected (25600×3072×2=157286400 bytes) as a comparison buffer (also 157286400 bytes), and divide each display buffer block and comparison buffer block It is a large dot pattern composed of three 4×3 dot dot patterns. Each dot represents two pixels in the horizontal direction. Each scan corresponds to the display buffer block and compares the contents of one-third of the dot in the buffer block. Others follow the steps described in Example 3. Each scan of the dots is shown in Figure 4; Figure 4 is a schematic diagram of the scanning process of scanning each 4×3 dot when the method of Example 1 is used to detect the display buffer. Each dot has 4 same diagrams. 4×3 dot map (where A is the schematic diagram of the first scan of the dots, B is the schematic diagram of the second scan of the dots, and C is the schematic diagram of the third scan);

[0053] The black dots will be scanned during this scan, and the blank dots will not be scanned. We superimpose these 3 scans to see that every dot of the 4×3 dots is covered.

[0054] For a display buffer composed of multiples of 1024×768, the horizontal direction can be divisible by 8 (4 dots represent 8 pixels), and the vertical direction can be divisible by 3 without generating a remainder.

[0055] Refer to Example 3 for other operations.

[0056] The current PC is obviously more efficient to operate on 32-bit data than on 16-bit data, so it is more appropriate for us to represent two 16-bit pixels with one dot. When the computer has significantly improved the efficiency of 64-bit data operations compared to 32-bit data operations, we can also use one dot to represent two 32-bit pixels in the horizontal direction, or one dot can represent four 16-bit pixels in the horizontal direction. Similarly, for 128-bit or 256-bit computers, we can put one dot to represent more pixels in the horizontal direction. In short, a dot can correspond to or represent 1, 2, 4, 8 or 16 pixels uniformly.

[0057] In the super-large screen splicing display wall, we often find that most of the pixels are unchanged, and a small part are changed, and individual areas need to be animated. The more pixel regions that do not change, the more obvious the effect of the present invention. Make the computer concentrate on processing the changed content, make the animation information be displayed on the client in time, and achieve a faster refresh rate as much as possible. Conversely, the more pixels that change, the faster this method detects the changed content, and the present invention does not significantly increase the detection time.