发明名称 |
Methods and systems for efficient image cropping and analysis |
摘要 |
A system and method for cropping a license plate image to facilitate license plate recognition by obtaining an image that includes the license plate image, dividing the image into multiple sub-blocks, computing an activity measure for each sub-block; determining an activity threshold, determining that a sub-block is an active sub-block by comparing the activity measure for the sub-block with the activity threshold, generating a second image of the license plate information, where the second image includes the active sub-block, and obtaining the license plate information based on the second image. |
申请公布号 |
US9569681(B2) |
申请公布日期 |
2017.02.14 |
申请号 |
US201414249809 |
申请日期 |
2014.04.10 |
申请人 |
Xerox Corporation |
发明人 |
Bala Raja;Burry Aaron M. |
分类号 |
G06K9/32;G06T3/00;G06T7/00 |
主分类号 |
G06K9/32 |
代理机构 |
MH2 TECHNOLOGY LAW GROUP LLP |
代理人 |
MH2 TECHNOLOGY LAW GROUP LLP |
主权项 |
1. A method comprising:
obtaining an image comprising license plate information; dividing the image into a plurality of sub-blocks; computing a spatial activity measure for each sub-block of the plurality of sub-blocks, wherein the spatial activity measure includes a two-dimensional discrete cosine transform (DCT); generating a one-dimensional activity profile for the image based on the spatial activity measure for each sub-block; determining an activity threshold based on a predetermined percentage; determining that a sub-block of the plurality of sub-blocks is an active sub-block by comparing the spatial activity measure for the sub-block with the activity threshold; generating, using one or more processors, a second image of the license plate information, wherein the second image comprises the active sub-block; and obtaining the license plate information based on the second image. |
地址 |
Norwalk CT US |