13. A system comprising: one or more processors; and a memory, the memory storing instructions, which when executed by the one or more processors, cause the one or more processors to: receive an image patch of a target document; determine, from the received image patch, a query that indicates a two-dimensional geometric relationship between document features in the target document, the two-dimensional geometric relationship including an indication that the document features in the target document are a horizontally adjacent pair of document features or a vertically adjacent pair of document features; compare the query to an index table of the document features from mixed media documents to identify candidate regions in the mixed media documents that comprise the query, the index table comprising locations of the document features in the mixed media documents; and responsive to comparing the query to the document features in the index table, identify one or more of the mixed media documents comprising the identified candidate regions comprising the query by: adding a weight to an array of an accumulator for each cell in a zone around each pair of document features based on an inverse document frequency associated with each pair of document features, the inverse document frequency being inversely proportional to a number of document pages that contain the image patch; searching the array of the accumulator for the cell with a maximum value; and in response to the maximum value exceeding a threshold, reporting coordinates of the cell as a location of the image patch.
13. A system comprising: one or more processors; and a memory, the memory storing instructions, which when executed by the one or more processors, cause the one or more processors to: receive an image patch of a target document; determine, from the received image patch, a query that indicates a two-dimensional geometric relationship between document features in the target document, the two-dimensional geometric relationship including an indication that the document features in the target document are a horizontally adjacent pair of document features or a vertically adjacent pair of document features; compare the query to an index table of the document features from mixed media documents to identify candidate regions in the mixed media documents that comprise the query, the index table comprising locations of the document features in the mixed media documents; and responsive to comparing the query to the document features in the index table, identify one or more of the mixed media documents comprising the identified candidate regions comprising the query by: adding a weight to an array of an accumulator for each cell in a zone around each pair of document features based on an inverse document frequency associated with each pair of document features, the inverse document frequency being inversely proportional to a number of document pages that contain the image patch; searching the array of the accumulator for the cell with a maximum value; and in response to the maximum value exceeding a threshold, reporting coordinates of the cell as a location of the image patch. 15. The system of claim 13 , wherein the instructions further cause the one or more processors to: locate a stored page as a candidate match for the image patch of the target document; and calculate the location within the stored page as a candidate center of the image patch.