![]() Images synced by Premium users, however, are moved to the front of the queue ahead of all images synced by free users.Īs to how long it will take, this depends on the size of the queue when the image is sent for processing. The system is queue-based, meaning the submitted image takes its place in line and will be processed after all other images ahead of it in the queue. When a user syncs a note containing an image, the image is sent to the aforementioned group of servers for OCR processing. ![]() How long does it take for an image to be processed by OCR? Rather, there will usually be several potential matches for a given rectangle containing text and many of them will be inexact. As described before, the matching done by the OCR system doesn’t produce one-to-one matches. That said, the OCR engine is being constantly refined and tuned for better accuracy.Ĭan Evernote’s OCR be used to create a text version of an image that contains text? It’s important to remember that no OCR system is perfect and it’s possible that text you expect to be recognized may not be. Text that does not match one of these orientations will be ignored (including diagonal and inverted text). Text found within an image will be evaluated if it matches one of the following orientations within a few degrees: The orientation of the text is a factor, as well. Typewritten text (e.g., street signs or posters) and handwritten notes (even if your handwriting isn’t the neatest in the world) are both evaluated by the OCR service, provided the service can detect them. Common questionsĪnything that the OCR system believes to be text. The data node contains a base–64 encoded version of the original PDF and the alternative-data represents the searchable version of the same PDF. If you export a note containing a PDF that has been processed by the OCR system, there will be two nodes in the document: data and alternate-data. If the scanner software performs its own OCR on the PDF, it won’t be processed by Evernote’s OCR service. PDFs that are generated by hardware scanners generally meet the above requirements. In practical terms, this eliminates many PDFs generated by other applications from text-based formats, such as word processors and other authoring applications. It must not contain selectable text (or, at least, a minimal amount).It also doesn’t count against the user’s monthly upload allowance.įor a PDF to be eligible for OCR, it must meet certain requirements: ![]() This second PDF is not visible to the user and exists only to facilitate search. When a PDF is processed, a second PDF document that contains the recognized text is created and embedded in the note containing the original PDF. When a user issues a search within an Evernote client, the content of the t elements is searched: How PDFs are processedĮvernote’s OCR system can also process PDF files, but they’re handled differently from images. You’ll notice that most of the item elements have multiple t elements and each is assigned the weight value we described earlier. ![]() Here’s a portion of the recoIndex element found in the note shown earlier which contains item and t (match) elements. At this point, the text found in the image is available for search. The OCR results are embedded in the note, which is subsequently synchronized back to the user’s client applications. Each match is assigned a weight (represented by the w attribute of the item): a numeric value indicating the likelihood that the given match text is the same as the text in the image. Each item represents a rectangle Evernote’s OCR system believes to contain text.Įach item contains four attributes: x and y indicating the coordinates of top-left corner of the area represented by the item, as well as w and h representing the width and height of the item.Īs an image is evaluated for textual content, a set of possible matches is created as child elements to their corresponding item. Contained within recoIndex are a number of item nodes. When I export this note as an ENEX file-a portable XML export format for Evernote notes-and jump to the bottom of the file, I’ll find the recoIndex element. The full recoIndex node is visible when a note is exported as an ENEX file.įor example, I dug around and found an old note in my account containing only a single photo of a bottle of beer: These results are added to the note in the form of a hidden-that is, not visible when viewing the note-metadata attribute called recoIndex. When a note is sent to Evernote (via synchronization), any Resources included in the note that match the MIME types for PNG, JPG or GIF are sent to a different set of servers whose sole job is performing Optical Character Recognition (OCR) on the supplied image and report back with whatever it finds. In this post, I’ll describe how the process works and answer some frequently-asked questions. Evernote’s ability to search for text within images is a popular feature. ![]()
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