4. A computing device comprising: at least one processor; a memory including instructions operable to be executed by the at least one processor to perform a set of actions to configure the at least one processor to: identify a first region of an image; identify a second region of the image; extract first contextual features from the first region, the first contextual features relating to a context of the first region; process the extracted first contextual features using a first classifier to determine that the extracted first contextual features are consistent with image data comprising a glyph; determine that the first region contains a glyph; determine that the second region does not contain a glyph; and stop further processing of the second region in response to determining the second region does not contain a glyph; identify candidate locations of the first region, the candidate locations comprising a first candidate location having a first local pixel pattern; extract second contextual features from the first local pixel pattern; process, using a second classifier, the first local pixel pattern to determine a first feature descriptor, wherein the first feature descriptor is based on spatial relationships between the first local pixel pattern within the first region; process, using the second classifier, the first local pixel pattern to determine a second feature descriptor, wherein the second feature descriptor relates to content of the first candidate location; and determine that the first candidate location contains a glyph using the first feature descriptor and the second feature descriptor.
4. A computing device comprising: at least one processor; a memory including instructions operable to be executed by the at least one processor to perform a set of actions to configure the at least one processor to: identify a first region of an image; identify a second region of the image; extract first contextual features from the first region, the first contextual features relating to a context of the first region; process the extracted first contextual features using a first classifier to determine that the extracted first contextual features are consistent with image data comprising a glyph; determine that the first region contains a glyph; determine that the second region does not contain a glyph; and stop further processing of the second region in response to determining the second region does not contain a glyph; identify candidate locations of the first region, the candidate locations comprising a first candidate location having a first local pixel pattern; extract second contextual features from the first local pixel pattern; process, using a second classifier, the first local pixel pattern to determine a first feature descriptor, wherein the first feature descriptor is based on spatial relationships between the first local pixel pattern within the first region; process, using the second classifier, the first local pixel pattern to determine a second feature descriptor, wherein the second feature descriptor relates to content of the first candidate location; and determine that the first candidate location contains a glyph using the first feature descriptor and the second feature descriptor. 5. The computing device of claim 4 , wherein the instructions to determine the first feature descriptor include instructions to: extract features from the first region comprising gradient or intensity patterns; aggregate the extracted features; and quantize the aggregated extracted features as the first feature descriptor.