Detecting text that randomly appears in a scene is a problem that's harder than it looks. There are several new variables that you need to take into account when you're comparing to identified scanned text, such as the following:
- Tridimensionality: The text may be in any scale, orientation, or perspective. Also, the text may be partially occluded or interrupted. There are literally thousands of possible regions where it may appear in the image.
- Variety: Text can be in several different fonts and colors. The font may have outline borders. The background can be dark, light, or a complex image.
- Illumination and shadows: The sunlight's position and apparent color changes over time. Different weather conditions like ...