Image quality requirements

Below are the requirements for size and quality of document images captured by any device, which are necessary for successful image processing by Document Reader SDK Web API:

1.Good lighting

Environment with good lighting helps with recognizing the characters in the image. When the image is too dark or too bright the document can not be validated.

2.Avoid reflections

Don’t use flashlight on your device. Avoid reflections from lamps or environmental lights. 

Reflections on the image interfere with the processing and extracting the data. 

3.Focus and sharpness

Make sure the image is clear and there are no blurred areas.

4.Angle

The tilt angle of the document should not exceed 10 degrees in any direction (horizontal or vertical).

5.Margins (too close)

Make sure there’s minimum space around the document. Don’t zoom the image. It is recommended that the document takes up 70-80% of the image.

6.Margins (too far)

Make sure the space around the document is not taking more than 20-30% of the image It is recommended that the document takes up 70-80% of the image.

7.Contrast

The document should be in clear contrast to the background. A light-colored document on a light background, as well as a dark-colored document on a dark background, cannot be recognized.

8.Resolution of the image

To achieve good quality of recognition of identification documents, we recommend that you provide images captured by camera with a resolution of at least Full HD (1920×1080) and autofocus.

9.Subjection

Make sure your hands or other objects don’t cover document data.