Image format

  • Liveness API supports BMP, JPEG, JPEG2000, PNG, WebP and TIFF formats.

  • Lossless formats are preferred, as lossy compression can have a negative effect on the accuracy. If you use lossy formats make sure the compression is at minimal level. For example for the JPEG the 70 is the lowest practical compression level.

Image composition

  • There should only be one main face on the image. It should be fully visible within a frame and fully open without any occlusions. No crop is allowed. Small faces in the background are not taken into account.

  • The minimum size of a face box that can be processed is 224x224 pixels.

  • The padding between the face box and the image's borders should be at least 25 pixels.

  • The distance between the pupils on the face should be at least 80 pixels.

  • The out-of-plane rotation angle (face pitch and yaw) should be no more than ±30 degrees.

Images that do not match these conditions will be rejected. Other conditions can affect the accuracy:

  • Motion blur effect can significantly increase BPCER (the rate of errors classifying a live person as a spoof).

  • Texture filtering can significantly increase APCER (the rate of errors allowing impostors through).

  • Spotlights on the faces and nearest surroundings can significantly increase BPCER.

  • Ill-lighted environments and colored light can significantly increase BPCER.

  • Fish-eye lenses are not supported.

  • Sunglasses may cause confusion