IMAGE UPLOAD SETTINGS
We may ask you to upload images of documents required to open your account. The following guidelines should help you to supply images in a satisfactory format.
For best performance we recommend that you scan the required documents. You can upload images in BMP, PNG, TIF and JPG formats.
The resolution of an image has a direct impact on the successful classification of a document. We strongly recommend using a minimum resolution of 600 DPI. The minimum pixel width and height is 350 x 350 pixels. If you resize an image, please ensure you keep the same aspect ratio.
If you have an image with a resolution greater than 800 DPI, it should be scaled down in size and resolution before compression to optimise processing performance. The horizontal and vertical resolution of the image should ideally be within 1% of each other.
Compression and cropping
Please do not excessively compress an image. Over-compression may degrade data capture and authentication performance.
For image cropping, please use ‘None’ if the images are already tightly cropped, or ‘Always’ if the images are uncropped. We recommend that you only use ‘Automatic’ as a last resort. Images should be cropped to the edges of the required identification document, but no further. Over-cropped images may not be successfully processed.
A sharpness score of 0 means that the image is very blurry and a score of 100 means that the image is very sharp. We recommend a sharpness metric equal to or greater than 50, and images below this score may not be successfully processed.
Similarly, a glare score of 0 means the image has poor light uniformity and a score of 100 means that the image contains no glare. We recommend a glare metric of at least 50 for successful processing.
Processing of facial images may be impaired by a motion blur effect, texture filtering, a spotlight on the face, an environment with poor lighting or coloured light, or use of a fish-eye lens.
Physical versus effective resolution
Two images with the same physical resolution can have dramatically different effective resolutions, due to factors such as focus, optics, compression and image processing. The effective resolution is always less than or equal to the physical resolution. Mobile and other ‘camera-based’ devices will produce a much lower effective-to-physical resolution ratio than scanners.
Accurate physical resolution is required to find regions of interest (ROIs) within the document, relative to other objects. Identity documents rely on these high-frequency (resolution) features, such as microtext, fine line patterns and dot patterns, to protect against counterfeiting.
Even regions within an image can have a different effective resolution, and this can impair image processing and authentication.