IHPDFFaceDetector Interface

function Detect(
    const Request: THPDFFaceDetectionRequest;
    out Results: THPDFFaceDetectorResults;
    out Diagnostic: AnsiString): boolean;

Detect receives a bounded 24-bit rendered bitmap and returns top-left-origin pixel rectangles with confidence values

The detector executes synchronously, must honor MaxResults and cancellation, and must not retain Bitmap after the call

HotPDF validates every rectangle and reverses page rotation and device scaling into PDF page user space