Detect human faces in an image and returns face locations, and optionally with faceIds, landmarks, and attributes. <ul> <li>Optional parameters for returning faceId, landmarks, and attributes. Attributes include age, gender, smile intensity, facial hair, head pose and glasses. faceId is for other APIs use including <a href="/docs/services/563879b61984550e40cbbe8d/operations/563879b61984550f30395239">Face - Identify</a>, <a href="/docs/services/563879b61984550e40cbbe8d/operations/563879b61984550f3039523a">Face - Verify</a>, and <a href="/docs/services/563879b61984550e40cbbe8d/operations/563879b61984550f30395237">Face - Find Similar</a>. The faceId will expire in 24 hours after detection call.</li> <ul> <li>JPEG, PNG, GIF(the first frame), and BMP are supported. The image file size should be larger than or equal to 1KB but no larger than 4MB.</li> <li>The detectable face size is between 36x36 to 4096x4096 pixels. The faces out of this range will not be detected.</li> <li>A maximum of 64 faces could be returned for an image. The returned faces are ranked by face rectangle size in descending order.</li> <li>Some faces may not be detected for technical challenges, e.g. very large face angles (head-pose) or large occlusion. Frontal and near-frontal faces have the best results.</li> <li>Attributes (age, gender, headPose, smile, facialHair, and glasses) are still experimental and may not be very accurate. HeadPose's pitch value is a reserved field and will always return 0.</li> </ul> </li> </ul> <h4>Http Method</h4> POST