public static final int RAW12 = 0x26;
/**
- * Android dense depth image format.
- *
- * Each pixel is 16 bits, representing a depth ranging measurement from
- * a depth camera or similar sensor.
+ * <p>Android dense depth image format.</p>
+ *
+ * <p>Each pixel is 16 bits, representing a depth ranging measurement from a depth camera or
+ * similar sensor. The 16-bit sample consists of a confidence value and the actual ranging
+ * measurement.</p>
+ *
+ * <p>The confidence value is an estimate of correctness for this sample. It is encoded in the
+ * 3 most significant bits of the sample, with a value of 0 representing 100% confidence, a
+ * value of 1 representing 0% confidence, a value of 2 representing 1/7, a value of 3
+ * representing 2/7, and so on.</p>
+ *
+ * <p>As an example, the following sample extracts the range and confidence from the first pixel
+ * of a DEPTH16-format {@link android.media.Image}, and converts the confidence to a
+ * floating-point value between 0 and 1.f inclusive, with 1.f representing maximum confidence:
+ *
+ * <pre>
+ * ShortBuffer shortDepthBuffer = img.getPlanes()[0].getBuffer().asShortBuffer();
+ * short depthSample = shortDepthBuffer.get()
+ * short depthRange = (short) (depthSample & 0x1FFF);
+ * short depthConfidence = (short) ((depthSample >> 13) & 0x7);
+ * float depthPercentage = depthConfidence == 0 ? 1.f : (depthConfidence - 1) / 7.f;
+ * </pre>
+ * </p>
*
* <p>This format assumes
* <ul>
*
* <pre> y_size = stride * height </pre>
*
- * When produced by a camera, the units are millimeters.
+ * When produced by a camera, the units for the range are millimeters.
*/
public static final int DEPTH16 = 0x44363159;
/**
* Android sparse depth point cloud format.
*
- * <p>A variable-length list of 3D points, with each point represented
- * by a triple of floats.</p>
+ * <p>A variable-length list of 3D points plus a confidence value, with each point represented
+ * by four floats; first the X, Y, Z position coordinates, and then the confidence value.</p>
+ *
+ * <p>The number of points is {@code (size of the buffer in bytes) / 16}.
+ *
+ * <p>The coordinate system and units of the position values depend on the source of the point
+ * cloud data. The confidence value is between 0.f and 1.f, inclusive, with 0 representing 0%
+ * confidence and 1.f representing 100% confidence in the measured position values.</p>
*
- * <p>The number of points is {@code (size of the buffer in bytes) / 12}.
+ * <p>As an example, the following code extracts the first depth point in a DEPTH_POINT_CLOUD
+ * format {@link android.media.Image}:
+ * <pre>
+ * FloatBuffer floatDepthBuffer = img.getPlanes()[0].getBuffer().asFloatBuffer();
+ * float x = floatDepthBuffer.get();
+ * float y = floatDepthBuffer.get();
+ * float z = floatDepthBuffer.get();
+ * float confidence = floatDepthBuffer.get();
+ * </pre>
*
- * The coordinate system and units depend on the source of the point cloud data.
*/
public static final int DEPTH_POINT_CLOUD = 0x101;