};
/**
- * MPEG vs JPEG YUV range.
+ * Visual content value range.
+ *
+ * These values are based on definitions that can be found in multiple
+ * specifications, such as ITU-T BT.709 (3.4 - Quantization of RGB, luminance
+ * and colour-difference signals), ITU-T BT.2020 (Table 5 - Digital
+ * Representation) as well as ITU-T BT.2100 (Table 9 - Digital 10- and 12-bit
+ * integer representation). At the time of writing, the BT.2100 one is
+ * recommended, as it also defines the full range representation.
+ *
+ * Common definitions:
+ * - For RGB and luminance planes such as Y in YCbCr and I in ICtCp,
+ * 'E' is the original value in range of 0.0 to 1.0.
+ * - For chrominance planes such as Cb,Cr and Ct,Cp, 'E' is the original
+ * value in range of -0.5 to 0.5.
+ * - 'n' is the output bit depth.
+ * - For additional definitions such as rounding and clipping to valid n
+ * bit unsigned integer range, please refer to BT.2100 (Table 9).
*/
enum AVColorRange {
AVCOL_RANGE_UNSPECIFIED = 0,
- AVCOL_RANGE_MPEG = 1, ///< the normal 219*2^(n-8) "MPEG" YUV ranges
- AVCOL_RANGE_JPEG = 2, ///< the normal 2^n-1 "JPEG" YUV ranges
+
+ /**
+ * Narrow or limited range content.
+ *
+ * - For luminance planes:
+ *
+ * (219 * E + 16) * 2^(n-8)
+ *
+ * F.ex. the range of 16-235 for 8 bits
+ *
+ * - For chrominance planes:
+ *
+ * (224 * E + 128) * 2^(n-8)
+ *
+ * F.ex. the range of 16-240 for 8 bits
+ */
+ AVCOL_RANGE_MPEG = 1,
+
+ /**
+ * Full range content.
+ *
+ * - For RGB and luminance planes:
+ *
+ * (2^n - 1) * E
+ *
+ * F.ex. the range of 0-255 for 8 bits
+ *
+ * - For chrominance planes:
+ *
+ * (2^n - 1) * E + 2^(n - 1)
+ *
+ * F.ex. the range of 1-255 for 8 bits
+ */
+ AVCOL_RANGE_JPEG = 2,
AVCOL_RANGE_NB ///< Not part of ABI
};