video-color: Add bt601 transfer function

Functionally the same as 709 but technically has a different value, and external software (e.g. ffmpeg) finds "wrong" values produced by GStreamer. Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/724>
2024-06-18 05:50:41 +00:00 · 2020-06-25 20:56:48 +03:00 · 2020-06-25 20:56:48 +03:00 · 1d0ccf8baa
parent 2d70ff5ef0
commit 1d0ccf8baa
4 changed files with 52 additions and 25 deletions
--- a/gst-libs/gst/video/video-color.c
+++ b/gst-libs/gst/video/video-color.c
@ -64,7 +64,7 @@ typedef struct
 #define GST_VIDEO_COLORIMETRY_NONAME  NULL

 static const ColorimetryInfo colorimetry[] = {
-  MAKE_COLORIMETRY (BT601, _16_235, BT601, BT709, SMPTE170M),
+  MAKE_COLORIMETRY (BT601, _16_235, BT601, BT601, SMPTE170M),
  MAKE_COLORIMETRY (BT709, _16_235, BT709, BT709, BT709),
  MAKE_COLORIMETRY (SMPTE240M, _16_235, SMPTE240M, SMPTE240M, SMPTE240M),
  MAKE_COLORIMETRY (SRGB, _0_255, RGB, SRGB, BT709),
@ -435,6 +435,7 @@ gst_video_color_transfer_encode (GstVideoTransferFunction func, gdouble val)
    case GST_VIDEO_TRANSFER_GAMMA22:
      res = pow (val, 1.0 / 2.2);
      break;
+    case GST_VIDEO_TRANSFER_BT601:
    case GST_VIDEO_TRANSFER_BT709:
    case GST_VIDEO_TRANSFER_BT2020_10:
      if (val < 0.018)
@ -552,6 +553,7 @@ gst_video_color_transfer_decode (GstVideoTransferFunction func, gdouble val)
    case GST_VIDEO_TRANSFER_GAMMA22:
      res = pow (val, 2.2);
      break;
+    case GST_VIDEO_TRANSFER_BT601:
    case GST_VIDEO_TRANSFER_BT709:
    case GST_VIDEO_TRANSFER_BT2020_10:
      if (val < 0.081)
@ -689,6 +691,8 @@ gst_video_color_transfer_to_iso (GstVideoTransferFunction func)
      return 4;
    case GST_VIDEO_TRANSFER_GAMMA28:
      return 5;
+    case GST_VIDEO_TRANSFER_BT601:
+      return 6;
    case GST_VIDEO_TRANSFER_SMPTE240M:
      return 7;
    case GST_VIDEO_TRANSFER_GAMMA10:
@ -818,12 +822,13 @@ gst_video_color_transfer_from_iso (guint value)
 {
  switch (value) {
    case 1:
-    case 6:
      return GST_VIDEO_TRANSFER_BT709;
    case 4:
      return GST_VIDEO_TRANSFER_GAMMA22;
    case 5:
      return GST_VIDEO_TRANSFER_GAMMA28;
+    case 6:
+      return GST_VIDEO_TRANSFER_BT601;
    case 7:
      return GST_VIDEO_TRANSFER_SMPTE240M;
    case 8:
--- a/gst-libs/gst/video/video-color.h
+++ b/gst-libs/gst/video/video-color.h
@ -45,10 +45,12 @@ typedef enum {
 /**
 * GstVideoColorMatrix:
 * @GST_VIDEO_COLOR_MATRIX_UNKNOWN: unknown matrix
- * @GST_VIDEO_COLOR_MATRIX_RGB: identity matrix
- * @GST_VIDEO_COLOR_MATRIX_FCC: FCC color matrix
- * @GST_VIDEO_COLOR_MATRIX_BT709: ITU-R BT.709 color matrix
- * @GST_VIDEO_COLOR_MATRIX_BT601: ITU-R BT.601 color matrix
+ * @GST_VIDEO_COLOR_MATRIX_RGB: identity matrix. Order of coefficients is
+ * actually GBR, also IEC 61966-2-1 (sRGB)
+ * @GST_VIDEO_COLOR_MATRIX_FCC: FCC Title 47 Code of Federal Regulations 73.682 (a)(20)
+ * @GST_VIDEO_COLOR_MATRIX_BT709: ITU-R BT.709 color matrix, also ITU-R BT1361
+ * / IEC 61966-2-4 xvYCC709 / SMPTE RP177 Annex B
+ * @GST_VIDEO_COLOR_MATRIX_BT601: ITU-R BT.601 color matrix, also SMPTE170M / ITU-R BT1358 525 / ITU-R BT1700 NTSC
 * @GST_VIDEO_COLOR_MATRIX_SMPTE240M: SMPTE 240M color matrix
 * @GST_VIDEO_COLOR_MATRIX_BT2020: ITU-R BT.2020 color matrix. Since: 1.6
 *
@ -76,23 +78,24 @@ gboolean gst_video_color_matrix_get_Kr_Kb (GstVideoColorMatrix matrix, gdouble *
 * @GST_VIDEO_TRANSFER_GAMMA20: Gamma 2.0 curve
 * @GST_VIDEO_TRANSFER_GAMMA22: Gamma 2.2 curve
 * @GST_VIDEO_TRANSFER_BT709: Gamma 2.2 curve with a linear segment in the lower
- *                           range
+ *                           range, also ITU-R BT470M / ITU-R BT1700 625 PAL &
+ *                           SECAM / ITU-R BT1361
 * @GST_VIDEO_TRANSFER_SMPTE240M: Gamma 2.2 curve with a linear segment in the
 *                               lower range
 * @GST_VIDEO_TRANSFER_SRGB: Gamma 2.4 curve with a linear segment in the lower
- *                          range
- * @GST_VIDEO_TRANSFER_GAMMA28: Gamma 2.8 curve
+ *                          range. IEC 61966-2-1 (sRGB or sYCC)
+ * @GST_VIDEO_TRANSFER_GAMMA28: Gamma 2.8 curve, also ITU-R BT470BG
 * @GST_VIDEO_TRANSFER_LOG100: Logarithmic transfer characteristic
 *                             100:1 range
 * @GST_VIDEO_TRANSFER_LOG316: Logarithmic transfer characteristic
- *                             316.22777:1 range
+ *                             316.22777:1 range (100 * sqrt(10) : 1)
 * @GST_VIDEO_TRANSFER_BT2020_12: Gamma 2.2 curve with a linear segment in the lower
 *                                range. Used for BT.2020 with 12 bits per
 *                                component. Since: 1.6
 * @GST_VIDEO_TRANSFER_ADOBERGB: Gamma 2.19921875. Since: 1.8
 * @GST_VIDEO_TRANSFER_BT2020_10: Rec. ITU-R BT.2020-2 with 10 bits per component.
 *                                (functionally the same as the values
- *                                GST_VIDEO_TRANSFER_BT709 and GST_VIDEO_TRANSFER_BT2020_12).
+ *                                GST_VIDEO_TRANSFER_BT709 and GST_VIDEO_TRANSFER_BT601).
 *                                Since: 1.18
 * @GST_VIDEO_TRANSFER_SMPTE2084: SMPTE ST 2084 for 10, 12, 14, and 16-bit systems.
 *                                Known as perceptual quantization (PQ)
@ -100,6 +103,10 @@ gboolean gst_video_color_matrix_get_Kr_Kb (GstVideoColorMatrix matrix, gdouble *
 * @GST_VIDEO_TRANSFER_ARIB_STD_B67: Association of Radio Industries and Businesses (ARIB)
 *                                   STD-B67 and Rec. ITU-R BT.2100-1 hybrid loggamma (HLG) system
 *                                   Since: 1.18
+ * @GST_VIDEO_TRANSFER_BT601: also known as SMPTE170M / ITU-R BT1358 525 or 625 / ITU-R BT1700 NTSC
+ *                            Functionally the same as the values
+ *                            GST_VIDEO_TRANSFER_BT709, and GST_VIDEO_TRANSFER_BT2020_10.
+ *                            Since: 1.18
 *
 * The video transfer function defines the formula for converting between
 * non-linear RGB (R'G'B') and linear RGB
@ -120,7 +127,13 @@ typedef enum {
  GST_VIDEO_TRANSFER_ADOBERGB,
  GST_VIDEO_TRANSFER_BT2020_10,
  GST_VIDEO_TRANSFER_SMPTE2084,
-  GST_VIDEO_TRANSFER_ARIB_STD_B67
+  GST_VIDEO_TRANSFER_ARIB_STD_B67,
+  /**
+   * GST_VIDEO_TRANSFER_BT601:
+   * also known as SMPTE170M / ITU-R BT1358 525 or 625 / ITU-R BT1700 NTSC
+   * Since: 1.18
+   */
+  GST_VIDEO_TRANSFER_BT601
 } GstVideoTransferFunction;

 GST_VIDEO_API
@ -132,18 +145,27 @@ gdouble      gst_video_color_transfer_decode (GstVideoTransferFunction func, gdo
 /**
 * GstVideoColorPrimaries:
 * @GST_VIDEO_COLOR_PRIMARIES_UNKNOWN: unknown color primaries
- * @GST_VIDEO_COLOR_PRIMARIES_BT709: BT709 primaries
- * @GST_VIDEO_COLOR_PRIMARIES_BT470M: BT470M primaries
- * @GST_VIDEO_COLOR_PRIMARIES_BT470BG: BT470BG primaries
- * @GST_VIDEO_COLOR_PRIMARIES_SMPTE170M: SMPTE170M primaries
+ * @GST_VIDEO_COLOR_PRIMARIES_BT709: BT709 primaries, also ITU-R BT1361 / IEC
+ * 61966-2-4 / SMPTE RP177 Annex B
+ * @GST_VIDEO_COLOR_PRIMARIES_BT470M: BT470M primaries, also FCC Title 47 Code
+ * of Federal Regulations 73.682 (a)(20)
+ * @GST_VIDEO_COLOR_PRIMARIES_BT470BG: BT470BG primaries, also ITU-R BT601-6
+ * 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM
+ * @GST_VIDEO_COLOR_PRIMARIES_SMPTE170M: SMPTE170M primaries, also ITU-R
+ * BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC
 * @GST_VIDEO_COLOR_PRIMARIES_SMPTE240M: SMPTE240M primaries
- * @GST_VIDEO_COLOR_PRIMARIES_FILM: Generic film
- * @GST_VIDEO_COLOR_PRIMARIES_BT2020: BT2020 primaries. Since: 1.6
+ * @GST_VIDEO_COLOR_PRIMARIES_FILM: Generic film (colour filters using
+ * Illuminant C)
+ * @GST_VIDEO_COLOR_PRIMARIES_BT2020: ITU-R BT2020 primaries. Since: 1.6
 * @GST_VIDEO_COLOR_PRIMARIES_ADOBERGB: Adobe RGB primaries. Since: 1.8
- * @GST_VIDEO_COLOR_PRIMARIES_SMPTEST428: SMPTE ST 428 primaries. Since: 1.16
- * @GST_VIDEO_COLOR_PRIMARIES_SMPTERP431: SMPTE RP 431 primaries. Since: 1.16
- * @GST_VIDEO_COLOR_PRIMARIES_SMPTEEG432: SMPTE EG 432 primaries. Since: 1.16
- * @GST_VIDEO_COLOR_PRIMARIES_EBU3213: EBU 3213 primaries. Since: 1.16
+ * @GST_VIDEO_COLOR_PRIMARIES_SMPTEST428: SMPTE ST 428 primaries (CIE 1931
+ * XYZ). Since: 1.16
+ * @GST_VIDEO_COLOR_PRIMARIES_SMPTERP431: SMPTE RP 431 primaries (ST 431-2
+ * (2011) / DCI P3). Since: 1.16
+ * @GST_VIDEO_COLOR_PRIMARIES_SMPTEEG432: SMPTE EG 432 primaries (ST 432-1
+ * (2010) / P3 D65). Since: 1.16
+ * @GST_VIDEO_COLOR_PRIMARIES_EBU3213: EBU 3213 primaries (JEDEC P22
+ * phosphors). Since: 1.16
 *
 * The color primaries define the how to transform linear RGB values to and from
 * the CIE XYZ colorspace.
--- a/gst-libs/gst/video/video-info.c
+++ b/gst-libs/gst/video/video-info.c
@ -153,7 +153,7 @@ gst_video_info_init (GstVideoInfo * info)
 #define DEFAULT_YUV_UHD 5

 static const GstVideoColorimetry default_color[] = {
-  MAKE_COLORIMETRY (_16_235, BT601, BT709, SMPTE170M),
+  MAKE_COLORIMETRY (_16_235, BT601, BT601, SMPTE170M),
  MAKE_COLORIMETRY (_16_235, BT709, BT709, BT709),
  MAKE_COLORIMETRY (_0_255, RGB, SRGB, BT709),
  MAKE_COLORIMETRY (_0_255, BT601, UNKNOWN, UNKNOWN),
--- a/tests/check/libs/video.c
+++ b/tests/check/libs/video.c
@ -948,8 +948,8 @@ GST_START_TEST (test_parse_colorimetry)
 {
  ColorimetryTest tests[] = {
    MAKE_COLORIMETRY_TEST ("bt601", "bt601", "bt601",
-        _16_235, BT601, BT709, SMPTE170M),
-    MAKE_COLORIMETRY_TEST ("2:4:5:4", "bt601", "bt601",
+        _16_235, BT601, BT601, SMPTE170M),
+    MAKE_COLORIMETRY_TEST ("2:4:5:4", "2:4:5:4", NULL,
        _16_235, BT601, BT709, SMPTE170M),
    MAKE_COLORIMETRY_TEST ("bt709", "bt709", "bt709",
        _16_235, BT709, BT709, BT709),