display: add color balance properties.

Add support for hue, saturation, brightness and contrast attributes.

gst-libs/gst/vaapi/gstvaapidisplay.c

@@ -65,6 +65,10 @@ enum {
     PROP_HEIGHT,
     PROP_RENDER_MODE,
     PROP_ROTATION,
+    PROP_HUE,
+    PROP_SATURATION,
+    PROP_BRIGHTNESS,
+    PROP_CONTRAST,
 
     N_PROPERTIES
 };
@@ -79,6 +83,12 @@ get_attribute(GstVaapiDisplay *display, VADisplayAttribType type, gint *value);
 static gboolean
 set_attribute(GstVaapiDisplay *display, VADisplayAttribType type, gint value);
 
+static gboolean
+get_color_balance(GstVaapiDisplay *display, guint prop_id, gfloat *v);
+
+static gboolean
+set_color_balance(GstVaapiDisplay *display, guint prop_id, gfloat v);
+
 static inline GstVaapiDisplayCache *
 get_display_cache(void)
 {
@@ -361,6 +371,12 @@ find_property_by_type(GArray *properties, VADisplayAttribType type)
 }
 #endif
 
+static inline const GstVaapiProperty *
+find_property_by_pspec(GstVaapiDisplay *display, GParamSpec *pspec)
+{
+    return find_property(display->priv->properties, pspec->name);
+}
+
 static void
 gst_vaapi_display_calculate_pixel_aspect_ratio(GstVaapiDisplay *display)
 {
@@ -608,6 +624,18 @@ gst_vaapi_display_create(GstVaapiDisplay *display)
         case VADisplayAttribRotation:
             prop.name = GST_VAAPI_DISPLAY_PROP_ROTATION;
             break;
+        case VADisplayAttribHue:
+            prop.name = GST_VAAPI_DISPLAY_PROP_HUE;
+            break;
+        case VADisplayAttribSaturation:
+            prop.name = GST_VAAPI_DISPLAY_PROP_SATURATION;
+            break;
+        case VADisplayAttribBrightness:
+            prop.name = GST_VAAPI_DISPLAY_PROP_BRIGHTNESS;
+            break;
+        case VADisplayAttribContrast:
+            prop.name = GST_VAAPI_DISPLAY_PROP_CONTRAST;
+            break;
         default:
             prop.name = NULL;
             break;
@@ -732,6 +760,12 @@ gst_vaapi_display_set_property(
     case PROP_ROTATION:
         gst_vaapi_display_set_rotation(display, g_value_get_enum(value));
         break;
+    case PROP_HUE:
+    case PROP_SATURATION:
+    case PROP_BRIGHTNESS:
+    case PROP_CONTRAST:
+        set_color_balance(display, prop_id, g_value_get_float(value));
+        break;
     default:
         G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
         break;
@@ -771,6 +805,16 @@ gst_vaapi_display_get_property(
     case PROP_ROTATION:
         g_value_set_enum(value, gst_vaapi_display_get_rotation(display));
         break;
+    case PROP_HUE:
+    case PROP_SATURATION:
+    case PROP_BRIGHTNESS:
+    case PROP_CONTRAST: {
+        gfloat v;
+        if (!get_color_balance(display, prop_id, &v))
+            v = G_PARAM_SPEC_FLOAT(pspec)->default_value;
+        g_value_set_float(value, v);
+        break;
+    }
     default:
         G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);
         break;
@@ -864,6 +908,58 @@ gst_vaapi_display_class_init(GstVaapiDisplayClass *klass)
                           DEFAULT_ROTATION,
                           G_PARAM_READWRITE);
 
+    /**
+     * GstVaapiDisplay:hue:
+     *
+     * The VA display hue, expressed as a float value. Range is -180.0
+     * to 180.0. Default value is 0.0 and represents no modification.
+     */
+    g_properties[PROP_HUE] =
+        g_param_spec_float(GST_VAAPI_DISPLAY_PROP_HUE,
+                           "hue",
+                           "The display hue value",
+                           -180.0, 180.0, 0.0,
+                           G_PARAM_READWRITE);
+
+    /**
+     * GstVaapiDisplay:saturation:
+     *
+     * The VA display saturation, expressed as a float value. Range is
+     * 0.0 to 2.0. Default value is 1.0 and represents no modification.
+     */
+    g_properties[PROP_SATURATION] =
+        g_param_spec_float(GST_VAAPI_DISPLAY_PROP_SATURATION,
+                           "saturation",
+                           "The display saturation value",
+                           0.0, 2.0, 1.0,
+                           G_PARAM_READWRITE);
+
+    /**
+     * GstVaapiDisplay:brightness:
+     *
+     * The VA display brightness, expressed as a float value. Range is
+     * -1.0 to 1.0. Default value is 0.0 and represents no modification.
+     */
+    g_properties[PROP_BRIGHTNESS] =
+        g_param_spec_float(GST_VAAPI_DISPLAY_PROP_BRIGHTNESS,
+                           "brightness",
+                           "The display brightness value",
+                           -1.0, 1.0, 0.0,
+                           G_PARAM_READWRITE);
+
+    /**
+     * GstVaapiDisplay:contrast:
+     *
+     * The VA display contrast, expressed as a float value. Range is
+     * 0.0 to 2.0. Default value is 1.0 and represents no modification.
+     */
+    g_properties[PROP_CONTRAST] =
+        g_param_spec_float(GST_VAAPI_DISPLAY_PROP_CONTRAST,
+                           "contrast",
+                           "The display contrast value",
+                           0.0, 2.0, 1.0,
+                           G_PARAM_READWRITE);
+
     g_object_class_install_properties(object_class, N_PROPERTIES, g_properties);
 }
 
@@ -1539,3 +1635,72 @@ gst_vaapi_display_set_rotation(
     g_object_notify_by_pspec(G_OBJECT(display), g_properties[PROP_ROTATION]);
     return TRUE;
 }
+
+/* Get color balance attributes */
+static gboolean
+get_color_balance(GstVaapiDisplay *display, guint prop_id, gfloat *v)
+{
+    GParamSpecFloat * const pspec = G_PARAM_SPEC_FLOAT(g_properties[prop_id]);
+    const GstVaapiProperty *prop;
+    const VADisplayAttribute *attr;
+    gfloat out_value;
+    gint value;
+
+    if (!pspec)
+        return FALSE;
+
+    prop = find_property_by_pspec(display, &pspec->parent_instance);
+    if (!prop)
+        return FALSE;
+    attr = &prop->attribute;
+
+    if (!get_attribute(display, attr->type, &value))
+        return FALSE;
+
+    /* Scale wrt. the medium ("default") value */
+    out_value = pspec->default_value;
+    if (value > attr->value)
+        out_value += ((gfloat)(value - attr->value) /
+                      (attr->max_value - attr->value) *
+                      (pspec->maximum - pspec->default_value));
+    else if (value < attr->value)
+        out_value -= ((gfloat)(attr->value - value) /
+                      (attr->value - attr->min_value) *
+                      (pspec->default_value - pspec->minimum));
+    *v = out_value;
+    return TRUE;
+}
+
+/* Set color balance attribute */
+static gboolean
+set_color_balance(GstVaapiDisplay *display, guint prop_id, gfloat v)
+{
+    GParamSpecFloat * const pspec = G_PARAM_SPEC_FLOAT(g_properties[prop_id]);
+    const GstVaapiProperty *prop;
+    const VADisplayAttribute *attr;
+    gint value;
+
+    if (!pspec)
+        return FALSE;
+
+    prop = find_property_by_pspec(display, &pspec->parent_instance);
+    if (!prop)
+        return FALSE;
+    attr = &prop->attribute;
+
+    /* Scale wrt. the medium ("default") value */
+    value = attr->value;
+    if (v > pspec->default_value)
+        value += ((v - pspec->default_value) /
+                  (pspec->maximum - pspec->default_value) *
+                  (attr->max_value - attr->value));
+    else if (v < pspec->default_value)
+        value -= ((pspec->default_value - v) /
+                  (pspec->default_value - pspec->minimum) *
+                  (attr->value - attr->min_value));
+    if (!set_attribute(display, attr->type, value))
+        return FALSE;
+
+    g_object_notify_by_pspec(G_OBJECT(display), g_properties[prop_id]);
+    return TRUE;
+}

gst-libs/gst/vaapi/gstvaapidisplay.h

@@ -100,9 +100,17 @@ struct _GstVaapiDisplayInfo {
  * GstVaapiDisplayProperties:
  * @GST_VAAPI_DISPLAY_PROP_RENDER_MODE: rendering mode (#GstVaapiRenderMode).
  * @GST_VAAPI_DISPLAY_PROP_ROTATION: rotation angle (#GstVaapiRotation).
+ * @GST_VAAPI_DISPLAY_PROP_HUE: hue (float: [-180 ; 180], default: 0).
+ * @GST_VAAPI_DISPLAY_PROP_SATURATION: saturation (float: [0 ; 2], default: 1).
+ * @GST_VAAPI_DISPLAY_PROP_BRIGHTNESS: brightness (float: [-1 ; 1], default: 0).
+ * @GST_VAAPI_DISPLAY_PROP_CONTRAST: contrast (float: [0 ; 2], default: 1).
  */
 #define GST_VAAPI_DISPLAY_PROP_RENDER_MODE      "render-mode"
 #define GST_VAAPI_DISPLAY_PROP_ROTATION         "rotation"
+#define GST_VAAPI_DISPLAY_PROP_HUE              "hue"
+#define GST_VAAPI_DISPLAY_PROP_SATURATION       "saturation"
+#define GST_VAAPI_DISPLAY_PROP_BRIGHTNESS       "brightness"
+#define GST_VAAPI_DISPLAY_PROP_CONTRAST         "contrast"
 
 /**
  * GstVaapiDisplay: