This interface is implemented by elements which can perform some color balance operation on video frames they process. For example, modifying the brightness, contrast, hue or saturation.

Example elements are 'xvimagesink' and 'colorbalance'

gst_color_balance_list_channels ()

const GList *
gst_color_balance_list_channels (GstColorBalance *balance);

Retrieve a list of the available channels.

gst_color_balance_get_value ()

gint
gst_color_balance_get_value (GstColorBalance *balance,
                             GstColorBalanceChannel *channel);

Retrieve the current value of the indicated channel, between min_value and max_value.

See Also: The GstColorBalanceChannel.min_value and GstColorBalanceChannel.max_value members of the GstColorBalanceChannel object.

gst_color_balance_set_value ()

void
gst_color_balance_set_value (GstColorBalance *balance,
                             GstColorBalanceChannel *channel,
                             gint value);

Sets the current value of the channel to the passed value, which must be between min_value and max_value.

See Also: The GstColorBalanceChannel.min_value and GstColorBalanceChannel.max_value members of the GstColorBalanceChannel object.

gst_color_balance_value_changed ()

void
gst_color_balance_value_changed (GstColorBalance *balance,
                                 GstColorBalanceChannel *channel,
                                 gint value);

A helper function called by implementations of the GstColorBalance interface. It fires the “value-changed” signal on the instance, and the “value-changed” signal on the channel object.

gst_color_balance_get_balance_type ()

GstColorBalanceType
gst_color_balance_get_balance_type (GstColorBalance *balance);

Get the GstColorBalanceType of this implementation.

GstColorBalance

typedef struct _GstColorBalance GstColorBalance;

struct GstColorBalanceInterface

struct GstColorBalanceInterface {
  GTypeInterface iface;

  /* virtual functions */
  const GList * (* list_channels) (GstColorBalance        *balance);

  void          (* set_value)     (GstColorBalance        *balance,
                                   GstColorBalanceChannel *channel,
                                   gint                    value);
  gint          (* get_value)     (GstColorBalance        *balance,
                                   GstColorBalanceChannel *channel);
  GstColorBalanceType (*get_balance_type)  (GstColorBalance *balance);

  /* signals */
  void (* value_changed) (GstColorBalance        *balance,
                          GstColorBalanceChannel *channel,
                          gint                    value);
};

Color-balance interface.

enum GstColorBalanceType

An enumeration indicating whether an element implements color balancing operations in software or in dedicated hardware. In general, dedicated hardware implementations (such as those provided by xvimagesink) are preferred.

The “value-changed” signal

void
user_function (GstColorBalance        *colorbalance,
               GstColorBalanceChannel *channel,
               gint                    value,
               gpointer                user_data)

Fired when the value of the indicated channel has changed.

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