gstreamer/ext/pango/gsttextoverlay.h
Mark Nauwelaerts 90a79b4c60 textoverlay: configurable text color and position
Rather than only left, right, top, etc, allow for horizontal and vertical
positioning on a scale from 0 to 1.
Also cater for configuring rendered text color.

Fixes #624920.

API: GstTextOverlay:xpos
API: GstTextOverlay:ypos
API: GstTextOverlay:color
2010-08-09 09:49:12 +02:00

164 lines
5.4 KiB
C

#ifndef __GST_TEXT_OVERLAY_H__
#define __GST_TEXT_OVERLAY_H__
#include <gst/gst.h>
#include <gst/video/video.h>
#include <pango/pangocairo.h>
G_BEGIN_DECLS
#define GST_TYPE_TEXT_OVERLAY (gst_text_overlay_get_type())
#define GST_TEXT_OVERLAY(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),\
GST_TYPE_TEXT_OVERLAY, GstTextOverlay))
#define GST_TEXT_OVERLAY_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),\
GST_TYPE_TEXT_OVERLAY,GstTextOverlayClass))
#define GST_TEXT_OVERLAY_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),\
GST_TYPE_TEXT_OVERLAY, GstTextOverlayClass))
#define GST_IS_TEXT_OVERLAY(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),\
GST_TYPE_TEXT_OVERLAY))
#define GST_IS_TEXT_OVERLAY_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),\
GST_TYPE_TEXT_OVERLAY))
typedef struct _GstTextOverlay GstTextOverlay;
typedef struct _GstTextOverlayClass GstTextOverlayClass;
/**
* GstTextOverlayVAlign:
* @GST_TEXT_OVERLAY_VALIGN_BASELINE: draw text on the baseline
* @GST_TEXT_OVERLAY_VALIGN_BOTTOM: draw text on the bottom
* @GST_TEXT_OVERLAY_VALIGN_TOP: draw test on top
*
* Vertical alignment of the text.
*/
typedef enum {
GST_TEXT_OVERLAY_VALIGN_BASELINE,
GST_TEXT_OVERLAY_VALIGN_BOTTOM,
GST_TEXT_OVERLAY_VALIGN_TOP,
GST_TEXT_OVERLAY_VALIGN_POS
} GstTextOverlayVAlign;
/**
* GstTextOverlayHAlign:
* @GST_TEXT_OVERLAY_HALIGN_LEFT: align text left
* @GST_TEXT_OVERLAY_HALIGN_CENTER: align text center
* @GST_TEXT_OVERLAY_HALIGN_RIGHT: align text right
*
* Horizontal alignment of the text.
*/
typedef enum {
GST_TEXT_OVERLAY_HALIGN_LEFT,
GST_TEXT_OVERLAY_HALIGN_CENTER,
GST_TEXT_OVERLAY_HALIGN_RIGHT,
GST_TEXT_OVERLAY_HALIGN_TOP,
GST_TEXT_OVERLAY_HALIGN_POS
} GstTextOverlayHAlign;
/**
* GstTextOverlayWrapMode:
* @GST_TEXT_OVERLAY_WRAP_MODE_NONE: no wrapping
* @GST_TEXT_OVERLAY_WRAP_MODE_WORD: do word wrapping
* @GST_TEXT_OVERLAY_WRAP_MODE_CHAR: do char wrapping
* @GST_TEXT_OVERLAY_WRAP_MODE_WORD_CHAR: do word and char wrapping
*
* Whether to wrap the text and if so how.
*/
typedef enum {
GST_TEXT_OVERLAY_WRAP_MODE_NONE = -1,
GST_TEXT_OVERLAY_WRAP_MODE_WORD = PANGO_WRAP_WORD,
GST_TEXT_OVERLAY_WRAP_MODE_CHAR = PANGO_WRAP_CHAR,
GST_TEXT_OVERLAY_WRAP_MODE_WORD_CHAR = PANGO_WRAP_WORD_CHAR
} GstTextOverlayWrapMode;
/**
* GstTextOverlayLineAlign:
* @GST_TEXT_OVERLAY_LINE_ALIGN_LEFT: lines are left-aligned
* @GST_TEXT_OVERLAY_LINE_ALIGN_CENTER: lines are center-aligned
* @GST_TEXT_OVERLAY_LINE_ALIGN_RIGHT: lines are right-aligned
*
* Alignment of text lines relative to each other
*/
typedef enum {
GST_TEXT_OVERLAY_LINE_ALIGN_LEFT = PANGO_ALIGN_LEFT,
GST_TEXT_OVERLAY_LINE_ALIGN_CENTER = PANGO_ALIGN_CENTER,
GST_TEXT_OVERLAY_LINE_ALIGN_RIGHT = PANGO_ALIGN_RIGHT
} GstTextOverlayLineAlign;
/**
* GstTextOverlay:
*
* Opaque textoverlay object structure
*/
struct _GstTextOverlay {
GstElement element;
GstPad *video_sinkpad;
GstPad *text_sinkpad;
GstPad *srcpad;
GstSegment segment;
GstSegment text_segment;
GstBuffer *text_buffer;
gboolean text_linked;
gboolean video_flushing;
gboolean video_eos;
gboolean text_flushing;
gboolean text_eos;
GCond *cond; /* to signal removal of a queued text
* buffer, arrival of a text buffer,
* a text segment update, or a change
* in status (e.g. shutdown, flushing) */
gint width;
gint height;
gint fps_n;
gint fps_d;
GstVideoFormat format;
GstTextOverlayVAlign valign;
GstTextOverlayHAlign halign;
GstTextOverlayWrapMode wrap_mode;
GstTextOverlayLineAlign line_align;
gint xpad;
gint ypad;
gint deltax;
gint deltay;
gdouble xpos;
gdouble ypos;
gchar *default_text;
gboolean want_shading;
gboolean silent;
gboolean wait_text;
guint color;
PangoLayout *layout;
gdouble shadow_offset;
gdouble outline_offset;
guchar *text_image;
gint image_width;
gint image_height;
gint baseline_y;
gboolean auto_adjust_size;
gboolean need_render;
gint shading_value; /* for timeoverlay subclass */
gboolean have_pango_markup;
gboolean use_vertical_render;
};
struct _GstTextOverlayClass {
GstElementClass parent_class;
PangoContext *pango_context;
gchar * (*get_text) (GstTextOverlay *overlay, GstBuffer *video_frame);
};
GType gst_text_overlay_get_type(void) G_GNUC_CONST;
G_END_DECLS
#endif /* __GST_TEXT_OVERLAY_H */