gstreamer/ext/pango/gstbasetextoverlay.h
Lubosz Sarnecki 8a443784c4 basetextoverlay: Add new properties and alignment type for unclamped absolute positions
Introduces [x-absolute, y-absolute] properties
for positioning in +/- MAX_DOUBLE range.

Adds new (h/v)alignment type "absolute" where coordinates
map the text area to be exactly inside of video canvas for [0, 0] - [1, 1]:

[0, 0]: Top-Lefts of video and text are aligned
[0.5, 0.5]: Centers are aligned
[1, 1]: Bottom-Rights are aligned

https://bugzilla.gnome.org/show_bug.cgi?id=761251
2016-03-11 13:20:26 +00:00

225 lines
8.4 KiB
C

/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
* Copyright (C) <2003> David Schleef <ds@schleef.org>
* Copyright (C) <2006> Julien Moutte <julien@moutte.net>
* Copyright (C) <2006> Zeeshan Ali <zeeshan.ali@nokia.com>
* Copyright (C) <2006-2008> Tim-Philipp Müller <tim centricular net>
* Copyright (C) <2009> Young-Ho Cha <ganadist@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndef __GST_BASE_TEXT_OVERLAY_H__
#define __GST_BASE_TEXT_OVERLAY_H__
#include <gst/gst.h>
#include <gst/video/video.h>
#include <gst/video/video-overlay-composition.h>
#include <pango/pangocairo.h>
G_BEGIN_DECLS
#define GST_TYPE_BASE_TEXT_OVERLAY (gst_base_text_overlay_get_type())
#define GST_BASE_TEXT_OVERLAY(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),\
GST_TYPE_BASE_TEXT_OVERLAY, GstBaseTextOverlay))
#define GST_BASE_TEXT_OVERLAY_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),\
GST_TYPE_BASE_TEXT_OVERLAY,GstBaseTextOverlayClass))
#define GST_BASE_TEXT_OVERLAY_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),\
GST_TYPE_BASE_TEXT_OVERLAY, GstBaseTextOverlayClass))
#define GST_IS_BASE_TEXT_OVERLAY(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),\
GST_TYPE_BASE_TEXT_OVERLAY))
#define GST_IS_BASE_TEXT_OVERLAY_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),\
GST_TYPE_BASE_TEXT_OVERLAY))
typedef struct _GstBaseTextOverlay GstBaseTextOverlay;
typedef struct _GstBaseTextOverlayClass GstBaseTextOverlayClass;
/**
* GstBaseTextOverlayVAlign:
* @GST_BASE_TEXT_OVERLAY_VALIGN_BASELINE: draw text on the baseline
* @GST_BASE_TEXT_OVERLAY_VALIGN_BOTTOM: draw text on the bottom
* @GST_BASE_TEXT_OVERLAY_VALIGN_TOP: draw text on top
* @GST_BASE_TEXT_OVERLAY_VALIGN_POS: draw text according to the #GstBaseTextOverlay:ypos property
* @GST_BASE_TEXT_OVERLAY_VALIGN_CENTER: draw text vertically centered
*
* Vertical alignment of the text.
*/
typedef enum {
GST_BASE_TEXT_OVERLAY_VALIGN_BASELINE,
GST_BASE_TEXT_OVERLAY_VALIGN_BOTTOM,
GST_BASE_TEXT_OVERLAY_VALIGN_TOP,
GST_BASE_TEXT_OVERLAY_VALIGN_POS,
GST_BASE_TEXT_OVERLAY_VALIGN_CENTER,
GST_BASE_TEXT_OVERLAY_VALIGN_ABSOLUTE
} GstBaseTextOverlayVAlign;
/**
* GstBaseTextOverlayHAlign:
* @GST_BASE_TEXT_OVERLAY_HALIGN_LEFT: align text left
* @GST_BASE_TEXT_OVERLAY_HALIGN_CENTER: align text center
* @GST_BASE_TEXT_OVERLAY_HALIGN_RIGHT: align text right
* @GST_BASE_TEXT_OVERLAY_HALIGN_POS: position text according to the #GstBaseTextOverlay:xpos property
*
* Horizontal alignment of the text.
*/
/* FIXME 0.11: remove GST_BASE_TEXT_OVERLAY_HALIGN_UNUSED */
typedef enum {
GST_BASE_TEXT_OVERLAY_HALIGN_LEFT,
GST_BASE_TEXT_OVERLAY_HALIGN_CENTER,
GST_BASE_TEXT_OVERLAY_HALIGN_RIGHT,
GST_BASE_TEXT_OVERLAY_HALIGN_UNUSED,
GST_BASE_TEXT_OVERLAY_HALIGN_POS,
GST_BASE_TEXT_OVERLAY_HALIGN_ABSOLUTE
} GstBaseTextOverlayHAlign;
/**
* GstBaseTextOverlayWrapMode:
* @GST_BASE_TEXT_OVERLAY_WRAP_MODE_NONE: no wrapping
* @GST_BASE_TEXT_OVERLAY_WRAP_MODE_WORD: do word wrapping
* @GST_BASE_TEXT_OVERLAY_WRAP_MODE_CHAR: do char wrapping
* @GST_BASE_TEXT_OVERLAY_WRAP_MODE_WORD_CHAR: do word and char wrapping
*
* Whether to wrap the text and if so how.
*/
typedef enum {
GST_BASE_TEXT_OVERLAY_WRAP_MODE_NONE = -1,
GST_BASE_TEXT_OVERLAY_WRAP_MODE_WORD = PANGO_WRAP_WORD,
GST_BASE_TEXT_OVERLAY_WRAP_MODE_CHAR = PANGO_WRAP_CHAR,
GST_BASE_TEXT_OVERLAY_WRAP_MODE_WORD_CHAR = PANGO_WRAP_WORD_CHAR
} GstBaseTextOverlayWrapMode;
/**
* GstBaseTextOverlayLineAlign:
* @GST_BASE_TEXT_OVERLAY_LINE_ALIGN_LEFT: lines are left-aligned
* @GST_BASE_TEXT_OVERLAY_LINE_ALIGN_CENTER: lines are center-aligned
* @GST_BASE_TEXT_OVERLAY_LINE_ALIGN_RIGHT: lines are right-aligned
*
* Alignment of text lines relative to each other
*/
typedef enum {
GST_BASE_TEXT_OVERLAY_LINE_ALIGN_LEFT = PANGO_ALIGN_LEFT,
GST_BASE_TEXT_OVERLAY_LINE_ALIGN_CENTER = PANGO_ALIGN_CENTER,
GST_BASE_TEXT_OVERLAY_LINE_ALIGN_RIGHT = PANGO_ALIGN_RIGHT
} GstBaseTextOverlayLineAlign;
/**
* GstBaseTextOverlay:
*
* Opaque textoverlay object structure
*/
struct _GstBaseTextOverlay {
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;
GMutex lock;
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) */
/* stream metrics */
GstVideoInfo info;
GstVideoFormat format;
gint width;
gint height;
/* properties */
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, outline_color;
PangoLayout *layout;
gboolean auto_adjust_size;
gboolean draw_shadow;
gboolean draw_outline;
gint shading_value; /* for timeoverlay subclass */
gboolean use_vertical_render;
GstBaseTextOverlayVAlign valign;
GstBaseTextOverlayHAlign halign;
GstBaseTextOverlayWrapMode wrap_mode;
GstBaseTextOverlayLineAlign line_align;
/* text pad format */
gboolean have_pango_markup;
/* rendering state */
gboolean need_render;
GstBuffer *text_image;
/* dimension relative to witch the render is done, this is the stream size
* or a portion of the window_size (adapted to aspect ratio) */
gint render_width;
gint render_height;
/* This is (render_width / width) uses to convert to stream scale */
gdouble render_scale;
/* dimension of text_image, the physical dimension */
guint text_width;
guint text_height;
/* position of rendering in image coordinates */
gint text_x;
gint text_y;
/* window dimension, reported in the composition meta params. This is set
* to stream width, height if missing */
gint window_width;
gint window_height;
gdouble shadow_offset;
gdouble outline_offset;
PangoRectangle ink_rect;
PangoRectangle logical_rect;
gboolean attach_compo_to_buffer;
GstVideoOverlayComposition *composition;
GstVideoOverlayComposition *upstream_composition;
};
struct _GstBaseTextOverlayClass {
GstElementClass parent_class;
PangoContext *pango_context;
GMutex *pango_lock;
gchar * (*get_text) (GstBaseTextOverlay *overlay, GstBuffer *video_frame);
};
GType gst_base_text_overlay_get_type(void) G_GNUC_CONST;
G_END_DECLS
#endif /* __GST_BASE_TEXT_OVERLAY_H */