gstreamer/ext/closedcaption/gstceaccoverlay.h
Edward Hervey a41fb3c6df ceaccoverlay: New CEA-708 Closed Caption decoder and overlayer
This new element allows decoding and overlaying CEA-708 Closed Caption
streams over video.

* Supports CDP and cc_data closedcaption/x-cea-708 streams
* Uses pango to render CC stream
* Support GstVideoOverlayComposition meta if downstream supports is

Tested on various test files.

Remains to be fixed/improved:
* Switch to GstByteReader (for code safety)
* Switch to GString (instead of manual pango string construction)
* Move pango/rendering code outside of main 708 decoder file (so
  that actual CC parser/decoder can be (re)used in other scenarios).

Initial patches and improvements by:
* CableLabs RUIH-RI Team <ruihri@cablelabs.com>
* Steve Maynard <steve@secondstryke.com>
* cjun.wang" <cjun.wang@samsung.com>

https://bugzilla.gnome.org/show_bug.cgi?id=704881
2018-05-28 15:29:01 +02:00

136 lines
4 KiB
C

/* GStreamer
* Copyright (C) 2015 Samsung Electronics Co., Ltd.
* @Author: Chengjun Wang <cjun.wang@samsung.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_CEA_CC_OVERLAY_H__
#define __GST_CEA_CC_OVERLAY_H__
#include <gst/gst.h>
#include <pango/pangocairo.h>
#include <gstcea708decoder.h>
G_BEGIN_DECLS
#define GST_TYPE_CEA_CC_OVERLAY \
(gst_cea_cc_overlay_get_type())
#define GST_CEA_CC_OVERLAY(obj) \
(G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_CEA_CC_OVERLAY,GstCeaCcOverlay))
#define GST_CEA_CC_OVERLAY_CLASS(klass) \
(G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_CEA_CC_OVERLAY,GstCeaCcOverlayClass))
#define GST_CEA_CC_OVERLAY_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),\
GST_TYPE_CEA_CC_OVERLAY, GstCeaCcOverlayClass))
#define GST_IS_CEA_CC_OVERLAY(obj) \
(G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_CEA_CC_OVERLAY))
#define GST_IS_CEA_CC_OVERLAY_CLASS(klass) \
(G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_CEA_CC_OVERLAY))
typedef struct _GstCeaCcOverlay GstCeaCcOverlay;
typedef struct _GstCeaCcOverlayClass GstCeaCcOverlayClass;
typedef enum
{
CCTYPE_608_CC1 = 0,
CCTYPE_608_CC2,
CCTYPE_708_ADD,
CCTYPE_708_START,
} DtvccType;
/**
* GstBaseTextOverlayHAlign:
* @GST_CEA_CC_OVERLAY_WIN_H_LEFT: closed caption window horizontal anchor left
* @GST_CEA_CC_OVERLAY_WIN_H_CENTER: closed caption window horizontal anchor center
* @GST_CEA_CC_OVERLAY_WIN_H_RIGHT: closed caption window horizontal anchor right
* @GST_CEA_CC_OVERLAY_WIN_H_AUTO: closed caption window horizontal anchor auto
*
* Closed Caption Window Horizontal anchor position.
*/
typedef enum
{
GST_CEA_CC_OVERLAY_WIN_H_LEFT,
GST_CEA_CC_OVERLAY_WIN_H_CENTER,
GST_CEA_CC_OVERLAY_WIN_H_RIGHT,
GST_CEA_CC_OVERLAY_WIN_H_AUTO
} GstCeaCcOverlayWinHPos;
/**
* GstCeaCcOverlay:
*
* Opaque ccoverlay data structure.
*/
struct _GstCeaCcOverlay
{
GstElement parent;
GstPad *video_sinkpad;
GstPad *cc_sinkpad;
GstPad *srcpad;
/* There are two possible 608 streams encapsulated by 708 */
gint16 cea608_index[NUM_608_CCTYPES];
gint16 cea708_index;
guint8 cea608_buffer[NUM_608_CCTYPES][DTVCC_LENGTH];
guint8 cea708_buffer[DTVCC_LENGTH];
/* TRUE if input is CDP, FALSE if cc_data triplet */
gboolean is_cdp;
GstSegment segment;
GstSegment cc_segment;
GstVideoOverlayComposition *current_composition;
guint64 current_comp_start_time;
GstVideoOverlayComposition *next_composition;
guint64 next_comp_start_time;
GstCeaCcOverlayWinHPos default_window_h_pos;
gboolean cc_pad_linked;
gboolean video_flushing;
gboolean video_eos;
gboolean cc_flushing;
gboolean cc_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) */
GstVideoInfo info;
GstVideoFormat format;
gint width;
gint height;
gboolean silent;
Cea708Dec *decoder;
gint image_width;
gint image_height;
gboolean need_update;
gboolean attach_compo_to_buffer;
};
/* FIXME : Pango context and MT-safe since 1.32.6 */
struct _GstCeaCcOverlayClass
{
GstElementClass parent_class;
PangoContext *pango_context;
GMutex *pango_lock;
};
GType gst_cea_cc_overlay_get_type (void);
G_END_DECLS
#endif /* __GST_CEA_CC_OVERLAY_H__ */