gstreamer/ext/opencv/gsttextoverlay.c
Sreerenj Balachandran d6a1eebf37 opencv text overlay: rename and docuemnt
Rename the element textwrite to opencvtextoverlay. Add proper structuring to
opencv textoverlay element.

Fixes: #640561
2011-03-28 20:31:35 +03:00

413 lines
13 KiB
C

/*
* GStreamer
* Copyright (C) 2005 Thomas Vander Stichele <thomas@apestaart.org>
* Copyright (C) 2005 Ronald S. Bultje <rbultje@ronald.bitfreak.net>
* Copyright (C) 2010 Sreerenj Balachandran <bsreerenj@gmail.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* Alternatively, the contents of this file may be used under the
* GNU Lesser General Public License Version 2.1 (the "LGPL"), in
* which case the following provisions apply instead of the ones
* mentioned above:
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-opencvtextoverlay
*
* opencvtextoverlay renders the text on top of the video frames
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch-0.10 videotestsrc ! ffmpegcolorspace ! opencvtextoverlay text="Opencv Text Overlay " ! ffmpegcolorspace ! xvimagesink
* ]|
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <gst/gst.h>
#include "gstopencvutils.h"
#include "gsttextoverlay.h"
GST_DEBUG_CATEGORY_STATIC (gst_opencv_text_overlay_debug);
#define GST_CAT_DEFAULT gst_opencv_opencv_text_overlay_debug
#define DEFAULT_PROP_TEXT ""
#define DEFAULT_PROP_WIDTH 1
#define DEFAULT_PROP_HEIGHT 1
#define DEFAULT_PROP_XPOS 50
#define DEFAULT_PROP_YPOS 50
#define DEFAULT_PROP_THICKNESS 2
#define DEFAULT_PROP_COLOR 0
/* Filter signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
#define DEFAULT_WIDTH 1.0
#define DEFAULT_HEIGHT 1.0
enum
{
PROP_0,
PROP_XPOS,
PROP_YPOS,
PROP_THICKNESS,
PROP_COLOR_R,
PROP_COLOR_G,
PROP_COLOR_B,
PROP_TEXT,
PROP_HEIGHT,
PROP_WIDTH
};
/* the capabilities of the inputs and outputs.
*
* describe the real formats here.
*/
static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (GST_VIDEO_CAPS_RGB)
);
static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (GST_VIDEO_CAPS_RGB)
);
GST_BOILERPLATE (GstOpencvTextOverlay, gst_opencv_text_overlay, GstElement,
GST_TYPE_ELEMENT);
static void gst_opencv_text_overlay_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec);
static void gst_opencv_text_overlay_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec);
static gboolean gst_opencv_text_overlay_set_caps (GstPad * pad, GstCaps * caps);
static GstFlowReturn gst_opencv_text_overlay_chain (GstPad * pad,
GstBuffer * buf);
/* Clean up */
static void
gst_opencv_text_overlay_finalize (GObject * obj)
{
GstOpencvTextOverlay *filter = GST_OPENCV_TEXT_OVERLAY (obj);
if (filter->cvImage) {
cvReleaseImage (&filter->cvImage);
}
G_OBJECT_CLASS (parent_class)->finalize (obj);
}
/* GObject vmethod implementations */
static void
gst_opencv_text_overlay_base_init (gpointer gclass)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (gclass);
gst_element_class_set_details_simple (element_class,
"opencvtextoverlay",
"Filter/Effect/Video",
"Write text on the top of video", "sreerenj<bsreerenj@gmail.com>");
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&src_factory));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sink_factory));
}
/* initialize the opencvtextoverlay's class */
static void
gst_opencv_text_overlay_class_init (GstOpencvTextOverlayClass * klass)
{
GObjectClass *gobject_class;
gobject_class = (GObjectClass *) klass;
parent_class = g_type_class_peek_parent (klass);
gobject_class->finalize =
GST_DEBUG_FUNCPTR (gst_opencv_text_overlay_finalize);
gobject_class->set_property = gst_opencv_text_overlay_set_property;
gobject_class->get_property = gst_opencv_text_overlay_get_property;
g_object_class_install_property (gobject_class, PROP_TEXT,
g_param_spec_string ("text", "text",
"Text to be display.", DEFAULT_PROP_TEXT,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_XPOS,
g_param_spec_int ("xpos", "horizontal position",
"Sets the Horizontal position", 0, G_MAXINT,
DEFAULT_PROP_XPOS, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_YPOS,
g_param_spec_int ("ypos", "vertical position",
"Sets the Vertical position", 0, G_MAXINT,
DEFAULT_PROP_YPOS, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_THICKNESS,
g_param_spec_int ("thickness", "font thickness",
"Sets the Thickness of Font", 0, G_MAXINT,
DEFAULT_PROP_THICKNESS, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_COLOR_R,
g_param_spec_int ("colorR", "color -Red ",
"Sets the color -R", 0, 255,
DEFAULT_PROP_COLOR, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_COLOR_G,
g_param_spec_int ("colorG", "color -Green",
"Sets the color -G", 0, 255,
DEFAULT_PROP_COLOR, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_COLOR_B,
g_param_spec_int ("colorB", "color -Blue",
"Sets the color -B", 0, 255,
DEFAULT_PROP_COLOR, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_HEIGHT,
g_param_spec_double ("height", "Height",
"Sets the height of fonts", 1.0, 5.0,
DEFAULT_HEIGHT, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_WIDTH,
g_param_spec_double ("width", "Width",
"Sets the width of fonts", 1.0, 5.0,
DEFAULT_WIDTH, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
}
/* initialize the new element
* instantiate pads and add them to element
* set pad calback functions
* initialize instance structure
*/
static void
gst_opencv_text_overlay_init (GstOpencvTextOverlay * filter,
GstOpencvTextOverlayClass * gclass)
{
filter->sinkpad = gst_pad_new_from_static_template (&sink_factory, "sink");
gst_pad_set_setcaps_function (filter->sinkpad,
GST_DEBUG_FUNCPTR (gst_opencv_text_overlay_set_caps));
gst_pad_set_getcaps_function (filter->sinkpad,
GST_DEBUG_FUNCPTR (gst_pad_proxy_getcaps));
gst_pad_set_chain_function (filter->sinkpad,
GST_DEBUG_FUNCPTR (gst_opencv_text_overlay_chain));
filter->srcpad = gst_pad_new_from_static_template (&src_factory, "src");
gst_pad_set_getcaps_function (filter->srcpad,
GST_DEBUG_FUNCPTR (gst_pad_proxy_getcaps));
gst_element_add_pad (GST_ELEMENT (filter), filter->sinkpad);
gst_element_add_pad (GST_ELEMENT (filter), filter->srcpad);
filter->textbuf = g_strdup (DEFAULT_PROP_TEXT);
filter->width = DEFAULT_PROP_WIDTH;
filter->height = DEFAULT_PROP_HEIGHT;
filter->xpos = DEFAULT_PROP_XPOS;
filter->ypos = DEFAULT_PROP_YPOS;
filter->thickness = DEFAULT_PROP_THICKNESS;
filter->colorR = DEFAULT_PROP_COLOR;
filter->colorG = DEFAULT_PROP_COLOR;
filter->colorB = DEFAULT_PROP_COLOR;
}
static void
gst_opencv_text_overlay_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstOpencvTextOverlay *filter = GST_OPENCV_TEXT_OVERLAY (object);
switch (prop_id) {
case PROP_TEXT:
g_free (filter->textbuf);
filter->textbuf = g_value_dup_string (value);
break;
case PROP_XPOS:
filter->xpos = g_value_get_int (value);
break;
case PROP_YPOS:
filter->ypos = g_value_get_int (value);
break;
case PROP_THICKNESS:
filter->thickness = g_value_get_int (value);
break;
case PROP_COLOR_R:
filter->colorR = g_value_get_int (value);
break;
case PROP_COLOR_G:
filter->colorG = g_value_get_int (value);
break;
case PROP_COLOR_B:
filter->colorB = g_value_get_int (value);
break;
case PROP_HEIGHT:
filter->height = g_value_get_double (value);
break;
case PROP_WIDTH:
filter->width = g_value_get_double (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_opencv_text_overlay_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstOpencvTextOverlay *filter = GST_OPENCV_TEXT_OVERLAY (object);
switch (prop_id) {
case PROP_TEXT:
g_value_set_string (value, filter->textbuf);
break;
case PROP_XPOS:
g_value_set_int (value, filter->xpos);
break;
case PROP_YPOS:
g_value_set_int (value, filter->ypos);
break;
case PROP_THICKNESS:
g_value_set_int (value, filter->thickness);
break;
case PROP_COLOR_R:
g_value_set_int (value, filter->colorR);
break;
case PROP_COLOR_G:
g_value_set_int (value, filter->colorG);
break;
case PROP_COLOR_B:
g_value_set_int (value, filter->colorB);
break;
case PROP_HEIGHT:
g_value_set_double (value, filter->height);
break;
case PROP_WIDTH:
g_value_set_double (value, filter->width);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/* GstElement vmethod implementations */
/* this function handles the link with other elements */
static gboolean
gst_opencv_text_overlay_set_caps (GstPad * pad, GstCaps * caps)
{
GstOpencvTextOverlay *filter;
GstPad *otherpad;
gint width, height;
GstStructure *structure;
filter = GST_OPENCV_TEXT_OVERLAY (gst_pad_get_parent (pad));
structure = gst_caps_get_structure (caps, 0);
gst_structure_get_int (structure, "width", &width);
gst_structure_get_int (structure, "height", &height);
filter->cvImage = cvCreateImage (cvSize (width, height), IPL_DEPTH_8U, 3);
filter->cvStorage = cvCreateMemStorage (0);
otherpad = (pad == filter->srcpad) ? filter->sinkpad : filter->srcpad;
gst_object_unref (filter);
return gst_pad_set_caps (otherpad, caps);
}
/* chain function
* this function does the actual processing
*/
static GstFlowReturn
gst_opencv_text_overlay_chain (GstPad * pad, GstBuffer * buf)
{
GstOpencvTextOverlay *filter;
filter = GST_OPENCV_TEXT_OVERLAY (GST_OBJECT_PARENT (pad));
filter->cvImage->imageData = (char *) GST_BUFFER_DATA (buf);
cvInitFont (&(filter->font), CV_FONT_VECTOR0, filter->width, filter->height,
0, filter->thickness, 0);
buf = gst_buffer_make_writable (buf);
cvPutText (filter->cvImage, filter->textbuf, cvPoint (filter->xpos,
filter->ypos), &(filter->font), cvScalar (filter->colorR,
filter->colorG, filter->colorB, 0));
return gst_pad_push (filter->srcpad, buf);
}
/* entry point to initialize the plug-in
* initialize the plug-in itself
* register the element factories and other features
*/
gboolean
gst_opencv_text_overlay_plugin_init (GstPlugin * plugin)
{
/* debug category for fltering log messages
*
* exchange the string 'Template opencvtextoverlay' with your description
*/
GST_DEBUG_CATEGORY_INIT (gst_opencv_text_overlay_debug, "opencvtextoverlay",
0, "Template opencvtextoverlay");
return gst_element_register (plugin, "opencvtextoverlay", GST_RANK_NONE,
GST_TYPE_OPENCV_TEXT_OVERLAY);
}