gstreamer/ext/gtk/gtkgstwidget.c
Nicolas Dufresne 0b271a863e gtkglsink: Fix unsafe handling of buffer life time
We need to keep the active buffer (the one we have retreive a
texture id from) otherwise it's racy and upstream may upload
new content before we have rendered or during later redisplay.
2015-08-15 15:55:08 +02:00

190 lines
5.6 KiB
C

/*
* GStreamer
* Copyright (C) 2015 Matthew Waters <matthew@centricular.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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdio.h>
#include "gtkgstwidget.h"
#include <gst/video/video.h>
/**
* SECTION:gtkgstwidget
* @short_description: a #GtkWidget that renders GStreamer video #GstBuffers
* @see_also: #GtkDrawingArea, #GstBuffer
*
* #GtkGstWidget is an #GtkWidget that renders GStreamer video buffers.
*/
G_DEFINE_TYPE (GtkGstWidget, gtk_gst_widget, GTK_TYPE_DRAWING_AREA);
static gboolean
gtk_gst_widget_draw (GtkWidget * widget, cairo_t * cr)
{
GtkGstBaseWidget *gst_widget = (GtkGstBaseWidget *) widget;
guint widget_width, widget_height;
cairo_surface_t *surface;
GstVideoFrame frame;
widget_width = gtk_widget_get_allocated_width (widget);
widget_height = gtk_widget_get_allocated_height (widget);
GTK_GST_BASE_WIDGET_LOCK (gst_widget);
/* There is not much to optimize in term of redisplay, so simply swap the
* pending_buffer with the active buffer */
if (gst_widget->pending_buffer) {
if (gst_widget->buffer)
gst_buffer_unref (gst_widget->buffer);
gst_widget->buffer = gst_widget->pending_buffer;
gst_widget->pending_buffer = NULL;
}
/* failed to map the video frame */
if (gst_widget->negotiated && gst_widget->buffer
&& gst_video_frame_map (&frame, &gst_widget->v_info,
gst_widget->buffer, GST_MAP_READ)) {
gdouble scale_x = (gdouble) widget_width / gst_widget->display_width;
gdouble scale_y = (gdouble) widget_height / gst_widget->display_height;
GstVideoRectangle result;
cairo_format_t format;
gst_widget->v_info = frame.info;
if (frame.info.finfo->format == GST_VIDEO_FORMAT_ARGB ||
frame.info.finfo->format == GST_VIDEO_FORMAT_BGRA) {
format = CAIRO_FORMAT_ARGB32;
} else {
format = CAIRO_FORMAT_RGB24;
}
surface = cairo_image_surface_create_for_data (frame.data[0],
format, frame.info.width, frame.info.height, frame.info.stride[0]);
if (gst_widget->force_aspect_ratio) {
GstVideoRectangle src, dst;
src.x = 0;
src.y = 0;
src.w = gst_widget->display_width;
src.h = gst_widget->display_height;
dst.x = 0;
dst.y = 0;
dst.w = widget_width;
dst.h = widget_height;
gst_video_sink_center_rect (src, dst, &result, TRUE);
scale_x = scale_y = MIN (scale_x, scale_y);
} else {
result.x = 0;
result.y = 0;
result.w = widget_width;
result.h = widget_height;
}
if (gst_widget->ignore_alpha) {
GdkRGBA color = { 0.0, 0.0, 0.0, 1.0 };
gdk_cairo_set_source_rgba (cr, &color);
if (result.x > 0) {
cairo_rectangle (cr, 0, 0, result.x, widget_height);
cairo_fill (cr);
}
if (result.y > 0) {
cairo_rectangle (cr, 0, 0, widget_width, result.y);
cairo_fill (cr);
}
if (result.w < widget_width) {
cairo_rectangle (cr, result.x + result.w, 0, widget_width - result.w,
widget_height);
cairo_fill (cr);
}
if (result.h < widget_height) {
cairo_rectangle (cr, 0, result.y + result.h, widget_width,
widget_height - result.h);
cairo_fill (cr);
}
}
scale_x *= (gdouble) gst_widget->display_width / (gdouble) frame.info.width;
scale_y *=
(gdouble) gst_widget->display_height / (gdouble) frame.info.height;
cairo_translate (cr, result.x, result.y);
cairo_scale (cr, scale_x, scale_y);
cairo_rectangle (cr, 0, 0, result.w, result.h);
cairo_set_source_surface (cr, surface, 0, 0);
cairo_paint (cr);
cairo_surface_destroy (surface);
gst_video_frame_unmap (&frame);
} else {
GdkRGBA color;
if (gst_widget->ignore_alpha) {
color.red = color.blue = color.green = 0.0;
color.alpha = 1.0;
} else {
gtk_style_context_get_color (gtk_widget_get_style_context (widget),
GTK_STATE_FLAG_NORMAL, &color);
}
gdk_cairo_set_source_rgba (cr, &color);
cairo_rectangle (cr, 0, 0, widget_width, widget_height);
cairo_fill (cr);
}
GTK_GST_BASE_WIDGET_UNLOCK (gst_widget);
return FALSE;
}
static void
gtk_gst_widget_finalize (GObject * object)
{
gtk_gst_base_widget_finalize (object);
G_OBJECT_CLASS (gtk_gst_widget_parent_class)->finalize (object);
}
static void
gtk_gst_widget_class_init (GtkGstWidgetClass * klass)
{
GObjectClass *gobject_klass = (GObjectClass *) klass;
GtkWidgetClass *widget_klass = (GtkWidgetClass *) klass;
gtk_gst_base_widget_class_init (GTK_GST_BASE_WIDGET_CLASS (klass));
gobject_klass->finalize = gtk_gst_widget_finalize;
widget_klass->draw = gtk_gst_widget_draw;
}
static void
gtk_gst_widget_init (GtkGstWidget * widget)
{
gtk_gst_base_widget_init (GTK_GST_BASE_WIDGET (widget));
}
GtkWidget *
gtk_gst_widget_new (void)
{
return (GtkWidget *) g_object_new (GTK_TYPE_GST_WIDGET, NULL);
}