winscreencap: Add dxgiscreencapsrc element.

This element uses the Desktop Duplication API to capture the desktop screen at high speed.
It supports Windows 8 or later.

It has the following features compared to other elements:
 * Runs faster.
 * It works in High DPI environment.
 * Draws an accurate mouse cursor.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/863>

sys/winscreencap/dxgicapture.h

@@ -0,0 +1,83 @@
+/* GStreamer
+ * Copyright (C) 2019 OKADA Jun-ichi <okada@abt.jp>
+ *
+ * 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 __DXGICAP_H__
+#define __DXGICAP_H__
+
+#define COBJMACROS
+#include <d3d11.h>
+#include <dxgi.h>
+#include <dxgi1_2.h>
+#undef COBJMACROS
+
+#include <gst/gst.h>
+#include <gst/base/gstpushsrc.h>
+#include <gst/video/video.h>
+
+#define RECT_WIDTH(r) (r.right - r.left)
+#define RECT_HEIGHT(r) (r.bottom - r.top)
+
+#define HR_FAILED_AND(hr,func,and) \
+  G_STMT_START { \
+    if (FAILED (hr)) { \
+      gchar *msg = get_hresult_to_string (hr); \
+      GST_ERROR_OBJECT (src, #func " failed (%x): %s", (guint) hr, msg); \
+      g_free (msg); \
+      and; \
+    } \
+  } G_STMT_END
+
+#define HR_FAILED_RET(hr,func,ret) HR_FAILED_AND(hr,func,return ret)
+
+#define HR_FAILED_GOTO(hr,func,where) HR_FAILED_AND(hr,func,goto where)
+
+#define HR_FAILED_INFO(hr, func) \
+  G_STMT_START { \
+    if (FAILED (hr)) { \
+      gchar *msg = get_hresult_to_string (hr); \
+      GST_INFO_OBJECT (src, #func " failed (%x): %s", (guint) hr, msg); \
+      g_free (msg); \
+    } \
+  } G_STMT_END
+
+
+typedef struct _GstDXGIScreenCapSrc GstDXGIScreenCapSrc;
+
+typedef struct _DxgiCapture DxgiCapture;
+
+DxgiCapture *dxgicap_new (HMONITOR monitor, GstDXGIScreenCapSrc * src);
+void dxgicap_destory (DxgiCapture * _this);
+
+gboolean dxgicap_start (DxgiCapture * _this);
+void dxgicap_stop (DxgiCapture * _this);
+
+gint dxgicap_acquire_next_frame (DxgiCapture * _this, gboolean show_cursor,
+    guint timeout);
+gboolean dxgicap_copy_buffer (DxgiCapture * _this, gboolean show_cursor,
+    LPRECT src_rect, GstVideoInfo * video_info, GstBuffer * buf);
+
+HMONITOR get_hmonitor_by_device_name (const gchar * device_name);
+HMONITOR get_hmonitor_primary (void);
+HMONITOR get_hmonitor_by_index (int index);
+
+gboolean get_monitor_physical_size (HMONITOR hmonitor, LPRECT rect);
+
+gchar *get_hresult_to_string (HRESULT hr);
+
+#endif /* __DXGICAP_H__ */

sys/winscreencap/gstdxgiscreencapsrc.c

@@ -0,0 +1,564 @@
+/* GStreamer
+ * Copyright (C) 2019 OKADA Jun-ichi <okada@abt.jp>
+ *
+ * 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.
+ */
+
+/**
+ * SECTION:element-dxgiscreencapsrc
+ * @title: dxgiscreencapsrc
+ *
+ * This element uses DXGI Desktop Duplication API.
+ * The default is capturing the whole desktop, but #GstDXGIScreenCapSrc:x,
+ * #GstDXGIScreenCapSrc:y, #GstDXGIScreenCapSrc:width and
+ * #GstDXGIScreenCapSrc:height can be used to select a particular region.
+ * Use #GstDXGIScreenCapSrc:monitor for changing which monitor to capture
+ * from.
+ *
+ * ## Example pipelines
+ * |[
+ * gst-launch-1.0 dxgiscreencapsrc ! videoconvert ! dshowvideosink
+ * ]| Capture the desktop and display it.
+ * |[
+ * gst-launch-1.0 dxgiscreencapsrc x=100 y=100 width=320 height=240 !
+ * videoconvert ! dshowvideosink
+ * ]| Capture a portion of the desktop and display it.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/video/video.h>
+#include "gstdxgiscreencapsrc.h"
+#include "dxgicapture.h"
+
+GST_DEBUG_CATEGORY_STATIC (dxgiscreencapsrc_debug);
+
+struct _GstDXGIScreenCapSrc
+{
+  /* Parent */
+  GstPushSrc src;
+
+  /* Properties */
+  gint capture_x;
+  gint capture_y;
+  gint capture_w;
+  gint capture_h;
+  guint monitor;
+  gchar *device_name;
+  gboolean show_cursor;
+
+  /* Source pad frame rate */
+  gint rate_numerator;
+  gint rate_denominator;
+
+  /* Runtime variables */
+  RECT screen_rect;
+  RECT src_rect;
+  guint64 frame_number;
+  GstClockID clock_id;
+  GstVideoInfo video_info;
+
+  /*DXGI capture */
+  DxgiCapture *dxgi_capture;
+};
+
+static GstStaticPadTemplate src_template = GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS (GST_VIDEO_CAPS_MAKE ("BGRA")));
+
+#define gst_dxgi_screen_cap_src_parent_class parent_class
+G_DEFINE_TYPE (GstDXGIScreenCapSrc, gst_dxgi_screen_cap_src, GST_TYPE_PUSH_SRC);
+
+#define DEFAULT_MONITOR (-1)
+#define DEFAULT_DEVICE_NAME (NULL)
+#define DEFAULT_SHOW_CURSOR (FALSE)
+#define DEFAULT_X_POS (0)
+#define DEFAULT_Y_POS (0)
+#define DEFAULT_WIDTH (0)
+#define DEFAULT_HEIGHT (0)
+
+enum
+{
+  PROP_0,
+  PROP_MONITOR,
+  PROP_DEVICE_NAME,
+  PROP_SHOW_CURSOR,
+  PROP_X_POS,
+  PROP_Y_POS,
+  PROP_WIDTH,
+  PROP_HEIGHT
+};
+
+static void gst_dxgi_screen_cap_src_dispose (GObject * object);
+static void gst_dxgi_screen_cap_src_set_property (GObject * object,
+    guint prop_id, const GValue * value, GParamSpec * pspec);
+static void gst_dxgi_screen_cap_src_get_property (GObject * object,
+    guint prop_id, GValue * value, GParamSpec * pspec);
+
+static GstCaps *gst_dxgi_screen_cap_src_fixate (GstBaseSrc * bsrc,
+    GstCaps * caps);
+static gboolean gst_dxgi_screen_cap_src_set_caps (GstBaseSrc * bsrc,
+    GstCaps * caps);
+static GstCaps *gst_dxgi_screen_cap_src_get_caps (GstBaseSrc * bsrc,
+    GstCaps * filter);
+static gboolean gst_dxgi_screen_cap_src_start (GstBaseSrc * bsrc);
+static gboolean gst_dxgi_screen_cap_src_stop (GstBaseSrc * bsrc);
+
+static gboolean gst_dxgi_screen_cap_src_unlock (GstBaseSrc * bsrc);
+
+static GstFlowReturn gst_dxgi_screen_cap_src_fill (GstPushSrc * pushsrc,
+    GstBuffer * buffer);
+
+
+static HMONITOR _get_hmonitor (GstDXGIScreenCapSrc * src);
+
+/* Implementation. */
+static void
+gst_dxgi_screen_cap_src_class_init (GstDXGIScreenCapSrcClass * klass)
+{
+  GObjectClass *go_class;
+  GstElementClass *e_class;
+  GstBaseSrcClass *bs_class;
+  GstPushSrcClass *ps_class;
+
+  go_class = G_OBJECT_CLASS (klass);
+  e_class = GST_ELEMENT_CLASS (klass);
+  bs_class = GST_BASE_SRC_CLASS (klass);
+  ps_class = GST_PUSH_SRC_CLASS (klass);
+
+  go_class->set_property = gst_dxgi_screen_cap_src_set_property;
+  go_class->get_property = gst_dxgi_screen_cap_src_get_property;
+
+  go_class->dispose = GST_DEBUG_FUNCPTR (gst_dxgi_screen_cap_src_dispose);
+  bs_class->get_caps = GST_DEBUG_FUNCPTR (gst_dxgi_screen_cap_src_get_caps);
+  bs_class->set_caps = GST_DEBUG_FUNCPTR (gst_dxgi_screen_cap_src_set_caps);
+  bs_class->start = GST_DEBUG_FUNCPTR (gst_dxgi_screen_cap_src_start);
+  bs_class->stop = GST_DEBUG_FUNCPTR (gst_dxgi_screen_cap_src_stop);
+  bs_class->unlock = GST_DEBUG_FUNCPTR (gst_dxgi_screen_cap_src_unlock);
+  bs_class->fixate = GST_DEBUG_FUNCPTR (gst_dxgi_screen_cap_src_fixate);
+  ps_class->fill = GST_DEBUG_FUNCPTR (gst_dxgi_screen_cap_src_fill);
+
+  g_object_class_install_property (go_class, PROP_MONITOR,
+      g_param_spec_int ("monitor", "Monitor",
+          "Which monitor to use (-1 = primary monitor and default)",
+          DEFAULT_MONITOR, G_MAXINT, DEFAULT_MONITOR, G_PARAM_READWRITE));
+  g_object_class_install_property (go_class, PROP_DEVICE_NAME,
+      g_param_spec_string ("device-name", "Monitor device name",
+          "Which monitor to use by device name (e.g. \"\\\\\\\\.\\\\DISPLAY1\")",
+          DEFAULT_DEVICE_NAME, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+  g_object_class_install_property (go_class, PROP_SHOW_CURSOR,
+      g_param_spec_boolean ("cursor",
+          "Show mouse cursor",
+          "Whether to show mouse cursor (default off)",
+          DEFAULT_SHOW_CURSOR, G_PARAM_READWRITE));
+  g_object_class_install_property (go_class, PROP_X_POS,
+      g_param_spec_int ("x", "X",
+          "Horizontal coordinate of top left corner for the screen capture "
+          "area", 0, G_MAXINT, DEFAULT_X_POS, G_PARAM_READWRITE));
+  g_object_class_install_property (go_class, PROP_Y_POS,
+      g_param_spec_int ("y", "Y",
+          "Vertical coordinate of top left corner for the screen capture "
+          "area", 0, G_MAXINT, DEFAULT_Y_POS, G_PARAM_READWRITE));
+  g_object_class_install_property (go_class, PROP_WIDTH,
+      g_param_spec_int ("width", "Width",
+          "Width of screen capture area (0 = maximum)",
+          0, G_MAXINT, DEFAULT_WIDTH, G_PARAM_READWRITE));
+  g_object_class_install_property (go_class, PROP_HEIGHT,
+      g_param_spec_int ("height", "Height",
+          "Height of screen capture area (0 = maximum)",
+          0, G_MAXINT, DEFAULT_HEIGHT, G_PARAM_READWRITE));
+
+  gst_element_class_add_static_pad_template (e_class, &src_template);
+
+  gst_element_class_set_static_metadata (e_class,
+      "DirectX DXGI screen capture source",
+      "Source/Video", "Captures screen", "OKADA Jun-ichi <okada@abt.jp>");
+
+  GST_DEBUG_CATEGORY_INIT (dxgiscreencapsrc_debug, "dxgiscreencapsrc", 0,
+      "DirectX DXGI screen capture source");
+}
+
+static void
+gst_dxgi_screen_cap_src_init (GstDXGIScreenCapSrc * src)
+{
+  /* Set src element inital values... */
+  src->capture_x = DEFAULT_X_POS;
+  src->capture_y = DEFAULT_Y_POS;
+  src->capture_w = DEFAULT_WIDTH;
+  src->capture_h = DEFAULT_HEIGHT;
+
+  src->monitor = DEFAULT_MONITOR;
+  src->device_name = DEFAULT_DEVICE_NAME;
+  src->show_cursor = DEFAULT_SHOW_CURSOR;
+
+  src->dxgi_capture = NULL;
+
+  gst_base_src_set_live (GST_BASE_SRC (src), TRUE);
+  gst_base_src_set_format (GST_BASE_SRC (src), GST_FORMAT_TIME);
+}
+
+static void
+gst_dxgi_screen_cap_src_dispose (GObject * object)
+{
+  GstDXGIScreenCapSrc *src = GST_DXGI_SCREEN_CAP_SRC (object);
+
+  g_free (src->device_name);
+  src->device_name = NULL;
+
+  dxgicap_destory (src->dxgi_capture);
+  src->dxgi_capture = NULL;
+
+  G_OBJECT_CLASS (parent_class)->dispose (object);
+}
+
+static void
+gst_dxgi_screen_cap_src_set_property (GObject * object,
+    guint prop_id, const GValue * value, GParamSpec * pspec)
+{
+  GstDXGIScreenCapSrc *src = GST_DXGI_SCREEN_CAP_SRC (object);
+
+  switch (prop_id) {
+    case PROP_MONITOR:
+      src->monitor = g_value_get_int (value);
+      break;
+    case PROP_DEVICE_NAME:
+      g_free (src->device_name);
+      src->device_name = g_value_dup_string (value);
+      break;
+    case PROP_SHOW_CURSOR:
+      src->show_cursor = g_value_get_boolean (value);
+      break;
+    case PROP_X_POS:
+      src->capture_x = g_value_get_int (value);
+      break;
+    case PROP_Y_POS:
+      src->capture_y = g_value_get_int (value);
+      break;
+    case PROP_WIDTH:
+      src->capture_w = g_value_get_int (value);
+      break;
+    case PROP_HEIGHT:
+      src->capture_h = g_value_get_int (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  };
+}
+
+static void
+gst_dxgi_screen_cap_src_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec)
+{
+  GstDXGIScreenCapSrc *src = GST_DXGI_SCREEN_CAP_SRC (object);
+
+  switch (prop_id) {
+    case PROP_MONITOR:
+      g_value_set_int (value, src->monitor);
+      break;
+    case PROP_DEVICE_NAME:
+      g_value_set_string (value, src->device_name);
+      break;
+    case PROP_SHOW_CURSOR:
+      g_value_set_boolean (value, src->show_cursor);
+      break;
+    case PROP_X_POS:
+      g_value_set_int (value, src->capture_x);
+      break;
+    case PROP_Y_POS:
+      g_value_set_int (value, src->capture_y);
+      break;
+    case PROP_WIDTH:
+      g_value_set_int (value, src->capture_w);
+      break;
+    case PROP_HEIGHT:
+      g_value_set_int (value, src->capture_h);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  };
+}
+
+static GstCaps *
+gst_dxgi_screen_cap_src_fixate (GstBaseSrc * bsrc, GstCaps * caps)
+{
+  GstStructure *structure;
+
+  caps = gst_caps_make_writable (caps);
+
+  structure = gst_caps_get_structure (caps, 0);
+
+  gst_structure_fixate_field_nearest_int (structure, "width", 640);
+  gst_structure_fixate_field_nearest_int (structure, "height", 480);
+  gst_structure_fixate_field_nearest_fraction (structure, "framerate", 30, 1);
+
+  caps = GST_BASE_SRC_CLASS (parent_class)->fixate (bsrc, caps);
+
+  return caps;
+}
+
+static gboolean
+gst_dxgi_screen_cap_src_set_caps (GstBaseSrc * bsrc, GstCaps * caps)
+{
+  GstDXGIScreenCapSrc *src = GST_DXGI_SCREEN_CAP_SRC (bsrc);
+  GstStructure *structure;
+
+  structure = gst_caps_get_structure (caps, 0);
+
+  src->src_rect = src->screen_rect;
+  if (src->capture_w && src->capture_h) {
+    src->src_rect.left += src->capture_x;
+    src->src_rect.top += src->capture_y;
+    src->src_rect.right = src->src_rect.left + src->capture_w;
+    src->src_rect.bottom = src->src_rect.top + src->capture_h;
+  }
+
+  gst_structure_get_fraction (structure, "framerate",
+      &src->rate_numerator, &src->rate_denominator);
+
+  GST_DEBUG_OBJECT (src, "set_caps size %dx%d, %d/%d fps",
+      (gint) RECT_WIDTH (src->src_rect),
+      (gint) RECT_HEIGHT (src->src_rect),
+      src->rate_numerator, src->rate_denominator);
+
+  gst_video_info_from_caps (&src->video_info, caps);
+  gst_base_src_set_blocksize (bsrc, GST_VIDEO_INFO_SIZE (&src->video_info));
+  return TRUE;
+}
+
+static GstCaps *
+gst_dxgi_screen_cap_src_get_caps (GstBaseSrc * bsrc, GstCaps * filter)
+{
+  GstDXGIScreenCapSrc *src = GST_DXGI_SCREEN_CAP_SRC (bsrc);
+  RECT rect_dst;
+  GstCaps *caps = NULL;
+
+  HMONITOR hmonitor = _get_hmonitor (src);
+  if (!get_monitor_physical_size (hmonitor, &rect_dst)) {
+    GST_ELEMENT_ERROR (src, RESOURCE, NOT_FOUND,
+        ("Specified monitor with index %d not found", src->monitor), (NULL));
+    return NULL;
+  }
+
+  src->screen_rect = rect_dst;
+  if (src->capture_w && src->capture_h &&
+      src->capture_x + src->capture_w <= RECT_WIDTH (rect_dst) &&
+      src->capture_y + src->capture_h <= RECT_HEIGHT (rect_dst)) {
+    rect_dst.left = src->capture_x;
+    rect_dst.top = src->capture_y;
+    rect_dst.right = src->capture_x + src->capture_w;
+    rect_dst.bottom = src->capture_y + src->capture_h;
+  } else {
+    /* Default values */
+    src->capture_x = src->capture_y = 0;
+    src->capture_w = src->capture_h = 0;
+  }
+
+  /* The desktop image is always in the DXGI_FORMAT_B8G8R8A8_UNORM format. */
+  GST_DEBUG_OBJECT (src, "get_cap rect: %ld, %ld, %ld, %ld", rect_dst.left,
+      rect_dst.top, rect_dst.right, rect_dst.bottom);
+
+  caps =
+      gst_caps_new_simple ("video/x-raw", "format", G_TYPE_STRING, "BGRA",
+      "width", G_TYPE_INT, RECT_WIDTH (rect_dst),
+      "height", G_TYPE_INT, RECT_HEIGHT (rect_dst),
+      "framerate", GST_TYPE_FRACTION_RANGE, 1, 1, G_MAXINT,
+      1, "pixel-aspect-ratio", GST_TYPE_FRACTION, 1, 1, NULL);
+
+  if (filter) {
+    GstCaps *tmp =
+        gst_caps_intersect_full (filter, caps, GST_CAPS_INTERSECT_FIRST);
+    gst_caps_unref (caps);
+    caps = tmp;
+  }
+  return caps;
+}
+
+static gboolean
+gst_dxgi_screen_cap_src_start (GstBaseSrc * bsrc)
+{
+  GstDXGIScreenCapSrc *src = GST_DXGI_SCREEN_CAP_SRC (bsrc);
+  HMONITOR hmonitor = _get_hmonitor (src);
+  if (NULL == hmonitor) {
+    GST_ELEMENT_ERROR (src, RESOURCE, NOT_FOUND,
+        ("Specified monitor with index %d not found", src->monitor), (NULL));
+    return FALSE;
+  }
+  src->dxgi_capture = dxgicap_new (hmonitor, src);
+
+  if (NULL == src->dxgi_capture) {
+    GST_ELEMENT_ERROR (src, RESOURCE, NOT_FOUND,
+        ("Specified monitor with index %d not found", src->monitor), (NULL));
+    return FALSE;
+  }
+  dxgicap_start (src->dxgi_capture);
+
+  src->frame_number = -1;
+  return TRUE;
+}
+
+static gboolean
+gst_dxgi_screen_cap_src_stop (GstBaseSrc * bsrc)
+{
+  GstDXGIScreenCapSrc *src = GST_DXGI_SCREEN_CAP_SRC (bsrc);
+  dxgicap_stop (src->dxgi_capture);
+  dxgicap_destory (src->dxgi_capture);
+  src->dxgi_capture = NULL;
+
+  return TRUE;
+}
+
+static gboolean
+gst_dxgi_screen_cap_src_unlock (GstBaseSrc * bsrc)
+{
+  GstDXGIScreenCapSrc *src = GST_DXGI_SCREEN_CAP_SRC (bsrc);
+
+  GST_OBJECT_LOCK (src);
+  if (src->clock_id) {
+    GST_DEBUG_OBJECT (src, "Waking up waiting clock");
+    gst_clock_id_unschedule (src->clock_id);
+  }
+  GST_OBJECT_UNLOCK (src);
+
+  return TRUE;
+}
+
+static GstFlowReturn
+gst_dxgi_screen_cap_src_fill (GstPushSrc * push_src, GstBuffer * buf)
+{
+  GstDXGIScreenCapSrc *src = GST_DXGI_SCREEN_CAP_SRC (push_src);
+  GstClock *clock;
+  GstClockTime buf_time, buf_dur;
+  guint64 frame_number;
+
+  if (G_UNLIKELY (!src->dxgi_capture)) {
+    GST_DEBUG_OBJECT (src, "format wasn't negotiated before create function");
+    return GST_FLOW_NOT_NEGOTIATED;
+  }
+
+  clock = gst_element_get_clock (GST_ELEMENT (src));
+  if (clock != NULL) {
+    GstClockTime time, base_time;
+
+    /* Calculate sync time. */
+
+    time = gst_clock_get_time (clock);
+    base_time = gst_element_get_base_time (GST_ELEMENT (src));
+    buf_time = time - base_time;
+
+    if (src->rate_numerator) {
+      frame_number = gst_util_uint64_scale (buf_time,
+          src->rate_numerator, GST_SECOND * src->rate_denominator);
+    } else {
+      frame_number = -1;
+    }
+  } else {
+    buf_time = GST_CLOCK_TIME_NONE;
+    frame_number = -1;
+  }
+
+  if (frame_number != -1 && frame_number == src->frame_number) {
+    GstClockID id;
+    GstClockReturn ret;
+
+    /* Need to wait for the next frame */
+    frame_number += 1;
+
+    /* Figure out what the next frame time is */
+    buf_time = gst_util_uint64_scale (frame_number,
+        src->rate_denominator * GST_SECOND, src->rate_numerator);
+
+    id = gst_clock_new_single_shot_id (clock,
+        buf_time + gst_element_get_base_time (GST_ELEMENT (src)));
+    GST_OBJECT_LOCK (src);
+    src->clock_id = id;
+    GST_OBJECT_UNLOCK (src);
+
+    GST_DEBUG_OBJECT (src, "Waiting for next frame time %" G_GUINT64_FORMAT,
+        buf_time);
+    ret = gst_clock_id_wait (id, NULL);
+
+    GST_OBJECT_LOCK (src);
+    gst_clock_id_unref (id);
+    src->clock_id = NULL;
+    GST_OBJECT_UNLOCK (src);
+
+    if (ret == GST_CLOCK_UNSCHEDULED) {
+      /* Got woken up by the unlock function */
+      if (clock) {
+        gst_object_unref (clock);
+      }
+      return GST_FLOW_FLUSHING;
+    }
+
+    /* Duration is a complete 1/fps frame duration */
+    buf_dur =
+        gst_util_uint64_scale_int (GST_SECOND, src->rate_denominator,
+        src->rate_numerator);
+  } else if (frame_number != -1) {
+    GstClockTime next_buf_time;
+
+    GST_DEBUG_OBJECT (src, "No need to wait for next frame time %"
+        G_GUINT64_FORMAT " next frame = %" G_GINT64_FORMAT
+        " prev = %" G_GINT64_FORMAT, buf_time, frame_number, src->frame_number);
+    next_buf_time =
+        gst_util_uint64_scale (frame_number + 1,
+        src->rate_denominator * GST_SECOND, src->rate_numerator);
+    /* Frame duration is from now until the next expected capture time */
+    buf_dur = next_buf_time - buf_time;
+  } else {
+    buf_dur = GST_CLOCK_TIME_NONE;
+  }
+  src->frame_number = frame_number;
+
+  if (clock) {
+    gst_object_unref (clock);
+  }
+
+  /* Get the latest desktop frame. */
+  if (dxgicap_acquire_next_frame (src->dxgi_capture, src->show_cursor, 0)) {
+    /* Copy the latest desktop frame to the video frame. */
+    if (dxgicap_copy_buffer (src->dxgi_capture, src->show_cursor,
+            &src->src_rect, &src->video_info, buf)) {
+      GST_BUFFER_TIMESTAMP (buf) = buf_time;
+      GST_BUFFER_DURATION (buf) = buf_dur;
+      return GST_FLOW_OK;
+    }
+  }
+  return GST_FLOW_ERROR;
+}
+
+static HMONITOR
+_get_hmonitor (GstDXGIScreenCapSrc * src)
+{
+  HMONITOR hmonitor = NULL;
+  GST_DEBUG_OBJECT (src, "device_name:%s", GST_STR_NULL (src->device_name));
+  if (NULL != src->device_name) {
+    hmonitor = get_hmonitor_by_device_name (src->device_name);
+  }
+  if (NULL == hmonitor && DEFAULT_MONITOR != src->monitor) {
+    hmonitor = get_hmonitor_by_index (src->monitor);
+  }
+  if (NULL == hmonitor) {
+    hmonitor = get_hmonitor_primary ();
+  }
+  return hmonitor;
+}

sys/winscreencap/gstdxgiscreencapsrc.h

@@ -0,0 +1,32 @@
+/* GStreamer
+ * Copyright (C) 2019 OKADA Jun-ichi <okada@abt.jp>
+ *
+ * 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_DXGI_SCREEN_CAP_SRC_H__
+#define __GST_DXGI_SCREEN_CAP_SRC_H__
+
+#include <windows.h>
+#include <gst/gst.h>
+#include <gst/base/gstpushsrc.h>
+
+G_BEGIN_DECLS
+#define GST_TYPE_DXGI_SCREEN_CAP_SRC  (gst_dxgi_screen_cap_src_get_type())
+G_DECLARE_FINAL_TYPE (GstDXGIScreenCapSrc, gst_dxgi_screen_cap_src, GST,
+    DXGI_SCREEN_CAP_SRC, GstPushSrc);
+
+G_END_DECLS
+#endif /* __GST_DXGI_SCREEN_CAP_SRC_H__ */

sys/winscreencap/gstwinscreencap.c

@@ -20,11 +20,15 @@
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
-
 #include "gstwinscreencap.h"
 #include "gstgdiscreencapsrc.h"
 #include "gstdx9screencapsrc.h"
 
+#ifdef HAVE_DXGI_CAP
+#include <versionhelpers.h>
+#include "gstdxgiscreencapsrc.h"
+#endif
+
 static BOOL CALLBACK
 _diplay_monitor_enum (HMONITOR hMon, HDC hdc, LPRECT rect, LPARAM param)
 {
@@ -66,6 +70,15 @@ plugin_init (GstPlugin * plugin)
           GST_RANK_NONE, GST_TYPE_DX9SCREENCAPSRC)) {
     return FALSE;
   }
+#ifdef HAVE_DXGI_CAP
+  if (IsWindows8OrGreater ()) {
+    /* dxgiscreencapsrc is needs Windows8 or later. */
+    if (!gst_element_register (plugin, "dxgiscreencapsrc",
+            GST_RANK_NONE, GST_TYPE_DXGI_SCREEN_CAP_SRC)) {
+      return FALSE;
+    }
+  }
+#endif
 
   return TRUE;
 }

sys/winscreencap/meson.build

@@ -4,23 +4,47 @@ winscreencap_sources = [
   'gstwinscreencap.c',
 ]
 
+have_dxgi = false
+dxgi_c_args = []
+dxgiscreencap_sources = []
+dxgi_dep = []
+
 if host_system != 'windows' or get_option('winscreencap').disabled()
   subdir_done()
 endif
 
 d3d_dep = cc.find_library('d3d9', required : get_option('winscreencap'))
 gdi_dep = cc.find_library('gdi32', required : get_option('winscreencap'))
+d3d11_dep = cc.find_library('d3d11', required : false)
+dxgi_lib_dep = cc.find_library('dxgi', required : false)
+d3d_compile_dep = cc.find_library('d3dcompiler', required : false)
+windowscodecs_dep = cc.find_library('windowscodecs',  required : false)
+dxguid_dep = cc.find_library('dxguid',  required : false) 
+
+have_d3d11_h = cc.has_header('d3d11.h')
+have_dxgi_h = cc.has_header('dxgi1_2.h')
+have_d3dcompiler_h = cc.has_header('d3dcompiler.h')
+have_versionhelpers_h = cc.has_header('versionhelpers.h')
+
 have_d3d9_h = cc.has_header('d3d9.h')
 if not have_d3d9_h and get_option('winscreencap').enabled()
   error('winscreencap plugin enabled but d3d9.h not found')
 endif
 
+have_dxgi = d3d11_dep.found() and dxgi_lib_dep.found() and d3d_compile_dep.found() and windowscodecs_dep.found() and dxguid_dep.found() and have_d3d11_h and have_dxgi_h and have_d3dcompiler_h and have_versionhelpers_h
+
+if have_dxgi
+  dxgi_c_args += ['-DHAVE_DXGI_CAP']
+  dxgiscreencap_sources += ['dxgicapture.c', 'gstdxgiscreencapsrc.c']
+  dxgi_dep += [d3d11_dep, dxgi_lib_dep, d3d_compile_dep, windowscodecs_dep, dxguid_dep]
+endif
+
 if d3d_dep.found() and gdi_dep.found() and have_d3d9_h
   gstwinscreencap = library('gstwinscreencap',
-    winscreencap_sources,
+    winscreencap_sources + dxgiscreencap_sources,
-    c_args : gst_plugins_bad_args,
+    c_args : gst_plugins_bad_args + dxgi_c_args,
     include_directories : [configinc],
-    dependencies : [gstbase_dep, gstvideo_dep, d3d_dep, gdi_dep],
+    dependencies : [gstbase_dep, gstvideo_dep, d3d_dep, gdi_dep] + dxgi_dep,
     install : true,
     install_dir : plugins_install_dir,
   )