From 20dbf18596feafc17341c330d573807b4940a636 Mon Sep 17 00:00:00 2001

From: Olivier Fourdan <ofourdan@redhat.com>

Date: Thu, 22 Nov 2018 11:59:10 +0100

Subject: [PATCH 04/12] screen-cast-src: Add VideoCrop support

To be able to cast windows, which by definition can change in size

dynamically, we need a way to specify the video crop meta to adjust to

the window size whenever it changes.

Add VideoCrop support with a new optional hook `get_videocrop()` in the

`ScreenCastStreamSrcClass` which, if defined, can let the child specify

a rectangle for the video cropping area.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/306

(cherry picked from commit f64eba57ce3fb67a65a5c5755469d4b97067030f)

---

 src/backends/meta-screen-cast-stream-src.c | 56 ++++++++++++++++++++--

 src/backends/meta-screen-cast-stream-src.h |  3 ++

 2 files changed, 55 insertions(+), 4 deletions(-)

diff --git a/src/backends/meta-screen-cast-stream-src.c b/src/backends/meta-screen-cast-stream-src.c

index 0c4f33b..673a464 100644

--- a/src/backends/meta-screen-cast-stream-src.c

+++ b/src/backends/meta-screen-cast-stream-src.c

@@ -91,6 +91,9 @@ typedef struct _MetaScreenCastStreamSrcPrivate

   struct spa_video_info_raw video_format;

   uint64_t last_frame_timestamp_us;

+

+  int stream_width;

+  int stream_height;

 } MetaScreenCastStreamSrcPrivate;

 static void

@@ -117,6 +120,19 @@ meta_screen_cast_stream_src_get_specs (MetaScreenCastStreamSrc *src,

   klass->get_specs (src, width, height, frame_rate);

 }

+static gboolean

+meta_screen_cast_stream_src_get_videocrop (MetaScreenCastStreamSrc *src,

+                                           MetaRectangle           *crop_rect)

+{

+  MetaScreenCastStreamSrcClass *klass =

+    META_SCREEN_CAST_STREAM_SRC_GET_CLASS (src);

+

+  if (klass->get_videocrop)

+    return klass->get_videocrop (src, crop_rect);

+

+  return FALSE;

+}

+

 static void

 meta_screen_cast_stream_src_record_frame (MetaScreenCastStreamSrc *src,

                                           uint8_t                 *data)

@@ -132,8 +148,10 @@ meta_screen_cast_stream_src_maybe_record_frame (MetaScreenCastStreamSrc *src)

 {

   MetaScreenCastStreamSrcPrivate *priv =

     meta_screen_cast_stream_src_get_instance_private (src);

+  MetaRectangle crop_rect;

   struct pw_buffer *buffer;

   struct spa_buffer *spa_buffer;

+  struct spa_meta_video_crop *spa_meta_video_crop;

   uint8_t *map = NULL;

   uint8_t *data;

   uint64_t now_us;

@@ -182,6 +200,27 @@ meta_screen_cast_stream_src_maybe_record_frame (MetaScreenCastStreamSrc *src)

     }

   meta_screen_cast_stream_src_record_frame (src, data);

+

+  /* Update VideoCrop if needed */

+  spa_meta_video_crop = spa_buffer_find_meta (spa_buffer, priv->pipewire_type->meta.VideoCrop);

+  if (spa_meta_video_crop)

+    {

+      if (meta_screen_cast_stream_src_get_videocrop (src, &crop_rect))

+        {

+          spa_meta_video_crop->x = crop_rect.x;

+          spa_meta_video_crop->y = crop_rect.y;

+          spa_meta_video_crop->width = crop_rect.width;

+          spa_meta_video_crop->height = crop_rect.height;

+        }

+      else

+        {

+          spa_meta_video_crop->x = 0;

+          spa_meta_video_crop->y = 0;

+          spa_meta_video_crop->width = priv->stream_width;

+          spa_meta_video_crop->height = priv->stream_height;

+        }

+    }

+

   priv->last_frame_timestamp_us = now_us;

   if (map)

@@ -275,7 +314,7 @@ on_stream_format_changed (void                 *data,

   uint8_t params_buffer[1024];

   int32_t width, height, stride, size;

   struct spa_pod_builder pod_builder;

-  const struct spa_pod *params[1];

+  const struct spa_pod *params[2];

   const int bpp = 4;

   if (!format)

@@ -303,6 +342,12 @@ on_stream_format_changed (void                 *data,

     ":", pipewire_type->param_buffers.buffers, "iru", 16, PROP_RANGE (2, 16),

     ":", pipewire_type->param_buffers.align, "i", 16);

+  params[1] = spa_pod_builder_object (

+    &pod_builder,

+    pipewire_type->param.idMeta, pipewire_type->param_meta.Meta,

+    ":", pipewire_type->param_meta.type, "I", pipewire_type->meta.VideoCrop,

+    ":", pipewire_type->param_meta.size, "i", sizeof (struct spa_meta_video_crop));

+

   pw_stream_finish_format (priv->pipewire_stream, 0,

                            params, G_N_ELEMENTS (params));

 }

@@ -325,7 +370,6 @@ create_pipewire_stream (MetaScreenCastStreamSrc  *src,

     SPA_POD_BUILDER_INIT (buffer, sizeof (buffer));

   MetaSpaType *spa_type = &priv->spa_type;

   struct pw_type *pipewire_type = priv->pipewire_type;

-  int width, height;

   float frame_rate;

   MetaFraction frame_rate_fraction;

   struct spa_fraction max_framerate;

@@ -344,7 +388,10 @@ create_pipewire_stream (MetaScreenCastStreamSrc  *src,

       return NULL;

     }

-  meta_screen_cast_stream_src_get_specs (src, &width, &height, &frame_rate);

+  meta_screen_cast_stream_src_get_specs (src,

+                                         &priv->stream_width,

+                                         &priv->stream_height,

+                                         &frame_rate);

   frame_rate_fraction = meta_fraction_from_double (frame_rate);

   min_framerate = SPA_FRACTION (1, 1);

@@ -357,7 +404,8 @@ create_pipewire_stream (MetaScreenCastStreamSrc  *src,

     "I", spa_type->media_type.video,

     "I", spa_type->media_subtype.raw,

     ":", spa_type->format_video.format, "I", spa_type->video_format.BGRx,

-    ":", spa_type->format_video.size, "R", &SPA_RECTANGLE (width, height),

+    ":", spa_type->format_video.size, "R", &SPA_RECTANGLE (priv->stream_width,

+                                                           priv->stream_height),

     ":", spa_type->format_video.framerate, "F", &SPA_FRACTION (0, 1),

     ":", spa_type->format_video.max_framerate, "Fru", &max_framerate,

                                                       PROP_RANGE (&min_framerate,

diff --git a/src/backends/meta-screen-cast-stream-src.h b/src/backends/meta-screen-cast-stream-src.h

index c7ac57b..f3b3fd7 100644

--- a/src/backends/meta-screen-cast-stream-src.h

+++ b/src/backends/meta-screen-cast-stream-src.h

@@ -26,6 +26,7 @@

 #include <glib-object.h>

 #include "clutter/clutter.h"

+#include "meta/boxes.h"

 typedef struct _MetaScreenCastStream MetaScreenCastStream;

@@ -47,6 +48,8 @@ struct _MetaScreenCastStreamSrcClass

   void (* disable) (MetaScreenCastStreamSrc *src);

   void (* record_frame) (MetaScreenCastStreamSrc *src,

                          uint8_t                 *data);

+  gboolean (* get_videocrop) (MetaScreenCastStreamSrc *src,

+                              MetaRectangle           *crop_rect);

 };

 void meta_screen_cast_stream_src_maybe_record_frame (MetaScreenCastStreamSrc *src);

-- 

2.19.2