[Spice-devel] [spice v4] server: Provide a framerate estimate based on the initial frames

[Francois Gouget]

This way the video encoder can actually count on a real estimate when
it is initializing.

Signed-off-by: Francois Gouget <fgouget at codeweavers.com>
---
 server/display-channel.h |  1 +
 server/red_worker.c      | 22 ++++++++++++++++++----
 server/stream.h          |  1 +
 3 files changed, 20 insertions(+), 4 deletions(-)

Check that duration is not 0 and that we don't exceed MAX_FPS.

diff --git a/server/display-channel.h b/server/display-channel.h
index a9ae40a..23d7a05 100644
--- a/server/display-channel.h
+++ b/server/display-channel.h
@@ -152,6 +152,7 @@ struct Drawable {
     Ring glz_ring;
 
     red_time_t creation_time;
+    red_time_t first_frame_time;
     int frames_count;
     int gradual_frames_count;
     int last_gradual_frame;
diff --git a/server/red_worker.c b/server/red_worker.c
index 165e4c0..23834d3 100644
--- a/server/red_worker.c
+++ b/server/red_worker.c
@@ -984,6 +984,7 @@ static void display_stream_trace_add_drawable(DisplayChannel *display, Drawable
 
     trace = &display->items_trace[display->next_item_trace++ & ITEMS_TRACE_MASK];
     trace->time = item->creation_time;
+    trace->first_frame_time = item->first_frame_time;
     trace->frames_count = item->frames_count;
     trace->gradual_frames_count = item->gradual_frames_count;
     trace->last_gradual_frame = item->last_gradual_frame;
@@ -1772,7 +1773,16 @@ static void display_channel_create_stream(DisplayChannel *display, Drawable *dra
     SpiceBitmap *bitmap = &drawable->red_drawable->u.copy.src_bitmap->u.bitmap;
     stream->top_down = !!(bitmap->flags & SPICE_BITMAP_FLAGS_TOP_DOWN);
     drawable->stream = stream;
-    stream->input_fps = MAX_FPS;
+    /* Provide an fps estimate the video encoder can use when initializing
+     * based on the frames that lead to the creation of the stream. Round to
+     * the nearest integer, for instance 24 for 23.976.
+     */
+    uint64_t duration = drawable->creation_time - drawable->first_frame_time;
+    if (duration > (uint64_t)drawable->frames_count * 1000 * 1000 * 1000 / MAX_FPS) {
+        stream->input_fps = ((uint64_t)drawable->frames_count * 1000 * 1000 * 1000 + duration / 2) / duration;
+    } else {
+        stream->input_fps = MAX_FPS;
+    }
     stream->num_input_frames = 0;
     stream->input_fps_start_time = drawable->creation_time;
     display->streams_size_total += stream->width * stream->height;
@@ -1780,10 +1790,10 @@ static void display_channel_create_stream(DisplayChannel *display, Drawable *dra
     FOREACH_DCC(display, dcc_ring_item, next, dcc) {
         dcc_create_stream(dcc, stream);
     }
-    spice_debug("stream %d %dx%d (%d, %d) (%d, %d)",
+    spice_debug("stream %d %dx%d (%d, %d) (%d, %d) %u fps",
                 (int)(stream - display->streams_buf), stream->width,
                 stream->height, stream->dest_area.left, stream->dest_area.top,
-                stream->dest_area.right, stream->dest_area.bottom);
+                stream->dest_area.right, stream->dest_area.bottom, stream->input_fps);
     return;
 }
 
@@ -2009,11 +2019,13 @@ static int is_stream_start(Drawable *drawable)
 // returns whether a stream was created
 static int display_channel_stream_add_frame(DisplayChannel *display,
                                             Drawable *frame_drawable,
+                                            red_time_t first_frame_time,
                                             int frames_count,
                                             int gradual_frames_count,
                                             int last_gradual_frame)
 {
     update_copy_graduality(display, frame_drawable);
+    frame_drawable->first_frame_time = first_frame_time;
     frame_drawable->frames_count = frames_count + 1;
     frame_drawable->gradual_frames_count  = gradual_frames_count;
 
@@ -2074,6 +2086,7 @@ static void display_channel_stream_maintenance(DisplayChannel *display,
                                  FALSE);
         if (is_next_frame != STREAM_FRAME_NONE) {
             display_channel_stream_add_frame(display, candidate,
+                                             prev->first_frame_time,
                                              prev->frames_count,
                                              prev->gradual_frames_count,
                                              prev->last_gradual_frame);
@@ -2235,6 +2248,7 @@ static void red_use_stream_trace(DisplayChannel *display, Drawable *drawable)
                                        &trace->dest_area, trace->time, NULL, FALSE) !=
                                        STREAM_FRAME_NONE) {
             if (display_channel_stream_add_frame(display, drawable,
+                                                 trace->first_frame_time,
                                                  trace->frames_count,
                                                  trace->gradual_frames_count,
                                                  trace->last_gradual_frame)) {
@@ -2664,7 +2678,7 @@ static Drawable *get_drawable(RedWorker *worker, uint8_t effect, RedDrawable *re
 
     bzero(drawable, sizeof(Drawable));
     drawable->refs = 1;
-    drawable->creation_time = red_get_monotonic_time();
+    drawable->creation_time = drawable->first_frame_time = red_get_monotonic_time();
     ring_item_init(&drawable->list_link);
     ring_item_init(&drawable->surface_list_link);
     ring_item_init(&drawable->tree_item.base.siblings_link);
diff --git a/server/stream.h b/server/stream.h
index f77fa96..d9f1a66 100644
--- a/server/stream.h
+++ b/server/stream.h
@@ -108,6 +108,7 @@ StreamClipItem *stream_clip_item_new(DisplayChannelClient* dcc,
 
 typedef struct ItemTrace {
     red_time_t time;
+    red_time_t first_frame_time;
     int frames_count;
     int gradual_frames_count;
     int last_gradual_frame;
-- 
2.6.2