video-timer: add a test case for display at a constant frame rate

Add a test case that simulates the timing operaton that goes on
when showing a constant frame rate stream like a video - each
frame is shown at the VBlank interval that is closest to when it
would ideally be timed.

https://bugzilla.gnome.org/show_bug.cgi?id=685460
This commit is contained in:
Owen W. Taylor 2012-11-15 17:39:30 -05:00
parent fb44ea8a85
commit e77a96a0ea
2 changed files with 335 additions and 0 deletions

View File

@ -30,6 +30,7 @@ noinst_PROGRAMS = $(TEST_PROGS) \
simple \
flicker \
print-editor \
video-timer \
testaccel \
testadjustsize \
testappchooser \
@ -156,6 +157,7 @@ flicker_DEPENDENCIES = $(TEST_DEPS)
motion_compression_DEPENDENCIES = $(TEST_DEPS)
simple_DEPENDENCIES = $(TEST_DEPS)
print_editor_DEPENDENCIES = $(TEST_DEPS)
video_timer_DEPENDENCIES = $(TEST_DEPS)
testheightforwidth_DEPENDENCIES = $(TEST_DEPS)
testicontheme_DEPENDENCIES = $(TEST_DEPS)
testiconview_DEPENDENCIES = $(TEST_DEPS)
@ -258,6 +260,11 @@ animated_resizing_SOURCES = \
variable.c \
variable.h
video_timer_SOURCES = \
video-timer.c \
variable.c \
variable.h
testboxcss_SOURCES = \
testboxcss.c \
prop-editor.c

328
tests/video-timer.c Normal file
View File

@ -0,0 +1,328 @@
#include <math.h>
#include <gtk/gtk.h>
#include "variable.h"
typedef struct {
gdouble angle;
gint64 stream_time;
gint64 clock_time;
gint64 frame_counter;
} FrameData;
static FrameData *displayed_frame;
static GtkWidget *window;
static GList *past_frames;
static Variable latency_error = VARIABLE_INIT;
static int dropped_frames = 0;
static int n_frames = 0;
static int fps = 24;
/* Thread-safe frame queue */
#define MAX_QUEUE_LENGTH 5
static GQueue *frame_queue;
static GMutex frame_mutex;
static GCond frame_cond;
static void
queue_frame (FrameData *frame_data)
{
g_mutex_lock (&frame_mutex);
while (frame_queue->length == MAX_QUEUE_LENGTH)
g_cond_wait (&frame_cond, &frame_mutex);
g_queue_push_tail (frame_queue, frame_data);
g_mutex_unlock (&frame_mutex);
}
static FrameData *
unqueue_frame (void)
{
FrameData *frame_data;
g_mutex_lock (&frame_mutex);
if (frame_queue->length > 0)
{
frame_data = g_queue_pop_head (frame_queue);
g_cond_signal (&frame_cond);
}
else
{
frame_data = NULL;
}
g_mutex_unlock (&frame_mutex);
return frame_data;
}
static FrameData *
peek_pending_frame (void)
{
FrameData *frame_data;
g_mutex_lock (&frame_mutex);
if (frame_queue->head)
frame_data = frame_queue->head->data;
else
frame_data = NULL;
g_mutex_unlock (&frame_mutex);
return frame_data;
}
static FrameData *
peek_next_frame (void)
{
FrameData *frame_data;
g_mutex_lock (&frame_mutex);
if (frame_queue->head && frame_queue->head->next)
frame_data = frame_queue->head->next->data;
else
frame_data = NULL;
g_mutex_unlock (&frame_mutex);
return frame_data;
}
/* Frame producer thread */
static gpointer
create_frames_thread (gpointer data)
{
int frame_count = 0;
while (TRUE)
{
FrameData *frame_data = g_slice_new0 (FrameData);
frame_data->angle = 2 * M_PI * (frame_count % fps) / (double)fps;
frame_data->stream_time = (G_GINT64_CONSTANT (1000000) * frame_count) / fps;
queue_frame (frame_data);
frame_count++;
}
return NULL;
}
/* Clock management */
#define PRE_BUFFER_TIME 500000
static gint64 start_time;
static gint64
stream_time_to_clock_time (gint64 stream_time)
{
return start_time + stream_time + PRE_BUFFER_TIME;
}
/* Drawing */
static void
on_window_draw (GtkWidget *widget,
cairo_t *cr)
{
GdkRectangle allocation;
double cx, cy, r;
cairo_set_source_rgb (cr, 1., 1., 1.);
cairo_paint (cr);
cairo_set_source_rgb (cr, 0., 0., 0.);
gtk_widget_get_allocation (widget, &allocation);
cx = allocation.width / 2.;
cy = allocation.height / 2.;
r = MIN (allocation.width, allocation.height) / 2.;
cairo_arc (cr, cx, cy, r,
0, 2 * M_PI);
cairo_stroke (cr);
if (displayed_frame)
{
cairo_move_to (cr, cx, cy);
cairo_line_to (cr,
cx + r * cos(displayed_frame->angle - M_PI / 2),
cy + r * sin(displayed_frame->angle - M_PI / 2));
cairo_stroke (cr);
if (displayed_frame->frame_counter == 0)
{
GdkFrameClock *frame_clock = gtk_widget_get_frame_clock (window);
GdkFrameHistory *history = gdk_frame_clock_get_history (frame_clock);
displayed_frame->frame_counter = gdk_frame_history_get_frame_counter (history);
}
}
}
static void
collect_old_frames (void)
{
GdkFrameClock *frame_clock = gtk_widget_get_frame_clock (window);
GdkFrameHistory *history = gdk_frame_clock_get_history (frame_clock);
GList *l, *l_next;
for (l = past_frames; l; l = l_next)
{
FrameData *frame_data = l->data;
gboolean remove = FALSE;
l_next = l->next;
GdkFrameTimings *timings = gdk_frame_history_get_timings (history,
frame_data->frame_counter);
if (timings == NULL)
{
remove = TRUE;
}
else if (gdk_frame_timings_get_complete (timings))
{
gint64 presentation_time = gdk_frame_timings_get_presentation_time (timings);
if (presentation_time)
variable_add (&latency_error,
presentation_time - frame_data->clock_time);
remove = TRUE;
}
if (remove)
{
past_frames = g_list_delete_link (past_frames, l);
g_slice_free (FrameData, frame_data);
}
}
}
static void
print_statistics (void)
{
gint64 now = g_get_monotonic_time ();
static gint64 last_print_time = 0;
if (last_print_time == 0)
last_print_time = now;
else if (now -last_print_time > 5000000)
{
g_print ("dropped_frames: %d/%d\n",
dropped_frames, n_frames);
g_print ("collected_frames: %g/%d\n",
latency_error.weight, n_frames);
g_print ("latency_error: %g +/- %g\n",
variable_mean (&latency_error),
variable_standard_deviation (&latency_error));
variable_reset (&latency_error);
dropped_frames = 0;
n_frames = 0;
last_print_time = now;
}
}
static void
on_update (GdkFrameClock *frame_clock,
gpointer data)
{
GdkFrameTimings *timings = gdk_frame_clock_get_current_frame_timings (frame_clock);
gint64 frame_time = gdk_frame_timings_get_frame_time (timings);
gint64 predicted_presentation_time = gdk_frame_timings_get_predicted_presentation_time (timings);
gint64 refresh_interval;
FrameData *pending_frame;
if (start_time == 0)
start_time = frame_time;
gdk_frame_clock_get_refresh_info (frame_clock, frame_time,
&refresh_interval, NULL);
pending_frame = peek_pending_frame ();
if (stream_time_to_clock_time (pending_frame->stream_time)
< predicted_presentation_time + refresh_interval / 2)
{
while (TRUE)
{
FrameData *next_frame = peek_next_frame ();
if (next_frame &&
stream_time_to_clock_time (next_frame->stream_time)
< predicted_presentation_time + refresh_interval / 2)
{
g_slice_free (FrameData, unqueue_frame ());
n_frames++;
dropped_frames++;
pending_frame = next_frame;
}
else
break;
}
if (displayed_frame)
past_frames = g_list_prepend (past_frames, displayed_frame);
n_frames++;
displayed_frame = unqueue_frame ();
displayed_frame->clock_time = stream_time_to_clock_time (displayed_frame->stream_time);
displayed_frame->frame_counter = gdk_frame_timings_get_frame_counter (timings);
collect_old_frames ();
print_statistics ();
gtk_widget_queue_draw (window);
}
gdk_frame_clock_request_phase (frame_clock, GDK_FRAME_CLOCK_PHASE_UPDATE);
}
static GOptionEntry options[] = {
{ "fps", 'f', 0, G_OPTION_ARG_INT, &fps, "Frame rate", "FPS" },
{ NULL }
};
int
main(int argc, char **argv)
{
GError *error = NULL;
GdkFrameClock *frame_clock;
if (!gtk_init_with_args (&argc, &argv, "",
options, NULL, &error))
{
g_printerr ("Option parsing failed: %s\n", error->message);
return 1;
}
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_widget_set_app_paintable (window, TRUE);
gtk_window_set_default_size (GTK_WINDOW (window), 300, 300);
g_signal_connect (window, "draw",
G_CALLBACK (on_window_draw), NULL);
g_signal_connect (window, "destroy",
G_CALLBACK (gtk_main_quit), NULL);
gtk_widget_show (window);
frame_queue = g_queue_new ();
g_mutex_init (&frame_mutex);
g_cond_init (&frame_cond);
g_thread_new ("Create Frames", create_frames_thread, NULL);
frame_clock = gtk_widget_get_frame_clock (window);
g_signal_connect (frame_clock, "update",
G_CALLBACK (on_update), NULL);
gdk_frame_clock_request_phase (frame_clock, GDK_FRAME_CLOCK_PHASE_UPDATE);
gtk_main ();
return 0;
}