thumbnailer/swfdec-thumbnailer.c | 54 ++++++++++++++++++++++++++-------------
1 file changed, 36 insertions(+), 18 deletions(-)
New commits:
commit 278f254d8fdd6c6e9f48203949f1da373f62cab4
Author: Pekka Lampila <pekka.lampila at iki.fi>
Date: Thu Nov 8 14:08:11 2007 +0200
Make boring image test in the thumbnailer better
Now it doesn't consider areas which were left transparent to center the
image
diff --git a/thumbnailer/swfdec-thumbnailer.c b/thumbnailer/swfdec-thumbnailer.c
index d4d1770..ba35869 100644
--- a/thumbnailer/swfdec-thumbnailer.c
+++ b/thumbnailer/swfdec-thumbnailer.c
@@ -32,32 +32,46 @@
* It does this by calculating the statistical variance of the
* black-and-white image */
static gboolean
-is_image_interesting (cairo_surface_t *surface)
+is_image_interesting (cairo_surface_t *surface, int x, int y, int width,
+ int height)
{
/* We're gonna assume 8-bit samples. If anyone uses anything different,
* it doesn't really matter cause it's gonna be ugly anyways */
- int rowstride = cairo_image_surface_get_stride (surface);
- int height = cairo_image_surface_get_height (surface);
- guchar* buffer = cairo_image_surface_get_data (surface);
- int num_samples = (rowstride * height);
- int i;
- float x_bar = 0.0f;
- float variance = 0.0f;
-
- /* FIXME: If this proves to be a performance issue, this function
- * can be modified to perhaps only check 3 rows. I doubt this'll
- * be a problem though. */
+ int stride, rowcount, num_samples, i, j;
+ guchar *buffer;
+ float x_bar, variance;
+
+ g_return_val_if_fail (surface != NULL, FALSE);
+ g_return_val_if_fail (x + width <= cairo_image_surface_get_width
(surface),
+ FALSE);
+ g_return_val_if_fail (y + height <= cairo_image_surface_get_height
(surface),
+ FALSE);
+
+ stride = cairo_image_surface_get_stride (surface);
+ rowcount = cairo_image_surface_get_height (surface);
+ buffer = cairo_image_surface_get_data (surface);
+
+ x *= stride / cairo_image_surface_get_width (surface);
+ width *= stride / cairo_image_surface_get_width (surface);
+
+ num_samples = width * height;
/* Iterate through the image to calculate x-bar */
- for (i = 0; i < num_samples; i++) {
- x_bar += (float) buffer[i];
+ x_bar = 0.0f;
+ for (i = y; i < y + height; i++) {
+ for (j = x; j < x + width; j++) {
+ x_bar += (float) buffer[i * stride + j];
+ }
}
x_bar /= ((float) num_samples);
/* Calculate the variance */
- for (i = 0; i < num_samples; i++) {
- float tmp = ((float) buffer[i] - x_bar);
- variance += tmp * tmp;
+ variance = 0.0f;
+ for (i = y; i < y + height; i++) {
+ for (j = x; j < x + width; j++) {
+ float tmp = ((float) buffer[i * stride + j] - x_bar);
+ variance += tmp * tmp;
+ }
}
variance /= ((float) (num_samples - 1));
@@ -179,7 +193,11 @@ main (int argc, char **argv)
// render the image
swfdec_player_render (player, cr, x, y, w, h);
- for (try = 0; try < 10 && time_left &&
!is_image_interesting (surface); try++) {
+ for (try = 0; try < 10 && time_left; try++)
+ {
+ if (is_image_interesting (surface, (size - w * scale) / 2,
+ (size - h * scale) / 2, w * scale, h * scale))
+ break;
time_left = advance (player, timer, 1000);
swfdec_player_render (player, cr, x, y, w, h);
}