[x264-devel] commit: Display SSIM measurement in db as well (Jason Garrett-Glaser )

[git at videolan.org]

x264 | branch: stable | Jason Garrett-Glaser <darkshikari at gmail.com> | Wed Jun  2 15:47:26 2010 -0700| [8a964bce8dc7b874b962cee41d17a66c7beb75b3] | committer: Jason Garrett-Glaser 

Display SSIM measurement in db as well

> http://git.videolan.org/gitweb.cgi/x264.git/?a=commit;h=8a964bce8dc7b874b962cee41d17a66c7beb75b3
---

 encoder/encoder.c |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/encoder/encoder.c b/encoder/encoder.c
index 9c89eeb..238f2b6 100644
--- a/encoder/encoder.c
+++ b/encoder/encoder.c
@@ -58,6 +58,11 @@ static float x264_psnr( int64_t i_sqe, int64_t i_size )
     return -10.0 * log10( f_mse );
 }
 
+static float x264_ssim( float ssim )
+{
+    return -10.0 * log10( 1 - ssim );
+}
+
 static void x264_frame_dump( x264_t *h )
 {
     FILE *f = fopen( h->param.psz_dump_yuv, "r+b" );
@@ -3069,9 +3074,8 @@ void    x264_encoder_close  ( x264_t *h )
 
         if( h->param.analyse.b_ssim )
         {
-            x264_log( h, X264_LOG_INFO,
-                      "SSIM Mean Y:%.7f\n",
-                      SUM3( h->stat.f_ssim_mean_y ) / i_count );
+            float ssim = SUM3( h->stat.f_ssim_mean_y ) / i_count;
+            x264_log( h, X264_LOG_INFO, "SSIM Mean Y:%.7f (%6.3fdb)\n", ssim, x264_ssim( ssim ) );
         }
         if( h->param.analyse.b_psnr )
         {