[Ffmpeg-cvslog] CVS: ffmpeg/libavcodec avcodec.h, 1.443, 1.444 motion_est.c, 1.119, 1.120 utils.c, 1.171, 1.172

Corey Hickey corey
Sun Jan 22 21:54:55 CET 2006


Update of /cvsroot/ffmpeg/ffmpeg/libavcodec
In directory mail:/var2/tmp/cvs-serv24568/libavcodec

Modified Files:
	avcodec.h motion_est.c utils.c 
Log Message:
sc_factor support for encoding.

Here's the description I'll add to the mplayer man page:
---
Causes frames with higher quantizers to be more likely to trigger a
scene change detection and make libavcodec use an I-frame (default: 1).
1-16 is a sane range.
Values between 2 and 6 may yield increasing PSNR (up to approximately
0.04 dB) and better placement of I-frames in high-motion scenes.
Higher values than 6 may give very slightly better PSNR (approximately
0.01 dB more than sc_factor=6), but noticably worse visual quality.
---

Original idea from Michael; patch by me.


Index: avcodec.h
===================================================================
RCS file: /cvsroot/ffmpeg/ffmpeg/libavcodec/avcodec.h,v
retrieving revision 1.443
retrieving revision 1.444
diff -u -d -r1.443 -r1.444
--- avcodec.h	14 Jan 2006 01:33:17 -0000	1.443
+++ avcodec.h	22 Jan 2006 20:54:51 -0000	1.444
@@ -1989,6 +1989,13 @@
      * - decoding: unused
      */
     int cutoff;
+
+    /**
+     * multiplied by qscale for each frame and added to scene_change_score
+     * - encoding: set by user.
+     * - decoding: unused
+     */
+    int scenechange_factor;
 } AVCodecContext;
 
 /**

Index: motion_est.c
===================================================================
RCS file: /cvsroot/ffmpeg/ffmpeg/libavcodec/motion_est.c,v
retrieving revision 1.119
retrieving revision 1.120
diff -u -d -r1.119 -r1.120
--- motion_est.c	12 Jan 2006 22:43:15 -0000	1.119
+++ motion_est.c	22 Jan 2006 20:54:52 -0000	1.120
@@ -1179,7 +1179,7 @@
             if (vard <= 64<<8 || vard < varc) { //FIXME
                 c->scene_change_score+= ff_sqrt(vard) - ff_sqrt(varc);
             }else{
-                c->scene_change_score+= s->qscale;
+                c->scene_change_score+= s->qscale * s->avctx->scenechange_factor;
             }
             return;
         }
@@ -1270,7 +1270,7 @@
         if (vard <= 64<<8 || vard < varc)
             c->scene_change_score+= ff_sqrt(vard) - ff_sqrt(varc);
         else
-            c->scene_change_score+= s->qscale;
+            c->scene_change_score+= s->qscale * s->avctx->scenechange_factor;
 
         if(mb_type == CANDIDATE_MB_TYPE_INTER){
             c->sub_motion_search(s, &mx, &my, dmin, 0, 0, 0, 16);
@@ -1291,7 +1291,7 @@
         if (vard <= 64<<8 || vard < varc)
             c->scene_change_score+= ff_sqrt(vard) - ff_sqrt(varc);
         else
-            c->scene_change_score+= s->qscale;
+            c->scene_change_score+= s->qscale * s->avctx->scenechange_factor;
 
         if (vard*2 + 200*256 > varc)
             mb_type|= CANDIDATE_MB_TYPE_INTRA;
@@ -1397,7 +1397,7 @@
         if (vard <= 64<<8 || vard < varc) { //FIXME
             c->scene_change_score+= ff_sqrt(vard) - ff_sqrt(varc);
         }else{
-            c->scene_change_score+= s->qscale;
+            c->scene_change_score+= s->qscale * s->avctx->scenechange_factor;
         }
     }
 
@@ -1843,7 +1843,7 @@
 /*            if (vard <= 64<<8 || vard < varc) {
                 c->scene_change_score+= ff_sqrt(vard) - ff_sqrt(varc);
             }else{
-                c->scene_change_score+= s->qscale;
+                c->scene_change_score+= s->qscale * s->avctx->scenechange_factor;
             }*/
             return;
         }

Index: utils.c
===================================================================
RCS file: /cvsroot/ffmpeg/ffmpeg/libavcodec/utils.c,v
retrieving revision 1.171
retrieving revision 1.172
diff -u -d -r1.171 -r1.172
--- utils.c	12 Jan 2006 22:43:17 -0000	1.171
+++ utils.c	22 Jan 2006 20:54:52 -0000	1.172
@@ -734,6 +734,7 @@
 {"partp4x4", NULL, 0, FF_OPT_TYPE_CONST, X264_PART_P4X4, INT_MIN, INT_MAX, V|E, "partitions"},
 {"partp8x8", NULL, 0, FF_OPT_TYPE_CONST, X264_PART_P8X8, INT_MIN, INT_MAX, V|E, "partitions"},
 {"partb8x8", NULL, 0, FF_OPT_TYPE_CONST, X264_PART_B8X8, INT_MIN, INT_MAX, V|E, "partitions"},
+{"sc_factor", NULL, OFFSET(scenechange_factor), FF_OPT_TYPE_INT, 6, 0, INT_MAX, V|E},
 {NULL},
 };
 





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