h263 loop filter

fixed h263 modified quantization
CODEC_FLAG_OBMC

Originally committed as revision 2549 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 72 insertions, 0 deletions

diff --git a/libavcodec/dsputil.c b/libavcodec/dsputil.c
index 35bc1a33cb..3deb9ebdba 100644
--- a/libavcodec/dsputil.c
+++ b/libavcodec/dsputil.c
@@ -2261,6 +2261,75 @@ static void put_mspel8_mc22_c(uint8_t *dst, uint8_t *src, int stride){
     wmv2_mspel8_v_lowpass(dst, halfH+8, stride, 8, 8);
 }
 
+static void h263_v_loop_filter_c(uint8_t *src, int stride, int qscale){
+    int x;
+    const int strength= ff_h263_loop_filter_strength[qscale];
+    
+    for(x=0; x<8; x++){
+        int d1, d2, ad1;
+        int p0= src[x-2*stride];
+        int p1= src[x-1*stride];
+        int p2= src[x+0*stride];
+        int p3= src[x+1*stride];
+        int d = (p0 - p3 + 4*(p2 - p1)) / 8;
+
+        if     (d<-2*strength) d1= 0;
+        else if(d<-  strength) d1=-2*strength - d;
+        else if(d<   strength) d1= d;
+        else if(d< 2*strength) d1= 2*strength - d;
+        else                   d1= 0;
+        
+        p1 += d1;
+        p2 -= d1;
+        if(p1&256) p1= ~(p1>>31);
+        if(p2&256) p2= ~(p2>>31);
+        
+        src[x-1*stride] = p1;
+        src[x+0*stride] = p2;
+
+        ad1= ABS(d1);
+        
+        d2= clip((p0-p3)/4, -ad1, ad1);
+        
+        src[x-2*stride] = p0 - d2;
+        src[x+  stride] = p3 + d2;
+    }
+}
+
+static void h263_h_loop_filter_c(uint8_t *src, int stride, int qscale){
+    int y;
+    const int strength= ff_h263_loop_filter_strength[qscale];
+    
+    for(y=0; y<8; y++){
+        int d1, d2, ad1;
+        int p0= src[y*stride-2];
+        int p1= src[y*stride-1];
+        int p2= src[y*stride+0];
+        int p3= src[y*stride+1];
+        int d = (p0 - p3 + 4*(p2 - p1)) / 8;
+
+        if     (d<-2*strength) d1= 0;
+        else if(d<-  strength) d1=-2*strength - d;
+        else if(d<   strength) d1= d;
+        else if(d< 2*strength) d1= 2*strength - d;
+        else                   d1= 0;
+        
+        p1 += d1;
+        p2 -= d1;
+        if(p1&256) p1= ~(p1>>31);
+        if(p2&256) p2= ~(p2>>31);
+        
+        src[y*stride-1] = p1;
+        src[y*stride+0] = p2;
+
+        ad1= ABS(d1)>>1;
+        
+        d2= clip((p0-p3)/4, -ad1, ad1);
+        
+        src[y*stride-2] = p0 - d2;
+        src[y*stride+1] = p3 + d2;
+    }
+}
 
 static inline int pix_abs16x16_c(uint8_t *pix1, uint8_t *pix2, int line_size)
 {
@@ -3048,6 +3117,9 @@ void dsputil_init(DSPContext* c, AVCodecContext *avctx)
     c->diff_bytes= diff_bytes_c;
     c->sub_hfyu_median_prediction= sub_hfyu_median_prediction_c;
     c->bswap_buf= bswap_buf;
+    
+    c->h263_h_loop_filter= h263_h_loop_filter_c;
+    c->h263_v_loop_filter= h263_v_loop_filter_c;
 
 #ifdef HAVE_MMX
     dsputil_init_mmx(c, avctx);