area averageing scaling support (-sws 5) (is identical to bilinear for upscale)

Originally committed as revision 4403 to svn://svn.mplayerhq.hu/mplayer/trunk/postproc

diff --git a/postproc/swscale.c b/postproc/swscale.c
index dc52b2677e5384783ca69d04fb4d6422aeb05059..7acdfbd07416364e4f473896183908e30a4b0a04 100644 (file)
--- a/postproc/swscale.c
+++ b/postproc/swscale.c
@@ -604,6 +604,7 @@ void SwScale_YV12slice(unsigned char* src[], int srcStride[], int srcSliceY ,
                case 2: flags|= SWS_BICUBIC; break;
                case 3: flags|= SWS_X; break;
                case 4: flags|= SWS_POINT; break;
+               case 5: flags|= SWS_AREA; break;
                default:flags|= SWS_BILINEAR; break;
        }
 
@@ -666,7 +667,7 @@ static inline void initFilter(int16_t **outFilter, int16_t **filterPos, int *out
                int xDstInSrc;
                if     (flags&SWS_BICUBIC) filterSize= 4;
                else if(flags&SWS_X      ) filterSize= 4;
-               else                       filterSize= 2;
+               else                       filterSize= 2; // SWS_BILINEAR / SWS_AREA 
 //             printf("%d %d %d\n", filterSize, srcW, dstW);
                filter= (double*)memalign(8, dstW*sizeof(double)*filterSize);
 
@@ -705,6 +706,7 @@ static inline void initFilter(int16_t **outFilter, int16_t **filterPos, int *out
                        }
                        else
                        {
+                               //Bilinear upscale / linear interpolate / Area averaging
                                for(j=0; j<filterSize; j++)
                                {
                                        double d= ABS((xx<<16) - xDstInSrc)/(double)(1<<16);
@@ -721,9 +723,10 @@ static inline void initFilter(int16_t **outFilter, int16_t **filterPos, int *out
        else // downscale
        {
                int xDstInSrc;
-               if(flags&SWS_BICUBIC) filterSize= (int)ceil(1 + 4.0*srcW / (double)dstW);
-               else if(flags&SWS_X)  filterSize= (int)ceil(1 + 4.0*srcW / (double)dstW);
-               else                  filterSize= (int)ceil(1 + 2.0*srcW / (double)dstW);
+               if(flags&SWS_BICUBIC)   filterSize= (int)ceil(1 + 4.0*srcW / (double)dstW);
+               else if(flags&SWS_X)    filterSize= (int)ceil(1 + 4.0*srcW / (double)dstW);
+               else if(flags&SWS_AREA) filterSize= (int)ceil(1 + 1.0*srcW / (double)dstW);
+               else /* BILINEAR */     filterSize= (int)ceil(1 + 2.0*srcW / (double)dstW);
 //             printf("%d %d %d\n", *filterSize, srcW, dstW);
                filter= (double*)memalign(8, dstW*sizeof(double)*filterSize);
 
@@ -749,15 +752,19 @@ static inline void initFilter(int16_t **outFilter, int16_t **filterPos, int *out
                                        else
                                                coeff=0.0;
                                }
-/*                             else if(flags & SWS_X)
+                               else if(flags & SWS_AREA)
                                {
-                               }*/
+                                       double srcPixelSize= (1<<16)/(double)xInc;
+                                       if(d + srcPixelSize/2 < 0.5) coeff= 1.0;
+                                       else if(d - srcPixelSize/2 < 0.5) coeff= (0.5-d)/srcPixelSize + 0.5;
+                                       else coeff=0.0;
+                               }
                                else
                                {
                                        coeff= 1.0 - d;
                                        if(coeff<0) coeff=0;
                                }
-//                             printf("%1.3f %d %d \n", coeff, (int)d, xDstInSrc);
+//                             printf("%1.3f %2.3f %d \n", coeff, d, xDstInSrc);
                                filter[i*filterSize + j]= coeff;
                                xx++;
                        }
@@ -1225,7 +1232,9 @@ SwsContext *getSwsContext(int srcW, int srcH, int srcFormat, int dstW, int dstH,
                else if(flags&SWS_BICUBIC)
                        fprintf(stderr, "\nSwScaler: BICUBIC scaler ");
                else if(flags&SWS_POINT)
-                       fprintf(stderr, "\nSwScaler: POINT scaler ");
+                       fprintf(stderr, "\nSwScaler: Nearest Neighbor / POINT scaler ");
+               else if(flags&SWS_AREA)
+                       fprintf(stderr, "\nSwScaler: Area Averageing scaler ");
                else
                        fprintf(stderr, "\nSwScaler: ehh flags invalid?! ");
 

diff --git a/postproc/swscale.h b/postproc/swscale.h
index c00260fe670834bef74366e370cc6f9e52cd11ef..6ddd5ae44a24b449c8a937edb26d9fc94683000c 100644 (file)
--- a/postproc/swscale.h
+++ b/postproc/swscale.h
@@ -22,6 +22,7 @@
 #define SWS_BICUBIC  4
 #define SWS_X        8
 #define SWS_POINT    0x10
+#define SWS_AREA     0x20
 #define SWS_FULL_UV_IPOL 0x100
 #define SWS_PRINT_INFO 0x1000