ffmpeg | branch: master | Michael Niedermayer <mich...@niedermayer.cc> | Sun Oct 1 18:10:35 2017 +0200| [cd2f69cdd63d3ca5c2388d9ce6737b3e46bb19b2] | committer: Michael Niedermayer
avcodec/dvbsubdec: Factor a few expressions out of compute_default_clut() 32% faster loop Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=cd2f69cdd63d3ca5c2388d9ce6737b3e46bb19b2 --- libavcodec/dvbsubdec.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/libavcodec/dvbsubdec.c b/libavcodec/dvbsubdec.c index b683109643..ef581a9a3f 100644 --- a/libavcodec/dvbsubdec.c +++ b/libavcodec/dvbsubdec.c @@ -653,8 +653,8 @@ static void compute_default_clut(AVSubtitleRect *rect, int w, int h) uint8_t list_inv[256]; int counttab[256] = {0}; int count, i, x, y; - -#define V(x,y) rect->data[0][(x) + (y)*rect->linesize[0]] + ptrdiff_t stride = rect->linesize[0]; +#define V(x,y) rect->data[0][(x) + (y)*stride] for (y = 0; y<h; y++) { for (x = 0; x<w; x++) { int v = V(x,y) + 1; @@ -665,7 +665,7 @@ static void compute_default_clut(AVSubtitleRect *rect, int w, int h) counttab[v-1] += !!((v!=vl) + (v!=vr) + (v!=vt) + (v!=vb)); } } -#define L(x,y) list[ rect->data[0][(x) + (y)*rect->linesize[0]] ] +#define L(x,y) list[d[(x) + (y)*stride]] for (i = 0; i<256; i++) { int scoretab[256] = {0}; @@ -673,12 +673,13 @@ static void compute_default_clut(AVSubtitleRect *rect, int w, int h) int bestv = 0; for (y = 0; y<h; y++) { for (x = 0; x<w; x++) { - int v = rect->data[0][x + y*rect->linesize[0]]; + uint8_t *d = &rect->data[0][x + y*stride]; + int v = *d; int l_m = list[v]; - int l_l = x ? L(x-1, y) : 1; - int l_r = x+1<w ? L(x+1, y) : 1; - int l_t = y ? L(x, y-1) : 1; - int l_b = y+1<h ? L(x, y+1) : 1; + int l_l = x ? L(-1, 0) : 1; + int l_r = x+1<w ? L( 1, 0) : 1; + int l_t = y ? L( 0,-1) : 1; + int l_b = y+1<h ? L( 0, 1) : 1; int score; if (l_m) continue; _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
