avfilter/vf_cropdetect: Unroll 1byte per sample loop

12807 -> 6336 decicycles Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
2014-12-30 02:31:10 +01:00
parent 17dc83ab5e
commit 60e2c3110a
1 changed files with 6 additions and 0 deletions
--- a/libavfilter/vf_cropdetect.c
+++ b/libavfilter/vf_cropdetect.c
@@ -68,6 +68,12 @@ static int checkline(void *ctx, const unsigned char *src, int stride, int len, i

    switch (bpp) {
    case 1:
+        while (len >= 8) {
+            total += src[       0] + src[  stride] + src[2*stride] + src[3*stride]
+                  +  src[4*stride] + src[5*stride] + src[6*stride] + src[7*stride];
+            src += 8*stride;
+            len -= 8;
+        }
        while (--len >= 0) {
            total += src[0];
            src += stride;