[FFmpeg-devel] [PATCH 08/10] avfilter/vf_colorkey: avoid unnecessary floating point multiply

[Ganesh Ajjanagadde]

Normalization can be pulled outside the sqrt.

Signed-off-by: Ganesh Ajjanagadde <gajjanagadde at gmail.com>
---
 libavfilter/vf_colorkey.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavfilter/vf_colorkey.c b/libavfilter/vf_colorkey.c
index 2f670d9..4daf2f5 100644
--- a/libavfilter/vf_colorkey.c
+++ b/libavfilter/vf_colorkey.c
@@ -42,7 +42,7 @@ static uint8_t do_colorkey_pixel(ColorkeyContext *ctx, uint8_t r, uint8_t g, uin
     int dg = (int)g - ctx->colorkey_rgba[1];
     int db = (int)b - ctx->colorkey_rgba[2];
 
-    double diff = sqrt((dr * dr + dg * dg + db * db) / (255.0 * 255.0));
+    double diff = sqrt(dr * dr + dg * dg + db * db) / 255.0;
 
     if (ctx->blend > 0.0001) {
         return av_clipd((diff - ctx->similarity) / ctx->blend, 0.0, 1.0) * 255.0;
-- 
2.6.2