Adjust the vbp early termination threshold slightly

Calculated cpi->vbp_threshold_sad from this frame's dequant value.
The encoding quality and speed didn't change much. Borg test
result: PSNR: -0.002%, SSIM: -0.003%.

Change-Id: I97c9826986f39582f29910d637d08a69c90afdee

diff --git a/vp9/encoder/vp9_encodeframe.c b/vp9/encoder/vp9_encodeframe.c
index fa7a694c532199290e6ed3e6007887d5c01e7405..cd50ccfd936b3f7f1e4bd5800a7ef5dd32c6ea51 100644 (file)
--- a/vp9/encoder/vp9_encodeframe.c
+++ b/vp9/encoder/vp9_encodeframe.c
@@ -499,7 +499,8 @@ void vp9_set_vbp_thresholds(VP9_COMP *cpi, int q) {
         cpi->vbp_thresholds[0] = threshold_base;
         cpi->vbp_thresholds[1] = (5 * threshold_base) >> 2;
         cpi->vbp_thresholds[2] = threshold_base << cpi->oxcf.speed;
-        cpi->vbp_threshold_sad = 1000;
+        cpi->vbp_threshold_sad = (cpi->y_dequant[q][1] << 1) > 1000 ?
+            (cpi->y_dequant[q][1] << 1) : 1000;
       }
       cpi->vbp_bsize_min = BLOCK_16X16;
     }