ref: c3f7bb16b4384680ef67af7c67009c60bf85c6ec
parent: e2b4ef131312f2c649d159d21e2c486bdbac19b4
author: Marco <marpan@google.com>
date: Thu Feb 26 09:27:16 EST 2015
Fix arithmetic overflow warnings. Change-Id: Ib85b5bc135aa0907a76b8c74faafe577e27d014f
--- a/vp9/encoder/vp9_aq_cyclicrefresh.c
+++ b/vp9/encoder/vp9_aq_cyclicrefresh.c
@@ -368,9 +368,11 @@
cr->time_for_refresh = 0;
// Set rate threshold to some multiple (set to 2 for now) of the target
// rate (target is given by sb64_target_rate and scaled by 256).
- cr->thresh_rate_sb = (rc->sb64_target_rate << 8) << 1;
+ cr->thresh_rate_sb = ((int64_t)(rc->sb64_target_rate) << 8) << 1;
// Distortion threshold, quadratic in Q, scale factor to be adjusted.
- cr->thresh_dist_sb = (int)(q * q) << 2;
+ // q will not exceed 457, so (q * q) is within 32bit; see:
+ // vp9_convert_qindex_to_q(), vp9_ac_quant(), ac_qlookup*[].
+ cr->thresh_dist_sb = ((int64_t)(q * q)) << 2;
cr->motion_thresh = 32;
// Set up segmentation.
// Clear down the segment map.
--
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