Module: libav Branch: master Commit: d341d5fd2cd7e301a20dcb50f3e1445571765023
Author: Mans Rullgard <[email protected]> Committer: Mans Rullgard <[email protected]> Date: Sat Oct 8 01:37:20 2011 +0100 dnxhdenc: fixed signed multiplication overflow The low 32 bits of a multiplication are the same for signed and unsigned operands. Casting to unsigned before multiplying is thus equivalent while avoiding signed overflow, which is undefined by the C99 standard. Signed-off-by: Mans Rullgard <[email protected]> --- libavcodec/dnxhdenc.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/libavcodec/dnxhdenc.c b/libavcodec/dnxhdenc.c index db46085..89e5c08 100644 --- a/libavcodec/dnxhdenc.c +++ b/libavcodec/dnxhdenc.c @@ -623,7 +623,7 @@ static int dnxhd_mb_var_thread(AVCodecContext *avctx, void *arg, int jobnr, int for (mb_x = 0; mb_x < ctx->m.mb_width; ++mb_x, pix += 16) { unsigned mb = mb_y * ctx->m.mb_width + mb_x; int sum = ctx->m.dsp.pix_sum(pix, ctx->m.linesize); - int varc = (ctx->m.dsp.pix_norm1(pix, ctx->m.linesize) - (((unsigned)(sum*sum))>>8)+128)>>8; + int varc = (ctx->m.dsp.pix_norm1(pix, ctx->m.linesize) - (((unsigned)sum*sum)>>8)+128)>>8; ctx->mb_cmp[mb].value = varc; ctx->mb_cmp[mb].mb = mb; } _______________________________________________ libav-commits mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-commits
