From 8aaf5ec4c7f3e4a5d6806550d1415c20b337230a Mon Sep 17 00:00:00 2001 From: James Zern Date: Tue, 30 Jun 2015 15:09:48 -0700 Subject: [PATCH] vp9_dsubexp: remove clamp in inv_remap_prob() the max value of the lookup in expanded form is: (((1 << 7) - 1) << 1) - 65 + 1 + 64 = 254 remove the clamp [0, 253] and add one table entry Change-Id: I0b5d0c66702fdb0b8f1cc9ab9b0dac66326e85a6 --- vp9/decoder/vp9_dsubexp.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/vp9/decoder/vp9_dsubexp.c b/vp9/decoder/vp9_dsubexp.c index c22617edb..3df548120 100644 --- a/vp9/decoder/vp9_dsubexp.c +++ b/vp9/decoder/vp9_dsubexp.c @@ -8,6 +8,8 @@ * be found in the AUTHORS file in the root of the source tree. */ +#include + #include "vp9/common/vp9_entropy.h" #include "vp9/decoder/vp9_dsubexp.h" @@ -27,7 +29,7 @@ static int decode_uniform(vp9_reader *r) { } static int inv_remap_prob(int v, int m) { - static int inv_map_table[MAX_PROB - 1] = { + static int inv_map_table[MAX_PROB] = { 6, 19, 32, 45, 58, 71, 84, 97, 110, 123, 136, 149, 162, 175, 188, 201, 214, 227, 240, 253, 0, 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, 21, 22, 23, 24, 25, 26, @@ -44,11 +46,9 @@ static int inv_remap_prob(int v, int m) { 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, - 238, 239, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252 + 238, 239, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 252 }; - // The clamp is not necessary for conforming VP9 stream, it is added to - // prevent out of bound access for bad input data - v = clamp(v, 0, 253); + assert(v < (int)(sizeof(inv_map_table) / sizeof(inv_map_table[0]))); v = inv_map_table[v]; m--; if ((m << 1) <= MAX_PROB) {