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Yaowu Xu authored
The qindex for a segment was not clamped in ABSDATA mode, which may cause invalid memory access if an ill-formed stream has a negative value in ABSDATA mode. This commit added clamp to make sure qindex for a segment always fall into valid range. Change-Id: I0a74d00f4ef40aec7edaeca1d03c8645e23ab08c
e22b12e3
/* * Copyright (c) 2010 The WebM project authors. All Rights Reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */#include "vp9/common/vp9_common.h"#include "vp9/common/vp9_quant_common.h"#include "vp9/common/vp9_seg_common.h"#if 1static const int16_t dc_qlookup[QINDEX_RANGE] = { 4, 8, 8, 9, 10, 11, 12, 12, 13, 14, 15, 16, 17, 18, 19, 19, 20, 21, 22, 23, 24, 25, 26, 26, 27, 28, 29, 30, 31, 32, 32, 33, 34, 35, 36, 37, 38, 38, 39, 40, 41, 42, 43, 43, 44, 45, 46, 47, 48, 48, 49, 50, 51, 52, 53, 53, 54, 55, 56, 57, 57, 58, 59, 60, 61, 62, 62, 63, 64, 65, 66, 66, 67, 68, 69, 70, 70, 71, 72, 73, 74, 74, 75, 76, 77, 78, 78, 79, 80, 81, 81, 82, 83, 84, 85, 85, 87, 88, 90, 92, 93, 95, 96, 98, 99, 101, 102, 104, 105, 107, 108, 110, 111, 113, 114, 116, 117, 118, 120, 121, 123, 125, 127, 129, 131, 134, 136, 138, 140, 142, 144, 146, 148, 150, 152, 154, 156, 158, 161, 164, 166, 169, 172, 174, 177, 180, 182, 185, 187, 190, 192, 195, 199, 202, 205, 208, 211, 214, 217, 220, 223, 226, 230, 233, 237, 240, 243, 247, 250, 253, 257, 261, 265, 269, 272, 276, 280, 284, 288, 292, 296, 300, 304, 309, 313, 317, 322, 326, 330, 335, 340, 344, 349, 354, 359, 364, 369, 374, 379, 384, 389, 395, 400, 406, 411, 417, 423, 429, 435, 441, 447, 454, 461, 467, 475, 482, 489, 497, 505, 513, 522, 530, 539, 549, 559, 569, 579, 590, 602, 614, 626, 640, 654, 668, 684, 700, 717, 736, 755, 775, 796, 819, 843, 869, 896, 925, 955, 988, 1022, 1058, 1098, 1139, 1184, 1232, 1282, 1336,};static const int16_t ac_qlookup[QINDEX_RANGE] = { 4, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 146, 148, 150, 152, 155, 158, 161, 164, 167, 170, 173, 176, 179, 182, 185, 188, 191, 194, 197, 200, 203, 207, 211, 215, 219, 223, 227, 231, 235, 239, 243, 247, 251, 255, 260,7172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140
265, 270, 275, 280, 285, 290, 295, 300,
305, 311, 317, 323, 329, 335, 341, 347,
353, 359, 366, 373, 380, 387, 394, 401,
408, 416, 424, 432, 440, 448, 456, 465,
474, 483, 492, 501, 510, 520, 530, 540,
550, 560, 571, 582, 593, 604, 615, 627,
639, 651, 663, 676, 689, 702, 715, 729,
743, 757, 771, 786, 801, 816, 832, 848,
864, 881, 898, 915, 933, 951, 969, 988,
1007, 1026, 1046, 1066, 1087, 1108, 1129, 1151,
1173, 1196, 1219, 1243, 1267, 1292, 1317, 1343,
1369, 1396, 1423, 1451, 1479, 1508, 1537, 1567,
1597, 1628, 1660, 1692, 1725, 1759, 1793, 1828,
};
void vp9_init_quant_tables(void) { }
#else
static int16_t dc_qlookup[QINDEX_RANGE];
static int16_t ac_qlookup[QINDEX_RANGE];
#define ACDC_MIN 8
// TODO(dkovalev) move to common and reuse
static double poly3(double a, double b, double c, double d, double x) {
return a*x*x*x + b*x*x + c*x + d;
}
void vp9_init_quant_tables() {
int i, val = 4;
// A "real" q of 1.0 forces lossless mode.
// In practice non lossless Q's between 1.0 and 2.0 (represented here by
// integer values from 5-7 give poor rd results (lower psnr and often
// larger size than the lossless encode. To block out those "not very useful"
// values we increment the ac and dc q lookup values by 4 after position 0.
ac_qlookup[0] = val;
dc_qlookup[0] = val;
val += 4;
for (i = 1; i < QINDEX_RANGE; i++) {
const int ac_val = val;
val = (int)(val * 1.01975);
if (val == ac_val)
++val;
ac_qlookup[i] = (int16_t)ac_val;
dc_qlookup[i] = (int16_t)MAX(ACDC_MIN, poly3(0.000000305, -0.00065, 0.9,
0.5, ac_val));
}
}
#endif
int16_t vp9_dc_quant(int qindex, int delta) {
return dc_qlookup[clamp(qindex + delta, 0, MAXQ)];
}
int16_t vp9_ac_quant(int qindex, int delta) {
return ac_qlookup[clamp(qindex + delta, 0, MAXQ)];
}
int vp9_get_qindex(const struct segmentation *seg, int segment_id,
int base_qindex) {
if (vp9_segfeature_active(seg, segment_id, SEG_LVL_ALT_Q)) {
const int data = vp9_get_segdata(seg, segment_id, SEG_LVL_ALT_Q);
const int seg_qindex = seg->abs_delta == SEGMENT_ABSDATA ?
data : base_qindex + data;
return clamp(seg_qindex, 0, MAXQ);
} else {
141142143144145
return base_qindex;
}
}