gecko/media/libvpx/vp8/encoder/tokenize.c
Timothy B. Terriberry 276a65b63d Bug 730907 - Update libvpx to v1.0.0, r=cpearce,khuey
--HG--
rename : media/libvpx/vp8/decoder/arm/armv6/dequant_idct_v6.asm => media/libvpx/vp8/common/arm/armv6/dequant_idct_v6.asm
rename : media/libvpx/vp8/decoder/arm/armv6/dequantize_v6.asm => media/libvpx/vp8/common/arm/armv6/dequantize_v6.asm
rename : media/libvpx/vp8/decoder/arm/armv6/idct_blk_v6.c => media/libvpx/vp8/common/arm/armv6/idct_blk_v6.c
rename : media/libvpx/vp8/encoder/arm/armv6/vp8_mse16x16_armv6.asm => media/libvpx/vp8/common/arm/armv6/vp8_mse16x16_armv6.asm
rename : media/libvpx/vp8/encoder/arm/armv6/vp8_sad16x16_armv6.asm => media/libvpx/vp8/common/arm/armv6/vp8_sad16x16_armv6.asm
rename : media/libvpx/vp8/encoder/arm/armv6/vp8_variance16x16_armv6.asm => media/libvpx/vp8/common/arm/armv6/vp8_variance16x16_armv6.asm
rename : media/libvpx/vp8/encoder/arm/armv6/vp8_variance8x8_armv6.asm => media/libvpx/vp8/common/arm/armv6/vp8_variance8x8_armv6.asm
rename : media/libvpx/vp8/encoder/arm/armv6/vp8_variance_halfpixvar16x16_h_armv6.asm => media/libvpx/vp8/common/arm/armv6/vp8_variance_halfpixvar16x16_h_armv6.asm
rename : media/libvpx/vp8/encoder/arm/armv6/vp8_variance_halfpixvar16x16_hv_armv6.asm => media/libvpx/vp8/common/arm/armv6/vp8_variance_halfpixvar16x16_hv_armv6.asm
rename : media/libvpx/vp8/encoder/arm/armv6/vp8_variance_halfpixvar16x16_v_armv6.asm => media/libvpx/vp8/common/arm/armv6/vp8_variance_halfpixvar16x16_v_armv6.asm
rename : media/libvpx/vp8/decoder/arm/dequantize_arm.c => media/libvpx/vp8/common/arm/dequantize_arm.c
rename : media/libvpx/vp8/decoder/arm/dequantize_arm.h => media/libvpx/vp8/common/arm/dequantize_arm.h
rename : media/libvpx/vp8/decoder/arm/neon/dequant_idct_neon.asm => media/libvpx/vp8/common/arm/neon/dequant_idct_neon.asm
rename : media/libvpx/vp8/decoder/arm/neon/dequantizeb_neon.asm => media/libvpx/vp8/common/arm/neon/dequantizeb_neon.asm
rename : media/libvpx/vp8/decoder/arm/neon/idct_blk_neon.c => media/libvpx/vp8/common/arm/neon/idct_blk_neon.c
rename : media/libvpx/vp8/decoder/arm/neon/idct_dequant_0_2x_neon.asm => media/libvpx/vp8/common/arm/neon/idct_dequant_0_2x_neon.asm
rename : media/libvpx/vp8/decoder/arm/neon/idct_dequant_full_2x_neon.asm => media/libvpx/vp8/common/arm/neon/idct_dequant_full_2x_neon.asm
rename : media/libvpx/vp8/encoder/arm/neon/sad16_neon.asm => media/libvpx/vp8/common/arm/neon/sad16_neon.asm
rename : media/libvpx/vp8/encoder/arm/neon/sad8_neon.asm => media/libvpx/vp8/common/arm/neon/sad8_neon.asm
rename : media/libvpx/vp8/encoder/arm/neon/variance_neon.asm => media/libvpx/vp8/common/arm/neon/variance_neon.asm
rename : media/libvpx/vp8/encoder/arm/neon/vp8_mse16x16_neon.asm => media/libvpx/vp8/common/arm/neon/vp8_mse16x16_neon.asm
rename : media/libvpx/vp8/encoder/arm/neon/vp8_subpixelvariance16x16_neon.asm => media/libvpx/vp8/common/arm/neon/vp8_subpixelvariance16x16_neon.asm
rename : media/libvpx/vp8/encoder/arm/neon/vp8_subpixelvariance16x16s_neon.asm => media/libvpx/vp8/common/arm/neon/vp8_subpixelvariance16x16s_neon.asm
rename : media/libvpx/vp8/encoder/arm/neon/vp8_subpixelvariance8x8_neon.asm => media/libvpx/vp8/common/arm/neon/vp8_subpixelvariance8x8_neon.asm
rename : media/libvpx/vp8/encoder/arm/variance_arm.c => media/libvpx/vp8/common/arm/variance_arm.c
rename : media/libvpx/vp8/encoder/arm/variance_arm.h => media/libvpx/vp8/common/arm/variance_arm.h
rename : media/libvpx/vp8/decoder/dequantize.c => media/libvpx/vp8/common/dequantize.c
rename : media/libvpx/vp8/decoder/dequantize.h => media/libvpx/vp8/common/dequantize.h
rename : media/libvpx/vp8/decoder/idct_blk.c => media/libvpx/vp8/common/idct_blk.c
rename : media/libvpx/vp8/encoder/sad_c.c => media/libvpx/vp8/common/sad_c.c
rename : media/libvpx/vp8/encoder/variance.h => media/libvpx/vp8/common/variance.h
rename : media/libvpx/vp8/encoder/variance_c.c => media/libvpx/vp8/common/variance_c.c
rename : media/libvpx/vp8/decoder/x86/dequantize_mmx.asm => media/libvpx/vp8/common/x86/dequantize_mmx.asm
rename : media/libvpx/vp8/decoder/x86/dequantize_x86.h => media/libvpx/vp8/common/x86/dequantize_x86.h
rename : media/libvpx/vp8/decoder/x86/idct_blk_mmx.c => media/libvpx/vp8/common/x86/idct_blk_mmx.c
rename : media/libvpx/vp8/decoder/x86/idct_blk_sse2.c => media/libvpx/vp8/common/x86/idct_blk_sse2.c
rename : media/libvpx/vp8/encoder/x86/sad_mmx.asm => media/libvpx/vp8/common/x86/sad_mmx.asm
rename : media/libvpx/vp8/encoder/x86/sad_sse2.asm => media/libvpx/vp8/common/x86/sad_sse2.asm
rename : media/libvpx/vp8/encoder/x86/sad_sse3.asm => media/libvpx/vp8/common/x86/sad_sse3.asm
rename : media/libvpx/vp8/encoder/x86/sad_sse4.asm => media/libvpx/vp8/common/x86/sad_sse4.asm
rename : media/libvpx/vp8/encoder/x86/sad_ssse3.asm => media/libvpx/vp8/common/x86/sad_ssse3.asm
rename : media/libvpx/vp8/encoder/x86/variance_impl_mmx.asm => media/libvpx/vp8/common/x86/variance_impl_mmx.asm
rename : media/libvpx/vp8/encoder/x86/variance_impl_sse2.asm => media/libvpx/vp8/common/x86/variance_impl_sse2.asm
rename : media/libvpx/vp8/encoder/x86/variance_impl_ssse3.asm => media/libvpx/vp8/common/x86/variance_impl_ssse3.asm
rename : media/libvpx/vp8/encoder/x86/variance_mmx.c => media/libvpx/vp8/common/x86/variance_mmx.c
rename : media/libvpx/vp8/encoder/x86/variance_sse2.c => media/libvpx/vp8/common/x86/variance_sse2.c
rename : media/libvpx/vp8/encoder/x86/variance_ssse3.c => media/libvpx/vp8/common/x86/variance_ssse3.c
rename : media/libvpx/vp8/encoder/x86/variance_x86.h => media/libvpx/vp8/common/x86/variance_x86.h
rename : media/libvpx/vp8/encoder/arm/armv6/vp8_fast_fdct4x4_armv6.asm => media/libvpx/vp8/encoder/arm/armv6/vp8_short_fdct4x4_armv6.asm
rename : media/libvpx/vp8/common/defaultcoefcounts.c => media/libvpx/vp8/encoder/defaultcoefcounts.h
2012-04-29 20:51:44 -07:00

601 lines
15 KiB
C

/*
* 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 <math.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "onyx_int.h"
#include "tokenize.h"
#include "vpx_mem/vpx_mem.h"
/* Global event counters used for accumulating statistics across several
compressions, then generating context.c = initial stats. */
#ifdef ENTROPY_STATS
_int64 context_counters[BLOCK_TYPES] [COEF_BANDS] [PREV_COEF_CONTEXTS] [MAX_ENTROPY_TOKENS];
#endif
void vp8_stuff_mb(VP8_COMP *cpi, MACROBLOCKD *x, TOKENEXTRA **t) ;
void vp8_fix_contexts(MACROBLOCKD *x);
static TOKENVALUE dct_value_tokens[DCT_MAX_VALUE*2];
const TOKENVALUE *vp8_dct_value_tokens_ptr;
static int dct_value_cost[DCT_MAX_VALUE*2];
const int *vp8_dct_value_cost_ptr;
#if 0
int skip_true_count = 0;
int skip_false_count = 0;
#endif
static void fill_value_tokens()
{
TOKENVALUE *const t = dct_value_tokens + DCT_MAX_VALUE;
vp8_extra_bit_struct *const e = vp8_extra_bits;
int i = -DCT_MAX_VALUE;
int sign = 1;
do
{
if (!i)
sign = 0;
{
const int a = sign ? -i : i;
int eb = sign;
if (a > 4)
{
int j = 4;
while (++j < 11 && e[j].base_val <= a) {}
t[i].Token = --j;
eb |= (a - e[j].base_val) << 1;
}
else
t[i].Token = a;
t[i].Extra = eb;
}
// initialize the cost for extra bits for all possible coefficient value.
{
int cost = 0;
vp8_extra_bit_struct *p = vp8_extra_bits + t[i].Token;
if (p->base_val)
{
const int extra = t[i].Extra;
const int Length = p->Len;
if (Length)
cost += vp8_treed_cost(p->tree, p->prob, extra >> 1, Length);
cost += vp8_cost_bit(vp8_prob_half, extra & 1); /* sign */
dct_value_cost[i + DCT_MAX_VALUE] = cost;
}
}
}
while (++i < DCT_MAX_VALUE);
vp8_dct_value_tokens_ptr = dct_value_tokens + DCT_MAX_VALUE;
vp8_dct_value_cost_ptr = dct_value_cost + DCT_MAX_VALUE;
}
static void tokenize2nd_order_b
(
MACROBLOCKD *x,
TOKENEXTRA **tp,
VP8_COMP *cpi
)
{
int pt; /* near block/prev token context index */
int c; /* start at DC */
TOKENEXTRA *t = *tp;/* store tokens starting here */
const BLOCKD *b;
const short *qcoeff_ptr;
ENTROPY_CONTEXT * a;
ENTROPY_CONTEXT * l;
int band, rc, v, token;
int eob;
b = x->block + 24;
qcoeff_ptr = b->qcoeff;
a = (ENTROPY_CONTEXT *)x->above_context + 8;
l = (ENTROPY_CONTEXT *)x->left_context + 8;
eob = x->eobs[24];
VP8_COMBINEENTROPYCONTEXTS(pt, *a, *l);
if(!eob)
{
/* c = band for this case */
t->Token = DCT_EOB_TOKEN;
t->context_tree = cpi->common.fc.coef_probs [1] [0] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [1] [0] [pt] [DCT_EOB_TOKEN];
t++;
*tp = t;
*a = *l = 0;
return;
}
v = qcoeff_ptr[0];
t->Extra = vp8_dct_value_tokens_ptr[v].Extra;
token = vp8_dct_value_tokens_ptr[v].Token;
t->Token = token;
t->context_tree = cpi->common.fc.coef_probs [1] [0] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [1] [0] [pt] [token];
pt = vp8_prev_token_class[token];
t++;
c = 1;
for (; c < eob; c++)
{
rc = vp8_default_zig_zag1d[c];
band = vp8_coef_bands[c];
v = qcoeff_ptr[rc];
t->Extra = vp8_dct_value_tokens_ptr[v].Extra;
token = vp8_dct_value_tokens_ptr[v].Token;
t->Token = token;
t->context_tree = cpi->common.fc.coef_probs [1] [band] [pt];
t->skip_eob_node = ((pt == 0));
++cpi->coef_counts [1] [band] [pt] [token];
pt = vp8_prev_token_class[token];
t++;
}
if (c < 16)
{
band = vp8_coef_bands[c];
t->Token = DCT_EOB_TOKEN;
t->context_tree = cpi->common.fc.coef_probs [1] [band] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [1] [band] [pt] [DCT_EOB_TOKEN];
t++;
}
*tp = t;
*a = *l = 1;
}
static void tokenize1st_order_b
(
MACROBLOCKD *x,
TOKENEXTRA **tp,
int type, /* which plane: 0=Y no DC, 1=Y2, 2=UV, 3=Y with DC */
VP8_COMP *cpi
)
{
unsigned int block;
const BLOCKD *b;
int pt; /* near block/prev token context index */
int c;
int token;
TOKENEXTRA *t = *tp;/* store tokens starting here */
const short *qcoeff_ptr;
ENTROPY_CONTEXT * a;
ENTROPY_CONTEXT * l;
int band, rc, v;
int tmp1, tmp2;
b = x->block;
/* Luma */
for (block = 0; block < 16; block++, b++)
{
tmp1 = vp8_block2above[block];
tmp2 = vp8_block2left[block];
qcoeff_ptr = b->qcoeff;
a = (ENTROPY_CONTEXT *)x->above_context + tmp1;
l = (ENTROPY_CONTEXT *)x->left_context + tmp2;
VP8_COMBINEENTROPYCONTEXTS(pt, *a, *l);
c = type ? 0 : 1;
if(c >= *b->eob)
{
/* c = band for this case */
t->Token = DCT_EOB_TOKEN;
t->context_tree = cpi->common.fc.coef_probs [type] [c] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [type] [c] [pt] [DCT_EOB_TOKEN];
t++;
*tp = t;
*a = *l = 0;
continue;
}
v = qcoeff_ptr[c];
t->Extra = vp8_dct_value_tokens_ptr[v].Extra;
token = vp8_dct_value_tokens_ptr[v].Token;
t->Token = token;
t->context_tree = cpi->common.fc.coef_probs [type] [c] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [type] [c] [pt] [token];
pt = vp8_prev_token_class[token];
t++;
c++;
for (; c < *b->eob; c++)
{
rc = vp8_default_zig_zag1d[c];
band = vp8_coef_bands[c];
v = qcoeff_ptr[rc];
t->Extra = vp8_dct_value_tokens_ptr[v].Extra;
token = vp8_dct_value_tokens_ptr[v].Token;
t->Token = token;
t->context_tree = cpi->common.fc.coef_probs [type] [band] [pt];
t->skip_eob_node = (pt == 0);
++cpi->coef_counts [type] [band] [pt] [token];
pt = vp8_prev_token_class[token];
t++;
}
if (c < 16)
{
band = vp8_coef_bands[c];
t->Token = DCT_EOB_TOKEN;
t->context_tree = cpi->common.fc.coef_probs [type] [band] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [type] [band] [pt] [DCT_EOB_TOKEN];
t++;
}
*tp = t;
*a = *l = 1;
}
/* Chroma */
for (block = 16; block < 24; block++, b++)
{
tmp1 = vp8_block2above[block];
tmp2 = vp8_block2left[block];
qcoeff_ptr = b->qcoeff;
a = (ENTROPY_CONTEXT *)x->above_context + tmp1;
l = (ENTROPY_CONTEXT *)x->left_context + tmp2;
VP8_COMBINEENTROPYCONTEXTS(pt, *a, *l);
if(!(*b->eob))
{
/* c = band for this case */
t->Token = DCT_EOB_TOKEN;
t->context_tree = cpi->common.fc.coef_probs [2] [0] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [2] [0] [pt] [DCT_EOB_TOKEN];
t++;
*tp = t;
*a = *l = 0;
continue;
}
v = qcoeff_ptr[0];
t->Extra = vp8_dct_value_tokens_ptr[v].Extra;
token = vp8_dct_value_tokens_ptr[v].Token;
t->Token = token;
t->context_tree = cpi->common.fc.coef_probs [2] [0] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [2] [0] [pt] [token];
pt = vp8_prev_token_class[token];
t++;
c = 1;
for (; c < *b->eob; c++)
{
rc = vp8_default_zig_zag1d[c];
band = vp8_coef_bands[c];
v = qcoeff_ptr[rc];
t->Extra = vp8_dct_value_tokens_ptr[v].Extra;
token = vp8_dct_value_tokens_ptr[v].Token;
t->Token = token;
t->context_tree = cpi->common.fc.coef_probs [2] [band] [pt];
t->skip_eob_node = (pt == 0);
++cpi->coef_counts [2] [band] [pt] [token];
pt = vp8_prev_token_class[token];
t++;
}
if (c < 16)
{
band = vp8_coef_bands[c];
t->Token = DCT_EOB_TOKEN;
t->context_tree = cpi->common.fc.coef_probs [2] [band] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [2] [band] [pt] [DCT_EOB_TOKEN];
t++;
}
*tp = t;
*a = *l = 1;
}
}
static int mb_is_skippable(MACROBLOCKD *x, int has_y2_block)
{
int skip = 1;
int i = 0;
if (has_y2_block)
{
for (i = 0; i < 16; i++)
skip &= (x->eobs[i] < 2);
}
for (; i < 24 + has_y2_block; i++)
skip &= (!x->eobs[i]);
return skip;
}
void vp8_tokenize_mb(VP8_COMP *cpi, MACROBLOCKD *x, TOKENEXTRA **t)
{
int plane_type;
int has_y2_block;
has_y2_block = (x->mode_info_context->mbmi.mode != B_PRED
&& x->mode_info_context->mbmi.mode != SPLITMV);
x->mode_info_context->mbmi.mb_skip_coeff = mb_is_skippable(x, has_y2_block);
if (x->mode_info_context->mbmi.mb_skip_coeff)
{
cpi->skip_true_count++;
if (!cpi->common.mb_no_coeff_skip)
vp8_stuff_mb(cpi, x, t) ;
else
{
vp8_fix_contexts(x);
}
return;
}
cpi->skip_false_count++;
plane_type = 3;
if(has_y2_block)
{
tokenize2nd_order_b(x, t, cpi);
plane_type = 0;
}
tokenize1st_order_b(x, t, plane_type, cpi);
}
#ifdef ENTROPY_STATS
void init_context_counters(void)
{
vpx_memset(context_counters, 0, sizeof(context_counters));
}
void print_context_counters()
{
int type, band, pt, t;
FILE *const f = fopen("context.c", "w");
fprintf(f, "#include \"entropy.h\"\n");
fprintf(f, "\n/* *** GENERATED FILE: DO NOT EDIT *** */\n\n");
fprintf(f, "int Contexts[BLOCK_TYPES] [COEF_BANDS] [PREV_COEF_CONTEXTS] [MAX_ENTROPY_TOKENS];\n\n");
fprintf(f, "const int default_contexts[BLOCK_TYPES] [COEF_BANDS] [PREV_COEF_CONTEXTS] [MAX_ENTROPY_TOKENS] = {");
# define Comma( X) (X? ",":"")
type = 0;
do
{
fprintf(f, "%s\n { /* block Type %d */", Comma(type), type);
band = 0;
do
{
fprintf(f, "%s\n { /* Coeff Band %d */", Comma(band), band);
pt = 0;
do
{
fprintf(f, "%s\n {", Comma(pt));
t = 0;
do
{
const _int64 x = context_counters [type] [band] [pt] [t];
const int y = (int) x;
assert(x == (_int64) y); /* no overflow handling yet */
fprintf(f, "%s %d", Comma(t), y);
}
while (++t < MAX_ENTROPY_TOKENS);
fprintf(f, "}");
}
while (++pt < PREV_COEF_CONTEXTS);
fprintf(f, "\n }");
}
while (++band < COEF_BANDS);
fprintf(f, "\n }");
}
while (++type < BLOCK_TYPES);
fprintf(f, "\n};\n");
fclose(f);
}
#endif
void vp8_tokenize_initialize()
{
fill_value_tokens();
}
static void stuff2nd_order_b
(
TOKENEXTRA **tp,
ENTROPY_CONTEXT *a,
ENTROPY_CONTEXT *l,
VP8_COMP *cpi
)
{
int pt; /* near block/prev token context index */
TOKENEXTRA *t = *tp; /* store tokens starting here */
VP8_COMBINEENTROPYCONTEXTS(pt, *a, *l);
t->Token = DCT_EOB_TOKEN;
t->context_tree = cpi->common.fc.coef_probs [1] [0] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [1] [0] [pt] [DCT_EOB_TOKEN];
++t;
*tp = t;
pt = 0;
*a = *l = pt;
}
static void stuff1st_order_b
(
TOKENEXTRA **tp,
ENTROPY_CONTEXT *a,
ENTROPY_CONTEXT *l,
int type,
VP8_COMP *cpi
)
{
int pt; /* near block/prev token context index */
int band;
TOKENEXTRA *t = *tp; /* store tokens starting here */
VP8_COMBINEENTROPYCONTEXTS(pt, *a, *l);
band = type ? 0 : 1;
t->Token = DCT_EOB_TOKEN;
t->context_tree = cpi->common.fc.coef_probs [type] [band] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts [type] [band] [pt] [DCT_EOB_TOKEN];
++t;
*tp = t;
pt = 0; /* 0 <-> all coeff data is zero */
*a = *l = pt;
}
static
void stuff1st_order_buv
(
TOKENEXTRA **tp,
ENTROPY_CONTEXT *a,
ENTROPY_CONTEXT *l,
VP8_COMP *cpi
)
{
int pt; /* near block/prev token context index */
TOKENEXTRA *t = *tp; /* store tokens starting here */
VP8_COMBINEENTROPYCONTEXTS(pt, *a, *l);
t->Token = DCT_EOB_TOKEN;
t->context_tree = cpi->common.fc.coef_probs [2] [0] [pt];
t->skip_eob_node = 0;
++cpi->coef_counts[2] [0] [pt] [DCT_EOB_TOKEN];
++t;
*tp = t;
pt = 0; /* 0 <-> all coeff data is zero */
*a = *l = pt;
}
void vp8_stuff_mb(VP8_COMP *cpi, MACROBLOCKD *x, TOKENEXTRA **t)
{
ENTROPY_CONTEXT * A = (ENTROPY_CONTEXT *)x->above_context;
ENTROPY_CONTEXT * L = (ENTROPY_CONTEXT *)x->left_context;
int plane_type;
int b;
plane_type = 3;
if((x->mode_info_context->mbmi.mode != B_PRED
&& x->mode_info_context->mbmi.mode != SPLITMV))
{
stuff2nd_order_b(t,
A + vp8_block2above[24], L + vp8_block2left[24], cpi);
plane_type = 0;
}
for (b = 0; b < 16; b++)
stuff1st_order_b(t,
A + vp8_block2above[b],
L + vp8_block2left[b], plane_type, cpi);
for (b = 16; b < 24; b++)
stuff1st_order_buv(t,
A + vp8_block2above[b],
L + vp8_block2left[b], cpi);
}
void vp8_fix_contexts(MACROBLOCKD *x)
{
/* Clear entropy contexts for Y2 blocks */
if (x->mode_info_context->mbmi.mode != B_PRED && x->mode_info_context->mbmi.mode != SPLITMV)
{
vpx_memset(x->above_context, 0, sizeof(ENTROPY_CONTEXT_PLANES));
vpx_memset(x->left_context, 0, sizeof(ENTROPY_CONTEXT_PLANES));
}
else
{
vpx_memset(x->above_context, 0, sizeof(ENTROPY_CONTEXT_PLANES)-1);
vpx_memset(x->left_context, 0, sizeof(ENTROPY_CONTEXT_PLANES)-1);
}
}