/*****************************************************************************
- * rdo.c: h264 encoder library (rate-distortion optimization)
+ * rdo.c: rate-distortion optimization
*****************************************************************************
- * Copyright (C) 2005 x264 project
+ * Copyright (C) 2005-2010 x264 project
*
* Authors: Loren Merritt <lorenm@u.washington.edu>
+ * Fiona Glaser <fiona@x264.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111, USA.
+ *
+ * This program is also available under a commercial proprietary license.
+ * For more information, contact us at licensing@x264.com.
*****************************************************************************/
/* duplicate all the writer functions, just calculating bit cost
* instead of writing the bitstream.
* TODO: use these for fast 1st pass too. */
-#define RDO_SKIP_BS
+#define RDO_SKIP_BS 1
-static int cabac_prefix_transition[15][128];
-static int cabac_prefix_size[15][128];
+/* Transition and size tables for abs<9 MVD and residual coding */
+/* Consist of i_prefix-2 1s, one zero, and a bypass sign bit */
+static uint8_t cabac_transition_unary[15][128];
+static uint16_t cabac_size_unary[15][128];
+/* Transition and size tables for abs>9 MVD */
+/* Consist of 5 1s and a bypass sign bit */
+static uint8_t cabac_transition_5ones[128];
+static uint16_t cabac_size_5ones[128];
/* CAVLC: produces exactly the same bit count as a normal encode */
/* this probably still leaves some unnecessary computations */
#define bs_write_ue(s,v) ((s)->i_bits_encoded += bs_size_ue(v))
#define bs_write_se(s,v) ((s)->i_bits_encoded += bs_size_se(v))
#define bs_write_te(s,v,l) ((s)->i_bits_encoded += bs_size_te(v,l))
-#define x264_macroblock_write_cavlc x264_macroblock_size_cavlc
+#define x264_macroblock_write_cavlc static x264_macroblock_size_cavlc
#include "cavlc.c"
/* CABAC: not exactly the same. x264_cabac_size_decision() keeps track of
* fractional bits, but only finite precision. */
+#undef x264_cabac_encode_decision
+#undef x264_cabac_encode_decision_noup
+#undef x264_cabac_encode_bypass
+#undef x264_cabac_encode_terminal
#define x264_cabac_encode_decision(c,x,v) x264_cabac_size_decision(c,x,v)
-#define x264_cabac_encode_terminal(c) x264_cabac_size_decision(c,276,0)
+#define x264_cabac_encode_decision_noup(c,x,v) x264_cabac_size_decision_noup(c,x,v)
+#define x264_cabac_encode_terminal(c) ((c)->f8_bits_encoded += 7)
#define x264_cabac_encode_bypass(c,v) ((c)->f8_bits_encoded += 256)
-#define x264_cabac_encode_flush(h,c)
-#define x264_macroblock_write_cabac x264_macroblock_size_cabac
+#define x264_cabac_encode_ue_bypass(c,e,v) ((c)->f8_bits_encoded += (bs_size_ue_big(v+(1<<e)-1)-e)<<8)
+#define x264_macroblock_write_cabac static x264_macroblock_size_cabac
#include "cabac.c"
+#define COPY_CABAC h->mc.memcpy_aligned( &cabac_tmp.f8_bits_encoded, &h->cabac.f8_bits_encoded, \
+ sizeof(x264_cabac_t) - offsetof(x264_cabac_t,f8_bits_encoded) )
+#define COPY_CABAC_PART( pos, size )\
+ memcpy( &cb->state[pos], &h->cabac.state[pos], size )
-static int ssd_mb( x264_t *h )
+static ALWAYS_INLINE uint64_t cached_hadamard( x264_t *h, int size, int x, int y )
{
- return h->pixf.ssd[PIXEL_16x16]( h->mb.pic.p_fenc[0], FENC_STRIDE,
- h->mb.pic.p_fdec[0], FDEC_STRIDE )
- + h->pixf.ssd[PIXEL_8x8]( h->mb.pic.p_fenc[1], FENC_STRIDE,
- h->mb.pic.p_fdec[1], FDEC_STRIDE )
- + h->pixf.ssd[PIXEL_8x8]( h->mb.pic.p_fenc[2], FENC_STRIDE,
- h->mb.pic.p_fdec[2], FDEC_STRIDE );
+ static const uint8_t hadamard_shift_x[4] = {4, 4, 3, 3};
+ static const uint8_t hadamard_shift_y[4] = {4-0, 3-0, 4-1, 3-1};
+ static const uint8_t hadamard_offset[4] = {0, 1, 3, 5};
+ int cache_index = (x >> hadamard_shift_x[size]) + (y >> hadamard_shift_y[size])
+ + hadamard_offset[size];
+ uint64_t res = h->mb.pic.fenc_hadamard_cache[cache_index];
+ if( res )
+ return res - 1;
+ else
+ {
+ pixel *fenc = h->mb.pic.p_fenc[0] + x + y*FENC_STRIDE;
+ res = h->pixf.hadamard_ac[size]( fenc, FENC_STRIDE );
+ h->mb.pic.fenc_hadamard_cache[cache_index] = res + 1;
+ return res;
+ }
}
-static int ssd_plane( x264_t *h, int size, int p, int x, int y )
+static ALWAYS_INLINE int cached_satd( x264_t *h, int size, int x, int y )
{
- return h->pixf.ssd[size]( h->mb.pic.p_fenc[p] + x+y*FENC_STRIDE, FENC_STRIDE,
- h->mb.pic.p_fdec[p] + x+y*FDEC_STRIDE, FDEC_STRIDE );
+ static const uint8_t satd_shift_x[3] = {3, 2, 2};
+ static const uint8_t satd_shift_y[3] = {2-1, 3-2, 2-2};
+ static const uint8_t satd_offset[3] = {0, 8, 16};
+ ALIGNED_16( static pixel zero[16] );
+ int cache_index = (x >> satd_shift_x[size - PIXEL_8x4]) + (y >> satd_shift_y[size - PIXEL_8x4])
+ + satd_offset[size - PIXEL_8x4];
+ int res = h->mb.pic.fenc_satd_cache[cache_index];
+ if( res )
+ return res - 1;
+ else
+ {
+ pixel *fenc = h->mb.pic.p_fenc[0] + x + y*FENC_STRIDE;
+ int dc = h->pixf.sad[size]( fenc, FENC_STRIDE, zero, 0 ) >> 1;
+ res = h->pixf.satd[size]( fenc, FENC_STRIDE, zero, 0 ) - dc;
+ h->mb.pic.fenc_satd_cache[cache_index] = res + 1;
+ return res;
+ }
+}
+
+/* Psy RD distortion metric: SSD plus "Absolute Difference of Complexities" */
+/* SATD and SA8D are used to measure block complexity. */
+/* The difference between SATD and SA8D scores are both used to avoid bias from the DCT size. Using SATD */
+/* only, for example, results in overusage of 8x8dct, while the opposite occurs when using SA8D. */
+
+/* FIXME: Is there a better metric than averaged SATD/SA8D difference for complexity difference? */
+/* Hadamard transform is recursive, so a SATD+SA8D can be done faster by taking advantage of this fact. */
+/* This optimization can also be used in non-RD transform decision. */
+
+static inline int ssd_plane( x264_t *h, int size, int p, int x, int y )
+{
+ ALIGNED_16(static pixel zero[16]);
+ int satd = 0;
+ pixel *fdec = h->mb.pic.p_fdec[p] + x + y*FDEC_STRIDE;
+ pixel *fenc = h->mb.pic.p_fenc[p] + x + y*FENC_STRIDE;
+ if( p == 0 && h->mb.i_psy_rd )
+ {
+ /* If the plane is smaller than 8x8, we can't do an SA8D; this probably isn't a big problem. */
+ if( size <= PIXEL_8x8 )
+ {
+ uint64_t fdec_acs = h->pixf.hadamard_ac[size]( fdec, FDEC_STRIDE );
+ uint64_t fenc_acs = cached_hadamard( h, size, x, y );
+ satd = abs((int32_t)fdec_acs - (int32_t)fenc_acs)
+ + abs((int32_t)(fdec_acs>>32) - (int32_t)(fenc_acs>>32));
+ satd >>= 1;
+ }
+ else
+ {
+ int dc = h->pixf.sad[size]( fdec, FDEC_STRIDE, zero, 0 ) >> 1;
+ satd = abs(h->pixf.satd[size]( fdec, FDEC_STRIDE, zero, 0 ) - dc - cached_satd( h, size, x, y ));
+ }
+ satd = (satd * h->mb.i_psy_rd * h->mb.i_psy_rd_lambda + 128) >> 8;
+ }
+ return h->pixf.ssd[size](fenc, FENC_STRIDE, fdec, FDEC_STRIDE) + satd;
+}
+
+static inline int ssd_mb( x264_t *h )
+{
+ int chromassd = ssd_plane(h, PIXEL_8x8, 1, 0, 0) + ssd_plane(h, PIXEL_8x8, 2, 0, 0);
+ chromassd = ((uint64_t)chromassd * h->mb.i_chroma_lambda2_offset + 128) >> 8;
+ return ssd_plane(h, PIXEL_16x16, 0, 0, 0) + chromassd;
}
static int x264_rd_cost_mb( x264_t *h, int i_lambda2 )
int b_transform_bak = h->mb.b_transform_8x8;
int i_ssd;
int i_bits;
+ int type_bak = h->mb.i_type;
x264_macroblock_encode( h );
+ if( h->mb.b_deblock_rdo )
+ x264_macroblock_deblock( h );
+
i_ssd = ssd_mb( h );
if( IS_SKIP( h->mb.i_type ) )
{
- i_bits = 1 * i_lambda2;
+ i_bits = (1 * i_lambda2 + 128) >> 8;
}
else if( h->param.b_cabac )
{
x264_cabac_t cabac_tmp;
- h->mc.memcpy_aligned( &cabac_tmp, &h->cabac, offsetof(x264_cabac_t,i_low) );
+ COPY_CABAC;
x264_macroblock_size_cabac( h, &cabac_tmp );
- i_bits = ( cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
+ i_bits = ( (uint64_t)cabac_tmp.f8_bits_encoded * i_lambda2 + 32768 ) >> 16;
}
else
{
- bs_t bs_tmp = h->out.bs;
- bs_tmp.i_bits_encoded = 0;
- x264_macroblock_size_cavlc( h, &bs_tmp );
- i_bits = bs_tmp.i_bits_encoded * i_lambda2;
+ x264_macroblock_size_cavlc( h );
+ i_bits = ( h->out.bs.i_bits_encoded * i_lambda2 + 128 ) >> 8;
}
h->mb.b_transform_8x8 = b_transform_bak;
+ h->mb.i_type = type_bak;
return i_ssd + i_bits;
}
-int x264_rd_cost_part( x264_t *h, int i_lambda2, int i8, int i_pixel )
+/* For small partitions (i.e. those using at most one DCT category's worth of CABAC states),
+ * it's faster to copy the individual parts than to perform a whole CABAC_COPY. */
+static ALWAYS_INLINE void x264_copy_cabac_part( x264_t *h, x264_cabac_t *cb, int cat, int intra )
+{
+ if( intra )
+ COPY_CABAC_PART( 68, 2 ); //intra pred mode
+ else
+ COPY_CABAC_PART( 40, 16 ); //mvd, rounded up to 16 bytes
+
+ /* 8x8dct writes CBP, while non-8x8dct writes CBF */
+ if( cat != DCT_LUMA_8x8 )
+ COPY_CABAC_PART( 85 + cat * 4, 4 );
+ else
+ COPY_CABAC_PART( 73, 4 );
+
+ /* Really should be 15 bytes, but rounding up a byte saves some
+ * instructions and is faster, and copying extra data doesn't hurt. */
+ COPY_CABAC_PART( significant_coeff_flag_offset[h->mb.b_interlaced][cat], 16 );
+ COPY_CABAC_PART( last_coeff_flag_offset[h->mb.b_interlaced][cat], 16 );
+ COPY_CABAC_PART( coeff_abs_level_m1_offset[cat], 10 );
+ cb->f8_bits_encoded = 0;
+}
+
+/* partition RD functions use 8 bits more precision to avoid large rounding errors at low QPs */
+
+static uint64_t x264_rd_cost_subpart( x264_t *h, int i_lambda2, int i4, int i_pixel )
+{
+ uint64_t i_ssd, i_bits;
+
+ x264_macroblock_encode_p4x4( h, i4 );
+ if( i_pixel == PIXEL_8x4 )
+ x264_macroblock_encode_p4x4( h, i4+1 );
+ if( i_pixel == PIXEL_4x8 )
+ x264_macroblock_encode_p4x4( h, i4+2 );
+
+ i_ssd = ssd_plane( h, i_pixel, 0, block_idx_x[i4]*4, block_idx_y[i4]*4 );
+
+ if( h->param.b_cabac )
+ {
+ x264_cabac_t cabac_tmp;
+ x264_copy_cabac_part( h, &cabac_tmp, DCT_LUMA_4x4, 0 );
+ x264_subpartition_size_cabac( h, &cabac_tmp, i4, i_pixel );
+ i_bits = ( (uint64_t)cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
+ }
+ else
+ i_bits = x264_subpartition_size_cavlc( h, i4, i_pixel );
+
+ return (i_ssd<<8) + i_bits;
+}
+
+uint64_t x264_rd_cost_part( x264_t *h, int i_lambda2, int i4, int i_pixel )
{
- int i_ssd, i_bits;
+ uint64_t i_ssd, i_bits;
+ int i8 = i4 >> 2;
+ int chromassd;
if( i_pixel == PIXEL_16x16 )
{
- int type_bak = h->mb.i_type;
int i_cost = x264_rd_cost_mb( h, i_lambda2 );
- h->mb.i_type = type_bak;
return i_cost;
}
+ if( i_pixel > PIXEL_8x8 )
+ return x264_rd_cost_subpart( h, i_lambda2, i4, i_pixel );
+
+ h->mb.i_cbp_luma = 0;
+
x264_macroblock_encode_p8x8( h, i8 );
if( i_pixel == PIXEL_16x8 )
x264_macroblock_encode_p8x8( h, i8+1 );
if( i_pixel == PIXEL_8x16 )
x264_macroblock_encode_p8x8( h, i8+2 );
- i_ssd = ssd_plane( h, i_pixel, 0, (i8&1)*8, (i8>>1)*8 )
- + ssd_plane( h, i_pixel+3, 1, (i8&1)*4, (i8>>1)*4 )
- + ssd_plane( h, i_pixel+3, 2, (i8&1)*4, (i8>>1)*4 );
+ chromassd = ssd_plane( h, i_pixel+3, 1, (i8&1)*4, (i8>>1)*4 )
+ + ssd_plane( h, i_pixel+3, 2, (i8&1)*4, (i8>>1)*4 );
+ chromassd = ((uint64_t)chromassd * h->mb.i_chroma_lambda2_offset + 128) >> 8;
+ i_ssd = ssd_plane( h, i_pixel, 0, (i8&1)*8, (i8>>1)*8 ) + chromassd;
if( h->param.b_cabac )
{
x264_cabac_t cabac_tmp;
- h->mc.memcpy_aligned( &cabac_tmp, &h->cabac, offsetof(x264_cabac_t,i_low) );
+ COPY_CABAC;
x264_partition_size_cabac( h, &cabac_tmp, i8, i_pixel );
- i_bits = ( cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
+ i_bits = ( (uint64_t)cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
}
else
- {
i_bits = x264_partition_size_cavlc( h, i8, i_pixel ) * i_lambda2;
- }
- return i_ssd + i_bits;
+ return (i_ssd<<8) + i_bits;
}
-int x264_rd_cost_i8x8( x264_t *h, int i_lambda2, int i8, int i_mode )
+static uint64_t x264_rd_cost_i8x8( x264_t *h, int i_lambda2, int i8, int i_mode )
{
- int i_ssd, i_bits;
+ uint64_t i_ssd, i_bits;
+ h->mb.i_cbp_luma &= ~(1<<i8);
+ h->mb.b_transform_8x8 = 1;
x264_mb_encode_i8x8( h, i8, h->mb.i_qp );
i_ssd = ssd_plane( h, PIXEL_8x8, 0, (i8&1)*8, (i8>>1)*8 );
if( h->param.b_cabac )
{
x264_cabac_t cabac_tmp;
- h->mc.memcpy_aligned( &cabac_tmp, &h->cabac, offsetof(x264_cabac_t,i_low) );
+ x264_copy_cabac_part( h, &cabac_tmp, DCT_LUMA_8x8, 1 );
x264_partition_i8x8_size_cabac( h, &cabac_tmp, i8, i_mode );
- i_bits = ( cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
+ i_bits = ( (uint64_t)cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
}
else
- {
i_bits = x264_partition_i8x8_size_cavlc( h, i8, i_mode ) * i_lambda2;
- }
- return i_ssd + i_bits;
+ return (i_ssd<<8) + i_bits;
}
-int x264_rd_cost_i4x4( x264_t *h, int i_lambda2, int i4, int i_mode )
+static uint64_t x264_rd_cost_i4x4( x264_t *h, int i_lambda2, int i4, int i_mode )
{
- int i_ssd, i_bits;
+ uint64_t i_ssd, i_bits;
x264_mb_encode_i4x4( h, i4, h->mb.i_qp );
i_ssd = ssd_plane( h, PIXEL_4x4, 0, block_idx_x[i4]*4, block_idx_y[i4]*4 );
if( h->param.b_cabac )
{
x264_cabac_t cabac_tmp;
- h->mc.memcpy_aligned( &cabac_tmp, &h->cabac, offsetof(x264_cabac_t,i_low) );
-
+ x264_copy_cabac_part( h, &cabac_tmp, DCT_LUMA_4x4, 1 );
x264_partition_i4x4_size_cabac( h, &cabac_tmp, i4, i_mode );
- i_bits = ( cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
+ i_bits = ( (uint64_t)cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
}
else
- {
i_bits = x264_partition_i4x4_size_cavlc( h, i4, i_mode ) * i_lambda2;
- }
- return i_ssd + i_bits;
+ return (i_ssd<<8) + i_bits;
}
-int x264_rd_cost_i8x8_chroma( x264_t *h, int i_lambda2, int i_mode, int b_dct )
+static uint64_t x264_rd_cost_i8x8_chroma( x264_t *h, int i_lambda2, int i_mode, int b_dct )
{
- int i_ssd, i_bits;
+ uint64_t i_ssd, i_bits;
if( b_dct )
x264_mb_encode_8x8_chroma( h, 0, h->mb.i_chroma_qp );
if( h->param.b_cabac )
{
x264_cabac_t cabac_tmp;
- h->mc.memcpy_aligned( &cabac_tmp, &h->cabac, offsetof(x264_cabac_t,i_low) );
+ COPY_CABAC;
x264_i8x8_chroma_size_cabac( h, &cabac_tmp );
- i_bits = ( cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
+ i_bits = ( (uint64_t)cabac_tmp.f8_bits_encoded * i_lambda2 + 128 ) >> 8;
}
else
- {
i_bits = x264_i8x8_chroma_size_cavlc( h ) * i_lambda2;
- }
- return i_ssd + i_bits;
+ return (i_ssd<<8) + i_bits;
}
/****************************************************************************
* Trellis RD quantization
#define SSD_WEIGHT_BITS 5
#define LAMBDA_BITS 4
-/* precalculate the cost of coding abs_level_m1 */
-void x264_rdo_init( )
+/* precalculate the cost of coding various combinations of bits in a single context */
+void x264_rdo_init( void )
{
- int i_prefix;
- int i_ctx;
- for( i_prefix = 0; i_prefix < 15; i_prefix++ )
+ for( int i_prefix = 0; i_prefix < 15; i_prefix++ )
{
- for( i_ctx = 0; i_ctx < 128; i_ctx++ )
+ for( int i_ctx = 0; i_ctx < 128; i_ctx++ )
{
int f8_bits = 0;
uint8_t ctx = i_ctx;
- int i;
- for( i = 1; i < i_prefix; i++ )
+ for( int i = 1; i < i_prefix; i++ )
f8_bits += x264_cabac_size_decision2( &ctx, 1 );
if( i_prefix > 0 && i_prefix < 14 )
f8_bits += x264_cabac_size_decision2( &ctx, 0 );
f8_bits += 1 << CABAC_SIZE_BITS; //sign
- cabac_prefix_size[i_prefix][i_ctx] = f8_bits;
- cabac_prefix_transition[i_prefix][i_ctx] = ctx;
+ cabac_size_unary[i_prefix][i_ctx] = f8_bits;
+ cabac_transition_unary[i_prefix][i_ctx] = ctx;
}
}
-}
+ for( int i_ctx = 0; i_ctx < 128; i_ctx++ )
+ {
+ int f8_bits = 0;
+ uint8_t ctx = i_ctx;
-// node ctx: 0..3: abslevel1 (with abslevelgt1 == 0).
-// 4..7: abslevelgt1 + 3 (and abslevel1 doesn't matter).
-/* map node ctx => cabac ctx for level=1 */
-static const int coeff_abs_level1_ctx[8] = { 1, 2, 3, 4, 0, 0, 0, 0 };
-/* map node ctx => cabac ctx for level>1 */
-static const int coeff_abs_levelgt1_ctx[8] = { 5, 5, 5, 5, 6, 7, 8, 9 };
-static const int coeff_abs_level_transition[2][8] = {
-/* update node.ctx after coding a level=1 */
- { 1, 2, 3, 3, 4, 5, 6, 7 },
-/* update node.ctx after coding a level>1 */
- { 4, 4, 4, 4, 5, 6, 7, 7 }
-};
-
-// should the intra and inter lambdas be different?
-// I'm just matching the behaviour of deadzone quant.
-static const int lambda2_tab[2][52] = {
- // inter lambda = .85 * .85 * 2**(qp/3. + 10 - LAMBDA_BITS)
- { 46, 58, 73, 92, 117, 147,
- 185, 233, 294, 370, 466, 587,
- 740, 932, 1174, 1480, 1864, 2349,
- 2959, 3728, 4697, 5918, 7457, 9395,
- 11837, 14914, 18790, 23674, 29828, 37581,
- 47349, 59656, 75163, 94699, 119313, 150326,
- 189399, 238627, 300652, 378798, 477255, 601304,
- 757596, 954511, 1202608, 1515192, 1909022, 2405217,
- 3030384, 3818045, 4810435, 6060769 },
- // intra lambda = .65 * .65 * 2**(qp/3. + 10 - LAMBDA_BITS)
- { 27, 34, 43, 54, 68, 86,
- 108, 136, 172, 216, 273, 343,
- 433, 545, 687, 865, 1090, 1374,
- 1731, 2180, 2747, 3461, 4361, 5494,
- 6922, 8721, 10988, 13844, 17442, 21976,
- 27688, 34885, 43953, 55377, 69771, 87906,
- 110755, 139543, 175813, 221511, 279087, 351627,
- 443023, 558174, 703255, 886046, 1116348, 1406511,
- 1772093, 2232697, 2813022, 3544186 }
-};
+ for( int i = 0; i < 5; i++ )
+ f8_bits += x264_cabac_size_decision2( &ctx, 1 );
+ f8_bits += 1 << CABAC_SIZE_BITS; //sign
+
+ cabac_size_5ones[i_ctx] = f8_bits;
+ cabac_transition_5ones[i_ctx] = ctx;
+ }
+}
typedef struct {
- uint64_t score;
+ int64_t score;
int level_idx; // index into level_tree[]
uint8_t cabac_state[10]; //just the contexts relevant to coding abs_level_m1
} trellis_node_t;
// TODO:
-// support chroma and i16x16 DC
// save cabac state between blocks?
// use trellis' RD score instead of x264_mb_decimate_score?
// code 8x8 sig/last flags forwards with deadzone and save the contexts at
// comparable to the input. so unquant is the direct inverse of quant,
// and uses the dct scaling factors, not the idct ones.
-static void quant_trellis_cabac( x264_t *h, int16_t *dct,
- const uint16_t *quant_mf, const int *unquant_mf,
- const int *coef_weight, const uint8_t *zigzag,
- int i_ctxBlockCat, int i_lambda2, int b_ac, int i_coefs )
+static ALWAYS_INLINE
+int quant_trellis_cabac( x264_t *h, dctcoef *dct,
+ const uint16_t *quant_mf, const int *unquant_mf,
+ const int *coef_weight, const uint8_t *zigzag,
+ int ctx_block_cat, int i_lambda2, int b_ac,
+ int dc, int i_coefs, int idx )
{
int abs_coefs[64], signs[64];
trellis_node_t nodes[2][8];
trellis_node_t *nodes_cur = nodes[0];
trellis_node_t *nodes_prev = nodes[1];
trellis_node_t *bnode;
- uint8_t cabac_state_sig[64];
- uint8_t cabac_state_last[64];
const int b_interlaced = h->mb.b_interlaced;
+ uint8_t *cabac_state_sig = &h->cabac.state[ significant_coeff_flag_offset[b_interlaced][ctx_block_cat] ];
+ uint8_t *cabac_state_last = &h->cabac.state[ last_coeff_flag_offset[b_interlaced][ctx_block_cat] ];
const int f = 1 << 15; // no deadzone
int i_last_nnz;
- int i, j;
+ int i;
// (# of coefs) * (# of ctx) * (# of levels tried) = 1024
// we don't need to keep all of those: (# of coefs) * (# of ctx) would be enough,
/* init coefs */
for( i = i_coefs-1; i >= b_ac; i-- )
- if( (unsigned)(dct[zigzag[i]] * quant_mf[zigzag[i]] + f-1) >= 2*f )
+ if( (unsigned)(dct[zigzag[i]] * (dc?quant_mf[0]>>1:quant_mf[zigzag[i]]) + f-1) >= 2*f )
break;
if( i < b_ac )
{
- memset( dct, 0, i_coefs * sizeof(*dct) );
- return;
+ /* We only need to zero an empty 4x4 block. 8x8 can be
+ implicitly emptied via zero nnz, as can dc. */
+ if( i_coefs == 16 && !dc )
+ memset( dct, 0, 16 * sizeof(dctcoef) );
+ return 0;
}
i_last_nnz = i;
}
/* init trellis */
- for( i = 1; i < 8; i++ )
- nodes_cur[i].score = TRELLIS_SCORE_MAX;
+ for( int j = 1; j < 8; j++ )
+ nodes_cur[j].score = TRELLIS_SCORE_MAX;
nodes_cur[0].score = 0;
nodes_cur[0].level_idx = 0;
level_tree[0].abs_level = 0;
// in 8x8 blocks, some positions share contexts, so we'll just have to hope that
// cabac isn't too sensitive.
- if( i_coefs == 64 )
- {
- const uint8_t *ctx_sig = &h->cabac.state[ significant_coeff_flag_offset[b_interlaced][i_ctxBlockCat] ];
- const uint8_t *ctx_last = &h->cabac.state[ last_coeff_flag_offset[b_interlaced][i_ctxBlockCat] ];
- for( i = 0; i < 63; i++ )
- {
- cabac_state_sig[i] = ctx_sig[ significant_coeff_flag_offset_8x8[b_interlaced][i] ];
- cabac_state_last[i] = ctx_last[ last_coeff_flag_offset_8x8[i] ];
- }
- }
- else
- {
- memcpy( cabac_state_sig, &h->cabac.state[ significant_coeff_flag_offset[b_interlaced][i_ctxBlockCat] ], 15 );
- memcpy( cabac_state_last, &h->cabac.state[ last_coeff_flag_offset[b_interlaced][i_ctxBlockCat] ], 15 );
- }
- memcpy( nodes_cur[0].cabac_state, &h->cabac.state[ coeff_abs_level_m1_offset[i_ctxBlockCat] ], 10 );
+ memcpy( nodes_cur[0].cabac_state, &h->cabac.state[ coeff_abs_level_m1_offset[ctx_block_cat] ], 10 );
for( i = i_last_nnz; i >= b_ac; i-- )
{
int i_coef = abs_coefs[i];
- int q = ( f + i_coef * quant_mf[zigzag[i]] ) >> 16;
- int abs_level;
+ int q = ( f + i_coef * (dc?quant_mf[0]>>1:quant_mf[zigzag[i]]) ) >> 16;
int cost_sig[2], cost_last[2];
trellis_node_t n;
{
// no need to calculate ssd of 0s: it's the same in all nodes.
// no need to modify level_tree for ctx=0: it starts with an infinite loop of 0s.
- const uint32_t cost_sig0 = x264_cabac_size_decision_noup( &cabac_state_sig[i], 0 )
+ int sigindex = i_coefs == 64 ? significant_coeff_flag_offset_8x8[b_interlaced][i] : i;
+ const uint32_t cost_sig0 = x264_cabac_size_decision_noup2( &cabac_state_sig[sigindex], 0 )
* (uint64_t)i_lambda2 >> ( CABAC_SIZE_BITS - LAMBDA_BITS );
- for( j = 1; j < 8; j++ )
+ for( int j = 1; j < 8; j++ )
{
if( nodes_cur[j].score != TRELLIS_SCORE_MAX )
{
XCHG( trellis_node_t*, nodes_cur, nodes_prev );
- for( j = 0; j < 8; j++ )
+ for( int j = 0; j < 8; j++ )
nodes_cur[j].score = TRELLIS_SCORE_MAX;
if( i < i_coefs-1 )
{
- cost_sig[0] = x264_cabac_size_decision_noup( &cabac_state_sig[i], 0 );
- cost_sig[1] = x264_cabac_size_decision_noup( &cabac_state_sig[i], 1 );
- cost_last[0] = x264_cabac_size_decision_noup( &cabac_state_last[i], 0 );
- cost_last[1] = x264_cabac_size_decision_noup( &cabac_state_last[i], 1 );
+ int sigindex = i_coefs == 64 ? significant_coeff_flag_offset_8x8[b_interlaced][i] : i;
+ int lastindex = i_coefs == 64 ? last_coeff_flag_offset_8x8[i] : i;
+ cost_sig[0] = x264_cabac_size_decision_noup2( &cabac_state_sig[sigindex], 0 );
+ cost_sig[1] = x264_cabac_size_decision_noup2( &cabac_state_sig[sigindex], 1 );
+ cost_last[0] = x264_cabac_size_decision_noup2( &cabac_state_last[lastindex], 0 );
+ cost_last[1] = x264_cabac_size_decision_noup2( &cabac_state_last[lastindex], 1 );
}
else
{
// but it's only around .003 dB, and skipping them ~doubles the speed of trellis.
// could also try q-2: that sometimes helps, but also sometimes decimates blocks
// that are better left coded, especially at QP > 40.
- for( abs_level = q; abs_level >= q-1; abs_level-- )
+ for( int abs_level = q; abs_level >= q-1; abs_level-- )
{
- int d = i_coef - ((unquant_mf[zigzag[i]] * abs_level + 128) >> 8);
- uint64_t ssd = (int64_t)d*d * coef_weight[i];
+ int unquant_abs_level = (((dc?unquant_mf[0]<<1:unquant_mf[zigzag[i]]) * abs_level + 128) >> 8);
+ int d = i_coef - unquant_abs_level;
+ int64_t ssd;
+ /* Psy trellis: bias in favor of higher AC coefficients in the reconstructed frame. */
+ if( h->mb.i_psy_trellis && i && !dc && ctx_block_cat != DCT_CHROMA_AC )
+ {
+ int orig_coef = (i_coefs == 64) ? h->mb.pic.fenc_dct8[idx][zigzag[i]] : h->mb.pic.fenc_dct4[idx][zigzag[i]];
+ int predicted_coef = orig_coef - i_coef * signs[i];
+ int psy_value = h->mb.i_psy_trellis * abs(predicted_coef + unquant_abs_level * signs[i]);
+ int psy_weight = (i_coefs == 64) ? x264_dct8_weight_tab[zigzag[i]] : x264_dct4_weight_tab[zigzag[i]];
+ ssd = (int64_t)d*d * coef_weight[i] - psy_weight * psy_value;
+ }
+ else
+ /* FIXME: for i16x16 dc is this weight optimal? */
+ ssd = (int64_t)d*d * (dc?256:coef_weight[i]);
- for( j = 0; j < 8; j++ )
+ for( int j = 0; j < 8; j++ )
{
int node_ctx = j;
if( nodes_prev[j].score == TRELLIS_SCORE_MAX )
if( i_prefix > 0 )
{
uint8_t *ctx = &n.cabac_state[coeff_abs_levelgt1_ctx[node_ctx]];
- f8_bits += cabac_prefix_size[i_prefix][*ctx];
- *ctx = cabac_prefix_transition[i_prefix][*ctx];
+ f8_bits += cabac_size_unary[i_prefix][*ctx];
+ *ctx = cabac_transition_unary[i_prefix][*ctx];
if( abs_level >= 15 )
- f8_bits += bs_size_ue( abs_level - 15 ) << CABAC_SIZE_BITS;
+ f8_bits += bs_size_ue_big( abs_level - 15 ) << CABAC_SIZE_BITS;
node_ctx = coeff_abs_level_transition[1][node_ctx];
}
else
n.score += (uint64_t)f8_bits * i_lambda2 >> ( CABAC_SIZE_BITS - LAMBDA_BITS );
}
- n.score += ssd;
+ if( j || i || dc )
+ n.score += ssd;
+ /* Optimize rounding for DC coefficients in DC-only luma 4x4/8x8 blocks. */
+ else
+ {
+ d = i_coef * signs[0] - ((unquant_abs_level * signs[0] + 8)&~15);
+ n.score += (int64_t)d*d * coef_weight[i];
+ }
/* save the node if it's better than any existing node with the same cabac ctx */
if( n.score < nodes_cur[node_ctx].score )
/* output levels from the best path through the trellis */
bnode = &nodes_cur[0];
- for( j = 1; j < 8; j++ )
+ for( int j = 1; j < 8; j++ )
if( nodes_cur[j].score < bnode->score )
bnode = &nodes_cur[j];
- j = bnode->level_idx;
- for( i = b_ac; i < i_coefs; i++ )
+ if( bnode == &nodes_cur[0] )
{
- dct[zigzag[i]] = level_tree[j].abs_level * signs[i];
- j = level_tree[j].next;
+ if( i_coefs == 16 && !dc )
+ memset( dct, 0, 16 * sizeof(dctcoef) );
+ return 0;
}
+
+ int level = bnode->level_idx;
+ for( i = b_ac; level; i++ )
+ {
+ dct[zigzag[i]] = level_tree[level].abs_level * signs[i];
+ level = level_tree[level].next;
+ }
+ for( ; i < i_coefs; i++ )
+ dct[zigzag[i]] = 0;
+
+ return 1;
}
+/* FIXME: This is a gigantic hack. See below.
+ *
+ * CAVLC is much more difficult to trellis than CABAC.
+ *
+ * CABAC has only three states to track: significance map, last, and the
+ * level state machine.
+ * CAVLC, by comparison, has five: coeff_token (trailing + total),
+ * total_zeroes, zero_run, and the level state machine.
+ *
+ * I know of no paper that has managed to design a close-to-optimal trellis
+ * that covers all five of these and isn't exponential-time. As a result, this
+ * "trellis" isn't: it's just a QNS search. Patches welcome for something better.
+ * It's actually surprisingly fast, albeit not quite optimal. It's pretty close
+ * though; since CAVLC only has 2^16 possible rounding modes (assuming only two
+ * roundings as options), a bruteforce search is feasible. Testing shows
+ * that this QNS is reasonably close to optimal in terms of compression.
+ *
+ * TODO:
+ * Don't bother changing large coefficients when it wouldn't affect bit cost
+ * (e.g. only affecting bypassed suffix bits).
+ * Don't re-run all parts of CAVLC bit cost calculation when not necessary.
+ * e.g. when changing a coefficient from one non-zero value to another in
+ * such a way that trailing ones and suffix length isn't affected. */
+static ALWAYS_INLINE
+int quant_trellis_cavlc( x264_t *h, dctcoef *dct,
+ const uint16_t *quant_mf, const int *unquant_mf,
+ const int *coef_weight, const uint8_t *zigzag,
+ int ctx_block_cat, int i_lambda2, int b_ac,
+ int dc, int i_coefs, int idx, int b_8x8 )
+{
+ ALIGNED_16( dctcoef quant_coefs[2][16] );
+ ALIGNED_16( dctcoef coefs[16] ) = {0};
+ int delta_distortion[16];
+ int64_t score = 1ULL<<62;
+ int i, j;
+ const int f = 1<<15;
+ int nC = ctx_block_cat == DCT_CHROMA_DC ? 4 : ct_index[x264_mb_predict_non_zero_code( h, ctx_block_cat == DCT_LUMA_DC ? 0 : idx )];
+
+ /* Code for handling 8x8dct -> 4x4dct CAVLC munging. Input/output use a different
+ * step/start/end than internal processing. */
+ int step = 1;
+ int start = b_ac;
+ int end = i_coefs - 1;
+ if( b_8x8 )
+ {
+ start = idx&3;
+ end = 60 + start;
+ step = 4;
+ }
+
+ i_lambda2 <<= LAMBDA_BITS;
+
+ /* Find last non-zero coefficient. */
+ for( i = end; i >= start; i -= step )
+ if( (unsigned)(dct[zigzag[i]] * (dc?quant_mf[0]>>1:quant_mf[zigzag[i]]) + f-1) >= 2*f )
+ break;
+
+ if( i < start )
+ goto zeroblock;
+
+ /* Prepare for QNS search: calculate distortion caused by each DCT coefficient
+ * rounding to be searched.
+ *
+ * We only search two roundings (nearest and nearest-1) like in CABAC trellis,
+ * so we just store the difference in distortion between them. */
+ int i_last_nnz = b_8x8 ? i >> 2 : i;
+ int coef_mask = 0;
+ int round_mask = 0;
+ for( i = b_ac, j = start; i <= i_last_nnz; i++, j += step )
+ {
+ int coef = dct[zigzag[j]];
+ int abs_coef = abs(coef);
+ int sign = coef < 0 ? -1 : 1;
+ int nearest_quant = ( f + abs_coef * (dc?quant_mf[0]>>1:quant_mf[zigzag[j]]) ) >> 16;
+ quant_coefs[1][i] = quant_coefs[0][i] = sign * nearest_quant;
+ coefs[i] = quant_coefs[1][i];
+ if( nearest_quant )
+ {
+ /* We initialize the trellis with a deadzone halfway between nearest rounding
+ * and always-round-down. This gives much better results than initializing to either
+ * extreme.
+ * FIXME: should we initialize to the deadzones used by deadzone quant? */
+ int deadzone_quant = ( f/2 + abs_coef * (dc?quant_mf[0]>>1:quant_mf[zigzag[j]]) ) >> 16;
+ int unquant1 = (((dc?unquant_mf[0]<<1:unquant_mf[zigzag[j]]) * (nearest_quant-0) + 128) >> 8);
+ int unquant0 = (((dc?unquant_mf[0]<<1:unquant_mf[zigzag[j]]) * (nearest_quant-1) + 128) >> 8);
+ int d1 = abs_coef - unquant1;
+ int d0 = abs_coef - unquant0;
+ delta_distortion[i] = (d0*d0 - d1*d1) * (dc?256:coef_weight[j]);
+
+ /* Psy trellis: bias in favor of higher AC coefficients in the reconstructed frame. */
+ if( h->mb.i_psy_trellis && j && !dc && ctx_block_cat != DCT_CHROMA_AC )
+ {
+ int orig_coef = b_8x8 ? h->mb.pic.fenc_dct8[idx>>2][zigzag[j]] : h->mb.pic.fenc_dct4[idx][zigzag[j]];
+ int predicted_coef = orig_coef - coef;
+ int psy_weight = b_8x8 ? x264_dct8_weight_tab[zigzag[j]] : x264_dct4_weight_tab[zigzag[j]];
+ int psy_value0 = h->mb.i_psy_trellis * abs(predicted_coef + unquant0 * sign);
+ int psy_value1 = h->mb.i_psy_trellis * abs(predicted_coef + unquant1 * sign);
+ delta_distortion[i] += (psy_value0 - psy_value1) * psy_weight;
+ }
+
+ quant_coefs[0][i] = sign * (nearest_quant-1);
+ if( deadzone_quant != nearest_quant )
+ coefs[i] = quant_coefs[0][i];
+ else
+ round_mask |= 1 << i;
+ }
+ else
+ delta_distortion[i] = 0;
+ coef_mask |= (!!coefs[i]) << i;
+ }
+
+ /* Calculate the cost of the starting state. */
+ h->out.bs.i_bits_encoded = 0;
+ if( !coef_mask )
+ bs_write_vlc( &h->out.bs, x264_coeff0_token[nC] );
+ else
+ block_residual_write_cavlc_internal( h, ctx_block_cat, coefs + b_ac, nC );
+ score = (int64_t)h->out.bs.i_bits_encoded * i_lambda2;
-void x264_quant_4x4_trellis( x264_t *h, int16_t dct[4][4], int i_quant_cat,
- int i_qp, int i_ctxBlockCat, int b_intra )
+ /* QNS loop: pick the change that improves RD the most, apply it, repeat.
+ * coef_mask and round_mask are used to simplify tracking of nonzeroness
+ * and rounding modes chosen. */
+ while( 1 )
+ {
+ int64_t iter_score = score;
+ int iter_distortion_delta = 0;
+ int iter_coef = -1;
+ int iter_mask = coef_mask;
+ int iter_round = round_mask;
+ for( i = b_ac; i <= i_last_nnz; i++ )
+ {
+ if( !delta_distortion[i] )
+ continue;
+
+ /* Set up all the variables for this iteration. */
+ int cur_round = round_mask ^ (1 << i);
+ int round_change = (cur_round >> i)&1;
+ int old_coef = coefs[i];
+ int new_coef = quant_coefs[round_change][i];
+ int cur_mask = (coef_mask&~(1 << i))|(!!new_coef << i);
+ int cur_distortion_delta = delta_distortion[i] * (round_change ? -1 : 1);
+ int64_t cur_score = cur_distortion_delta;
+ coefs[i] = new_coef;
+
+ /* Count up bits. */
+ h->out.bs.i_bits_encoded = 0;
+ if( !cur_mask )
+ bs_write_vlc( &h->out.bs, x264_coeff0_token[nC] );
+ else
+ block_residual_write_cavlc_internal( h, ctx_block_cat, coefs + b_ac, nC );
+ cur_score += (int64_t)h->out.bs.i_bits_encoded * i_lambda2;
+
+ coefs[i] = old_coef;
+ if( cur_score < iter_score )
+ {
+ iter_score = cur_score;
+ iter_coef = i;
+ iter_mask = cur_mask;
+ iter_round = cur_round;
+ iter_distortion_delta = cur_distortion_delta;
+ }
+ }
+ if( iter_coef >= 0 )
+ {
+ score = iter_score - iter_distortion_delta;
+ coef_mask = iter_mask;
+ round_mask = iter_round;
+ coefs[iter_coef] = quant_coefs[((round_mask >> iter_coef)&1)][iter_coef];
+ /* Don't try adjusting coefficients we've already adjusted.
+ * Testing suggests this doesn't hurt results -- and sometimes actually helps. */
+ delta_distortion[iter_coef] = 0;
+ }
+ else
+ break;
+ }
+
+ if( coef_mask )
+ {
+ for( i = b_ac, j = start; i <= i_last_nnz; i++, j += step )
+ dct[zigzag[j]] = coefs[i];
+ for( ; j <= end; j += step )
+ dct[zigzag[j]] = 0;
+ return 1;
+ }
+
+zeroblock:
+ if( !dc )
+ {
+ if( b_8x8 )
+ for( i = start; i <= end; i+=step )
+ dct[zigzag[i]] = 0;
+ else
+ memset( dct, 0, 16*sizeof(dctcoef) );
+ }
+ return 0;
+}
+
+const static uint8_t x264_zigzag_scan2[4] = {0,1,2,3};
+
+int x264_quant_dc_trellis( x264_t *h, dctcoef *dct, int i_quant_cat,
+ int i_qp, int ctx_block_cat, int b_intra, int b_chroma )
{
- int b_ac = (i_ctxBlockCat == DCT_LUMA_AC);
- quant_trellis_cabac( h, (int16_t*)dct,
+ if( h->param.b_cabac )
+ return quant_trellis_cabac( h, dct,
+ h->quant4_mf[i_quant_cat][i_qp], h->unquant4_mf[i_quant_cat][i_qp],
+ NULL, ctx_block_cat==DCT_CHROMA_DC ? x264_zigzag_scan2 : x264_zigzag_scan4[h->mb.b_interlaced],
+ ctx_block_cat, h->mb.i_trellis_lambda2[b_chroma][b_intra], 0, 1, ctx_block_cat==DCT_CHROMA_DC ? 4 : 16, 0 );
+
+ return quant_trellis_cavlc( h, dct,
h->quant4_mf[i_quant_cat][i_qp], h->unquant4_mf[i_quant_cat][i_qp],
- x264_dct4_weight2_zigzag[h->mb.b_interlaced],
- x264_zigzag_scan4[h->mb.b_interlaced],
- i_ctxBlockCat, lambda2_tab[b_intra][i_qp], b_ac, 16 );
+ NULL, ctx_block_cat==DCT_CHROMA_DC ? x264_zigzag_scan2 : x264_zigzag_scan4[h->mb.b_interlaced],
+ ctx_block_cat, h->mb.i_trellis_lambda2[b_chroma][b_intra], 0, 1, ctx_block_cat==DCT_CHROMA_DC ? 4 : 16, 0, 0 );
}
-
-void x264_quant_8x8_trellis( x264_t *h, int16_t dct[8][8], int i_quant_cat,
- int i_qp, int b_intra )
+int x264_quant_4x4_trellis( x264_t *h, dctcoef *dct, int i_quant_cat,
+ int i_qp, int ctx_block_cat, int b_intra, int b_chroma, int idx )
{
- quant_trellis_cabac( h, (int16_t*)dct,
- h->quant8_mf[i_quant_cat][i_qp], h->unquant8_mf[i_quant_cat][i_qp],
- x264_dct8_weight2_zigzag[h->mb.b_interlaced],
- x264_zigzag_scan8[h->mb.b_interlaced],
- DCT_LUMA_8x8, lambda2_tab[b_intra][i_qp], 0, 64 );
+ int b_ac = (ctx_block_cat == DCT_LUMA_AC || ctx_block_cat == DCT_CHROMA_AC);
+ if( h->param.b_cabac )
+ return quant_trellis_cabac( h, dct,
+ h->quant4_mf[i_quant_cat][i_qp], h->unquant4_mf[i_quant_cat][i_qp],
+ x264_dct4_weight2_zigzag[h->mb.b_interlaced],
+ x264_zigzag_scan4[h->mb.b_interlaced],
+ ctx_block_cat, h->mb.i_trellis_lambda2[b_chroma][b_intra], b_ac, 0, 16, idx );
+
+ return quant_trellis_cavlc( h, dct,
+ h->quant4_mf[i_quant_cat][i_qp], h->unquant4_mf[i_quant_cat][i_qp],
+ x264_dct4_weight2_zigzag[h->mb.b_interlaced],
+ x264_zigzag_scan4[h->mb.b_interlaced],
+ ctx_block_cat, h->mb.i_trellis_lambda2[b_chroma][b_intra], b_ac, 0, 16, idx, 0 );
}
+int x264_quant_8x8_trellis( x264_t *h, dctcoef *dct, int i_quant_cat,
+ int i_qp, int b_intra, int idx )
+{
+ if( h->param.b_cabac )
+ {
+ return quant_trellis_cabac( h, dct,
+ h->quant8_mf[i_quant_cat][i_qp], h->unquant8_mf[i_quant_cat][i_qp],
+ x264_dct8_weight2_zigzag[h->mb.b_interlaced],
+ x264_zigzag_scan8[h->mb.b_interlaced],
+ DCT_LUMA_8x8, h->mb.i_trellis_lambda2[0][b_intra], 0, 0, 64, idx );
+ }
+
+ /* 8x8 CAVLC is split into 4 4x4 blocks */
+ int nzaccum = 0;
+ for( int i = 0; i < 4; i++ )
+ {
+ int nz = quant_trellis_cavlc( h, dct,
+ h->quant8_mf[i_quant_cat][i_qp], h->unquant8_mf[i_quant_cat][i_qp],
+ x264_dct8_weight2_zigzag[h->mb.b_interlaced],
+ x264_zigzag_scan8[h->mb.b_interlaced],
+ DCT_LUMA_4x4, h->mb.i_trellis_lambda2[0][b_intra], 0, 0, 16, idx*4+i, 1 );
+ /* Set up nonzero count for future calls */
+ h->mb.cache.non_zero_count[x264_scan8[idx*4+i]] = nz;
+ nzaccum |= nz;
+ }
+ return nzaccum;
+}
projects / x264 / blobdiff