;******************************************************************************
 ;* x86 optimized dithering format conversion
 ;* Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
 ;*

 ;* This file is part of FFmpeg.

 ;*

 ;* FFmpeg is free software; you can redistribute it and/or

 ;* modify it under the terms of the GNU Lesser General Public
 ;* License as published by the Free Software Foundation; either
 ;* version 2.1 of the License, or (at your option) any later version.
 ;*

 ;* FFmpeg is distributed in the hope that it will be useful,

 ;* but WITHOUT ANY WARRANTY; without even the implied warranty of
 ;* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 ;* Lesser General Public License for more details.
 ;*
 ;* You should have received a copy of the GNU Lesser General Public

 ;* License along with FFmpeg; if not, write to the Free Software

 ;* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 ;******************************************************************************
 
 %include "libavutil/x86/x86util.asm"
 
 SECTION_RODATA 32
 

 ; 1.0f / (2.0f * INT32_MAX)
 pf_dither_scale: times 8 dd 2.32830643762e-10
 

 pf_s16_scale: times 4 dd 32753.0
 

 SECTION .text

 
 ;------------------------------------------------------------------------------
 ; void ff_quantize(int16_t *dst, float *src, float *dither, int len);
 ;------------------------------------------------------------------------------
 
 INIT_XMM sse2
 cglobal quantize, 4,4,3, dst, src, dither, len
     lea         lenq, [2*lend]
     add         dstq, lenq
     lea         srcq, [srcq+2*lenq]
     lea      ditherq, [ditherq+2*lenq]
     neg         lenq
     mova          m2, [pf_s16_scale]
 .loop:
     mulps         m0, m2, [srcq+2*lenq]
     mulps         m1, m2, [srcq+2*lenq+mmsize]
     addps         m0, [ditherq+2*lenq]
     addps         m1, [ditherq+2*lenq+mmsize]
     cvtps2dq      m0, m0
     cvtps2dq      m1, m1
     packssdw      m0, m1
     mova     [dstq+lenq], m0
     add         lenq, mmsize
     jl .loop
     REP_RET

 
 ;------------------------------------------------------------------------------
 ; void ff_dither_int_to_float_rectangular(float *dst, int *src, int len)
 ;------------------------------------------------------------------------------
 
 %macro DITHER_INT_TO_FLOAT_RECTANGULAR 0
 cglobal dither_int_to_float_rectangular, 3,3,3, dst, src, len
     lea         lenq, [4*lend]
     add         srcq, lenq
     add         dstq, lenq
     neg         lenq
     mova          m0, [pf_dither_scale]
 .loop:
     cvtdq2ps      m1, [srcq+lenq]
     cvtdq2ps      m2, [srcq+lenq+mmsize]
     mulps         m1, m1, m0
     mulps         m2, m2, m0
     mova  [dstq+lenq], m1
     mova  [dstq+lenq+mmsize], m2
     add         lenq, 2*mmsize
     jl .loop
     REP_RET
 %endmacro
 
 INIT_XMM sse2
 DITHER_INT_TO_FLOAT_RECTANGULAR
 INIT_YMM avx
 DITHER_INT_TO_FLOAT_RECTANGULAR
 
 ;------------------------------------------------------------------------------
 ; void ff_dither_int_to_float_triangular(float *dst, int *src0, int len)
 ;------------------------------------------------------------------------------
 
 %macro DITHER_INT_TO_FLOAT_TRIANGULAR 0
 cglobal dither_int_to_float_triangular, 3,4,5, dst, src0, len, src1
     lea         lenq, [4*lend]
     lea        src1q, [src0q+2*lenq]
     add        src0q, lenq
     add         dstq, lenq
     neg         lenq
     mova          m0, [pf_dither_scale]
 .loop:
     cvtdq2ps      m1, [src0q+lenq]
     cvtdq2ps      m2, [src0q+lenq+mmsize]
     cvtdq2ps      m3, [src1q+lenq]
     cvtdq2ps      m4, [src1q+lenq+mmsize]
     addps         m1, m1, m3
     addps         m2, m2, m4
     mulps         m1, m1, m0
     mulps         m2, m2, m0
     mova  [dstq+lenq], m1
     mova  [dstq+lenq+mmsize], m2
     add         lenq, 2*mmsize
     jl .loop
     REP_RET
 %endmacro
 
 INIT_XMM sse2
 DITHER_INT_TO_FLOAT_TRIANGULAR
 INIT_YMM avx
 DITHER_INT_TO_FLOAT_TRIANGULAR