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/*
* AltiVec optimizations for libjpeg-turbo
*
* Copyright (C) 2015, D. R. Commander. All Rights Reserved.
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
/* CHROMA DOWNSAMPLING */
#include "jsimd_altivec.h"
#include "jcsample.h"
void jsimd_h2v1_downsample_altivec(JDIMENSION image_width,
int max_v_samp_factor,
JDIMENSION v_samp_factor,
JDIMENSION width_in_blocks,
JSAMPARRAY input_data,
JSAMPARRAY output_data)
{
int outrow, outcol;
JDIMENSION output_cols = width_in_blocks * DCTSIZE;
JSAMPROW inptr, outptr;
__vector unsigned char this0, next0, out;
__vector unsigned short this0e, this0o, next0e, next0o, outl, outh;
/* Constants */
__vector unsigned short pw_bias = { __4X2(0, 1) },
pw_one = { __8X(1) };
__vector unsigned char even_odd_index =
{ 0, 2, 4, 6, 8, 10, 12, 14, 1, 3, 5, 7, 9, 11, 13, 15 },
pb_zero = { __16X(0) };
expand_right_edge(input_data, max_v_samp_factor, image_width,
output_cols * 2);
for (outrow = 0; outrow < v_samp_factor; outrow++) {
outptr = output_data[outrow];
inptr = input_data[outrow];
for (outcol = output_cols; outcol > 0;
outcol -= 16, inptr += 32, outptr += 16) {
this0 = vec_ld(0, inptr);
this0 = vec_perm(this0, this0, even_odd_index);
this0e = (__vector unsigned short)VEC_UNPACKHU(this0);
this0o = (__vector unsigned short)VEC_UNPACKLU(this0);
outl = vec_add(this0e, this0o);
outl = vec_add(outl, pw_bias);
outl = vec_sr(outl, pw_one);
if (outcol > 8) {
next0 = vec_ld(16, inptr);
next0 = vec_perm(next0, next0, even_odd_index);
next0e = (__vector unsigned short)VEC_UNPACKHU(next0);
next0o = (__vector unsigned short)VEC_UNPACKLU(next0);
outh = vec_add(next0e, next0o);
outh = vec_add(outh, pw_bias);
outh = vec_sr(outh, pw_one);
} else
outh = vec_splat_u16(0);
out = vec_pack(outl, outh);
vec_st(out, 0, outptr);
}
}
}
void
jsimd_h2v2_downsample_altivec(JDIMENSION image_width, int max_v_samp_factor,
JDIMENSION v_samp_factor,
JDIMENSION width_in_blocks,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
int inrow, outrow, outcol;
JDIMENSION output_cols = width_in_blocks * DCTSIZE;
JSAMPROW inptr0, inptr1, outptr;
__vector unsigned char this0, next0, this1, next1, out;
__vector unsigned short this0e, this0o, next0e, next0o, this1e, this1o,
next1e, next1o, out0l, out0h, out1l, out1h, outl, outh;
/* Constants */
__vector unsigned short pw_bias = { __4X2(1, 2) },
pw_two = { __8X(2) };
__vector unsigned char even_odd_index =
{ 0, 2, 4, 6, 8, 10, 12, 14, 1, 3, 5, 7, 9, 11, 13, 15 },
pb_zero = { __16X(0) };
expand_right_edge(input_data, max_v_samp_factor, image_width,
output_cols * 2);
for (inrow = 0, outrow = 0; outrow < v_samp_factor;
inrow += 2, outrow++) {
inptr0 = input_data[inrow];
inptr1 = input_data[inrow + 1];
outptr = output_data[outrow];
for (outcol = output_cols; outcol > 0;
outcol -= 16, inptr0 += 32, inptr1 += 32, outptr += 16) {
this0 = vec_ld(0, inptr0);
this0 = vec_perm(this0, this0, even_odd_index);
this0e = (__vector unsigned short)VEC_UNPACKHU(this0);
this0o = (__vector unsigned short)VEC_UNPACKLU(this0);
out0l = vec_add(this0e, this0o);
this1 = vec_ld(0, inptr1);
this1 = vec_perm(this1, this1, even_odd_index);
this1e = (__vector unsigned short)VEC_UNPACKHU(this1);
this1o = (__vector unsigned short)VEC_UNPACKLU(this1);
out1l = vec_add(this1e, this1o);
outl = vec_add(out0l, out1l);
outl = vec_add(outl, pw_bias);
outl = vec_sr(outl, pw_two);
if (outcol > 8) {
next0 = vec_ld(16, inptr0);
next0 = vec_perm(next0, next0, even_odd_index);
next0e = (__vector unsigned short)VEC_UNPACKHU(next0);
next0o = (__vector unsigned short)VEC_UNPACKLU(next0);
out0h = vec_add(next0e, next0o);
next1 = vec_ld(16, inptr1);
next1 = vec_perm(next1, next1, even_odd_index);
next1e = (__vector unsigned short)VEC_UNPACKHU(next1);
next1o = (__vector unsigned short)VEC_UNPACKLU(next1);
out1h = vec_add(next1e, next1o);
outh = vec_add(out0h, out1h);
outh = vec_add(outh, pw_bias);
outh = vec_sr(outh, pw_two);
} else
outh = vec_splat_u16(0);
out = vec_pack(outl, outh);
vec_st(out, 0, outptr);
}
}
}