ffmpeg/libavcodec/hqxdsp.c

132 lines
3.8 KiB
C
Raw Normal View History

/*
* HQX DSP routines
*
* 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 <stdint.h>
#include "libavutil/common.h"
#include "hqxdsp.h"
static inline void idct_col(int16_t *blk, const uint8_t *quant)
{
int t0, t1, t2, t3, t4, t5, t6, t7, t8, t9, tA, tB, tC, tD, tE, tF;
int t10, t11, t12, t13;
int s0, s1, s2, s3, s4, s5, s6, s7;
s0 = (int) blk[0 * 8] * quant[0 * 8];
s1 = (int) blk[1 * 8] * quant[1 * 8];
s2 = (int) blk[2 * 8] * quant[2 * 8];
s3 = (int) blk[3 * 8] * quant[3 * 8];
s4 = (int) blk[4 * 8] * quant[4 * 8];
s5 = (int) blk[5 * 8] * quant[5 * 8];
s6 = (int) blk[6 * 8] * quant[6 * 8];
s7 = (int) blk[7 * 8] * quant[7 * 8];
t0 = (s3 * 19266 + s5 * 12873) >> 15;
t1 = (s5 * 19266 - s3 * 12873) >> 15;
t2 = ((s7 * 4520 + s1 * 22725) >> 15) - t0;
t3 = ((s1 * 4520 - s7 * 22725) >> 15) - t1;
t4 = t0 * 2 + t2;
t5 = t1 * 2 + t3;
t6 = t2 - t3;
t7 = t3 * 2 + t6;
t8 = (t6 * 11585) >> 14;
t9 = (t7 * 11585) >> 14;
tA = (s2 * 8867 - s6 * 21407) >> 14;
tB = (s6 * 8867 + s2 * 21407) >> 14;
tC = (s0 >> 1) - (s4 >> 1);
tD = (s4 >> 1) * 2 + tC;
tE = tC - (tA >> 1);
tF = tD - (tB >> 1);
t10 = tF - t5;
t11 = tE - t8;
t12 = tE + (tA >> 1) * 2 - t9;
t13 = tF + (tB >> 1) * 2 - t4;
blk[0 * 8] = t13 + t4 * 2;
blk[1 * 8] = t12 + t9 * 2;
blk[2 * 8] = t11 + t8 * 2;
blk[3 * 8] = t10 + t5 * 2;
blk[4 * 8] = t10;
blk[5 * 8] = t11;
blk[6 * 8] = t12;
blk[7 * 8] = t13;
}
static inline void idct_row(int16_t *blk)
{
int t0, t1, t2, t3, t4, t5, t6, t7, t8, t9, tA, tB, tC, tD, tE, tF;
int t10, t11, t12, t13;
t0 = (blk[3] * 19266 + blk[5] * 12873) >> 14;
t1 = (blk[5] * 19266 - blk[3] * 12873) >> 14;
t2 = ((blk[7] * 4520 + blk[1] * 22725) >> 14) - t0;
t3 = ((blk[1] * 4520 - blk[7] * 22725) >> 14) - t1;
t4 = t0 * 2 + t2;
t5 = t1 * 2 + t3;
t6 = t2 - t3;
t7 = t3 * 2 + t6;
t8 = (t6 * 11585) >> 14;
t9 = (t7 * 11585) >> 14;
tA = (blk[2] * 8867 - blk[6] * 21407) >> 14;
tB = (blk[6] * 8867 + blk[2] * 21407) >> 14;
tC = blk[0] - blk[4];
tD = blk[4] * 2 + tC;
tE = tC - tA;
tF = tD - tB;
t10 = tF - t5;
t11 = tE - t8;
t12 = tE + tA * 2 - t9;
t13 = tF + tB * 2 - t4;
blk[0] = (t13 + t4 * 2 + 4) >> 3;
blk[1] = (t12 + t9 * 2 + 4) >> 3;
blk[2] = (t11 + t8 * 2 + 4) >> 3;
blk[3] = (t10 + t5 * 2 + 4) >> 3;
blk[4] = (t10 + 4) >> 3;
blk[5] = (t11 + 4) >> 3;
blk[6] = (t12 + 4) >> 3;
blk[7] = (t13 + 4) >> 3;
}
static void hqx_idct_put(uint16_t *dst, ptrdiff_t stride,
int16_t *block, const uint8_t *quant)
{
int i, j;
for (i = 0; i < 8; i++)
idct_col(block + i, quant + i);
for (i = 0; i < 8; i++)
idct_row(block + i * 8);
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
int v = av_clip_uintp2(block[j + i * 8] + 0x800, 12);
dst[j] = (v << 4) | (v >> 8);
}
dst += stride >> 1;
}
}
av_cold void ff_hqxdsp_init(HQXDSPContext *c)
{
c->idct_put = hqx_idct_put;
}