libavcodec/huffyuvdsp.c

   1 /*
   2  * This file is part of Libav.
   3  *
   4  * Libav is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * Libav is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with Libav; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #include <stdint.h>
  20
  21 #include "config.h"
  22 #include "libavutil/attributes.h"
  23 #include "mathops.h"
  24 #include "huffyuvdsp.h"
  25
  26 // 0x7f7f7f7f or 0x7f7f7f7f7f7f7f7f or whatever, depending on the cpu's native arithmetic size
  27 #define pb_7f (~0UL / 255 * 0x7f)
  28 #define pb_80 (~0UL / 255 * 0x80)
  29
  30 static void add_bytes_c(uint8_t *dst, uint8_t *src, int w)
  31 {
  32     long i;
  33
  34     for (i = 0; i <= w - (int) sizeof(long); i += sizeof(long)) {
  35         long a = *(long *) (src + i);
  36         long b = *(long *) (dst + i);
  37         *(long *) (dst + i) = ((a & pb_7f) + (b & pb_7f)) ^ ((a ^ b) & pb_80);
  38     }
  39     for (; i < w; i++)
  40         dst[i + 0] += src[i + 0];
  41 }
  42
  43 static void add_hfyu_median_pred_c(uint8_t *dst, const uint8_t *src1,
  44                                    const uint8_t *diff, int w,
  45                                    int *left, int *left_top)
  46 {
  47     int i;
  48     uint8_t l, lt;
  49
  50     l  = *left;
  51     lt = *left_top;
  52
  53     for (i = 0; i < w; i++) {
  54         l      = mid_pred(l, src1[i], (l + src1[i] - lt) & 0xFF) + diff[i];
  55         lt     = src1[i];
  56         dst[i] = l;
  57     }
  58
  59     *left     = l;
  60     *left_top = lt;
  61 }
  62
  63 static int add_hfyu_left_pred_c(uint8_t *dst, const uint8_t *src, int w,
  64                                 int acc)
  65 {
  66     int i;
  67
  68     for (i = 0; i < w - 1; i++) {
  69         acc   += src[i];
  70         dst[i] = acc;
  71         i++;
  72         acc   += src[i];
  73         dst[i] = acc;
  74     }
  75
  76     for (; i < w; i++) {
  77         acc   += src[i];
  78         dst[i] = acc;
  79     }
  80
  81     return acc;
  82 }
  83
  84 #if HAVE_BIGENDIAN
  85 #define B 3
  86 #define G 2
  87 #define R 1
  88 #define A 0
  89 #else
  90 #define B 0
  91 #define G 1
  92 #define R 2
  93 #define A 3
  94 #endif
  95 static void add_hfyu_left_pred_bgr32_c(uint8_t *dst, const uint8_t *src,
  96                                        int w, int *red, int *green,
  97                                        int *blue, int *alpha)
  98 {
  99     int i, r = *red, g = *green, b = *blue, a = *alpha;
 100
 101     for (i = 0; i < w; i++) {
 102         b += src[4 * i + B];
 103         g += src[4 * i + G];
 104         r += src[4 * i + R];
 105         a += src[4 * i + A];
 106
 107         dst[4 * i + B] = b;
 108         dst[4 * i + G] = g;
 109         dst[4 * i + R] = r;
 110         dst[4 * i + A] = a;
 111     }
 112
 113     *red   = r;
 114     *green = g;
 115     *blue  = b;
 116     *alpha = a;
 117 }
 118 #undef B
 119 #undef G
 120 #undef R
 121 #undef A
 122
 123 av_cold void ff_huffyuvdsp_init(HuffYUVDSPContext *c)
 124 {
 125     c->add_bytes                = add_bytes_c;
 126     c->add_hfyu_median_pred     = add_hfyu_median_pred_c;
 127     c->add_hfyu_left_pred       = add_hfyu_left_pred_c;
 128     c->add_hfyu_left_pred_bgr32 = add_hfyu_left_pred_bgr32_c;
 129
 130     if (ARCH_PPC)
 131         ff_huffyuvdsp_init_ppc(c);
 132     if (ARCH_X86)
 133         ff_huffyuvdsp_init_x86(c);
 134 }