gstreamer/gst/videoscale/vs_scanline.c

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/*
* Image Scaling Functions
* Copyright (c) 2005 David A. Schleef <ds@schleef.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "vs_scanline.h"
#include <liboil/liboil.h>
/* greyscale, i.e., single componenet */
void
vs_scanline_downsample_Y (uint8_t * dest, uint8_t * src, int n)
{
int i;
for (i = 0; i < n; i++) {
dest[i] = (src[i * 2] + src[i * 2 + 1]) / 2;
}
}
void
vs_scanline_resample_nearest_Y (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
dest[i] = (x < 32768 || j + 1 >= src_width) ? src[j] : src[j + 1];
acc += increment;
}
*accumulator = acc;
}
#include <glib.h>
void
vs_scanline_resample_linear_Y (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (j + 1 < src_width)
dest[i] = (src[j] * (65536 - x) + src[j + 1] * x) >> 16;
else
dest[i] = src[j];
acc += increment;
}
*accumulator = acc;
}
void
vs_scanline_merge_linear_Y (uint8_t * dest, uint8_t * src1, uint8_t * src2,
int n, int x)
{
uint32_t value = x >> 8;
oil_merge_linear_u8 (dest, src1, src2, &value, n);
}
void
vs_scanline_downsample_Y16 (uint8_t * dest, uint8_t * src, int n)
{
int i;
uint16_t *d = (uint16_t *) dest, *s = (uint16_t *) src;
for (i = 0; i < n; i++) {
d[i] = (s[i * 2] + s[i * 2 + 1]) / 2;
}
}
void
vs_scanline_resample_nearest_Y16 (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
uint16_t *d = (uint16_t *) dest, *s = (uint16_t *) src;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
d[i] = (x < 32768 || j + 1 >= src_width) ? s[j] : s[j + 1];
acc += increment;
}
*accumulator = acc;
}
#include <glib.h>
void
vs_scanline_resample_linear_Y16 (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
uint16_t *d = (uint16_t *) dest, *s = (uint16_t *) src;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (j + 1 < src_width)
d[i] = (s[j] * (65536 - x) + s[j + 1] * x) >> 16;
else
d[i] = s[j];
acc += increment;
}
*accumulator = acc;
}
void
vs_scanline_merge_linear_Y16 (uint8_t * dest, uint8_t * src1, uint8_t * src2,
int n, int x)
{
int i;
uint16_t *d = (uint16_t *) dest, *s1 = (uint16_t *) src1, *s2 =
(uint16_t *) src2;
for (i = 0; i < n; i++) {
d[i] = (s1[i] * (65536 - x) + s2[i] * x) >> 16;
}
}
/* RGBA */
void
vs_scanline_downsample_RGBA (uint8_t * dest, uint8_t * src, int n)
{
int i;
for (i = 0; i < n; i++) {
dest[i * 4 + 0] = (src[i * 8 + 0] + src[i * 8 + 4]) / 2;
dest[i * 4 + 1] = (src[i * 8 + 1] + src[i * 8 + 5]) / 2;
dest[i * 4 + 2] = (src[i * 8 + 2] + src[i * 8 + 6]) / 2;
dest[i * 4 + 3] = (src[i * 8 + 3] + src[i * 8 + 7]) / 2;
}
}
void
vs_scanline_resample_nearest_RGBA (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (j + 1 < src_width) {
dest[i * 4 + 0] = (x < 32768) ? src[j * 4 + 0] : src[j * 4 + 4];
dest[i * 4 + 1] = (x < 32768) ? src[j * 4 + 1] : src[j * 4 + 5];
dest[i * 4 + 2] = (x < 32768) ? src[j * 4 + 2] : src[j * 4 + 6];
dest[i * 4 + 3] = (x < 32768) ? src[j * 4 + 3] : src[j * 4 + 7];
} else {
dest[i * 4 + 0] = src[j * 4 + 0];
dest[i * 4 + 1] = src[j * 4 + 1];
dest[i * 4 + 2] = src[j * 4 + 2];
dest[i * 4 + 3] = src[j * 4 + 3];
}
acc += increment;
}
*accumulator = acc;
}
#include <stdio.h>
void
vs_scanline_resample_linear_RGBA (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
uint32_t vals[2];
vals[0] = *accumulator;
vals[1] = increment;
if (src_width % 2 == 0) {
oil_resample_linear_argb ((uint32_t *) dest, (uint32_t *) src, n, vals);
} else if (src_width > 1) {
if (n > 1)
oil_resample_linear_argb ((uint32_t *) dest, (uint32_t *) src, n - 1,
vals);
dest[4 * (n - 1) + 0] = src[(vals[0] >> 16) + 0];
dest[4 * (n - 1) + 1] = src[(vals[0] >> 16) + 1];
dest[4 * (n - 1) + 2] = src[(vals[0] >> 16) + 2];
dest[4 * (n - 1) + 3] = src[(vals[0] >> 16) + 3];
vals[0] += increment;
} else {
int i;
for (i = 0; i < n; i++) {
dest[4 * i + 0] = src[0];
dest[4 * i + 1] = src[1];
dest[4 * i + 2] = src[2];
dest[4 * i + 3] = src[3];
vals[0] += increment;
}
}
*accumulator = vals[0];
}
void
vs_scanline_merge_linear_RGBA (uint8_t * dest, uint8_t * src1, uint8_t * src2,
int n, int x)
{
uint32_t value = x >> 8;
oil_merge_linear_argb ((uint32_t *) dest, (uint32_t *) src1,
(uint32_t *) src2, &value, n);
}
/* RGB */
void
vs_scanline_downsample_RGB (uint8_t * dest, uint8_t * src, int n)
{
int i;
for (i = 0; i < n; i++) {
dest[i * 3 + 0] = (src[i * 6 + 0] + src[i * 6 + 3]) / 2;
dest[i * 3 + 1] = (src[i * 6 + 1] + src[i * 6 + 4]) / 2;
dest[i * 3 + 2] = (src[i * 6 + 2] + src[i * 6 + 5]) / 2;
}
}
void
vs_scanline_resample_nearest_RGB (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
dest[i * 3 + 0] = (x < 32768
|| j + 1 >= src_width) ? src[j * 3 + 0] : src[j * 3 + 3];
dest[i * 3 + 1] = (x < 32768
|| j + 1 >= src_width) ? src[j * 3 + 1] : src[j * 3 + 4];
dest[i * 3 + 2] = (x < 32768
|| j + 1 >= src_width) ? src[j * 3 + 2] : src[j * 3 + 5];
acc += increment;
}
*accumulator = acc;
}
void
vs_scanline_resample_linear_RGB (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (j + 1 < src_width) {
dest[i * 3 + 0] =
(src[j * 3 + 0] * (65536 - x) + src[j * 3 + 3] * x) >> 16;
dest[i * 3 + 1] =
(src[j * 3 + 1] * (65536 - x) + src[j * 3 + 4] * x) >> 16;
dest[i * 3 + 2] =
(src[j * 3 + 2] * (65536 - x) + src[j * 3 + 5] * x) >> 16;
} else {
dest[i * 3 + 0] = src[j * 3 + 0];
dest[i * 3 + 1] = src[j * 3 + 1];
dest[i * 3 + 2] = src[j * 3 + 2];
}
acc += increment;
}
*accumulator = acc;
}
void
vs_scanline_merge_linear_RGB (uint8_t * dest, uint8_t * src1, uint8_t * src2,
int n, int x)
{
uint32_t value = x >> 8;
oil_merge_linear_u8 (dest, src1, src2, &value, n * 3);
}
/* YUYV */
/* n is the number of pixels */
/* increment is per Y pixel */
void
vs_scanline_downsample_YUYV (uint8_t * dest, uint8_t * src, int n)
{
int i;
for (i = 0; i < n; i++) {
dest[i * 4 + 0] = (src[i * 8 + 0] + src[i * 8 + 2]) / 2;
dest[i * 4 + 1] = (src[i * 8 + 1] + src[i * 8 + 5]) / 2;
dest[i * 4 + 2] = (src[i * 8 + 4] + src[i * 8 + 6]) / 2;
dest[i * 4 + 3] = (src[i * 8 + 3] + src[i * 8 + 7]) / 2;
}
}
void
vs_scanline_resample_nearest_YUYV (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
int quads = (n + 1) / 2;
for (i = 0; i < quads; i++) {
j = acc >> 16;
x = acc & 0xffff;
dest[i * 4 + 0] = (x < 32768
|| j + 1 >= src_width) ? src[j * 2 + 0] : src[j * 2 + 2];
j = acc >> 17;
x = acc & 0x1ffff;
dest[i * 4 + 1] = (x < 65536
|| 2 * j + 2 >= src_width) ? src[j * 4 + 1] : src[j * 4 + 5];
if (2 * i + 1 < n && 2 * j + 1 < src_width)
dest[i * 4 + 3] = (x < 65536
|| 2 * j + 3 >= src_width) ? src[j * 4 + 3] : src[j * 4 + 7];
acc += increment;
j = acc >> 16;
x = acc & 0xffff;
if (2 * i + 1 < n && j < src_width) {
dest[i * 4 + 2] = (x < 32768
|| j + 1 >= src_width) ? src[j * 2 + 0] : src[j * 2 + 2];
acc += increment;
}
}
*accumulator = acc;
}
void
vs_scanline_resample_linear_YUYV (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
int quads = (n + 1) / 2;
for (i = 0; i < quads; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (j + 1 < src_width)
dest[i * 4 + 0] =
(src[j * 2 + 0] * (65536 - x) + src[j * 2 + 2] * x) >> 16;
else
dest[i * 4 + 0] = src[j * 2 + 0];
j = acc >> 17;
x = acc & 0x1ffff;
if (2 * j + 2 < src_width)
dest[i * 4 + 1] =
(src[j * 4 + 1] * (131072 - x) + src[j * 4 + 5] * x) >> 17;
else
dest[i * 4 + 1] = src[j * 4 + 1];
if (2 * i + 1 < n && 2 * j + 1 < src_width) {
if (2 * j + 3 < src_width)
dest[i * 4 + 3] =
(src[j * 4 + 3] * (131072 - x) + src[j * 4 + 7] * x) >> 17;
else
dest[i * 4 + 3] = src[j * 4 + 3];
}
acc += increment;
j = acc >> 16;
x = acc & 0xffff;
if (2 * i + 1 < n && j < src_width) {
if (j + 1 < src_width)
dest[i * 4 + 2] =
(src[j * 2 + 0] * (65536 - x) + src[j * 2 + 2] * x) >> 16;
else
dest[i * 4 + 2] = src[j * 2 + 0];
acc += increment;
}
}
*accumulator = acc;
}
void
vs_scanline_merge_linear_YUYV (uint8_t * dest, uint8_t * src1, uint8_t * src2,
int n, int x)
{
int i;
int quads = (n + 1) / 2;
for (i = 0; i < quads; i++) {
dest[i * 4 + 0] =
(src1[i * 4 + 0] * (65536 - x) + src2[i * 4 + 0] * x) >> 16;
dest[i * 4 + 1] =
(src1[i * 4 + 1] * (65536 - x) + src2[i * 4 + 1] * x) >> 16;
if (2 * i + 1 < n) {
dest[i * 4 + 2] =
(src1[i * 4 + 2] * (65536 - x) + src2[i * 4 + 2] * x) >> 16;
dest[i * 4 + 3] =
(src1[i * 4 + 3] * (65536 - x) + src2[i * 4 + 3] * x) >> 16;
}
}
}
/* UYVY */
/* n is the number of bi-pixels */
/* increment is per Y pixel */
void
vs_scanline_downsample_UYVY (uint8_t * dest, uint8_t * src, int n)
{
int i;
for (i = 0; i < n; i++) {
dest[i * 4 + 0] = (src[i * 8 + 0] + src[i * 8 + 4]) / 2;
dest[i * 4 + 1] = (src[i * 8 + 1] + src[i * 8 + 3]) / 2;
dest[i * 4 + 2] = (src[i * 8 + 2] + src[i * 8 + 6]) / 2;
dest[i * 4 + 3] = (src[i * 8 + 5] + src[i * 8 + 7]) / 2;
}
}
void
vs_scanline_resample_nearest_UYVY (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
int quads = (n + 1) / 2;
for (i = 0; i < quads; i++) {
j = acc >> 16;
x = acc & 0xffff;
dest[i * 4 + 1] = (x < 32768
|| j + 1 >= src_width) ? src[j * 2 + 1] : src[j * 2 + 3];
j = acc >> 17;
x = acc & 0x1ffff;
dest[i * 4 + 0] = (x < 65536
|| 2 * j + 2 >= src_width) ? src[j * 4 + 0] : src[j * 4 + 4];
if (2 * i + 1 < n && 2 * j + 1 < src_width)
dest[i * 4 + 2] = (x < 65536
|| 2 * j + 3 >= src_width) ? src[j * 4 + 2] : src[j * 4 + 6];
acc += increment;
j = acc >> 16;
x = acc & 0xffff;
if (2 * i + 1 < n && j < src_width) {
dest[i * 4 + 3] = (x < 32768
|| j + 1 >= src_width) ? src[j * 2 + 1] : src[j * 2 + 3];
acc += increment;
}
}
*accumulator = acc;
}
void
vs_scanline_resample_linear_UYVY (uint8_t * dest, uint8_t * src, int src_width,
int n, int *accumulator, int increment)
{
int acc = *accumulator;
int i;
int j;
int x;
int quads = (n + 1) / 2;
for (i = 0; i < quads; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (j + 1 < src_width)
dest[i * 4 + 1] =
(src[j * 2 + 1] * (65536 - x) + src[j * 2 + 3] * x) >> 16;
else
dest[i * 4 + 1] = src[j * 2 + 1];
j = acc >> 17;
x = acc & 0x1ffff;
if (2 * j + 2 < src_width)
dest[i * 4 + 0] =
(src[j * 4 + 0] * (131072 - x) + src[j * 4 + 4] * x) >> 17;
else
dest[i * 4 + 0] = src[j * 4 + 0];
if (i * 2 + 1 < n && 2 * j + 1 < src_width) {
if (2 * j + 3 < src_width)
dest[i * 4 + 2] =
(src[j * 4 + 2] * (131072 - x) + src[j * 4 + 6] * x) >> 17;
else
dest[i * 4 + 2] = src[j * 4 + 2];
}
acc += increment;
j = acc >> 16;
x = acc & 0xffff;
if (2 * i + 1 < n && j < src_width) {
if (j + 1 < src_width)
dest[i * 4 + 3] =
(src[j * 2 + 1] * (65536 - x) + src[j * 2 + 3] * x) >> 16;
else
dest[i * 4 + 3] = src[j * 2 + 1];
acc += increment;
}
}
*accumulator = acc;
}
void
vs_scanline_merge_linear_UYVY (uint8_t * dest, uint8_t * src1,
uint8_t * src2, int n, int x)
{
int i;
int quads = (n + 1) / 2;
for (i = 0; i < quads; i++) {
dest[i * 4 + 0] =
(src1[i * 4 + 0] * (65536 - x) + src2[i * 4 + 0] * x) >> 16;
dest[i * 4 + 1] =
(src1[i * 4 + 1] * (65536 - x) + src2[i * 4 + 1] * x) >> 16;
if (2 * i + 1 < n) {
dest[i * 4 + 2] =
(src1[i * 4 + 2] * (65536 - x) + src2[i * 4 + 2] * x) >> 16;
dest[i * 4 + 3] =
(src1[i * 4 + 3] * (65536 - x) + src2[i * 4 + 3] * x) >> 16;
}
}
}
/* RGB565 */
/* note that src and dest are uint16_t, and thus endian dependent */
#define RGB565_R(x) (((x)&0xf800)>>8 | ((x)&0xf800)>>13)
#define RGB565_G(x) (((x)&0x07e0)>>3 | ((x)&0x07e0)>>9)
#define RGB565_B(x) (((x)&0x001f)<<3 | ((x)&0x001f)>>2)
#define RGB565(r,g,b) \
((((r)<<8)&0xf800) | (((g)<<3)&0x07e0) | (((b)>>3)&0x001f))
void
vs_scanline_downsample_RGB565 (uint8_t * dest_u8, uint8_t * src_u8, int n)
{
uint16_t *dest = (uint16_t *) dest_u8;
uint16_t *src = (uint16_t *) src_u8;
int i;
for (i = 0; i < n; i++) {
dest[i] = RGB565 (
(RGB565_R (src[i * 2]) + RGB565_R (src[i * 2 + 1])) / 2,
(RGB565_G (src[i * 2]) + RGB565_G (src[i * 2 + 1])) / 2,
(RGB565_B (src[i * 2]) + RGB565_B (src[i * 2 + 1])) / 2);
}
}
void
vs_scanline_resample_nearest_RGB565 (uint8_t * dest_u8, uint8_t * src_u8,
int src_width, int n, int *accumulator, int increment)
{
uint16_t *dest = (uint16_t *) dest_u8;
uint16_t *src = (uint16_t *) src_u8;
int acc = *accumulator;
int i;
int j;
int x;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
dest[i] = (x < 32768 || j + 1 >= src_width) ? src[j] : src[j + 1];
acc += increment;
}
*accumulator = acc;
}
void
vs_scanline_resample_linear_RGB565 (uint8_t * dest_u8, uint8_t * src_u8,
int src_width, int n, int *accumulator, int increment)
{
uint16_t *dest = (uint16_t *) dest_u8;
uint16_t *src = (uint16_t *) src_u8;
int acc = *accumulator;
int i;
int j;
int x;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (j + 1 < src_width) {
dest[i] = RGB565 (
(RGB565_R (src[j]) * (65536 - x) + RGB565_R (src[j + 1]) * x) >> 16,
(RGB565_G (src[j]) * (65536 - x) + RGB565_G (src[j + 1]) * x) >> 16,
(RGB565_B (src[j]) * (65536 - x) + RGB565_B (src[j + 1]) * x) >> 16);
} else {
dest[i] = RGB565 (RGB565_R (src[j]),
RGB565_G (src[j]), RGB565_B (src[j]));
}
acc += increment;
}
*accumulator = acc;
}
void
vs_scanline_merge_linear_RGB565 (uint8_t * dest_u8, uint8_t * src1_u8,
uint8_t * src2_u8, int n, int x)
{
uint16_t *dest = (uint16_t *) dest_u8;
uint16_t *src1 = (uint16_t *) src1_u8;
uint16_t *src2 = (uint16_t *) src2_u8;
int i;
for (i = 0; i < n; i++) {
dest[i] = RGB565 (
(RGB565_R (src1[i]) * (65536 - x) + RGB565_R (src2[i]) * x) >> 16,
(RGB565_G (src1[i]) * (65536 - x) + RGB565_G (src2[i]) * x) >> 16,
(RGB565_B (src1[i]) * (65536 - x) + RGB565_B (src2[i]) * x) >> 16);
}
}
/* RGB555 */
/* note that src and dest are uint16_t, and thus endian dependent */
#define RGB555_R(x) (((x)&0x7c00)>>8 | ((x)&0x7c00)>>13)
#define RGB555_G(x) (((x)&0x03e0)>>3 | ((x)&0x03e0)>>9)
#define RGB555_B(x) (((x)&0x001f)<<3 | ((x)&0x001f)>>2)
#define RGB555(r,g,b) \
((((r)<<7)&0x7c00) | (((g)<<3)&0x03e0) | (((b)>>3)&0x001f))
void
vs_scanline_downsample_RGB555 (uint8_t * dest_u8, uint8_t * src_u8, int n)
{
uint16_t *dest = (uint16_t *) dest_u8;
uint16_t *src = (uint16_t *) src_u8;
int i;
for (i = 0; i < n; i++) {
dest[i] = RGB555 (
(RGB555_R (src[i * 2]) + RGB555_R (src[i * 2 + 1])) / 2,
(RGB555_G (src[i * 2]) + RGB555_G (src[i * 2 + 1])) / 2,
(RGB555_B (src[i * 2]) + RGB555_B (src[i * 2 + 1])) / 2);
}
}
void
vs_scanline_resample_nearest_RGB555 (uint8_t * dest_u8, uint8_t * src_u8,
int src_width, int n, int *accumulator, int increment)
{
uint16_t *dest = (uint16_t *) dest_u8;
uint16_t *src = (uint16_t *) src_u8;
int acc = *accumulator;
int i;
int j;
int x;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
dest[i] = (x < 32768 || j + 1 >= src_width) ? src[j] : src[j + 1];
acc += increment;
}
*accumulator = acc;
}
void
vs_scanline_resample_linear_RGB555 (uint8_t * dest_u8, uint8_t * src_u8,
int src_width, int n, int *accumulator, int increment)
{
uint16_t *dest = (uint16_t *) dest_u8;
uint16_t *src = (uint16_t *) src_u8;
int acc = *accumulator;
int i;
int j;
int x;
for (i = 0; i < n; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (j + 1 < src_width) {
dest[i] = RGB555 (
(RGB555_R (src[j]) * (65536 - x) + RGB555_R (src[j + 1]) * x) >> 16,
(RGB555_G (src[j]) * (65536 - x) + RGB555_G (src[j + 1]) * x) >> 16,
(RGB555_B (src[j]) * (65536 - x) + RGB555_B (src[j + 1]) * x) >> 16);
} else {
dest[i] = RGB555 (RGB555_R (src[j]),
RGB555_G (src[j]), RGB555_B (src[j]));
}
acc += increment;
}
*accumulator = acc;
}
void
vs_scanline_merge_linear_RGB555 (uint8_t * dest_u8, uint8_t * src1_u8,
uint8_t * src2_u8, int n, int x)
{
uint16_t *dest = (uint16_t *) dest_u8;
uint16_t *src1 = (uint16_t *) src1_u8;
uint16_t *src2 = (uint16_t *) src2_u8;
int i;
for (i = 0; i < n; i++) {
dest[i] = RGB555 (
(RGB555_R (src1[i]) * (65536 - x) + RGB555_R (src2[i]) * x) >> 16,
(RGB555_G (src1[i]) * (65536 - x) + RGB555_G (src2[i]) * x) >> 16,
(RGB555_B (src1[i]) * (65536 - x) + RGB555_B (src2[i]) * x) >> 16);
}
}