gstreamer/gst/videoscale/vs_image.c
David Schleef 25d874ec9b gst/videoscale/: Add a 4-tap image scaler. Theoretically looks much prettier.
Original commit message from CVS:
* gst/videoscale/Makefile.am:
* gst/videoscale/gstvideoscale.c:
* gst/videoscale/gstvideoscale.h:
* gst/videoscale/vs_4tap.c:
* gst/videoscale/vs_4tap.h:
* gst/videoscale/vs_image.c:
* gst/videoscale/vs_image.h:
* gst/videoscale/vs_scanline.c:
* gst/videoscale/vs_scanline.h:
Add a 4-tap image scaler.  Theoretically looks much prettier.
The tap calculation could use some improvement.
2006-11-14 23:08:38 +00:00

853 lines
22 KiB
C

/*
* 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 <string.h>
#include "vs_scanline.h"
#include "vs_image.h"
#define ROUND_UP_2(x) (((x)+1)&~1)
#define ROUND_UP_4(x) (((x)+3)&~3)
#define ROUND_UP_8(x) (((x)+7)&~7)
void
vs_image_scale_nearest_RGBA (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
int i;
int j;
int x;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
acc = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
xacc = 0;
vs_scanline_resample_nearest_RGBA (dest->pixels + i * dest->stride,
src->pixels + j * src->stride, dest->width, &xacc, x_increment);
acc += y_increment;
}
}
void
vs_image_scale_linear_RGBA (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
uint8_t *tmp1;
uint8_t *tmp2;
int y1;
int y2;
int i;
int j;
int x;
int dest_size;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
dest_size = dest->width * 4;
tmp1 = tmpbuf;
tmp2 = tmpbuf + dest_size;
acc = 0;
xacc = 0;
y2 = -1;
vs_scanline_resample_linear_RGBA (tmp1, src->pixels, dest->width, &xacc,
x_increment);
y1 = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (x == 0) {
if (j == y1) {
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
} else if (j == y2) {
memcpy (dest->pixels + i * dest->stride, tmp2, dest_size);
} else {
xacc = 0;
vs_scanline_resample_linear_RGBA (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
}
} else {
if (j == y1) {
if (j + 1 != y2) {
xacc = 0;
vs_scanline_resample_linear_RGBA (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = j + 1;
}
vs_scanline_merge_linear_RGBA (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
} else if (j == y2) {
if (j + 1 != y1) {
xacc = 0;
vs_scanline_resample_linear_RGBA (tmp1,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y1 = j + 1;
}
vs_scanline_merge_linear_RGBA (dest->pixels + i * dest->stride,
tmp2, tmp1, dest->width, x);
} else {
xacc = 0;
vs_scanline_resample_linear_RGBA (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
xacc = 0;
vs_scanline_resample_linear_RGBA (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = (j + 1);
vs_scanline_merge_linear_RGBA (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
}
}
acc += y_increment;
}
}
void
vs_image_scale_nearest_RGB (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
int i;
int j;
int x;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
acc = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
xacc = 0;
vs_scanline_resample_nearest_RGB (dest->pixels + i * dest->stride,
src->pixels + j * src->stride, dest->width, &xacc, x_increment);
acc += y_increment;
}
}
void
vs_image_scale_linear_RGB (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
uint8_t *tmp1;
uint8_t *tmp2;
int y1;
int y2;
int i;
int j;
int x;
int dest_size;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
dest_size = dest->width * 3;
tmp1 = tmpbuf;
tmp2 = tmpbuf + dest_size;
acc = 0;
xacc = 0;
y2 = -1;
vs_scanline_resample_linear_RGB (tmp1, src->pixels, dest->width, &xacc,
x_increment);
y1 = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (x == 0) {
if (j == y1) {
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
} else if (j == y2) {
memcpy (dest->pixels + i * dest->stride, tmp2, dest_size);
} else {
xacc = 0;
vs_scanline_resample_linear_RGB (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
}
} else {
if (j == y1) {
if (j + 1 != y2) {
xacc = 0;
vs_scanline_resample_linear_RGB (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = j + 1;
}
vs_scanline_merge_linear_RGB (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
} else if (j == y2) {
if (j + 1 != y1) {
xacc = 0;
vs_scanline_resample_linear_RGB (tmp1,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y1 = j + 1;
}
vs_scanline_merge_linear_RGB (dest->pixels + i * dest->stride,
tmp2, tmp1, dest->width, x);
} else {
xacc = 0;
vs_scanline_resample_linear_RGB (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
xacc = 0;
vs_scanline_resample_linear_RGB (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = (j + 1);
vs_scanline_merge_linear_RGB (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
}
}
acc += y_increment;
}
}
/* YUYV */
void
vs_image_scale_nearest_YUYV (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
int i;
int j;
int x;
int xacc;
int n_quads;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
n_quads = ROUND_UP_2 (dest->width) / 2;
acc = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
xacc = 0;
vs_scanline_resample_nearest_YUYV (dest->pixels + i * dest->stride,
src->pixels + j * src->stride, n_quads, &xacc, x_increment);
acc += y_increment;
}
}
void
vs_image_scale_linear_YUYV (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
uint8_t *tmp1;
uint8_t *tmp2;
int y1;
int y2;
int i;
int j;
int x;
int dest_size;
int n_quads;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
dest_size = ROUND_UP_4 (dest->width * 2);
n_quads = ROUND_UP_2 (dest->width) / 2;
tmp1 = tmpbuf;
tmp2 = tmpbuf + dest_size;
acc = 0;
xacc = 0;
y2 = -1;
vs_scanline_resample_linear_YUYV (tmp1, src->pixels, n_quads, &xacc,
x_increment);
y1 = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (x == 0) {
if (j == y1) {
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
} else if (j == y2) {
memcpy (dest->pixels + i * dest->stride, tmp2, dest_size);
} else {
xacc = 0;
vs_scanline_resample_linear_YUYV (tmp1, src->pixels + j * src->stride,
n_quads, &xacc, x_increment);
y1 = j;
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
}
} else {
if (j == y1) {
if (j + 1 != y2) {
xacc = 0;
vs_scanline_resample_linear_YUYV (tmp2,
src->pixels + (j + 1) * src->stride, n_quads, &xacc, x_increment);
y2 = j + 1;
}
vs_scanline_merge_linear_YUYV (dest->pixels + i * dest->stride,
tmp1, tmp2, n_quads, x);
} else if (j == y2) {
if (j + 1 != y1) {
xacc = 0;
vs_scanline_resample_linear_YUYV (tmp1,
src->pixels + (j + 1) * src->stride, n_quads, &xacc, x_increment);
y1 = j + 1;
}
vs_scanline_merge_linear_YUYV (dest->pixels + i * dest->stride,
tmp2, tmp1, n_quads, x);
} else {
xacc = 0;
vs_scanline_resample_linear_YUYV (tmp1, src->pixels + j * src->stride,
n_quads, &xacc, x_increment);
y1 = j;
xacc = 0;
vs_scanline_resample_linear_YUYV (tmp2,
src->pixels + (j + 1) * src->stride, n_quads, &xacc, x_increment);
y2 = (j + 1);
vs_scanline_merge_linear_YUYV (dest->pixels + i * dest->stride,
tmp1, tmp2, n_quads, x);
}
}
acc += y_increment;
}
}
/* UYVY */
void
vs_image_scale_nearest_UYVY (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
int i;
int j;
int x;
int xacc;
int n_quads;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
n_quads = (dest->width + 1) / 2;
acc = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
xacc = 0;
vs_scanline_resample_nearest_UYVY (dest->pixels + i * dest->stride,
src->pixels + j * src->stride, n_quads, &xacc, x_increment);
acc += y_increment;
}
}
void
vs_image_scale_linear_UYVY (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
uint8_t *tmp1;
uint8_t *tmp2;
int y1;
int y2;
int i;
int j;
int x;
int dest_size;
int n_quads;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
dest_size = ROUND_UP_4 (dest->width * 2);
n_quads = ROUND_UP_2 (dest->width) / 2;
tmp1 = tmpbuf;
tmp2 = tmpbuf + dest_size;
acc = 0;
xacc = 0;
y2 = -1;
vs_scanline_resample_linear_UYVY (tmp1, src->pixels, n_quads, &xacc,
x_increment);
y1 = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (x == 0) {
if (j == y1) {
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
} else if (j == y2) {
memcpy (dest->pixels + i * dest->stride, tmp2, dest_size);
} else {
xacc = 0;
vs_scanline_resample_linear_UYVY (tmp1, src->pixels + j * src->stride,
n_quads, &xacc, x_increment);
y1 = j;
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
}
} else {
if (j == y1) {
if (j + 1 != y2) {
xacc = 0;
vs_scanline_resample_linear_UYVY (tmp2,
src->pixels + (j + 1) * src->stride, n_quads, &xacc, x_increment);
y2 = j + 1;
}
vs_scanline_merge_linear_UYVY (dest->pixels + i * dest->stride,
tmp1, tmp2, n_quads, x);
} else if (j == y2) {
if (j + 1 != y1) {
xacc = 0;
vs_scanline_resample_linear_UYVY (tmp1,
src->pixels + (j + 1) * src->stride, n_quads, &xacc, x_increment);
y1 = j + 1;
}
vs_scanline_merge_linear_UYVY (dest->pixels + i * dest->stride,
tmp2, tmp1, n_quads, x);
} else {
xacc = 0;
vs_scanline_resample_linear_UYVY (tmp1, src->pixels + j * src->stride,
n_quads, &xacc, x_increment);
y1 = j;
xacc = 0;
vs_scanline_resample_linear_UYVY (tmp2,
src->pixels + (j + 1) * src->stride, n_quads, &xacc, x_increment);
y2 = (j + 1);
vs_scanline_merge_linear_UYVY (dest->pixels + i * dest->stride,
tmp1, tmp2, n_quads, x);
}
}
acc += y_increment;
}
}
/* greyscale */
void
vs_image_scale_nearest_Y (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
int i;
int j;
int x;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
acc = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
xacc = 0;
vs_scanline_resample_nearest_Y (dest->pixels + i * dest->stride,
src->pixels + j * src->stride, dest->width, &xacc, x_increment);
acc += y_increment;
}
}
void
vs_image_scale_linear_Y (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
uint8_t *tmp1;
uint8_t *tmp2;
int y1;
int y2;
int i;
int j;
int x;
int dest_size;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
dest_size = dest->width;
tmp1 = tmpbuf;
tmp2 = tmpbuf + dest_size;
acc = 0;
xacc = 0;
y2 = -1;
vs_scanline_resample_linear_Y (tmp1, src->pixels, dest->width, &xacc,
x_increment);
y1 = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (x == 0) {
if (j == y1) {
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
} else if (j == y2) {
memcpy (dest->pixels + i * dest->stride, tmp2, dest_size);
} else {
xacc = 0;
vs_scanline_resample_linear_Y (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
}
} else {
if (j == y1) {
if (j + 1 != y2) {
xacc = 0;
vs_scanline_resample_linear_Y (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = j + 1;
}
vs_scanline_merge_linear_Y (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
} else if (j == y2) {
if (j + 1 != y1) {
xacc = 0;
vs_scanline_resample_linear_Y (tmp1,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y1 = j + 1;
}
vs_scanline_merge_linear_Y (dest->pixels + i * dest->stride,
tmp2, tmp1, dest->width, x);
} else {
xacc = 0;
vs_scanline_resample_linear_Y (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
xacc = 0;
vs_scanline_resample_linear_Y (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = (j + 1);
vs_scanline_merge_linear_Y (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
}
}
acc += y_increment;
}
}
/* RGB565 */
void
vs_image_scale_nearest_RGB565 (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
int i;
int j;
int x;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
acc = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
xacc = 0;
vs_scanline_resample_nearest_RGB565 (dest->pixels + i * dest->stride,
src->pixels + j * src->stride, dest->width, &xacc, x_increment);
acc += y_increment;
}
}
void
vs_image_scale_linear_RGB565 (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
uint8_t *tmp1;
uint8_t *tmp2;
int y1;
int y2;
int i;
int j;
int x;
int dest_size;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
dest_size = dest->width * 2;
tmp1 = tmpbuf;
tmp2 = tmpbuf + dest_size;
acc = 0;
xacc = 0;
y2 = -1;
vs_scanline_resample_linear_RGB565 (tmp1, src->pixels, dest->width, &xacc,
x_increment);
y1 = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (x == 0) {
if (j == y1) {
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
} else if (j == y2) {
memcpy (dest->pixels + i * dest->stride, tmp2, dest_size);
} else {
xacc = 0;
vs_scanline_resample_linear_RGB565 (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
}
} else {
if (j == y1) {
if (j + 1 != y2) {
xacc = 0;
vs_scanline_resample_linear_RGB565 (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = j + 1;
}
vs_scanline_merge_linear_RGB565 (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
} else if (j == y2) {
if (j + 1 != y1) {
xacc = 0;
vs_scanline_resample_linear_RGB565 (tmp1,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y1 = j + 1;
}
vs_scanline_merge_linear_RGB565 (dest->pixels + i * dest->stride,
tmp2, tmp1, dest->width, x);
} else {
xacc = 0;
vs_scanline_resample_linear_RGB565 (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
xacc = 0;
vs_scanline_resample_linear_RGB565 (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = (j + 1);
vs_scanline_merge_linear_RGB565 (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
}
}
acc += y_increment;
}
}
/* RGB555 */
void
vs_image_scale_nearest_RGB555 (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
int i;
int j;
int x;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
acc = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
xacc = 0;
vs_scanline_resample_nearest_RGB555 (dest->pixels + i * dest->stride,
src->pixels + j * src->stride, dest->width, &xacc, x_increment);
acc += y_increment;
}
}
void
vs_image_scale_linear_RGB555 (const VSImage * dest, const VSImage * src,
uint8_t * tmpbuf)
{
int acc;
int y_increment;
int x_increment;
uint8_t *tmp1;
uint8_t *tmp2;
int y1;
int y2;
int i;
int j;
int x;
int dest_size;
int xacc;
y_increment = ((src->height - 1) << 16) / (dest->height - 1);
x_increment = ((src->width - 1) << 16) / (dest->width - 1);
dest_size = dest->width * 2;
tmp1 = tmpbuf;
tmp2 = tmpbuf + dest_size;
acc = 0;
xacc = 0;
y2 = -1;
vs_scanline_resample_linear_RGB555 (tmp1, src->pixels, dest->width, &xacc,
x_increment);
y1 = 0;
for (i = 0; i < dest->height; i++) {
j = acc >> 16;
x = acc & 0xffff;
if (x == 0) {
if (j == y1) {
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
} else if (j == y2) {
memcpy (dest->pixels + i * dest->stride, tmp2, dest_size);
} else {
xacc = 0;
vs_scanline_resample_linear_RGB555 (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
memcpy (dest->pixels + i * dest->stride, tmp1, dest_size);
}
} else {
if (j == y1) {
if (j + 1 != y2) {
xacc = 0;
vs_scanline_resample_linear_RGB555 (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = j + 1;
}
vs_scanline_merge_linear_RGB555 (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
} else if (j == y2) {
if (j + 1 != y1) {
xacc = 0;
vs_scanline_resample_linear_RGB555 (tmp1,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y1 = j + 1;
}
vs_scanline_merge_linear_RGB555 (dest->pixels + i * dest->stride,
tmp2, tmp1, dest->width, x);
} else {
xacc = 0;
vs_scanline_resample_linear_RGB555 (tmp1, src->pixels + j * src->stride,
dest->width, &xacc, x_increment);
y1 = j;
xacc = 0;
vs_scanline_resample_linear_RGB555 (tmp2,
src->pixels + (j + 1) * src->stride, dest->width, &xacc,
x_increment);
y2 = (j + 1);
vs_scanline_merge_linear_RGB555 (dest->pixels + i * dest->stride,
tmp1, tmp2, dest->width, x);
}
}
acc += y_increment;
}
}