317 lines
12 KiB
C
317 lines
12 KiB
C
/* bitmap_scale.c - Bitmap scaling. */
|
|
/*
|
|
* GRUB -- GRand Unified Bootloader
|
|
* Copyright (C) 2006,2007,2008,2009 Free Software Foundation, Inc.
|
|
*
|
|
* GRUB is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* GRUB 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <grub/mm.h>
|
|
#include <grub/misc.h>
|
|
#include <grub/video.h>
|
|
#include <grub/bitmap.h>
|
|
#include <grub/bitmap_scale.h>
|
|
#include <grub/types.h>
|
|
#include <grub/dl.h>
|
|
|
|
GRUB_MOD_LICENSE ("GPLv3+");
|
|
|
|
/* Prototypes for module-local functions. */
|
|
static grub_err_t scale_nn (struct grub_video_bitmap *dst,
|
|
struct grub_video_bitmap *src);
|
|
static grub_err_t scale_bilinear (struct grub_video_bitmap *dst,
|
|
struct grub_video_bitmap *src);
|
|
|
|
/* This function creates a new scaled version of the bitmap SRC. The new
|
|
bitmap has dimensions DST_WIDTH by DST_HEIGHT. The scaling algorithm
|
|
is given by SCALE_METHOD. If an error is encountered, the return code is
|
|
not equal to GRUB_ERR_NONE, and the bitmap DST is either not created, or
|
|
it is destroyed before this function returns.
|
|
|
|
Supports only direct color modes which have components separated
|
|
into bytes (e.g., RGBA 8:8:8:8 or BGR 8:8:8 true color).
|
|
But because of this simplifying assumption, the implementation is
|
|
greatly simplified. */
|
|
grub_err_t
|
|
grub_video_bitmap_create_scaled (struct grub_video_bitmap **dst,
|
|
int dst_width, int dst_height,
|
|
struct grub_video_bitmap *src,
|
|
enum grub_video_bitmap_scale_method
|
|
scale_method)
|
|
{
|
|
*dst = 0;
|
|
|
|
/* Verify the simplifying assumptions. */
|
|
if (src == 0)
|
|
return grub_error (GRUB_ERR_BUG,
|
|
"null src bitmap in grub_video_bitmap_create_scaled");
|
|
if (src->mode_info.red_field_pos % 8 != 0
|
|
|| src->mode_info.green_field_pos % 8 != 0
|
|
|| src->mode_info.blue_field_pos % 8 != 0
|
|
|| src->mode_info.reserved_field_pos % 8 != 0)
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
|
|
"src format not supported for scale");
|
|
if (src->mode_info.width == 0 || src->mode_info.height == 0)
|
|
return grub_error (GRUB_ERR_BAD_ARGUMENT,
|
|
"source bitmap has a zero dimension");
|
|
if (dst_width <= 0 || dst_height <= 0)
|
|
return grub_error (GRUB_ERR_BUG,
|
|
"requested to scale to a size w/ a zero dimension");
|
|
if (src->mode_info.bytes_per_pixel * 8 != src->mode_info.bpp)
|
|
return grub_error (GRUB_ERR_BUG,
|
|
"bitmap to scale has inconsistent Bpp and bpp");
|
|
|
|
/* Create the new bitmap. */
|
|
grub_err_t ret;
|
|
ret = grub_video_bitmap_create (dst, dst_width, dst_height,
|
|
src->mode_info.blit_format);
|
|
if (ret != GRUB_ERR_NONE)
|
|
return ret; /* Error. */
|
|
|
|
switch (scale_method)
|
|
{
|
|
case GRUB_VIDEO_BITMAP_SCALE_METHOD_FASTEST:
|
|
case GRUB_VIDEO_BITMAP_SCALE_METHOD_NEAREST:
|
|
ret = scale_nn (*dst, src);
|
|
break;
|
|
case GRUB_VIDEO_BITMAP_SCALE_METHOD_BEST:
|
|
case GRUB_VIDEO_BITMAP_SCALE_METHOD_BILINEAR:
|
|
ret = scale_bilinear (*dst, src);
|
|
break;
|
|
default:
|
|
ret = grub_error (GRUB_ERR_BUG, "Invalid scale_method value");
|
|
break;
|
|
}
|
|
|
|
if (ret == GRUB_ERR_NONE)
|
|
{
|
|
/* Success: *dst is now a pointer to the scaled bitmap. */
|
|
return GRUB_ERR_NONE;
|
|
}
|
|
else
|
|
{
|
|
/* Destroy the bitmap and return the error code. */
|
|
grub_video_bitmap_destroy (*dst);
|
|
*dst = 0;
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/* Nearest neighbor bitmap scaling algorithm.
|
|
|
|
Copy the bitmap SRC to the bitmap DST, scaling the bitmap to fit the
|
|
dimensions of DST. This function uses the nearest neighbor algorithm to
|
|
interpolate the pixels.
|
|
|
|
Supports only direct color modes which have components separated
|
|
into bytes (e.g., RGBA 8:8:8:8 or BGR 8:8:8 true color).
|
|
But because of this simplifying assumption, the implementation is
|
|
greatly simplified. */
|
|
static grub_err_t
|
|
scale_nn (struct grub_video_bitmap *dst, struct grub_video_bitmap *src)
|
|
{
|
|
/* Verify the simplifying assumptions. */
|
|
if (dst == 0 || src == 0)
|
|
return grub_error (GRUB_ERR_BUG, "null bitmap in scale_nn");
|
|
if (dst->mode_info.red_field_pos % 8 != 0
|
|
|| dst->mode_info.green_field_pos % 8 != 0
|
|
|| dst->mode_info.blue_field_pos % 8 != 0
|
|
|| dst->mode_info.reserved_field_pos % 8 != 0)
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
|
|
"dst format not supported");
|
|
if (src->mode_info.red_field_pos % 8 != 0
|
|
|| src->mode_info.green_field_pos % 8 != 0
|
|
|| src->mode_info.blue_field_pos % 8 != 0
|
|
|| src->mode_info.reserved_field_pos % 8 != 0)
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
|
|
"src format not supported");
|
|
if (dst->mode_info.red_field_pos != src->mode_info.red_field_pos
|
|
|| dst->mode_info.red_mask_size != src->mode_info.red_mask_size
|
|
|| dst->mode_info.green_field_pos != src->mode_info.green_field_pos
|
|
|| dst->mode_info.green_mask_size != src->mode_info.green_mask_size
|
|
|| dst->mode_info.blue_field_pos != src->mode_info.blue_field_pos
|
|
|| dst->mode_info.blue_mask_size != src->mode_info.blue_mask_size
|
|
|| dst->mode_info.reserved_field_pos !=
|
|
src->mode_info.reserved_field_pos
|
|
|| dst->mode_info.reserved_mask_size !=
|
|
src->mode_info.reserved_mask_size)
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
|
|
"dst and src not compatible");
|
|
if (dst->mode_info.bytes_per_pixel != src->mode_info.bytes_per_pixel)
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
|
|
"dst and src not compatible");
|
|
if (dst->mode_info.width == 0 || dst->mode_info.height == 0
|
|
|| src->mode_info.width == 0 || src->mode_info.height == 0)
|
|
return grub_error (GRUB_ERR_BUG, "bitmap has a zero dimension");
|
|
|
|
grub_uint8_t *ddata = dst->data;
|
|
grub_uint8_t *sdata = src->data;
|
|
int dw = dst->mode_info.width;
|
|
int dh = dst->mode_info.height;
|
|
int sw = src->mode_info.width;
|
|
int sh = src->mode_info.height;
|
|
int dstride = dst->mode_info.pitch;
|
|
int sstride = src->mode_info.pitch;
|
|
/* bytes_per_pixel is the same for both src and dst. */
|
|
int bytes_per_pixel = dst->mode_info.bytes_per_pixel;
|
|
|
|
int dy;
|
|
for (dy = 0; dy < dh; dy++)
|
|
{
|
|
int dx;
|
|
for (dx = 0; dx < dw; dx++)
|
|
{
|
|
grub_uint8_t *dptr;
|
|
grub_uint8_t *sptr;
|
|
int sx;
|
|
int sy;
|
|
int comp;
|
|
|
|
/* Compute the source coordinate that the destination coordinate
|
|
maps to. Note: sx/sw = dx/dw => sx = sw*dx/dw. */
|
|
sx = sw * dx / dw;
|
|
sy = sh * dy / dh;
|
|
|
|
/* Get the address of the pixels in src and dst. */
|
|
dptr = ddata + dy * dstride + dx * bytes_per_pixel;
|
|
sptr = sdata + sy * sstride + sx * bytes_per_pixel;
|
|
|
|
/* Copy the pixel color value. */
|
|
for (comp = 0; comp < bytes_per_pixel; comp++)
|
|
dptr[comp] = sptr[comp];
|
|
}
|
|
}
|
|
return GRUB_ERR_NONE;
|
|
}
|
|
|
|
/* Bilinear interpolation image scaling algorithm.
|
|
|
|
Copy the bitmap SRC to the bitmap DST, scaling the bitmap to fit the
|
|
dimensions of DST. This function uses the bilinear interpolation algorithm
|
|
to interpolate the pixels.
|
|
|
|
Supports only direct color modes which have components separated
|
|
into bytes (e.g., RGBA 8:8:8:8 or BGR 8:8:8 true color).
|
|
But because of this simplifying assumption, the implementation is
|
|
greatly simplified. */
|
|
static grub_err_t
|
|
scale_bilinear (struct grub_video_bitmap *dst, struct grub_video_bitmap *src)
|
|
{
|
|
/* Verify the simplifying assumptions. */
|
|
if (dst == 0 || src == 0)
|
|
return grub_error (GRUB_ERR_BUG, "null bitmap in scale func");
|
|
if (dst->mode_info.red_field_pos % 8 != 0
|
|
|| dst->mode_info.green_field_pos % 8 != 0
|
|
|| dst->mode_info.blue_field_pos % 8 != 0
|
|
|| dst->mode_info.reserved_field_pos % 8 != 0)
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "dst format not supported");
|
|
if (src->mode_info.red_field_pos % 8 != 0
|
|
|| src->mode_info.green_field_pos % 8 != 0
|
|
|| src->mode_info.blue_field_pos % 8 != 0
|
|
|| src->mode_info.reserved_field_pos % 8 != 0)
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "src format not supported");
|
|
if (dst->mode_info.red_field_pos != src->mode_info.red_field_pos
|
|
|| dst->mode_info.red_mask_size != src->mode_info.red_mask_size
|
|
|| dst->mode_info.green_field_pos != src->mode_info.green_field_pos
|
|
|| dst->mode_info.green_mask_size != src->mode_info.green_mask_size
|
|
|| dst->mode_info.blue_field_pos != src->mode_info.blue_field_pos
|
|
|| dst->mode_info.blue_mask_size != src->mode_info.blue_mask_size
|
|
|| dst->mode_info.reserved_field_pos !=
|
|
src->mode_info.reserved_field_pos
|
|
|| dst->mode_info.reserved_mask_size !=
|
|
src->mode_info.reserved_mask_size)
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "dst and src not compatible");
|
|
if (dst->mode_info.bytes_per_pixel != src->mode_info.bytes_per_pixel)
|
|
return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET, "dst and src not compatible");
|
|
if (dst->mode_info.width == 0 || dst->mode_info.height == 0
|
|
|| src->mode_info.width == 0 || src->mode_info.height == 0)
|
|
return grub_error (GRUB_ERR_BUG, "bitmap has a zero dimension");
|
|
|
|
grub_uint8_t *ddata = dst->data;
|
|
grub_uint8_t *sdata = src->data;
|
|
int dw = dst->mode_info.width;
|
|
int dh = dst->mode_info.height;
|
|
int sw = src->mode_info.width;
|
|
int sh = src->mode_info.height;
|
|
int dstride = dst->mode_info.pitch;
|
|
int sstride = src->mode_info.pitch;
|
|
/* bytes_per_pixel is the same for both src and dst. */
|
|
int bytes_per_pixel = dst->mode_info.bytes_per_pixel;
|
|
|
|
int dy;
|
|
for (dy = 0; dy < dh; dy++)
|
|
{
|
|
int dx;
|
|
for (dx = 0; dx < dw; dx++)
|
|
{
|
|
grub_uint8_t *dptr;
|
|
grub_uint8_t *sptr;
|
|
int sx;
|
|
int sy;
|
|
int comp;
|
|
|
|
/* Compute the source coordinate that the destination coordinate
|
|
maps to. Note: sx/sw = dx/dw => sx = sw*dx/dw. */
|
|
sx = sw * dx / dw;
|
|
sy = sh * dy / dh;
|
|
|
|
/* Get the address of the pixels in src and dst. */
|
|
dptr = ddata + dy * dstride + dx * bytes_per_pixel;
|
|
sptr = sdata + sy * sstride + sx * bytes_per_pixel;
|
|
|
|
/* If we have enough space to do so, use bilinear interpolation.
|
|
Otherwise, fall back to nearest neighbor for this pixel. */
|
|
if (sx < sw - 1 && sy < sh - 1)
|
|
{
|
|
/* Do bilinear interpolation. */
|
|
|
|
/* Fixed-point .8 numbers representing the fraction of the
|
|
distance in the x (u) and y (v) direction within the
|
|
box of 4 pixels in the source. */
|
|
int u = (256 * sw * dx / dw) - (sx * 256);
|
|
int v = (256 * sh * dy / dh) - (sy * 256);
|
|
|
|
for (comp = 0; comp < bytes_per_pixel; comp++)
|
|
{
|
|
/* Get the component's values for the
|
|
four source corner pixels. */
|
|
int f00 = sptr[comp];
|
|
int f10 = sptr[comp + bytes_per_pixel];
|
|
int f01 = sptr[comp + sstride];
|
|
int f11 = sptr[comp + sstride + bytes_per_pixel];
|
|
|
|
/* Count coeffecients. */
|
|
int c00 = (256 - u) * (256 - v);
|
|
int c10 = u * (256 - v);
|
|
int c01 = (256 - u) * v;
|
|
int c11 = u * v;
|
|
|
|
/* Interpolate. */
|
|
int fxy = c00 * f00 + c01 * f01 + c10 * f10 + c11 * f11;
|
|
fxy = fxy / (256 * 256);
|
|
|
|
dptr[comp] = fxy;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* Fall back to nearest neighbor interpolation. */
|
|
/* Copy the pixel color value. */
|
|
for (comp = 0; comp < bytes_per_pixel; comp++)
|
|
dptr[comp] = sptr[comp];
|
|
}
|
|
}
|
|
}
|
|
return GRUB_ERR_NONE;
|
|
}
|