gimp/plug-ins/common/autocrop.c

337 lines
7.4 KiB
C

/*
* Autocrop plug-in version 1.00
* by Tim Newsome <drz@froody.bloke.com>
* thanks to quartic for finding a nasty bug for me
*/
/* 1999/04/09 -- Sven Neumann <sven@gimp.org>
* Fixed bad crash that occured when running on an entirely blank image.
* Cleaned up the code a bit, while I was at it.
*/
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <libgimp/gimp.h>
#include "libgimp/stdplugins-intl.h"
/* Declare local functions. */
static void query (void);
static void run (gchar *name,
gint nparams,
GimpParam *param,
gint *nreturn_vals,
GimpParam **return_vals);
static gint colors_equal (guchar *col1,
guchar *col2,
gint bytes);
static gint guess_bgcolor (GimpPixelRgn *pr,
gint width,
gint height,
gint bytes,
guchar *color);
static void doit (GimpDrawable *drawable,
gint32 image_id,
gboolean show_progress);
GimpPlugInInfo PLUG_IN_INFO =
{
NULL, /* init_proc */
NULL, /* quit_proc */
query, /* query_proc */
run, /* run_proc */
};
static gint bytes;
MAIN ()
static void
query (void)
{
static GimpParamDef args[] =
{
{ GIMP_PDB_INT32, "run_mode", "Interactive, non-interactive" },
{ GIMP_PDB_IMAGE, "image", "Input image" },
{ GIMP_PDB_DRAWABLE, "drawable", "Input drawable" }
};
static gint nargs = sizeof (args) / sizeof (args[0]);
gimp_install_procedure ("plug_in_autocrop",
"Automagically crops a picture.",
"",
"Tim Newsome",
"Tim Newsome",
"1997",
N_("<Image>/Image/Transforms/Autocrop"),
"RGB*, GRAY*, INDEXED*",
GIMP_PLUGIN,
nargs, 0,
args, NULL);
}
static void
run (gchar *name,
gint n_params,
GimpParam *param,
gint *nreturn_vals,
GimpParam **return_vals)
{
static GimpParam values[1];
GimpDrawable *drawable;
GimpRunModeType run_mode;
GimpPDBStatusType status = GIMP_PDB_SUCCESS;
gint32 image_id;
gboolean interactive;
*nreturn_vals = 1;
*return_vals = values;
run_mode = param[0].data.d_int32;
interactive = (run_mode != GIMP_RUN_NONINTERACTIVE);
INIT_I18N();
if (n_params != 3)
{
status = GIMP_PDB_CALLING_ERROR;
goto out;
}
/* Get the specified drawable */
drawable = gimp_drawable_get (param[2].data.d_drawable);
image_id = param[1].data.d_image;
/* Make sure that the drawable is gray or RGB color */
if (gimp_drawable_is_rgb (drawable->id) ||
gimp_drawable_is_gray (drawable->id) ||
gimp_drawable_is_indexed (drawable->id))
{
if (interactive)
gimp_progress_init (_("Cropping..."));
gimp_tile_cache_ntiles (2 * (drawable->width / gimp_tile_width() + 1));
doit (drawable, image_id, interactive);
if (interactive)
gimp_displays_flush ();
}
else
{
status = GIMP_PDB_EXECUTION_ERROR;
}
out:
values[0].type = GIMP_PDB_STATUS;
values[0].data.d_status = status;
}
static void
doit (GimpDrawable *drawable,
gint32 image_id,
gboolean show_progress)
{
GimpPixelRgn srcPR;
gint width, height;
gint x, y, abort;
gint32 nx, ny, nw, nh;
guchar *buffer;
guchar color[4] = {0, 0, 0, 0};
width = drawable->width;
height = drawable->height;
bytes = drawable->bpp;
nx = 0;
ny = 0;
nw = width;
nh = height;
/* initialize the pixel regions */
gimp_pixel_rgn_init (&srcPR, drawable, 0, 0, width, height, FALSE, FALSE);
/* First, let's figure out what exactly to crop. */
buffer = g_malloc ((width > height ? width : height) * bytes);
guess_bgcolor (&srcPR, width, height, bytes, color);
/* Check how many of the top lines are uniform. */
abort = 0;
for (y = 0; y < height && !abort; y++)
{
gimp_pixel_rgn_get_row (&srcPR, buffer, 0, y, width);
for (x = 0; x < width && !abort; x++)
{
abort = !colors_equal (color, buffer + x * bytes, bytes);
}
}
if (y == height && !abort)
{
g_free (buffer);
gimp_drawable_detach (drawable);
return;
}
y--;
ny = y;
nh = height - y;
if (show_progress)
gimp_progress_update (0.25);
/* Check how many of the bottom lines are uniform. */
abort = 0;
for (y = height - 1; y >= 0 && !abort; y--)
{
gimp_pixel_rgn_get_row (&srcPR, buffer, 0, y, width);
for (x = 0; x < width && !abort; x++)
{
abort = !colors_equal (color, buffer + x * bytes, bytes);
}
}
nh = y - ny + 2;
if (show_progress)
gimp_progress_update (0.5);
/* Check how many of the left lines are uniform. */
abort = 0;
for (x = 0; x < width && !abort; x++)
{
gimp_pixel_rgn_get_col (&srcPR, buffer, x, ny, nh);
for (y = 0; y < nh && !abort; y++)
{
abort = !colors_equal (color, buffer + y * bytes, bytes);
}
}
x--;
nx = x;
nw = width - x;
if (show_progress)
gimp_progress_update (0.75);
/* Check how many of the right lines are uniform. */
abort = 0;
for (x = width - 1; x >= 0 && !abort; x--)
{
gimp_pixel_rgn_get_col (&srcPR, buffer, x, ny, nh);
for (y = 0; y < nh && !abort; y++)
{
abort = !colors_equal (color, buffer + y * bytes, bytes);
}
}
nw = x - nx + 2;
g_free (buffer);
gimp_drawable_detach (drawable);
if (nw != width || nh != height)
gimp_crop (image_id, nw, nh, nx, ny);
if (show_progress)
gimp_progress_update (1.00);
}
static gint
guess_bgcolor (GimpPixelRgn *pr,
gint width,
gint height,
gint bytes,
guchar *color)
{
guchar tl[4], tr[4], bl[4], br[4];
gimp_pixel_rgn_get_pixel (pr, tl, 0, 0);
gimp_pixel_rgn_get_pixel (pr, tr, width - 1, 0);
gimp_pixel_rgn_get_pixel (pr, bl, 0, height - 1);
gimp_pixel_rgn_get_pixel (pr, br, width - 1, height - 1);
/* Algorithm pinched from pnmcrop.
* To guess the background, first see if 3 corners are equal.
* Then if two are equal.
* Otherwise average the colors.
*/
if (colors_equal (tr, bl, bytes) && colors_equal (tr, br, bytes))
{
memcpy (color, tr, bytes);
return 3;
}
else if (colors_equal (tl, bl, bytes) && colors_equal (tl, br, bytes))
{
memcpy (color, tl, bytes);
return 3;
}
else if (colors_equal (tl, tr, bytes) && colors_equal (tl, br, bytes))
{
memcpy (color, tl, bytes);
return 3;
}
else if (colors_equal (tl, tr, bytes) && colors_equal (tl, bl, bytes))
{
memcpy (color, tl, bytes);
return 3;
}
else if (colors_equal (tl, tr, bytes) || colors_equal (tl, bl, bytes) ||
colors_equal (tl, br, bytes))
{
memcpy (color, tl, bytes);
return 2;
}
else if (colors_equal (tr, bl, bytes) || colors_equal (tr, bl, bytes))
{
memcpy (color, tr, bytes);
return 2;
}
else if (colors_equal (br, bl, bytes))
{
memcpy (color, br, bytes);
return 2;
}
else
{
while (bytes--)
{
color[bytes] = (tl[bytes] + tr[bytes] + bl[bytes] + br[bytes]) / 4;
}
return 0;
}
}
static gint
colors_equal (guchar *col1,
guchar *col2,
gint bytes)
{
gint equal = 1;
gint b;
if ((bytes == 2 || bytes == 4) && /* HACK! */
col1[bytes-1] == 0 &&
col2[bytes-1] == 0)
{
return 1; /* handle zero alpha */
}
for (b = 0; b < bytes; b++)
{
if (col1[b] != col2[b])
{
equal = 0;
break;
}
}
return equal;
}