app: add support for loading Photoshop patterns

For now only RGB and grayscale are supported.
This commit is contained in:
Jacob Boerema 2025-05-23 15:26:15 -04:00
parent 934c4a90cd
commit 67f505009a

View file

@ -30,10 +30,327 @@
#include "gimppattern-header.h" #include "gimppattern-header.h"
#include "gimppattern-load.h" #include "gimppattern-load.h"
#include "gimptempbuf.h" #include "gimptempbuf.h"
#include "gimp-utils.h"
#include "gimp-intl.h" #include "gimp-intl.h"
GList *
gimp_pattern_load_photoshop_pattern (GimpContext *context,
GFile *file,
GInputStream *input,
GError **error)
{
gint16 version;
gint32 pat_count;
gint i;
goffset ofs;
GList *pattern_list = NULL;
GDataInputStream *data_input;
GError **last_error = NULL;
data_input = g_data_input_stream_new (input);
/* Photoshop data is big endian */
g_data_input_stream_set_byte_order (data_input,
G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN);
/* Reset stream position to right after magic (offset 4) */
if (! g_seekable_seek (G_SEEKABLE (input),
4, G_SEEK_SET,
NULL, error))
{
g_prefix_error (error, _("Error reading Photoshop pattern."));
return NULL;
}
if (! gimp_data_input_stream_read_short (data_input, &version, error) ||
! gimp_data_input_stream_read_long (data_input, &pat_count, error))
{
g_prefix_error (error, _("Error reading Photoshop pattern."));
return NULL;
}
g_debug ("\nDetected Photoshop pattern file. Version: %u, number of patterns: %u",
version, pat_count);
#define update_last_error() if (last_error) g_clear_error (last_error); last_error = error; error = NULL;
for (i = 0; i < pat_count; i++)
{
gint32 pat_version;
gint32 pat_image_type;
gint16 pat_height;
gint16 pat_width;
gchar *pat_name;
gint32 pat_size;
gint32 pat_top, pat_left, pat_bottom, pat_right;
gint32 pat_depth;
guint32 n_channels;
gint32 width, height;
gboolean can_handle;
can_handle = FALSE;
pat_name = NULL;
n_channels = 0;
if (! gimp_data_input_stream_read_long (data_input, &pat_version, error) ||
! gimp_data_input_stream_read_long (data_input, &pat_image_type, error) ||
! gimp_data_input_stream_read_short (data_input, &pat_height, error) ||
! gimp_data_input_stream_read_short (data_input, &pat_width, error) ||
! gimp_data_input_stream_read_ucs2_text (data_input, &pat_name, error))
{
g_printerr ("Error reading Photoshop pattern %d.\n", i);
update_last_error ();
break;
}
g_debug ("Pattern version %u, image type: %u, width x height: %u x %u, name: %s",
pat_version, pat_image_type, pat_width, pat_height, pat_name);
/* For now seek past pattern id, ideally we would read the length to make
* sure the size is as expected (length byte that usually says 36) */
if (! g_seekable_seek (G_SEEKABLE (input),
37, G_SEEK_CUR,
NULL, error))
{
g_printerr ("Error reading Photoshop pattern %d.\n", i);
update_last_error ();
break;
}
/* FIXME: Support for reading the palette if this is indexed */
if (pat_image_type == 2)
{
g_printerr ("Indexed Photoshop pattern is not yet supported.\n");
break;
}
if (! gimp_data_input_stream_read_long (data_input, &pat_version, error) ||
! gimp_data_input_stream_read_long (data_input, &pat_size, error))
{
g_printerr ("Error reading Photoshop pattern %d.\n", i);
update_last_error ();
break;
}
ofs = g_seekable_tell (G_SEEKABLE (input));
g_debug ("Pattern version %u, size: %u, offset: %llx, next %llx",
pat_version, pat_size, ofs, ofs + pat_size);
if (! gimp_data_input_stream_read_long (data_input, &pat_top, error) ||
! gimp_data_input_stream_read_long (data_input, &pat_left, error) ||
! gimp_data_input_stream_read_long (data_input, &pat_bottom, error) ||
! gimp_data_input_stream_read_long (data_input, &pat_right, error) ||
! gimp_data_input_stream_read_long (data_input, &pat_depth, error))
{
g_printerr ("Error reading Photoshop pattern %d.\n", i);
update_last_error ();
break;
}
g_debug ("(top,left)-(bottom,right): (%d,%d)-(%d,%d), bit depth: %d",
pat_top, pat_left, pat_bottom, pat_right, pat_depth);
/* It would be nice to have extra safety checks based on the reported depth,
* but it seems Photoshop sets depth to 24 even for grayscale and cmyk,
* independent of the actual number of channels; so we can't do that.
* (Possibly it will be 48 instead of 24 in case of 16-bit per channel.)
*/
if (pat_depth == 24)
{
switch (pat_image_type)
{
case 1: /* Grayscale */
n_channels = 1;
can_handle = TRUE;
break;
case 3: /* RGB*/
n_channels = 3;
can_handle = TRUE;
break;
}
}
else
{
g_printerr ("Unsupported Photoshop pattern depth %d.\n", pat_depth);
}
width = pat_right - pat_left;
height = pat_bottom - pat_top;
if ((width <= 0) || (width > GIMP_PATTERN_MAX_SIZE) ||
(height <= 0) || (height > GIMP_PATTERN_MAX_SIZE))
{
g_printerr ("Invalid or unsupported Photoshop pattern size %d x %d\n", width, height);
can_handle = FALSE;
}
if (can_handle)
{
GimpPattern *pattern;
const Babl *format;
gsize size, bytes_read;
gint chan;
guchar *chan_data;
guchar *chan_buf;
chan_buf = NULL;
format = NULL;
pattern = NULL;
/* Load pattern data */
pattern = g_object_new (GIMP_TYPE_PATTERN,
"name", pat_name,
"mime-type", "image/x-gimp-pat",
NULL);
switch (n_channels)
{
case 1: format = babl_format ("Y' u8"); break;
case 2: format = babl_format ("Y'A u8"); break;
case 3: format = babl_format ("R'G'B' u8"); break;
case 4: format = babl_format ("R'G'B'A u8"); break;
}
pattern->mask = gimp_temp_buf_new (width, height, format);
size = (gsize) width * height;
chan_buf = g_malloc (size);
if (! chan_buf)
{
g_printerr ("Cannot create buffer!\n");
break;
}
chan_data = gimp_temp_buf_get_data (pattern->mask);
for (chan = 0; chan < n_channels; chan++)
{
gint j;
goffset cofs;
gint32 chan_version;
gint32 chan_size;
gint32 chan_dummy;
gint16 chan_depth;
gint8 chan_compression;
gint32 chan_top, chan_left, chan_bottom, chan_right;
guchar *temp_buf;
temp_buf = NULL;
if (! gimp_data_input_stream_read_long (data_input, &chan_version, error) ||
! gimp_data_input_stream_read_long (data_input, &chan_size, error))
{
g_printerr ("Error reading channel %d of pattern %d\n", chan, i);
update_last_error ();
break;
}
cofs = g_seekable_tell (G_SEEKABLE (data_input));
/** Dummy 32-bit depth */
if (! gimp_data_input_stream_read_long (data_input, &chan_dummy, error))
{
g_printerr ("Error reading channel %d of pattern %d\n", chan, i);
update_last_error ();
break;
}
if (! gimp_data_input_stream_read_long (data_input, &chan_top, error) ||
! gimp_data_input_stream_read_long (data_input, &chan_left, error) ||
! gimp_data_input_stream_read_long (data_input, &chan_bottom, error) ||
! gimp_data_input_stream_read_long (data_input, &chan_right, error) ||
! gimp_data_input_stream_read_short (data_input, &chan_depth, error) ||
! gimp_data_input_stream_read_char (data_input, (gchar *) &chan_compression, error))
{
g_printerr ("Error reading channel %d of pattern %d\n", chan, i);
update_last_error ();
break;
}
if (chan_compression == 0)
{
if (! g_input_stream_read_all ((GInputStream *) data_input,
chan_buf, size,
&bytes_read, NULL, error) ||
bytes_read != size)
{
g_printerr ("Error reading channel %d of pattern %d\n", chan, i);
update_last_error ();
break;
}
}
else
{
if (! gimp_data_input_stream_rle_decode (data_input,
(gchar *) chan_buf, size,
height, error))
{
g_printerr ("Failed to decode channel %d of pattern %d.\n", chan, i);
update_last_error ();
break;
}
}
/* Move channel data to correct offset */
temp_buf = &chan_data[chan];
for (j = 0; j < size; j++)
{
temp_buf[j*n_channels] = chan_buf[j];
}
/* Always seek to next offset to reduce chance of errors */
if (! g_seekable_seek (G_SEEKABLE (data_input),
cofs+chan_size, G_SEEK_SET,
NULL, error))
{
g_printerr ("Error reading Photoshop pattern.\n");
update_last_error ();
break;
}
}
/* FIXME: An alpha channel (and possibly mask) may follow the normal channels...
* Maybe always add alpha and init to fully opaque?
*/
g_free (chan_buf);
if (pattern)
pattern_list = g_list_prepend (pattern_list, pattern);
}
else
{
/* Format not handled yet */
g_printerr ("Loading Photoshop patterns of type %d is not yet supported.\n",
pat_image_type);
}
g_free (pat_name);
/* In case we made a mistake reading a pattern: compute offset next pattern. */
if (! g_seekable_seek (G_SEEKABLE (input),
ofs+pat_size, G_SEEK_SET,
NULL, error))
{
g_printerr ("Failed to seek to next Photoshop pattern offset.\n");
update_last_error ();
break;
}
}
if (last_error && *last_error)
{
if (pattern_list == NULL)
{
/* Only return error if we didn't get any patterns. */
error = last_error;
}
else
{
g_clear_error (last_error);
}
}
return pattern_list;
}
GList * GList *
gimp_pattern_load (GimpContext *context, gimp_pattern_load (GimpContext *context,
GFile *file, GFile *file,
@ -61,6 +378,16 @@ gimp_pattern_load (GimpContext *context,
goto error; goto error;
} }
/* Check whether it is a Photoshop pattern */
if (memcmp (&header.header_size, "8BPT", 4) == 0)
{
GList *ps_patterns = NULL;
ps_patterns = gimp_pattern_load_photoshop_pattern (context, file, input, error);
return ps_patterns;
}
/* rearrange the bytes in each unsigned int */ /* rearrange the bytes in each unsigned int */
header.header_size = g_ntohl (header.header_size); header.header_size = g_ntohl (header.header_size);
header.version = g_ntohl (header.version); header.version = g_ntohl (header.version);