/* PIKA - Photo and Image Kooker Application
* a rebranding of The GNU Image Manipulation Program (created with heckimp)
* A derived work which may be trivial. However, any changes may be (C)2023 by Aldercone Studio
*
* Original copyright, applying to most contents (license remains unchanged):
* Copyright (C) 1995 Spencer Kimball and Peter Mattis
*
* Portable Network Graphics (PNG) plug-in
*
* Copyright 1997-1998 Michael Sweet (mike@easysw.com) and
* Daniel Skarda (0rfelyus@atrey.karlin.mff.cuni.cz).
* and 1999-2000 Nick Lamb (njl195@zepler.org.uk)
*
* This program 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.
*
* This program 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 this program. If not, see .
*/
#include "config.h"
#include
#include
#include
#include "lcms2.h"
#include
#include
#include
#include "libpika/stdplugins-intl.h"
#define LOAD_PROC "file-png-load"
#define SAVE_PROC "file-png-save"
#define PLUG_IN_BINARY "file-png"
#define PLUG_IN_ROLE "pika-file-png"
#define PLUG_IN_VERSION "1.3.4 - 03 September 2002"
#define SCALE_WIDTH 125
#define DEFAULT_GAMMA 2.20
typedef enum _PngExportformat
{
PNG_FORMAT_AUTO = 0,
PNG_FORMAT_RGB8,
PNG_FORMAT_GRAY8,
PNG_FORMAT_RGBA8,
PNG_FORMAT_GRAYA8,
PNG_FORMAT_RGB16,
PNG_FORMAT_GRAY16,
PNG_FORMAT_RGBA16,
PNG_FORMAT_GRAYA16
} PngExportFormat;
static GSList *safe_to_copy_chunks;
typedef struct _Png Png;
typedef struct _PngClass PngClass;
struct _Png
{
PikaPlugIn parent_instance;
};
struct _PngClass
{
PikaPlugInClass parent_class;
};
#define PNG_TYPE (png_get_type ())
#define PNG(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), PNG_TYPE, Png))
GType png_get_type (void) G_GNUC_CONST;
static GList * png_query_procedures (PikaPlugIn *plug_in);
static PikaProcedure * png_create_procedure (PikaPlugIn *plug_in,
const gchar *name);
static PikaValueArray * png_load (PikaProcedure *procedure,
PikaRunMode run_mode,
GFile *file,
PikaMetadata *metadata,
PikaMetadataLoadFlags *flags,
PikaProcedureConfig *config,
gpointer run_data);
static PikaValueArray * png_save (PikaProcedure *procedure,
PikaRunMode run_mode,
PikaImage *image,
gint n_drawables,
PikaDrawable **drawables,
GFile *file,
PikaMetadata *metadata,
PikaProcedureConfig *config,
gpointer run_data);
static PikaImage * load_image (GFile *file,
gboolean report_progress,
gboolean *resolution_loaded,
gboolean *profile_loaded,
GError **error);
static gboolean save_image (GFile *file,
PikaImage *image,
PikaDrawable *drawable,
PikaImage *orig_image,
GObject *config,
gint *bits_per_sample,
gboolean report_progress,
GError **error);
static int respin_cmap (png_structp pp,
png_infop info,
guchar *remap,
PikaImage *image,
PikaDrawable *drawable);
static gboolean save_dialog (PikaImage *image,
PikaProcedure *procedure,
GObject *config,
gboolean alpha);
static gboolean offsets_dialog (gint offset_x,
gint offset_y);
static gboolean ia_has_transparent_pixels (GeglBuffer *buffer);
static gint find_unused_ia_color (GeglBuffer *buffer,
gint *colors);
static gint read_unknown_chunk (png_structp png_ptr,
png_unknown_chunkp chunk);
G_DEFINE_TYPE (Png, png, PIKA_TYPE_PLUG_IN)
PIKA_MAIN (PNG_TYPE)
DEFINE_STD_SET_I18N
static void
png_class_init (PngClass *klass)
{
PikaPlugInClass *plug_in_class = PIKA_PLUG_IN_CLASS (klass);
plug_in_class->query_procedures = png_query_procedures;
plug_in_class->create_procedure = png_create_procedure;
plug_in_class->set_i18n = STD_SET_I18N;
}
static void
png_init (Png *png)
{
}
static GList *
png_query_procedures (PikaPlugIn *plug_in)
{
GList *list = NULL;
list = g_list_append (list, g_strdup (LOAD_PROC));
list = g_list_append (list, g_strdup (SAVE_PROC));
return list;
}
static PikaProcedure *
png_create_procedure (PikaPlugIn *plug_in,
const gchar *name)
{
PikaProcedure *procedure = NULL;
if (! strcmp (name, LOAD_PROC))
{
procedure = pika_load_procedure_new (plug_in, name,
PIKA_PDB_PROC_TYPE_PLUGIN,
png_load, NULL, NULL);
pika_procedure_set_menu_label (procedure, _("PNG image"));
pika_procedure_set_documentation (procedure,
"Loads files in PNG file format",
"This plug-in loads Portable Network "
"Graphics (PNG) files.",
name);
pika_procedure_set_attribution (procedure,
"Michael Sweet , "
"Daniel Skarda <0rfelyus@atrey.karlin.mff.cuni.cz>",
"Michael Sweet , "
"Daniel Skarda <0rfelyus@atrey.karlin.mff.cuni.cz>, "
"Nick Lamb ",
PLUG_IN_VERSION);
pika_file_procedure_set_mime_types (PIKA_FILE_PROCEDURE (procedure),
"image/png");
pika_file_procedure_set_extensions (PIKA_FILE_PROCEDURE (procedure),
"png");
pika_file_procedure_set_magics (PIKA_FILE_PROCEDURE (procedure),
"0,string,\211PNG\r\n\032\n");
}
else if (! strcmp (name, SAVE_PROC))
{
procedure = pika_save_procedure_new (plug_in, name,
PIKA_PDB_PROC_TYPE_PLUGIN,
TRUE, png_save, NULL, NULL);
pika_procedure_set_image_types (procedure, "*");
pika_procedure_set_menu_label (procedure, _("PNG image"));
pika_procedure_set_documentation (procedure,
"Exports files in PNG file format",
"This plug-in exports Portable Network "
"Graphics (PNG) files.",
name);
pika_procedure_set_attribution (procedure,
"Michael Sweet , "
"Daniel Skarda <0rfelyus@atrey.karlin.mff.cuni.cz>",
"Michael Sweet , "
"Daniel Skarda <0rfelyus@atrey.karlin.mff.cuni.cz>, "
"Nick Lamb ",
PLUG_IN_VERSION);
pika_file_procedure_set_format_name (PIKA_FILE_PROCEDURE (procedure),
_("PNG"));
pika_file_procedure_set_mime_types (PIKA_FILE_PROCEDURE (procedure),
"image/png");
pika_file_procedure_set_extensions (PIKA_FILE_PROCEDURE (procedure),
"png");
PIKA_PROC_ARG_BOOLEAN (procedure, "interlaced",
_("_Interlacing (Adam7)"),
_("Use Adam7 interlacing"),
FALSE,
G_PARAM_READWRITE);
PIKA_PROC_ARG_INT (procedure, "compression",
_("Co_mpression level"),
_("Deflate Compression factor (0..9)"),
0, 9, 9,
G_PARAM_READWRITE);
PIKA_PROC_ARG_BOOLEAN (procedure, "bkgd",
_("Save _background color"),
_("Write bKGD chunk (PNG metadata)"),
TRUE,
G_PARAM_READWRITE);
PIKA_PROC_ARG_BOOLEAN (procedure, "offs",
_("Save layer o_ffset"),
_("Write oFFs chunk (PNG metadata)"),
FALSE,
G_PARAM_READWRITE);
PIKA_PROC_ARG_BOOLEAN (procedure, "phys",
_("Save resol_ution"),
_("Write pHYs chunk (PNG metadata)"),
TRUE,
G_PARAM_READWRITE);
PIKA_PROC_ARG_BOOLEAN (procedure, "time",
_("Save creation _time"),
_("Write tIME chunk (PNG metadata)"),
TRUE,
G_PARAM_READWRITE);
PIKA_PROC_ARG_BOOLEAN (procedure, "save-transparent",
_("Save color _values from transparent pixels"),
_("Preserve color of completely transparent pixels"),
FALSE,
G_PARAM_READWRITE);
PIKA_PROC_ARG_BOOLEAN (procedure, "optimize-palette",
_("_Optimize for smallest possible palette size"),
_("When checked, save as 1, 2, 4, or 8-bit depending"
" on number of colors used. When unchecked, always"
" save as 8-bit"),
FALSE,
G_PARAM_READWRITE);
PIKA_PROC_AUX_ARG_CHOICE (procedure, "format",
_("_Pixel format"),
_("PNG export format"),
pika_choice_new_with_values ("auto", PNG_FORMAT_AUTO, _("Automatic"), NULL,
"rgb8", PNG_FORMAT_RGB8, _("8 bpc RGB"), NULL,
"gray8", PNG_FORMAT_GRAY8, _("8 bpc GRAY"), NULL,
"rgba8", PNG_FORMAT_RGBA8, _("8 bpc RGBA"), NULL,
"graya8", PNG_FORMAT_GRAYA8, _("8 bpc GRAYA"), NULL,
"rgb16", PNG_FORMAT_RGB16, _("16 bpc RGB"), NULL,
"gray16", PNG_FORMAT_GRAY16, _("16 bpc GRAY"), NULL,
"rgba16", PNG_FORMAT_RGBA16, _("16 bpc RGBA"), NULL,
"graya16", PNG_FORMAT_GRAYA16, _("16 bpc GRAYA"), NULL,
NULL),
"auto", G_PARAM_READWRITE);
pika_save_procedure_set_support_exif (PIKA_SAVE_PROCEDURE (procedure), TRUE);
pika_save_procedure_set_support_iptc (PIKA_SAVE_PROCEDURE (procedure), TRUE);
pika_save_procedure_set_support_xmp (PIKA_SAVE_PROCEDURE (procedure), TRUE);
#if defined(PNG_iCCP_SUPPORTED)
pika_save_procedure_set_support_profile (PIKA_SAVE_PROCEDURE (procedure), TRUE);
#endif
pika_save_procedure_set_support_thumbnail (PIKA_SAVE_PROCEDURE (procedure), TRUE);
pika_save_procedure_set_support_comment (PIKA_SAVE_PROCEDURE (procedure), TRUE);
}
return procedure;
}
static PikaValueArray *
png_load (PikaProcedure *procedure,
PikaRunMode run_mode,
GFile *file,
PikaMetadata *metadata,
PikaMetadataLoadFlags *flags,
PikaProcedureConfig *config,
gpointer run_data)
{
PikaValueArray *return_vals;
gboolean report_progress = FALSE;
gboolean resolution_loaded = FALSE;
gboolean profile_loaded = FALSE;
PikaImage *image;
GError *error = NULL;
gegl_init (NULL, NULL);
if (run_mode != PIKA_RUN_NONINTERACTIVE)
{
pika_ui_init (PLUG_IN_BINARY);
report_progress = TRUE;
}
image = load_image (file,
report_progress,
&resolution_loaded,
&profile_loaded,
&error);
if (! image)
return pika_procedure_new_return_values (procedure,
PIKA_PDB_EXECUTION_ERROR,
error);
if (resolution_loaded)
*flags &= ~PIKA_METADATA_LOAD_RESOLUTION;
if (profile_loaded)
*flags &= ~PIKA_METADATA_LOAD_COLORSPACE;
return_vals = pika_procedure_new_return_values (procedure,
PIKA_PDB_SUCCESS,
NULL);
PIKA_VALUES_SET_IMAGE (return_vals, 1, image);
return return_vals;
}
static PikaValueArray *
png_save (PikaProcedure *procedure,
PikaRunMode run_mode,
PikaImage *image,
gint n_drawables,
PikaDrawable **drawables,
GFile *file,
PikaMetadata *metadata,
PikaProcedureConfig *config,
gpointer run_data)
{
PikaPDBStatusType status = PIKA_PDB_SUCCESS;
PikaExportReturn export = PIKA_EXPORT_CANCEL;
PikaImage *orig_image;
gboolean alpha;
GError *error = NULL;
gegl_init (NULL, NULL);
orig_image = image;
switch (run_mode)
{
case PIKA_RUN_INTERACTIVE:
case PIKA_RUN_WITH_LAST_VALS:
pika_ui_init (PLUG_IN_BINARY);
export = pika_export_image (&image, &n_drawables, &drawables, "PNG",
PIKA_EXPORT_CAN_HANDLE_RGB |
PIKA_EXPORT_CAN_HANDLE_GRAY |
PIKA_EXPORT_CAN_HANDLE_INDEXED |
PIKA_EXPORT_CAN_HANDLE_ALPHA);
if (export == PIKA_EXPORT_CANCEL)
return pika_procedure_new_return_values (procedure, PIKA_PDB_CANCEL,
NULL);
break;
default:
break;
}
if (n_drawables != 1)
{
/* PNG images have no layer concept. Export image should have a
* single drawable selected.
*/
g_set_error (&error, G_FILE_ERROR, 0,
_("PNG format does not support multiple layers."));
return pika_procedure_new_return_values (procedure,
PIKA_PDB_CALLING_ERROR,
error);
}
alpha = pika_drawable_has_alpha (drawables[0]);
/* If the image has no transparency, then there is usually no need
* to save a bKGD chunk. For more information, see:
* http://bugzilla.gnome.org/show_bug.cgi?id=92395
*/
if (! alpha)
g_object_set (config,
"bkgd", FALSE,
NULL);
if (run_mode == PIKA_RUN_INTERACTIVE)
{
if (! save_dialog (orig_image, procedure, G_OBJECT (config), alpha))
status = PIKA_PDB_CANCEL;
}
if (status == PIKA_PDB_SUCCESS)
{
gint bits_per_sample;
if (save_image (file, image, drawables[0], orig_image, G_OBJECT (config),
&bits_per_sample, run_mode != PIKA_RUN_NONINTERACTIVE,
&error))
{
if (metadata)
pika_metadata_set_bits_per_sample (metadata, bits_per_sample);
}
else
{
status = PIKA_PDB_EXECUTION_ERROR;
}
}
if (export == PIKA_EXPORT_EXPORT)
{
pika_image_delete (image);
g_free (drawables);
}
return pika_procedure_new_return_values (procedure, status, error);
}
struct read_error_data
{
guchar *pixel; /* Pixel data */
GeglBuffer *buffer; /* GEGL buffer for layer */
const Babl *file_format;
guint32 width; /* png_infop->width */
guint32 height; /* png_infop->height */
gint bpp; /* Bytes per pixel */
gint tile_height; /* Height of tile in PIKA */
gint begin; /* Beginning tile row */
gint end; /* Ending tile row */
gint num; /* Number of rows to load */
};
static void
on_read_error (png_structp png_ptr,
png_const_charp error_msg)
{
struct read_error_data *error_data = png_get_error_ptr (png_ptr);
gint begin;
gint end;
gint num;
g_printerr (_("Error loading PNG file: %s\n"), error_msg);
/* Flush the current half-read row of tiles */
gegl_buffer_set (error_data->buffer,
GEGL_RECTANGLE (0, error_data->begin,
error_data->width,
error_data->num),
0,
error_data->file_format,
error_data->pixel,
GEGL_AUTO_ROWSTRIDE);
begin = error_data->begin + error_data->tile_height;
if (begin < error_data->height)
{
end = MIN (error_data->end + error_data->tile_height, error_data->height);
num = end - begin;
gegl_buffer_clear (error_data->buffer,
GEGL_RECTANGLE (0, begin, error_data->width, num));
}
g_object_unref (error_data->buffer);
longjmp (png_jmpbuf (png_ptr), 1);
}
static int
get_bit_depth_for_palette (int num_palette)
{
if (num_palette <= 2)
return 1;
else if (num_palette <= 4)
return 2;
else if (num_palette <= 16)
return 4;
else
return 8;
}
static PikaColorProfile *
load_color_profile (png_structp pp,
png_infop info,
gchar **profile_name)
{
PikaColorProfile *profile = NULL;
#if defined(PNG_iCCP_SUPPORTED)
png_uint_32 proflen;
png_charp profname;
png_bytep prof;
int profcomp;
if (png_get_iCCP (pp, info, &profname, &profcomp, &prof, &proflen))
{
profile = pika_color_profile_new_from_icc_profile ((guint8 *) prof,
proflen, NULL);
if (profile && profname)
{
*profile_name = g_convert (profname, strlen (profname),
"ISO-8859-1", "UTF-8", NULL, NULL, NULL);
}
}
#endif
return profile;
}
/* Copied from src/cmsvirt.c in Little-CMS. */
static cmsToneCurve *
Build_sRGBGamma (cmsContext ContextID)
{
cmsFloat64Number Parameters[5];
Parameters[0] = 2.4;
Parameters[1] = 1. / 1.055;
Parameters[2] = 0.055 / 1.055;
Parameters[3] = 1. / 12.92;
Parameters[4] = 0.04045;
return cmsBuildParametricToneCurve (ContextID, 4, Parameters);
}
/*
* 'load_image()' - Load a PNG image into a new image window.
*/
static PikaImage *
load_image (GFile *file,
gboolean report_progress,
gboolean *resolution_loaded,
gboolean *profile_loaded,
GError **error)
{
gint i; /* Looping var */
gint trns; /* Transparency present */
gint bpp; /* Bytes per pixel */
gint width; /* image width */
gint height; /* image height */
gint num_passes; /* Number of interlace passes in file */
gint pass; /* Current pass in file */
gint tile_height; /* Height of tile in PIKA */
gint begin; /* Beginning tile row */
gint end; /* Ending tile row */
gint num; /* Number of rows to load */
PikaImageBaseType image_type; /* Type of image */
PikaPrecision image_precision; /* Precision of image */
PikaImageType layer_type; /* Type of drawable/layer */
PikaColorProfile *profile = NULL; /* Color profile */
gchar *profile_name = NULL; /* Profile's name */
FILE *fp; /* File pointer */
volatile PikaImage *image = NULL; /* Image -- protected for setjmp() */
PikaLayer *layer; /* Layer */
GeglBuffer *buffer; /* GEGL buffer for layer */
const Babl *file_format; /* BABL format for layer */
png_structp pp; /* PNG read pointer */
png_infop info; /* PNG info pointers */
png_voidp user_chunkp; /* PNG unknown chunk pointer */
guchar **pixels; /* Pixel rows */
guchar *pixel; /* Pixel data */
guchar alpha[256]; /* Index -> Alpha */
png_textp text;
gint num_texts;
struct read_error_data error_data;
safe_to_copy_chunks = NULL;
pp = png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (! pp)
{
/* this could happen if the compile time and run-time libpng
versions do not match. */
g_set_error (error, G_FILE_ERROR, 0,
_("Error creating PNG read struct while loading '%s'."),
pika_file_get_utf8_name (file));
return NULL;
}
info = png_create_info_struct (pp);
if (! info)
{
g_set_error (error, G_FILE_ERROR, 0,
_("Error while reading '%s'. Could not create PNG header info structure."),
pika_file_get_utf8_name (file));
return NULL;
}
if (setjmp (png_jmpbuf (pp)))
{
g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
_("Error while reading '%s'. File corrupted?"),
pika_file_get_utf8_name (file));
return (PikaImage *) image;
}
#ifdef PNG_BENIGN_ERRORS_SUPPORTED
/* Change some libpng errors to warnings (e.g. bug 721135) */
png_set_benign_errors (pp, TRUE);
/* bug 765850 */
png_set_option (pp, PNG_SKIP_sRGB_CHECK_PROFILE, PNG_OPTION_ON);
#endif
/*
* Open the file and initialize the PNG read "engine"...
*/
if (report_progress)
pika_progress_init_printf (_("Opening '%s'"),
pika_file_get_utf8_name (file));
fp = g_fopen (g_file_peek_path (file), "rb");
if (fp == NULL)
{
g_set_error (error, G_FILE_ERROR, g_file_error_from_errno (errno),
_("Could not open '%s' for reading: %s"),
pika_file_get_utf8_name (file), g_strerror (errno));
return NULL;
}
png_init_io (pp, fp);
png_set_compression_buffer_size (pp, 512);
/* Set up callback to save "safe to copy" chunks */
png_set_keep_unknown_chunks (pp, PNG_HANDLE_CHUNK_IF_SAFE, NULL, 0);
user_chunkp = png_get_user_chunk_ptr (pp);
png_set_read_user_chunk_fn (pp, user_chunkp, read_unknown_chunk);
/*
* Get the image info
*/
png_read_info (pp, info);
if (G_BYTE_ORDER == G_LITTLE_ENDIAN)
png_set_swap (pp);
/*
* Get the iCCP (color profile) chunk, if any.
*/
profile = load_color_profile (pp, info, &profile_name);
if (! profile && ! png_get_valid (pp, info, PNG_INFO_sRGB) &&
(png_get_valid (pp, info, PNG_INFO_gAMA) ||
png_get_valid (pp, info, PNG_INFO_cHRM)))
{
/* This is kind of a special case for PNG. If an image has no
* profile, and the sRGB chunk is not set, and either gAMA or cHRM
* (or ideally both) are set, then we generate a profile from
* these data on import. See #3265.
*/
cmsToneCurve *gamma_curve[3];
cmsCIExyY whitepoint;
cmsCIExyYTRIPLE primaries;
cmsHPROFILE cms_profile = NULL;
gdouble gamma = 1.0 / DEFAULT_GAMMA;
if (png_get_valid (pp, info, PNG_INFO_gAMA) &&
png_get_gAMA (pp, info, &gamma) == PNG_INFO_gAMA)
{
gamma_curve[0] = gamma_curve[1] = gamma_curve[2] = cmsBuildGamma (NULL, 1.0 / gamma);
}
else
{
/* Use the sRGB gamma curve. */
gamma_curve[0] = gamma_curve[1] = gamma_curve[2] = Build_sRGBGamma (NULL);
}
if (png_get_valid (pp, info, PNG_INFO_cHRM) &&
png_get_cHRM (pp, info, &whitepoint.x, &whitepoint.y,
&primaries.Red.x, &primaries.Red.y,
&primaries.Green.x, &primaries.Green.y,
&primaries.Blue.x, &primaries.Blue.y) == PNG_INFO_cHRM)
{
whitepoint.Y = primaries.Red.Y = primaries.Green.Y = primaries.Blue.Y = 1.0;
}
else
{
/* Rec709 primaries and D65 whitepoint as copied from
* cmsCreate_sRGBProfileTHR() in Little-CMS.
*/
cmsCIExyY d65_whitepoint = { 0.3127, 0.3290, 1.0 };
cmsCIExyYTRIPLE rec709_primaries =
{
{0.6400, 0.3300, 1.0},
{0.3000, 0.6000, 1.0},
{0.1500, 0.0600, 1.0}
};
memcpy (&whitepoint, &d65_whitepoint, sizeof whitepoint);
memcpy (&primaries, &rec709_primaries, sizeof primaries);
}
if (png_get_color_type (pp, info) == PNG_COLOR_TYPE_GRAY ||
png_get_color_type (pp, info) == PNG_COLOR_TYPE_GRAY_ALPHA)
cms_profile = cmsCreateGrayProfile (&whitepoint, gamma_curve[0]);
else /* RGB, RGB with Alpha and Indexed. */
cms_profile = cmsCreateRGBProfile (&whitepoint, &primaries, gamma_curve);
cmsFreeToneCurve (gamma_curve[0]);
g_warn_if_fail (cms_profile != NULL);
if (cms_profile != NULL)
{
/* Customize the profile description to show it is generated
* from PNG metadata.
*/
gchar *profile_desc;
cmsMLU *description_mlu;
cmsContext context_id = cmsGetProfileContextID (cms_profile);
/* Note that I am not trying to localize these strings on purpose
* because cmsMLUsetASCII() expects ASCII. Maybe we should move to
* using cmsMLUsetWide() if we want the generated profile
* descriptions to be localized. XXX
*/
if ((png_get_valid (pp, info, PNG_INFO_gAMA) && png_get_valid (pp, info, PNG_INFO_cHRM)))
profile_desc = g_strdup_printf ("Generated %s profile from PNG's gAMA (gamma %.4f) and cHRM chunks",
(png_get_color_type (pp, info) == PNG_COLOR_TYPE_GRAY ||
png_get_color_type (pp, info) == PNG_COLOR_TYPE_GRAY_ALPHA) ?
"grayscale" : "RGB", 1.0 / gamma);
else if (png_get_valid (pp, info, PNG_INFO_gAMA))
profile_desc = g_strdup_printf ("Generated %s profile from PNG's gAMA chunk (gamma %.4f)",
(png_get_color_type (pp, info) == PNG_COLOR_TYPE_GRAY ||
png_get_color_type (pp, info) == PNG_COLOR_TYPE_GRAY_ALPHA) ?
"grayscale" : "RGB", 1.0 / gamma);
else
profile_desc = g_strdup_printf ("Generated %s profile from PNG's cHRM chunk",
(png_get_color_type (pp, info) == PNG_COLOR_TYPE_GRAY ||
png_get_color_type (pp, info) == PNG_COLOR_TYPE_GRAY_ALPHA) ?
"grayscale" : "RGB");
description_mlu = cmsMLUalloc (context_id, 1);
cmsMLUsetASCII (description_mlu, "en", "US", profile_desc);
cmsWriteTag (cms_profile, cmsSigProfileDescriptionTag, description_mlu);
profile = pika_color_profile_new_from_lcms_profile (cms_profile, NULL);
g_free (profile_desc);
cmsMLUfree (description_mlu);
cmsCloseProfile (cms_profile);
}
}
if (profile)
*profile_loaded = TRUE;
/*
* Get image precision and color model.
* Note that we always import PNG as non-linear. The data might be
* actually linear because of a linear profile, or because of a gAMA
* chunk with 1.0 value (which we convert to a profile above). But
* then we'll just set the right profile and that's it. Other than
* this, PNG doesn't have (that I can see in the spec) any kind of
* flag saying that data is linear, bypassing the profile's TRC so
* there is basically no reason to explicitly set a linear precision.
*/
if (png_get_bit_depth (pp, info) == 16)
image_precision = PIKA_PRECISION_U16_NON_LINEAR;
else
image_precision = PIKA_PRECISION_U8_NON_LINEAR;
if (png_get_bit_depth (pp, info) < 8)
{
if (png_get_color_type (pp, info) == PNG_COLOR_TYPE_GRAY)
png_set_expand (pp);
if (png_get_color_type (pp, info) == PNG_COLOR_TYPE_PALETTE)
png_set_packing (pp);
}
/*
* Expand G+tRNS to GA, RGB+tRNS to RGBA
*/
if (png_get_color_type (pp, info) != PNG_COLOR_TYPE_PALETTE &&
png_get_valid (pp, info, PNG_INFO_tRNS))
png_set_expand (pp);
/*
* Turn on interlace handling... libpng returns just 1 (ie single pass)
* if the image is not interlaced
*/
num_passes = png_set_interlace_handling (pp);
/*
* Special handling for INDEXED + tRNS (transparency palette)
*/
if (png_get_valid (pp, info, PNG_INFO_tRNS) &&
png_get_color_type (pp, info) == PNG_COLOR_TYPE_PALETTE)
{
guchar *alpha_ptr;
png_get_tRNS (pp, info, &alpha_ptr, &num, NULL);
/* Copy the existing alpha values from the tRNS chunk */
for (i = 0; i < num; ++i)
alpha[i] = alpha_ptr[i];
/* And set any others to fully opaque (255) */
for (i = num; i < 256; ++i)
alpha[i] = 255;
trns = 1;
}
else
{
trns = 0;
}
/*
* Update the info structures after the transformations take effect
*/
png_read_update_info (pp, info);
switch (png_get_color_type (pp, info))
{
case PNG_COLOR_TYPE_RGB:
image_type = PIKA_RGB;
layer_type = PIKA_RGB_IMAGE;
break;
case PNG_COLOR_TYPE_RGB_ALPHA:
image_type = PIKA_RGB;
layer_type = PIKA_RGBA_IMAGE;
break;
case PNG_COLOR_TYPE_GRAY:
image_type = PIKA_GRAY;
layer_type = PIKA_GRAY_IMAGE;
break;
case PNG_COLOR_TYPE_GRAY_ALPHA:
image_type = PIKA_GRAY;
layer_type = PIKA_GRAYA_IMAGE;
break;
case PNG_COLOR_TYPE_PALETTE:
image_type = PIKA_INDEXED;
layer_type = PIKA_INDEXED_IMAGE;
break;
default:
g_set_error (error, G_FILE_ERROR, 0,
_("Unknown color model in PNG file '%s'."),
pika_file_get_utf8_name (file));
return NULL;
}
width = png_get_image_width (pp, info);
height = png_get_image_height (pp, info);
image = pika_image_new_with_precision (width, height,
image_type, image_precision);
if (! image)
{
g_set_error (error, G_FILE_ERROR, 0,
_("Could not create new image for '%s': %s"),
pika_file_get_utf8_name (file),
pika_pdb_get_last_error (pika_get_pdb ()));
return NULL;
}
/*
* Attach the color profile, if any
*/
if (profile)
{
pika_image_set_color_profile ((PikaImage *) image, profile);
g_object_unref (profile);
if (profile_name)
{
PikaParasite *parasite;
parasite = pika_parasite_new ("icc-profile-name",
PIKA_PARASITE_PERSISTENT |
PIKA_PARASITE_UNDOABLE,
strlen (profile_name),
profile_name);
pika_image_attach_parasite ((PikaImage *) image, parasite);
pika_parasite_free (parasite);
g_free (profile_name);
}
}
/*
* Create the "background" layer to hold the image...
*/
layer = pika_layer_new ((PikaImage *) image, _("Background"), width, height,
layer_type,
100,
pika_image_get_default_new_layer_mode ((PikaImage *) image));
pika_image_insert_layer ((PikaImage *) image, layer, NULL, 0);
file_format = pika_drawable_get_format (PIKA_DRAWABLE (layer));
/*
* Find out everything we can about the image resolution
* This is only practical with the new 1.0 APIs, I'm afraid
* due to a bug in libpng-1.0.6, see png-implement for details
*/
if (png_get_valid (pp, info, PNG_INFO_oFFs))
{
gint offset_x = png_get_x_offset_pixels (pp, info);
gint offset_y = png_get_y_offset_pixels (pp, info);
if (offset_x != 0 ||
offset_y != 0)
{
if (! report_progress)
{
pika_layer_set_offsets (layer, offset_x, offset_y);
}
else if (offsets_dialog (offset_x, offset_y))
{
pika_layer_set_offsets (layer, offset_x, offset_y);
if (abs (offset_x) > width ||
abs (offset_y) > height)
{
g_message (_("The PNG file specifies an offset that caused "
"the layer to be positioned outside the image."));
}
}
}
}
if (png_get_valid (pp, info, PNG_INFO_pHYs))
{
png_uint_32 xres;
png_uint_32 yres;
gint unit_type;
if (png_get_pHYs (pp, info,
&xres, &yres, &unit_type) && xres > 0 && yres > 0)
{
switch (unit_type)
{
case PNG_RESOLUTION_UNKNOWN:
{
gdouble image_xres, image_yres;
pika_image_get_resolution ((PikaImage *) image, &image_xres, &image_yres);
if (xres > yres)
image_xres = image_yres * (gdouble) xres / (gdouble) yres;
else
image_yres = image_xres * (gdouble) yres / (gdouble) xres;
pika_image_set_resolution ((PikaImage *) image, image_xres, image_yres);
*resolution_loaded = TRUE;
}
break;
case PNG_RESOLUTION_METER:
pika_image_set_resolution ((PikaImage *) image,
(gdouble) xres * 0.0254,
(gdouble) yres * 0.0254);
pika_image_set_unit ((PikaImage *) image, PIKA_UNIT_MM);
*resolution_loaded = TRUE;
break;
default:
break;
}
}
}
/*
* Load the colormap as necessary...
*/
if (png_get_color_type (pp, info) & PNG_COLOR_MASK_PALETTE)
{
png_colorp palette;
int num_palette;
png_get_PLTE (pp, info, &palette, &num_palette);
pika_image_set_colormap ((PikaImage *) image, (guchar *) palette,
num_palette);
}
bpp = babl_format_get_bytes_per_pixel (file_format);
buffer = pika_drawable_get_buffer (PIKA_DRAWABLE (layer));
/*
* Temporary buffer...
*/
tile_height = pika_tile_height ();
pixel = g_new0 (guchar, tile_height * width * bpp);
pixels = g_new (guchar *, tile_height);
for (i = 0; i < tile_height; i++)
pixels[i] = pixel + width * bpp * i;
/* Install our own error handler to handle incomplete PNG files better */
error_data.buffer = buffer;
error_data.pixel = pixel;
error_data.file_format = file_format;
error_data.tile_height = tile_height;
error_data.width = width;
error_data.height = height;
error_data.bpp = bpp;
png_set_error_fn (pp, &error_data, on_read_error, NULL);
for (pass = 0; pass < num_passes; pass++)
{
/*
* This works if you are only reading one row at a time...
*/
for (begin = 0; begin < height; begin += tile_height)
{
end = MIN (begin + tile_height, height);
num = end - begin;
if (pass != 0) /* to handle interlaced PiNGs */
gegl_buffer_get (buffer,
GEGL_RECTANGLE (0, begin, width, num),
1.0,
file_format,
pixel,
GEGL_AUTO_ROWSTRIDE,
GEGL_ABYSS_NONE);
error_data.begin = begin;
error_data.end = end;
error_data.num = num;
png_read_rows (pp, pixels, NULL, num);
gegl_buffer_set (buffer,
GEGL_RECTANGLE (0, begin, width, num),
0,
file_format,
pixel,
GEGL_AUTO_ROWSTRIDE);
if (report_progress)
pika_progress_update (((gdouble) pass +
(gdouble) end / (gdouble) height) /
(gdouble) num_passes);
}
}
png_read_end (pp, info);
/* Switch back to default error handler */
png_set_error_fn (pp, NULL, NULL, NULL);
if (png_get_text (pp, info, &text, &num_texts))
{
gchar *comment = NULL;
for (i = 0; i < num_texts && !comment; i++, text++)
{
if (text->key == NULL || strcmp (text->key, "Comment"))
continue;
if (text->text_length > 0) /* tEXt */
{
comment = g_convert (text->text, -1,
"UTF-8", "ISO-8859-1",
NULL, NULL, NULL);
}
else if (g_utf8_validate (text->text, -1, NULL))
{ /* iTXt */
comment = g_strdup (text->text);
}
}
if (comment && *comment)
{
PikaParasite *parasite;
parasite = pika_parasite_new ("pika-comment",
PIKA_PARASITE_PERSISTENT,
strlen (comment) + 1, comment);
pika_image_attach_parasite ((PikaImage *) image, parasite);
pika_parasite_free (parasite);
}
g_free (comment);
}
/*
* Done with the file...
*/
png_destroy_read_struct (&pp, &info, NULL);
g_free (pixel);
g_free (pixels);
g_object_unref (buffer);
free (pp);
free (info);
fclose (fp);
if (trns)
{
GeglBufferIterator *iter;
gint n_components;
pika_layer_add_alpha (layer);
buffer = pika_drawable_get_buffer (PIKA_DRAWABLE (layer));
file_format = gegl_buffer_get_format (buffer);
iter = gegl_buffer_iterator_new (buffer, NULL, 0, file_format,
GEGL_ACCESS_READWRITE, GEGL_ABYSS_NONE, 1);
n_components = babl_format_get_n_components (file_format);
g_warn_if_fail (n_components == 2);
while (gegl_buffer_iterator_next (iter))
{
guchar *data = iter->items[0].data;
gint length = iter->length;
while (length--)
{
data[1] = alpha[data[0]];
data += n_components;
}
}
g_object_unref (buffer);
}
/* If any safe-to-copy chunks were saved,
* store them in the image as parasite */
if (safe_to_copy_chunks)
{
GSList *iter;
for (iter = safe_to_copy_chunks; iter; iter = iter->next)
{
PikaParasite *parasite = iter->data;
pika_image_attach_parasite ((PikaImage *) image, parasite);
pika_parasite_free (parasite);
}
g_slist_free (safe_to_copy_chunks);
}
return (PikaImage *) image;
}
/*
* 'offsets_dialog ()' - Asks the user about offsets when loading.
*/
static gboolean
offsets_dialog (gint offset_x,
gint offset_y)
{
GtkWidget *dialog;
GtkWidget *hbox;
GtkWidget *image;
GtkWidget *label;
gchar *message;
gboolean run;
pika_ui_init (PLUG_IN_BINARY);
dialog = pika_dialog_new (_("Apply PNG Offset"), PLUG_IN_ROLE,
NULL, 0,
pika_standard_help_func, LOAD_PROC,
_("Ignore PNG offset"), GTK_RESPONSE_NO,
_("Apply PNG offset to layer"), GTK_RESPONSE_YES,
NULL);
gtk_dialog_set_default_response (GTK_DIALOG (dialog), GTK_RESPONSE_YES);
pika_dialog_set_alternative_button_order (GTK_DIALOG (dialog),
GTK_RESPONSE_YES,
GTK_RESPONSE_NO,
-1);
pika_window_set_transient (GTK_WINDOW (dialog));
gtk_window_set_resizable (GTK_WINDOW (dialog), FALSE);
hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 12);
gtk_container_set_border_width (GTK_CONTAINER (hbox), 12);
gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dialog))),
hbox, FALSE, FALSE, 0);
gtk_widget_show (hbox);
image = gtk_image_new_from_icon_name (PIKA_ICON_DIALOG_QUESTION,
GTK_ICON_SIZE_DIALOG);
gtk_widget_set_valign (image, GTK_ALIGN_START);
gtk_box_pack_start (GTK_BOX (hbox), image, FALSE, FALSE, 0);
gtk_widget_show (image);
message = g_strdup_printf (_("The PNG image you are importing specifies an "
"offset of %d, %d. Do you want to apply "
"this offset to the layer?"),
offset_x, offset_y);
label = gtk_label_new (message);
gtk_label_set_yalign (GTK_LABEL (label), 0.0);
gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
gtk_box_pack_start (GTK_BOX (hbox), label, TRUE, TRUE, 0);
gtk_widget_show (label);
gtk_widget_show (dialog);
run = (pika_dialog_run (PIKA_DIALOG (dialog)) == GTK_RESPONSE_YES);
gtk_widget_destroy (dialog);
return run;
}
/*
* 'save_image ()' - Export the specified image to a PNG file.
*/
typedef struct
{
gboolean has_trns;
png_bytep trans;
int num_trans;
gboolean has_plte;
png_colorp palette;
int num_palette;
}
PngGlobals;
static PngGlobals pngg;
static gboolean
save_image (GFile *file,
PikaImage *image,
PikaDrawable *drawable,
PikaImage *orig_image,
GObject *config,
gint *bits_per_sample,
gboolean report_progress,
GError **error)
{
gint i, k; /* Looping vars */
gint bpp = 0; /* Bytes per pixel */
gint type; /* Type of drawable/layer */
gint num_passes; /* Number of interlace passes in file */
gint pass; /* Current pass in file */
gint tile_height; /* Height of tile in PIKA */
gint width; /* image width */
gint height; /* image height */
gint begin; /* Beginning tile row */
gint end; /* Ending tile row */
gint num; /* Number of rows to load */
FILE *fp; /* File pointer */
PikaColorProfile *profile = NULL; /* Color profile */
gchar **parasites; /* Safe-to-copy chunks */
gboolean out_linear; /* Save linear RGB */
GeglBuffer *buffer; /* GEGL buffer for layer */
const Babl *file_format = NULL; /* BABL format of file */
const gchar *encoding;
const Babl *space;
png_structp pp; /* PNG read pointer */
png_infop info; /* PNG info pointer */
gint offx, offy; /* Drawable offsets from origin */
guchar **pixels; /* Pixel rows */
guchar *fixed; /* Fixed-up pixel data */
guchar *pixel; /* Pixel data */
gdouble xres, yres; /* PIKA resolution (dpi) */
png_color_16 background; /* Background color */
png_time mod_time; /* Modification time (ie NOW) */
time_t cutime; /* Time since epoch */
struct tm *gmt; /* GMT broken down */
gint color_type; /* PNG color type */
gint bit_depth; /* Default to bit depth 16 */
guchar remap[256]; /* Re-mapping for the palette */
png_textp text = NULL;
gboolean save_interlaced;
gboolean save_bkgd;
gboolean save_offs;
gboolean save_phys;
gboolean save_time;
gboolean save_comment;
gchar *comment;
gboolean save_transp_pixels;
gboolean optimize_palette;
gint compression_level;
PngExportFormat export_format;
gboolean save_profile;
#if !defined(PNG_iCCP_SUPPORTED)
g_object_set (config,
"save-color-profile", FALSE,
NULL);
#endif
g_object_get (config,
"interlaced", &save_interlaced,
"bkgd", &save_bkgd,
"offs", &save_offs,
"phys", &save_phys,
"time", &save_time,
"save-comment", &save_comment,
"pika-comment", &comment,
"save-transparent", &save_transp_pixels,
"optimize-palette", &optimize_palette,
"compression", &compression_level,
"save-color-profile", &save_profile,
NULL);
export_format = pika_procedure_config_get_choice_id (PIKA_PROCEDURE_CONFIG (config), "format");
out_linear = FALSE;
space = pika_drawable_get_format (drawable);
#if defined(PNG_iCCP_SUPPORTED)
/* If no profile is written: export as sRGB.
* If manually assigned profile written: follow its TRC.
* If default profile written:
* - when export as auto or 16-bit: follow the storage TRC.
* - when export from 8-bit storage: follow the storage TRC.
* - when converting high bit depth to 8-bit: export as sRGB.
*/
if (save_profile)
{
profile = pika_image_get_color_profile (orig_image);
if (profile ||
export_format == PNG_FORMAT_AUTO ||
export_format == PNG_FORMAT_RGB16 ||
export_format == PNG_FORMAT_RGBA16 ||
export_format == PNG_FORMAT_GRAY16 ||
export_format == PNG_FORMAT_GRAYA16 ||
pika_image_get_precision (image) == PIKA_PRECISION_U8_LINEAR ||
pika_image_get_precision (image) == PIKA_PRECISION_U8_NON_LINEAR ||
pika_image_get_precision (image) == PIKA_PRECISION_U8_PERCEPTUAL)
{
if (! profile)
profile = pika_image_get_effective_color_profile (orig_image);
out_linear = (pika_color_profile_is_linear (profile));
}
else
{
/* When converting higher bit depth work image into 8-bit,
* with no manually assigned profile, make sure the result is
* sRGB.
*/
profile = pika_image_get_effective_color_profile (orig_image);
if (pika_color_profile_is_linear (profile))
{
PikaColorProfile *saved_profile;
saved_profile = pika_color_profile_new_srgb_trc_from_color_profile (profile);
g_object_unref (profile);
profile = saved_profile;
}
}
space = pika_color_profile_get_space (profile,
PIKA_COLOR_RENDERING_INTENT_RELATIVE_COLORIMETRIC,
error);
if (error && *error)
{
/* XXX: the profile space should normally be the same one as
* the drawable's so let's continue with it. We were mostly
* getting the profile space to be complete. Still let's
* display the error to standard error channel because if the
* space could not be extracted, there is a problem somewhere!
*/
g_printerr ("%s: error getting the profile space: %s",
G_STRFUNC, (*error)->message);
g_clear_error (error);
space = pika_drawable_get_format (drawable);
}
}
#endif
/* We save as 8-bit PNG only if:
* (1) Work image is 8-bit linear with linear profile to be saved.
* (2) Work image is 8-bit non-linear or perceptual with or without
* profile.
*/
bit_depth = 16;
switch (pika_image_get_precision (image))
{
case PIKA_PRECISION_U8_LINEAR:
if (out_linear)
bit_depth = 8;
break;
case PIKA_PRECISION_U8_NON_LINEAR:
case PIKA_PRECISION_U8_PERCEPTUAL:
if (! out_linear)
bit_depth = 8;
break;
default:
break;
}
pp = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if (!pp)
{
/* this could happen if the compile time and run-time libpng
* versions do not match.
*/
g_set_error (error, G_FILE_ERROR, 0,
_("Error creating PNG write struct while exporting '%s'."),
pika_file_get_utf8_name (file));
return FALSE;
}
info = png_create_info_struct (pp);
if (! info)
{
g_set_error (error, G_FILE_ERROR, 0,
_("Error while exporting '%s'. Could not create PNG header info structure."),
pika_file_get_utf8_name (file));
return FALSE;
}
if (setjmp (png_jmpbuf (pp)))
{
g_set_error (error, G_FILE_ERROR, 0,
_("Error while exporting '%s'. Could not export image."),
pika_file_get_utf8_name (file));
return FALSE;
}
#ifdef PNG_BENIGN_ERRORS_SUPPORTED
/* Change some libpng errors to warnings (e.g. bug 721135) */
png_set_benign_errors (pp, TRUE);
/* bug 765850 */
png_set_option (pp, PNG_SKIP_sRGB_CHECK_PROFILE, PNG_OPTION_ON);
#endif
/*
* Open the file and initialize the PNG write "engine"...
*/
if (report_progress)
pika_progress_init_printf (_("Exporting '%s'"),
pika_file_get_utf8_name (file));
fp = g_fopen (g_file_peek_path (file), "wb");
if (! fp)
{
g_set_error (error, G_FILE_ERROR, g_file_error_from_errno (errno),
_("Could not open '%s' for writing: %s"),
pika_file_get_utf8_name (file), g_strerror (errno));
return FALSE;
}
png_init_io (pp, fp);
/*
* Get the buffer for the current image...
*/
buffer = pika_drawable_get_buffer (drawable);
width = gegl_buffer_get_width (buffer);
height = gegl_buffer_get_height (buffer);
type = pika_drawable_type (drawable);
/*
* Initialise remap[]
*/
for (i = 0; i < 256; i++)
remap[i] = i;
if (export_format == PNG_FORMAT_AUTO)
{
/*
* Set color type and remember bytes per pixel count
*/
switch (type)
{
case PIKA_RGB_IMAGE:
color_type = PNG_COLOR_TYPE_RGB;
if (bit_depth == 8)
{
if (out_linear)
encoding = "RGB u8";
else
encoding = "R'G'B' u8";
}
else
{
if (out_linear)
encoding = "RGB u16";
else
encoding = "R'G'B' u16";
}
break;
case PIKA_RGBA_IMAGE:
color_type = PNG_COLOR_TYPE_RGB_ALPHA;
if (bit_depth == 8)
{
if (out_linear)
encoding = "RGBA u8";
else
encoding = "R'G'B'A u8";
}
else
{
if (out_linear)
encoding = "RGBA u16";
else
encoding = "R'G'B'A u16";
}
break;
case PIKA_GRAY_IMAGE:
color_type = PNG_COLOR_TYPE_GRAY;
if (bit_depth == 8)
{
if (out_linear)
encoding = "Y u8";
else
encoding = "Y' u8";
}
else
{
if (out_linear)
encoding = "Y u16";
else
encoding = "Y' u16";
}
break;
case PIKA_GRAYA_IMAGE:
color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
if (bit_depth == 8)
{
if (out_linear)
encoding = "YA u8";
else
encoding = "Y'A u8";
}
else
{
if (out_linear)
encoding = "YA u16";
else
encoding = "Y'A u16";
}
break;
case PIKA_INDEXED_IMAGE:
color_type = PNG_COLOR_TYPE_PALETTE;
file_format = pika_drawable_get_format (drawable);
pngg.has_plte = TRUE;
pngg.palette = (png_colorp) pika_image_get_colormap (image,
NULL,
&pngg.num_palette);
if (optimize_palette)
bit_depth = get_bit_depth_for_palette (pngg.num_palette);
break;
case PIKA_INDEXEDA_IMAGE:
color_type = PNG_COLOR_TYPE_PALETTE;
file_format = pika_drawable_get_format (drawable);
/* fix up transparency */
if (optimize_palette)
bit_depth = respin_cmap (pp, info, remap, image, drawable);
else
respin_cmap (pp, info, remap, image, drawable);
break;
default:
g_set_error (error, G_FILE_ERROR, 0, "Image type can't be exported as PNG");
return FALSE;
}
}
else
{
switch (export_format)
{
case PNG_FORMAT_RGB8:
color_type = PNG_COLOR_TYPE_RGB;
if (out_linear)
encoding = "RGB u8";
else
encoding = "R'G'B' u8";
bit_depth = 8;
break;
case PNG_FORMAT_GRAY8:
color_type = PNG_COLOR_TYPE_GRAY;
if (out_linear)
encoding = "Y u8";
else
encoding = "Y' u8";
bit_depth = 8;
break;
case PNG_FORMAT_RGBA8:
color_type = PNG_COLOR_TYPE_RGB_ALPHA;
if (out_linear)
encoding = "RGBA u8";
else
encoding = "R'G'B'A u8";
bit_depth = 8;
break;
case PNG_FORMAT_GRAYA8:
color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
if (out_linear)
encoding = "YA u8";
else
encoding = "Y'A u8";
bit_depth = 8;
break;
case PNG_FORMAT_RGB16:
color_type = PNG_COLOR_TYPE_RGB;
if (out_linear)
encoding = "RGB u16";
else
encoding = "R'G'B' u16";
bit_depth = 16;
break;
case PNG_FORMAT_GRAY16:
color_type = PNG_COLOR_TYPE_GRAY;
if (out_linear)
encoding = "Y u16";
else
encoding = "Y' u16";
bit_depth = 16;
break;
case PNG_FORMAT_RGBA16:
color_type = PNG_COLOR_TYPE_RGB_ALPHA;
if (out_linear)
encoding = "RGBA u16";
else
encoding = "R'G'B'A u16";
bit_depth = 16;
break;
case PNG_FORMAT_GRAYA16:
color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
if (out_linear)
encoding = "YA u16";
else
encoding = "Y'A u16";
bit_depth = 16;
break;
case PNG_FORMAT_AUTO:
g_return_val_if_reached (FALSE);
}
}
if (! file_format)
file_format = babl_format_with_space (encoding, space);
bpp = babl_format_get_bytes_per_pixel (file_format);
/* Note: png_set_IHDR() must be called before any other png_set_*()
functions. */
png_set_IHDR (pp, info, width, height, bit_depth, color_type,
save_interlaced ? PNG_INTERLACE_ADAM7 : PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_BASE,
PNG_FILTER_TYPE_BASE);
if (pngg.has_trns)
png_set_tRNS (pp, info, pngg.trans, pngg.num_trans, NULL);
if (pngg.has_plte)
png_set_PLTE (pp, info, pngg.palette, pngg.num_palette);
/* Set the compression level */
png_set_compression_level (pp, compression_level);
/* All this stuff is optional extras, if the user is aiming for smallest
possible file size she can turn them all off */
if (save_bkgd)
{
PikaRGB color;
guchar red, green, blue;
pika_context_get_background (&color);
pika_rgb_get_uchar (&color, &red, &green, &blue);
background.index = 0;
background.red = red;
background.green = green;
background.blue = blue;
background.gray = pika_rgb_luminance_uchar (&color);
png_set_bKGD (pp, info, &background);
}
if (save_offs)
{
pika_drawable_get_offsets (drawable, &offx, &offy);
if (offx != 0 || offy != 0)
png_set_oFFs (pp, info, offx, offy, PNG_OFFSET_PIXEL);
}
if (save_phys)
{
pika_image_get_resolution (orig_image, &xres, &yres);
png_set_pHYs (pp, info, RINT (xres / 0.0254), RINT (yres / 0.0254),
PNG_RESOLUTION_METER);
}
if (save_time)
{
cutime = time (NULL); /* time right NOW */
gmt = gmtime (&cutime);
mod_time.year = gmt->tm_year + 1900;
mod_time.month = gmt->tm_mon + 1;
mod_time.day = gmt->tm_mday;
mod_time.hour = gmt->tm_hour;
mod_time.minute = gmt->tm_min;
mod_time.second = gmt->tm_sec;
png_set_tIME (pp, info, &mod_time);
}
#if defined(PNG_iCCP_SUPPORTED)
if (save_profile)
{
PikaParasite *parasite;
gchar *profile_name = NULL;
const guint8 *icc_data;
gsize icc_length;
icc_data = pika_color_profile_get_icc_profile (profile, &icc_length);
parasite = pika_image_get_parasite (orig_image,
"icc-profile-name");
if (parasite)
{
gchar *parasite_data;
guint32 parasite_size;
parasite_data = (gchar *) pika_parasite_get_data (parasite, ¶site_size);
profile_name = g_convert (parasite_data, parasite_size,
"UTF-8", "ISO-8859-1", NULL, NULL, NULL);
}
png_set_iCCP (pp,
info,
profile_name ? profile_name : "ICC profile",
0,
icc_data,
icc_length);
g_free (profile_name);
g_object_unref (profile);
}
else
#endif
{
/* Be more specific by writing into the file that the image is in
* sRGB color space.
*/
PikaColorConfig *config = pika_get_color_configuration ();
int srgb_intent;
switch (pika_color_config_get_display_intent (config))
{
case PIKA_COLOR_RENDERING_INTENT_PERCEPTUAL:
srgb_intent = PNG_sRGB_INTENT_PERCEPTUAL;
break;
case PIKA_COLOR_RENDERING_INTENT_RELATIVE_COLORIMETRIC:
srgb_intent = PNG_sRGB_INTENT_RELATIVE;
break;
case PIKA_COLOR_RENDERING_INTENT_SATURATION:
srgb_intent = PNG_sRGB_INTENT_SATURATION;
break;
case PIKA_COLOR_RENDERING_INTENT_ABSOLUTE_COLORIMETRIC:
srgb_intent = PNG_sRGB_INTENT_ABSOLUTE;
break;
}
png_set_sRGB_gAMA_and_cHRM (pp, info, srgb_intent);
g_object_unref (config);
}
#ifdef PNG_zTXt_SUPPORTED
/* Small texts are not worth compressing and will be even bigger if compressed.
Empirical length limit of a text being worth compressing. */
#define COMPRESSION_WORTHY_LENGTH 200
#endif
if (save_comment && comment && strlen (comment))
{
gsize text_length = 0;
text = g_new0 (png_text, 1);
text[0].key = "Comment";
#ifdef PNG_iTXt_SUPPORTED
text[0].text = g_convert (comment, -1,
"ISO-8859-1",
"UTF-8",
NULL,
&text_length,
NULL);
if (text[0].text == NULL || strlen (text[0].text) == 0)
{
/* We can't convert to ISO-8859-1 without loss.
* Save the comment as iTXt (UTF-8).
*/
g_free (text[0].text);
text[0].text = g_strdup (comment);
text[0].itxt_length = strlen (text[0].text);
#ifdef PNG_zTXt_SUPPORTED
text[0].compression = strlen (text[0].text) > COMPRESSION_WORTHY_LENGTH ?
PNG_ITXT_COMPRESSION_zTXt : PNG_ITXT_COMPRESSION_NONE;
#else
text[0].compression = PNG_ITXT_COMPRESSION_NONE;
#endif /* PNG_zTXt_SUPPORTED */
}
else
/* The comment is ISO-8859-1 compatible, so we use tEXt even
* if there is iTXt support for compatibility to more png
* reading programs.
*/
#endif /* PNG_iTXt_SUPPORTED */
{
#ifndef PNG_iTXt_SUPPORTED
/* No iTXt support, so we are forced to use tEXt
* (ISO-8859-1). A broken comment is better than no comment
* at all, so the conversion does not fail on unknown
* character. They are simply ignored.
*/
text[0].text = g_convert_with_fallback (comment, -1,
"ISO-8859-1",
"UTF-8",
"",
NULL,
&text_length,
NULL);
#endif
#ifdef PNG_zTXt_SUPPORTED
text[0].compression = strlen (text[0].text) > COMPRESSION_WORTHY_LENGTH ?
PNG_TEXT_COMPRESSION_zTXt : PNG_TEXT_COMPRESSION_NONE;
#else
text[0].compression = PNG_TEXT_COMPRESSION_NONE;
#endif /* PNG_zTXt_SUPPORTED */
text[0].text_length = text_length;
}
if (! text[0].text || strlen (text[0].text) == 0)
{
g_free (text[0].text);
g_free (text);
text = NULL;
}
}
g_free (comment);
#ifdef PNG_zTXt_SUPPORTED
#undef COMPRESSION_WORTHY_LENGTH
#endif
if (text)
png_set_text (pp, info, text, 1);
png_write_info (pp, info);
if (G_BYTE_ORDER == G_LITTLE_ENDIAN)
png_set_swap (pp);
/* Write any safe-to-copy chunks saved from import */
parasites = pika_image_get_parasite_list (image);
if (parasites)
{
gint count;
count = g_strv_length (parasites);
for (gint i = 0; i < count; i++)
{
if (strncmp (parasites[i], "png", 3) == 0)
{
PikaParasite *parasite;
parasite = pika_image_get_parasite (image, parasites[i]);
if (parasite)
{
gchar buf[1024];
gchar *chunk_name;
g_strlcpy (buf, parasites[i], sizeof (buf));
chunk_name = strchr (buf, '/');
chunk_name++;
if (chunk_name)
{
png_byte name[4];
const guint8 *data;
guint32 len;
for (gint j = 0; j < 4; j++)
name[j] = chunk_name[j];
data = (const guint8 *) pika_parasite_get_data (parasite, &len);
png_write_chunk (pp, name, data, len);
}
pika_parasite_free (parasite);
}
}
}
}
g_strfreev (parasites);
/*
* Turn on interlace handling...
*/
if (save_interlaced)
num_passes = png_set_interlace_handling (pp);
else
num_passes = 1;
/*
* Convert unpacked pixels to packed if necessary
*/
if (color_type == PNG_COLOR_TYPE_PALETTE &&
bit_depth < 8)
png_set_packing (pp);
/*
* Allocate memory for "tile_height" rows and export the image...
*/
tile_height = pika_tile_height ();
pixel = g_new (guchar, tile_height * width * bpp);
pixels = g_new (guchar *, tile_height);
for (i = 0; i < tile_height; i++)
pixels[i] = pixel + width * bpp * i;
for (pass = 0; pass < num_passes; pass++)
{
/* This works if you are only writing one row at a time... */
for (begin = 0, end = tile_height;
begin < height; begin += tile_height, end += tile_height)
{
if (end > height)
end = height;
num = end - begin;
gegl_buffer_get (buffer,
GEGL_RECTANGLE (0, begin, width, num),
1.0,
file_format,
pixel,
GEGL_AUTO_ROWSTRIDE,
GEGL_ABYSS_NONE);
/* If we are with a RGBA image and have to pre-multiply the
alpha channel */
if (bpp == 4 && ! save_transp_pixels)
{
for (i = 0; i < num; ++i)
{
fixed = pixels[i];
for (k = 0; k < width; ++k)
{
if (!fixed[3])
fixed[0] = fixed[1] = fixed[2] = 0;
fixed += bpp;
}
}
}
if (bpp == 8 && ! save_transp_pixels)
{
for (i = 0; i < num; ++i)
{
fixed = pixels[i];
for (k = 0; k < width; ++k)
{
if (!fixed[6] && !fixed[7])
fixed[0] = fixed[1] = fixed[2] =
fixed[3] = fixed[4] = fixed[5] = 0;
fixed += bpp;
}
}
}
/* If we're dealing with a paletted image with
* transparency set, write out the remapped palette */
if (png_get_valid (pp, info, PNG_INFO_tRNS))
{
guchar inverse_remap[256];
for (i = 0; i < 256; i++)
inverse_remap[ remap[i] ] = i;
for (i = 0; i < num; ++i)
{
fixed = pixels[i];
for (k = 0; k < width; ++k)
{
fixed[k] = (fixed[k*2+1] > 127) ?
inverse_remap[ fixed[k*2] ] :
0;
}
}
}
/* Otherwise if we have a paletted image and transparency
* couldn't be set, we ignore the alpha channel */
else if (png_get_valid (pp, info, PNG_INFO_PLTE) &&
bpp == 2)
{
for (i = 0; i < num; ++i)
{
fixed = pixels[i];
for (k = 0; k < width; ++k)
{
fixed[k] = fixed[k * 2];
}
}
}
png_write_rows (pp, pixels, num);
if (report_progress)
pika_progress_update (((double) pass + (double) end /
(double) height) /
(double) num_passes);
}
}
if (report_progress)
pika_progress_update (1.0);
png_write_end (pp, info);
png_destroy_write_struct (&pp, &info);
g_free (pixel);
g_free (pixels);
/*
* Done with the file...
*/
if (text)
{
g_free (text[0].text);
g_free (text);
}
free (pp);
free (info);
fclose (fp);
*bits_per_sample = bit_depth;
return TRUE;
}
static gboolean
ia_has_transparent_pixels (GeglBuffer *buffer)
{
GeglBufferIterator *iter;
const Babl *format;
gint n_components;
format = gegl_buffer_get_format (buffer);
iter = gegl_buffer_iterator_new (buffer, NULL, 0, format,
GEGL_ACCESS_READ, GEGL_ABYSS_NONE, 1);
n_components = babl_format_get_n_components (format);
g_return_val_if_fail (n_components == 2, FALSE);
while (gegl_buffer_iterator_next (iter))
{
const guchar *data = iter->items[0].data;
gint length = iter->length;
while (length--)
{
if (data[1] <= 127)
{
gegl_buffer_iterator_stop (iter);
return TRUE;
}
data += n_components;
}
}
return FALSE;
}
/* Try to find a color in the palette which isn't actually used in the
* image, so that we can use it as the transparency index. Taken from
* gif.c
*/
static gint
find_unused_ia_color (GeglBuffer *buffer,
gint *colors)
{
GeglBufferIterator *iter;
const Babl *format;
gint n_components;
gboolean ix_used[256];
gboolean trans_used = FALSE;
gint i;
for (i = 0; i < *colors; i++)
ix_used[i] = FALSE;
format = gegl_buffer_get_format (buffer);
iter = gegl_buffer_iterator_new (buffer, NULL, 0, format,
GEGL_ACCESS_READ, GEGL_ABYSS_NONE, 1);
n_components = babl_format_get_n_components (format);
g_return_val_if_fail (n_components == 2, FALSE);
while (gegl_buffer_iterator_next (iter))
{
const guchar *data = iter->items[0].data;
gint length = iter->length;
while (length--)
{
if (data[1] > 127)
ix_used[data[0]] = TRUE;
else
trans_used = TRUE;
data += n_components;
}
}
/* If there is no transparency, ignore alpha. */
if (trans_used == FALSE)
return -1;
/* If there is still some room at the end of the palette, increment
* the number of colors in the image and assign a transparent pixel
* there.
*/
if ((*colors) < 256)
{
(*colors)++;
return (*colors) - 1;
}
for (i = 0; i < *colors; i++)
{
if (ix_used[i] == FALSE)
return i;
}
return -1;
}
static int
respin_cmap (png_structp pp,
png_infop info,
guchar *remap,
PikaImage *image,
PikaDrawable *drawable)
{
static guchar trans[] = { 0 };
GeglBuffer *buffer;
gint colors;
guchar *before;
before = pika_image_get_colormap (image, NULL, &colors);
buffer = pika_drawable_get_buffer (drawable);
/* Make sure there is something in the colormap.
*/
if (colors == 0)
{
before = g_newa (guchar, 3);
memset (before, 0, sizeof (guchar) * 3);
colors = 1;
}
/* Try to find an entry which isn't actually used in the image, for
* a transparency index.
*/
if (ia_has_transparent_pixels (buffer))
{
gint transparent = find_unused_ia_color (buffer, &colors);
if (transparent != -1) /* we have a winner for a transparent
* index - do like gif2png and swap
* index 0 and index transparent
*/
{
static png_color palette[256];
gint i;
/* Set tRNS chunk values for writing later. */
pngg.has_trns = TRUE;
pngg.trans = trans;
pngg.num_trans = 1;
/* Transform all pixels with a value = transparent to 0 and
* vice versa to compensate for re-ordering in palette due
* to png_set_tRNS()
*/
remap[0] = transparent;
for (i = 1; i <= transparent; i++)
remap[i] = i - 1;
/* Copy from index 0 to index transparent - 1 to index 1 to
* transparent of after, then from transparent+1 to colors-1
* unchanged, and finally from index transparent to index 0.
*/
for (i = 0; i < colors; i++)
{
palette[i].red = before[3 * remap[i]];
palette[i].green = before[3 * remap[i] + 1];
palette[i].blue = before[3 * remap[i] + 2];
}
/* Set PLTE chunk values for writing later. */
pngg.has_plte = TRUE;
pngg.palette = palette;
pngg.num_palette = colors;
}
else
{
/* Inform the user that we couldn't losslessly save the
* transparency & just use the full palette
*/
g_message (_("Couldn't losslessly save transparency, "
"saving opacity instead."));
/* Set PLTE chunk values for writing later. */
pngg.has_plte = TRUE;
pngg.palette = (png_colorp) before;
pngg.num_palette = colors;
}
}
else
{
/* Set PLTE chunk values for writing later. */
pngg.has_plte = TRUE;
pngg.palette = (png_colorp) before;
pngg.num_palette = colors;
}
g_object_unref (buffer);
return get_bit_depth_for_palette (colors);
}
static gint
read_unknown_chunk (png_structp png_ptr,
png_unknown_chunkp chunk)
{
/* Chunks with a lowercase letter in the 4th byte
* are safe to copy */
if (g_ascii_islower (chunk->name[3]))
{
PikaParasite *parasite;
gchar pname[255];
g_snprintf (pname, sizeof (pname), "png/%s", chunk->name);
if ((parasite = pika_parasite_new (pname,
PIKA_PARASITE_PERSISTENT,
chunk->size, chunk->data)))
safe_to_copy_chunks = g_slist_prepend (safe_to_copy_chunks, parasite);
}
return 0;
}
static gboolean
save_dialog (PikaImage *image,
PikaProcedure *procedure,
GObject *config,
gboolean alpha)
{
GtkWidget *dialog;
gboolean run;
gboolean indexed;
indexed = (pika_image_get_base_type (image) == PIKA_INDEXED);
dialog = pika_save_procedure_dialog_new (PIKA_SAVE_PROCEDURE (procedure),
PIKA_PROCEDURE_CONFIG (config),
image);
pika_procedure_dialog_get_widget (PIKA_PROCEDURE_DIALOG (dialog),
"compression", PIKA_TYPE_SPIN_SCALE);
pika_procedure_dialog_set_sensitive (PIKA_PROCEDURE_DIALOG (dialog),
"save-transparent",
alpha, NULL, NULL, FALSE);
pika_procedure_dialog_set_sensitive (PIKA_PROCEDURE_DIALOG (dialog),
"optimize-palette",
indexed, NULL, NULL, FALSE);
pika_save_procedure_dialog_add_metadata (PIKA_SAVE_PROCEDURE_DIALOG (dialog), "bkgd");
pika_save_procedure_dialog_add_metadata (PIKA_SAVE_PROCEDURE_DIALOG (dialog), "offs");
pika_save_procedure_dialog_add_metadata (PIKA_SAVE_PROCEDURE_DIALOG (dialog), "phys");
pika_save_procedure_dialog_add_metadata (PIKA_SAVE_PROCEDURE_DIALOG (dialog), "time");
pika_procedure_dialog_fill (PIKA_PROCEDURE_DIALOG (dialog),
"format", "compression",
"interlaced", "save-transparent",
"optimize-palette",
NULL);
run = pika_procedure_dialog_run (PIKA_PROCEDURE_DIALOG (dialog));
gtk_widget_destroy (dialog);
return run;
}