/* -*- mode: C; c-file-style: "linux" -*- */
/* GdkPixbuf library - Windows Bitmap image loader
*
* Copyright (C) 1999 The Free Software Foundation
*
* Authors: Arjan van de Ven <arjan@fenrus.demon.nl>
* Federico Mena-Quintero <federico@gimp.org>
*
* Based on io-ras.c
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <stdio.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <string.h>
#include "gdk-pixbuf-private.h"
#define DUMPBIH 0
#if 0
/* If these structures were unpacked, they would define the two headers of the
* BMP file. After them comes the palette, and then the image data.
*
* We do not use these structures; we just keep them here for reference.
*/
struct BitmapFileHeader {
guint16 magic;
guint32 file_size;
guint32 reserved;
guint32 data_offset;
};
struct BitmapInfoHeader {
guint32 header_size;
guint32 width;
guint32 height;
guint16 planes;
guint16 bpp;
guint32 compression;
guint32 data_size;
guint32 x_ppm;
guint32 y_ppm;
guint32 n_colors;
guint32 n_important_colors;
};
#endif
/* Compression values */
#define BI_RGB 0
#define BI_RLE8 1
#define BI_RLE4 2
#define BI_BITFIELDS 3
/* State machine */
typedef enum {
READ_STATE_HEADERS, /* Reading the bitmap file header and bitmap info header */
READ_STATE_PALETTE, /* Reading the palette */
READ_STATE_BITMASKS, /* Reading the bitmasks for BI_BITFIELDS */
READ_STATE_DATA, /* Reading the actual image data */
READ_STATE_ERROR, /* An error occurred; further data will be ignored */
READ_STATE_DONE /* Done reading the image; further data will be ignored */
} ReadState;
/*
DumpBIH printf's the values in a BitmapInfoHeader to the screen, for
debugging purposes.
*/
#if DUMPBIH
static void DumpBIH(unsigned char *BIH)
{
printf("biSize = %i \n",
(int) (BIH[3] << 24) + (BIH[2] << 16) + (BIH[1] << 8) +
(BIH[0]));
printf("biWidth = %i \n",
(int) (BIH[7] << 24) + (BIH[6] << 16) + (BIH[5] << 8) +
(BIH[4]));
printf("biHeight = %i \n",
(int) (BIH[11] << 24) + (BIH[10] << 16) + (BIH[9] << 8) +
(BIH[8]));
printf("biPlanes = %i \n", (int) (BIH[13] << 8) + (BIH[12]));
printf("biBitCount = %i \n", (int) (BIH[15] << 8) + (BIH[14]));
printf("biCompress = %i \n",
(int) (BIH[19] << 24) + (BIH[18] << 16) + (BIH[17] << 8) +
(BIH[16]));
printf("biSizeImage = %i \n",
(int) (BIH[23] << 24) + (BIH[22] << 16) + (BIH[21] << 8) +
(BIH[20]));
printf("biXPels = %i \n",
(int) (BIH[27] << 24) + (BIH[26] << 16) + (BIH[25] << 8) +
(BIH[24]));
printf("biYPels = %i \n",
(int) (BIH[31] << 24) + (BIH[30] << 16) + (BIH[29] << 8) +
(BIH[28]));
printf("biClrUsed = %i \n",
(int) (BIH[35] << 24) + (BIH[34] << 16) + (BIH[33] << 8) +
(BIH[32]));
printf("biClrImprtnt= %i \n",
(int) (BIH[39] << 24) + (BIH[38] << 16) + (BIH[37] << 8) +
(BIH[36]));
}
#endif
/* struct headerpair contains the decoded width/height/depth info for
the current bitmap */
struct headerpair {
guint32 size;
gint32 width;
gint32 height;
guint depth;
guint Negative; /* Negative = 1 -> top down BMP,
Negative = 0 -> bottom up BMP */
guint n_colors;
};
/* Data needed for the "state" during decompression */
struct bmp_compression_state {
gint phase;
gint run;
gint count;
gint x, y;
guchar *p;
};
/* Progressive loading */
struct bmp_progressive_state {
GdkPixbufModuleSizeFunc size_func;
GdkPixbufModulePreparedFunc prepared_func;
GdkPixbufModuleUpdatedFunc updated_func;
gpointer user_data;
ReadState read_state;
guint LineWidth;
guint Lines; /* # of finished lines */
guchar *buff;
guint BufferSize;
guint BufferPadding;
guint BufferDone;
guchar (*Colormap)[3];
gint Type; /*
32 = RGB + alpha
24 = RGB
16 = RGB
4 = 4 bpp colormapped
8 = 8 bpp colormapped
1 = 1 bit bitonal
*/
guint Compressed;
struct bmp_compression_state compr;
struct headerpair Header; /* Decoded (BE->CPU) header */
/* Bit masks, shift amounts, and significant bits for BI_BITFIELDS coding */
int r_mask, r_shift, r_bits;
int g_mask, g_shift, g_bits;
int b_mask, b_shift, b_bits;
int a_mask, a_shift, a_bits;
GdkPixbuf *pixbuf; /* Our "target" */
};
static gpointer
gdk_pixbuf__bmp_image_begin_load(GdkPixbufModuleSizeFunc size_func,
GdkPixbufModulePreparedFunc prepared_func,
GdkPixbufModuleUpdatedFunc updated_func,
gpointer user_data,
GError **error);
static gboolean gdk_pixbuf__bmp_image_stop_load(gpointer data, GError **error);
static gboolean gdk_pixbuf__bmp_image_load_increment(gpointer data,
const guchar * buf,
guint size,
GError **error);
/* Picks up a 32-bit little-endian integer starting at the specified location.
* Does it by hand instead of dereferencing a simple (gint *) cast due to
* alignment constraints many platforms.
*/
static int
lsb_32 (guchar *src)
{
return src[0] | (src[1] << 8) | (src[2] << 16) | (src[3] << 24);
}
/* Same as above, but for 16-bit little-endian integers. */
static short
lsb_16 (guchar *src)
{
return src[0] | (src[1] << 8);
}
static gboolean grow_buffer (struct bmp_progressive_state *State,
GError **error)
{
guchar *tmp;
if (State->BufferSize == 0) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has bogus header data"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
tmp = g_try_realloc (State->buff, State->BufferSize);
if (!tmp) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Not enough memory to load bitmap image"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
State->buff = tmp;
return TRUE;
}
static gboolean
decode_bitmasks (guchar *buf,
struct bmp_progressive_state *State,
GError **error);
static gboolean DecodeHeader(unsigned char *BFH, unsigned char *BIH,
struct bmp_progressive_state *State,
GError **error)
{
gint clrUsed;
guint bytesPerPixel;
/* First check for the two first bytes content. A sane
BMP file must start with bytes 0x42 0x4D. */
if (*BFH != 0x42 || *(BFH + 1) != 0x4D) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has bogus header data"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
/* FIXME this is totally unrobust against bogus image data. */
if (State->BufferSize < lsb_32 (&BIH[0]) + 14) {
State->BufferSize = lsb_32 (&BIH[0]) + 14;
if (!grow_buffer (State, error))
return FALSE;
return TRUE;
}
#if DUMPBIH
DumpBIH(BIH);
#endif
State->Header.size = lsb_32 (&BIH[0]);
if (State->Header.size == 124) {
/* BMP v5 */
State->Header.width = lsb_32 (&BIH[4]);
State->Header.height = lsb_32 (&BIH[8]);
State->Header.depth = lsb_16 (&BIH[14]);
State->Compressed = lsb_32 (&BIH[16]);
} else if (State->Header.size == 108) {
/* BMP v4 */
State->Header.width = lsb_32 (&BIH[4]);
State->Header.height = lsb_32 (&BIH[8]);
State->Header.depth = lsb_16 (&BIH[14]);
State->Compressed = lsb_32 (&BIH[16]);
} else if (State->Header.size == 64) {
/* BMP OS/2 v2 */
State->Header.width = lsb_32 (&BIH[4]);
State->Header.height = lsb_32 (&BIH[8]);
State->Header.depth = lsb_16 (&BIH[14]);
State->Compressed = lsb_32 (&BIH[16]);
} else if (State->Header.size == 56) {
/* BMP v3 with RGBA bitmasks */
State->Header.width = lsb_32 (&BIH[4]);
State->Header.height = lsb_32 (&BIH[8]);
State->Header.depth = lsb_16 (&BIH[14]);
State->Compressed = lsb_32 (&BIH[16]);
} else if (State->Header.size == 52) {
/* BMP v3 with RGB bitmasks */
State->Header.width = lsb_32 (&BIH[4]);
State->Header.height = lsb_32 (&BIH[8]);
State->Header.depth = lsb_16 (&BIH[14]);
State->Compressed = lsb_32 (&BIH[16]);
} else if (State->Header.size == 40) {
/* BMP v3 */
State->Header.width = lsb_32 (&BIH[4]);
State->Header.height = lsb_32 (&BIH[8]);
State->Header.depth = lsb_16 (&BIH[14]);
State->Compressed = lsb_32 (&BIH[16]);
} else if (State->Header.size == 12) {
/* BMP OS/2 */
State->Header.width = lsb_16 (&BIH[4]);
State->Header.height = lsb_16 (&BIH[6]);
State->Header.depth = lsb_16 (&BIH[10]);
State->Compressed = BI_RGB;
} else {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has unsupported header size"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
if (State->Header.depth > 32)
{
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has unsupported depth"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
if (State->Header.size == 12)
clrUsed = 1 << State->Header.depth;
else
clrUsed = (int) (BIH[35] << 24) + (BIH[34] << 16) + (BIH[33] << 8) + (BIH[32]);
if (clrUsed > (1 << State->Header.depth))
{
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has oversize palette"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
if (clrUsed != 0)
State->Header.n_colors = clrUsed;
else
State->Header.n_colors = (1 << State->Header.depth);
State->Type = State->Header.depth; /* This may be less trivial someday */
/* Negative heights indicates bottom-down pixelorder */
if (State->Header.height < 0) {
if (State->Header.height == INT_MIN) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has bogus header data"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
State->Header.height = -State->Header.height;
State->Header.Negative = 1;
}
if (State->Header.Negative &&
(State->Compressed != BI_RGB && State->Compressed != BI_BITFIELDS))
{
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Topdown BMP images cannot be compressed"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
if (State->Header.width <= 0 || State->Header.height == 0 ||
(State->Compressed == BI_RLE4 && State->Type != 4) ||
(State->Compressed == BI_RLE8 && State->Type != 8) ||
(State->Compressed == BI_BITFIELDS && !(State->Type == 16 || State->Type == 32)) ||
(State->Compressed > BI_BITFIELDS)) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has bogus header data"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
if ((State->Type >= 8) && (State->Type <= 32) && (State->Type % 8 == 0)) {
bytesPerPixel = State->Type / 8;
State->LineWidth = State->Header.width * bytesPerPixel;
if (State->Header.width != State->LineWidth / bytesPerPixel) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image width too large"));
return FALSE;
}
} else if (State->Type == 4)
State->LineWidth = (State->Header.width + 1) / 2;
else if (State->Type == 1) {
State->LineWidth = State->Header.width / 8;
if ((State->Header.width & 7) != 0)
State->LineWidth++;
} else {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has bogus header data"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
/* Pad to a 32 bit boundary */
if (((State->LineWidth % 4) > 0)
&& (State->Compressed == BI_RGB || State->Compressed == BI_BITFIELDS))
State->LineWidth = (State->LineWidth / 4) * 4 + 4;
if (State->pixbuf == NULL) {
guint64 len;
int rowstride;
gboolean has_alpha;
if (State->size_func) {
gint width = State->Header.width;
gint height = State->Header.height;
(*State->size_func) (&width, &height, State->user_data);
if (width == 0 || height == 0) {
State->read_state = READ_STATE_DONE;
State->BufferSize = 0;
return TRUE;
}
}
/* rowstride is always >= width, so do an early check for bogus header */
if (State->Header.width <= 0 ||
State->Header.height <= 0 ||
!g_uint64_checked_mul (&len, State->Header.width, State->Header.height) ||
len > G_MAXINT) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has bogus header data"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
if (State->Type == 32 ||
State->Compressed == BI_RLE4 ||
State->Compressed == BI_RLE8)
has_alpha = TRUE;
else
has_alpha = FALSE;
rowstride = gdk_pixbuf_calculate_rowstride (GDK_COLORSPACE_RGB, has_alpha, 8,
(gint) State->Header.width,
(gint) State->Header.height);
if (rowstride <= 0 ||
!g_uint64_checked_mul (&len, rowstride, State->Header.height) ||
len > G_MAXINT) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has bogus header data"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
State->pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, has_alpha, 8,
(gint) State->Header.width,
(gint) State->Header.height);
if (State->pixbuf == NULL) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Not enough memory to load bitmap image"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
if (State->prepared_func != NULL)
/* Notify the client that we are ready to go */
(*State->prepared_func) (State->pixbuf, NULL, State->user_data);
/* make all pixels initially transparent */
if (State->Compressed == BI_RLE4 || State->Compressed == BI_RLE8) {
memset (State->pixbuf->pixels, 0, State->pixbuf->rowstride * State->Header.height);
State->compr.p = State->pixbuf->pixels
+ State->pixbuf->rowstride * (State->Header.height- 1);
}
}
State->BufferDone = 0;
if (State->Type <= 8) {
gint samples;
State->read_state = READ_STATE_PALETTE;
/* Allocate enough to hold the palette */
samples = (State->Header.size == 12 ? 3 : 4);
State->BufferSize = State->Header.n_colors * samples;
/* Skip over everything between the palette and the data.
This protects us against a malicious BFH[10] value.
*/
State->BufferPadding = (lsb_32 (&BFH[10]) - 14 - State->Header.size) - State->BufferSize;
} else if (State->Compressed == BI_RGB) {
if (State->BufferSize < lsb_32 (&BFH[10]))
{
/* skip over padding between headers and image data */
State->read_state = READ_STATE_HEADERS;
State->BufferDone = State->BufferSize;
State->BufferSize = lsb_32 (&BFH[10]);
}
else
{
State->read_state = READ_STATE_DATA;
State->BufferSize = State->LineWidth;
}
} else if (State->Compressed == BI_BITFIELDS) {
if (State->Header.size == 52 || State->Header.size == 56 ||
State->Header.size == 108 || State->Header.size == 124)
{
/* extended v3, v4 and v5 have the bitmasks in the header */
if (!decode_bitmasks (&BIH[40], State, error)) {
State->read_state = READ_STATE_ERROR;
return FALSE;
}
}
else
{
State->read_state = READ_STATE_BITMASKS;
State->BufferSize = 12;
}
} else {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("BMP image has bogus header data"));
State->read_state = READ_STATE_ERROR;
return FALSE;
}
if (!grow_buffer (State, error))
return FALSE;
return TRUE;
}
static gboolean DecodeColormap (guchar *buff,
struct bmp_progressive_state *State,
GError **error)
{
gint i;
gint samples;
guint newbuffersize;
g_assert (State->read_state == READ_STATE_PALETTE);
samples = (State->Header.size == 12 ? 3 : 4);
newbuffersize = State->Header.n_colors * samples;
if (newbuffersize / samples != State->Header.n_colors) /* Integer overflow check */
return FALSE;
if (State->BufferSize < newbuffersize) {
State->BufferSize = newbuffersize;
if (!grow_buffer (State, error))
return FALSE;
return TRUE;
}
State->Colormap = g_malloc0 ((1 << State->Header.depth) * sizeof (*State->Colormap));
for (i = 0; i < State->Header.n_colors; i++)
{
State->Colormap[i][0] = buff[i * samples];
State->Colormap[i][1] = buff[i * samples + 1];
State->Colormap[i][2] = buff[i * samples + 2];
#ifdef DUMPCMAP
g_print ("color %d %x %x %x\n", i,
State->Colormap[i][0],
State->Colormap[i][1],
State->Colormap[i][2]);
#endif
}
State->read_state = READ_STATE_DATA;
State->BufferDone = 0;
if (!(State->Compressed == BI_RGB || State->Compressed == BI_BITFIELDS))
State->BufferSize = 2;
else
State->BufferSize = State->LineWidth;
if (!grow_buffer (State, error))
return FALSE;
return TRUE;
}
/* Finds the lowest set bit and the number of set bits */
static void
find_bits (int n, int *lowest, int *n_set)
{
int i;
*n_set = 0;
for (i = 31; i >= 0; i--)
if (n & (1 << i)) {
*lowest = i;
(*n_set)++;
}
}
/* Decodes the bitmasks for BI_BITFIELDS coding */
static gboolean
decode_bitmasks (guchar *buf,
struct bmp_progressive_state *State,
GError **error)
{
State->a_mask = State->a_shift = State->a_bits = 0;
State->r_mask = buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
buf += 4;
State->g_mask = buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
buf += 4;
State->b_mask = buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
find_bits (State->r_mask, &State->r_shift, &State->r_bits);
find_bits (State->g_mask, &State->g_shift, &State->g_bits);
find_bits (State->b_mask, &State->b_shift, &State->b_bits);
/* extended v3, v4 and v5 have an alpha mask */
if (State->Header.size == 56 || State->Header.size == 108 || State->Header.size == 124) {
buf += 4;
State->a_mask = buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
find_bits (State->a_mask, &State->a_shift, &State->a_bits);
}
if (State->r_bits == 0 || State->g_bits == 0 || State->b_bits == 0) {
if (State->Type == 16) {
State->r_mask = 0x7c00;
State->r_shift = 10;
State->g_mask = 0x03e0;
State->g_shift = 5;
State->b_mask = 0x001f;
State->b_shift = 0;
State->r_bits = State->g_bits = State->b_bits = 5;
}
else {
State->r_mask = 0x00ff0000;
State->r_shift = 16;
State->g_mask = 0x0000ff00;
State->g_shift = 8;
State->b_mask = 0x000000ff;
State->b_shift = 0;
State->a_mask = 0xff000000;
State->a_shift = 24;
State->r_bits = State->g_bits = State->b_bits = State->a_bits = 8;
}
}
if (State->r_bits > 8) {
State->r_shift += State->r_bits - 8;
State->r_bits = 8;
}
if (State->g_bits > 8) {
State->g_shift += State->g_bits - 8;
State->g_bits = 8;
}
if (State->b_bits > 8) {
State->b_shift += State->b_bits - 8;
State->b_bits = 8;
}
if (State->a_bits > 8) {
State->a_shift += State->a_bits - 8;
State->a_bits = 8;
}
State->read_state = READ_STATE_DATA;
State->BufferDone = 0;
State->BufferSize = State->LineWidth;
if (!grow_buffer (State, error))
return FALSE;
return TRUE;
}
/*
* func - called when we have pixmap created (but no image data)
* user_data - passed as arg 1 to func
* return context (opaque to user)
*/
static gpointer
gdk_pixbuf__bmp_image_begin_load(GdkPixbufModuleSizeFunc size_func,
GdkPixbufModulePreparedFunc prepared_func,
GdkPixbufModuleUpdatedFunc updated_func,
gpointer user_data,
GError **error)
{
struct bmp_progressive_state *context;
context = g_new0(struct bmp_progressive_state, 1);
context->size_func = size_func;
context->prepared_func = prepared_func;
context->updated_func = updated_func;
context->user_data = user_data;
context->read_state = READ_STATE_HEADERS;
context->BufferSize = 26;
context->BufferPadding = 0;
context->buff = g_malloc(26);
context->BufferDone = 0;
/* 14 for the BitmapFileHeader, 12 for the BitmapImageHeader */
context->Colormap = NULL;
context->Lines = 0;
context->Type = 0;
memset(&context->Header, 0, sizeof(struct headerpair));
memset(&context->compr, 0, sizeof(struct bmp_compression_state));
context->pixbuf = NULL;
return (gpointer) context;
}
/*
* context - returned from image_begin_load
*
* free context, unref gdk_pixbuf
*/
static gboolean gdk_pixbuf__bmp_image_stop_load(gpointer data, GError **error)
{
gboolean retval = TRUE;
struct bmp_progressive_state *context =
(struct bmp_progressive_state *) data;
/* FIXME this thing needs to report errors if
* we have unused image data
*/
g_return_val_if_fail(context != NULL, TRUE);
g_free(context->Colormap);
if (context->pixbuf)
g_object_unref(context->pixbuf);
if (context->read_state == READ_STATE_HEADERS) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Premature end-of-file encountered"));
retval = FALSE;
}
g_free(context->buff);
g_free(context);
return retval;
}
/*
The OneLineXX functions are called when 1 line worth of data is present.
OneLine24 is the 24 bpp-version.
*/
static void OneLine32(struct bmp_progressive_state *context)
{
int i;
guchar *pixels;
guchar *src;
if (!context->Header.Negative)
pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride * (context->Header.height - context->Lines - 1));
else
pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride * context->Lines);
src = context->buff;
if (context->Compressed == BI_BITFIELDS) {
int r_lshift, r_rshift;
int g_lshift, g_rshift;
int b_lshift, b_rshift;
int a_lshift, a_rshift;
r_lshift = 8 - context->r_bits;
g_lshift = 8 - context->g_bits;
b_lshift = 8 - context->b_bits;
a_lshift = 8 - context->a_bits;
r_rshift = context->r_bits - r_lshift;
g_rshift = context->g_bits - g_lshift;
b_rshift = context->b_bits - b_lshift;
a_rshift = context->a_bits - a_lshift;
for (i = 0; i < context->Header.width; i++) {
unsigned int v, r, g, b, a;
v = src[0] | (src[1] << 8) | (src[2] << 16) | (src[3] << 24);
r = (v & context->r_mask) >> context->r_shift;
g = (v & context->g_mask) >> context->g_shift;
b = (v & context->b_mask) >> context->b_shift;
a = (v & context->a_mask) >> context->a_shift;
*pixels++ = (r << r_lshift) | (r >> r_rshift);
*pixels++ = (g << g_lshift) | (g >> g_rshift);
*pixels++ = (b << b_lshift) | (b >> b_rshift);
if (context->a_bits)
*pixels++ = (a << a_lshift) | (a >> a_rshift);
else
*pixels++ = 0xff;
src += 4;
}
} else
for (i = 0; i < context->Header.width; i++) {
*pixels++ = src[2];
*pixels++ = src[1];
*pixels++ = src[0];
*pixels++ = 0xff;
src += 4;
}
}
static void OneLine24(struct bmp_progressive_state *context)
{
gint X;
guchar *Pixels;
X = 0;
if (context->Header.Negative == 0)
Pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride *
(context->Header.height - context->Lines - 1));
else
Pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride *
context->Lines);
while (X < context->Header.width) {
Pixels[X * 3 + 0] = context->buff[X * 3 + 2];
Pixels[X * 3 + 1] = context->buff[X * 3 + 1];
Pixels[X * 3 + 2] = context->buff[X * 3 + 0];
X++;
}
}
static void OneLine16(struct bmp_progressive_state *context)
{
int i;
guchar *pixels;
guchar *src;
if (!context->Header.Negative)
pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride * (context->Header.height - context->Lines - 1));
else
pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride * context->Lines);
src = context->buff;
if (context->Compressed == BI_BITFIELDS) {
int r_lshift, r_rshift;
int g_lshift, g_rshift;
int b_lshift, b_rshift;
r_lshift = 8 - context->r_bits;
g_lshift = 8 - context->g_bits;
b_lshift = 8 - context->b_bits;
r_rshift = context->r_bits - r_lshift;
g_rshift = context->g_bits - g_lshift;
b_rshift = context->b_bits - b_lshift;
for (i = 0; i < context->Header.width; i++) {
int v, r, g, b;
v = (int) src[0] | ((int) src[1] << 8);
r = (v & context->r_mask) >> context->r_shift;
g = (v & context->g_mask) >> context->g_shift;
b = (v & context->b_mask) >> context->b_shift;
*pixels++ = (r << r_lshift) | (r >> r_rshift);
*pixels++ = (g << g_lshift) | (g >> g_rshift);
*pixels++ = (b << b_lshift) | (b >> b_rshift);
src += 2;
}
} else
for (i = 0; i < context->Header.width; i++) {
int v, r, g, b;
v = src[0] | (src[1] << 8);
r = (v >> 10) & 0x1f;
g = (v >> 5) & 0x1f;
b = v & 0x1f;
*pixels++ = (r << 3) | (r >> 2);
*pixels++ = (g << 3) | (g >> 2);
*pixels++ = (b << 3) | (b >> 2);
src += 2;
}
}
static void OneLine8(struct bmp_progressive_state *context)
{
gint X;
guchar *Pixels;
X = 0;
if (context->Header.Negative == 0)
Pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride *
(context->Header.height - context->Lines - 1));
else
Pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride *
context->Lines);
while (X < context->Header.width) {
Pixels[X * 3 + 0] =
context->Colormap[context->buff[X]][2];
Pixels[X * 3 + 1] =
context->Colormap[context->buff[X]][1];
Pixels[X * 3 + 2] =
context->Colormap[context->buff[X]][0];
X++;
}
}
static void OneLine4(struct bmp_progressive_state *context)
{
gint X;
guchar *Pixels;
X = 0;
if (context->Header.Negative == 0)
Pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride *
(context->Header.height - context->Lines - 1));
else
Pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride *
context->Lines);
while (X < context->Header.width) {
guchar Pix;
Pix = context->buff[X / 2];
Pixels[X * 3 + 0] =
context->Colormap[Pix >> 4][2];
Pixels[X * 3 + 1] =
context->Colormap[Pix >> 4][1];
Pixels[X * 3 + 2] =
context->Colormap[Pix >> 4][0];
X++;
if (X < context->Header.width) {
/* Handle the other 4 bit pixel only when there is one */
Pixels[X * 3 + 0] =
context->Colormap[Pix & 15][2];
Pixels[X * 3 + 1] =
context->Colormap[Pix & 15][1];
Pixels[X * 3 + 2] =
context->Colormap[Pix & 15][0];
X++;
}
}
}
static void OneLine1(struct bmp_progressive_state *context)
{
gint X;
guchar *Pixels;
X = 0;
if (context->Header.Negative == 0)
Pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride *
(context->Header.height - context->Lines - 1));
else
Pixels = (context->pixbuf->pixels +
context->pixbuf->rowstride *
context->Lines);
while (X < context->Header.width) {
gint Bit;
Bit = (context->buff[X / 8]) >> (7 - (X & 7));
Bit = Bit & 1;
Pixels[X * 3 + 0] = context->Colormap[Bit][2];
Pixels[X * 3 + 1] = context->Colormap[Bit][1];
Pixels[X * 3 + 2] = context->Colormap[Bit][0];
X++;
}
}
static void OneLine(struct bmp_progressive_state *context)
{
context->BufferDone = 0;
if (context->Lines >= context->Header.height)
return;
if (context->Type == 32)
OneLine32(context);
else if (context->Type == 24)
OneLine24(context);
else if (context->Type == 16)
OneLine16(context);
else if (context->Type == 8)
OneLine8(context);
else if (context->Type == 4)
OneLine4(context);
else if (context->Type == 1)
OneLine1(context);
else
g_assert_not_reached ();
context->Lines++;
if (context->updated_func != NULL) {
(*context->updated_func) (context->pixbuf,
0,
(context->Header.Negative ?
(context->Lines - 1) :
(context->Header.height - context->Lines)),
context->Header.width,
1,
context->user_data);
}
}
#define NEUTRAL 0
#define ENCODED 1
#define ESCAPE 2
#define DELTA_X 3
#define DELTA_Y 4
#define ABSOLUTE 5
#define SKIP 6
#define END_OF_LINE 0
#define END_OF_BITMAP 1
#define DELTA 2
static gboolean
DoCompressed(struct bmp_progressive_state *context, GError **error)
{
gint i, j;
gint y;
guchar c;
gint idx;
/* context->compr.y might be past the last line because we are
* on padding past the end of a valid data, or we might have hit
* out-of-bounds data. Either way we just eat-and-ignore the
* rest of the file. Doing the check only here and not when
* we change y below is fine since BufferSize is always 2 here
* and the BMP file format always starts new data on 16-bit
* boundaries.
*/
if (context->compr.y >= context->Header.height) {
context->BufferDone = 0;
return TRUE;
}
y = context->compr.y;
for (i = 0; i < context->BufferSize; i++) {
c = context->buff[i];
switch (context->compr.phase) {
case NEUTRAL:
if (c) {
context->compr.run = c;
context->compr.phase = ENCODED;
}
else
context->compr.phase = ESCAPE;
break;
case ENCODED:
for (j = 0; j < context->compr.run; j++) {
if (context->Compressed == BI_RLE8)
idx = c;
else if (j & 1)
idx = c & 0x0f;
else
idx = (c >> 4) & 0x0f;
if (context->compr.x < context->Header.width) {
*context->compr.p++ = context->Colormap[idx][2];
*context->compr.p++ = context->Colormap[idx][1];
*context->compr.p++ = context->Colormap[idx][0];
*context->compr.p++ = 0xff;
context->compr.x++;
}
}
context->compr.phase = NEUTRAL;
break;
case ESCAPE:
switch (c) {
case END_OF_LINE:
context->compr.x = 0;
context->compr.y++;
context->compr.p = context->pixbuf->pixels
+ (context->pixbuf->rowstride * (context->Header.height - context->compr.y - 1))
+ (4 * context->compr.x);
context->compr.phase = NEUTRAL;
break;
case END_OF_BITMAP:
context->compr.x = 0;
context->compr.y = context->Header.height;
context->compr.phase = NEUTRAL;
break;
case DELTA:
context->compr.phase = DELTA_X;
break;
default:
context->compr.run = c;
context->compr.count = 0;
context->compr.phase = ABSOLUTE;
break;
}
break;
case DELTA_X:
context->compr.x += c;
context->compr.phase = DELTA_Y;
break;
case DELTA_Y:
context->compr.y += c;
context->compr.p = context->pixbuf->pixels
+ (context->pixbuf->rowstride * (context->Header.height - context->compr.y - 1))
+ (4 * context->compr.x);
context->compr.phase = NEUTRAL;
break;
case ABSOLUTE:
if (context->Compressed == BI_RLE8) {
idx = c;
if (context->compr.x < context->Header.width) {
*context->compr.p++ = context->Colormap[idx][2];
*context->compr.p++ = context->Colormap[idx][1];
*context->compr.p++ = context->Colormap[idx][0];
*context->compr.p++ = 0xff;
context->compr.x++;
}
context->compr.count++;
if (context->compr.count == context->compr.run) {
if (context->compr.run & 1)
context->compr.phase = SKIP;
else
context->compr.phase = NEUTRAL;
}
}
else {
for (j = 0; j < 2; j++) {
if (context->compr.count & 1)
idx = c & 0x0f;
else
idx = (c >> 4) & 0x0f;
if (context->compr.x < context->Header.width) {
*context->compr.p++ = context->Colormap[idx][2];
*context->compr.p++ = context->Colormap[idx][1];
*context->compr.p++ = context->Colormap[idx][0];
*context->compr.p++ = 0xff;
context->compr.x++;
}
context->compr.count++;
if (context->compr.count == context->compr.run) {
if ((context->compr.run & 3) == 1
|| (context->compr.run & 3) == 2)
context->compr.phase = SKIP;
else
context->compr.phase = NEUTRAL;
break;
}
}
}
break;
case SKIP:
context->compr.phase = NEUTRAL;
break;
}
}
if (context->updated_func != NULL) {
if (context->compr.y > y)
{
gint new_y = MIN (context->compr.y, context->Header.height);
(*context->updated_func) (context->pixbuf,
0,
context->Header.height - new_y,
context->Header.width,
new_y - y,
context->user_data);
}
}
context->BufferDone = 0;
return TRUE;
}
/*
* context - from image_begin_load
* buf - new image data
* size - length of new image data
*
* append image data onto incrementally built output image
*/
static gboolean
gdk_pixbuf__bmp_image_load_increment(gpointer data,
const guchar * buf,
guint size,
GError **error)
{
struct bmp_progressive_state *context =
(struct bmp_progressive_state *) data;
gint BytesToCopy;
gint BytesToRemove;
if (context->read_state == READ_STATE_DONE)
return TRUE;
else if (context->read_state == READ_STATE_ERROR)
return FALSE;
while (size > 0) {
if (context->BufferDone < context->BufferSize) { /* We still
have headerbytes to do */
BytesToCopy =
context->BufferSize - context->BufferDone;
if (BytesToCopy > size)
BytesToCopy = size;
memmove(context->buff + context->BufferDone,
buf, BytesToCopy);
size -= BytesToCopy;
buf += BytesToCopy;
context->BufferDone += BytesToCopy;
if (context->BufferDone != context->BufferSize)
break;
}
/* context->buff is full. Now we discard all "padding" */
if (context->BufferPadding != 0) {
BytesToRemove = context->BufferPadding - size;
if (BytesToRemove > size) {
BytesToRemove = size;
}
size -= BytesToRemove;
context->BufferPadding -= BytesToRemove;
if (context->BufferPadding != 0)
break;
}
switch (context->read_state) {
case READ_STATE_HEADERS:
if (!DecodeHeader (context->buff,
context->buff + 14, context,
error))
return FALSE;
break;
case READ_STATE_PALETTE:
if (!DecodeColormap (context->buff, context, error)) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Error while decoding colormap"));
return FALSE;
}
break;
case READ_STATE_BITMASKS:
if (!decode_bitmasks (context->buff, context, error))
return FALSE;
break;
case READ_STATE_DATA:
if (context->Compressed == BI_RGB || context->Compressed == BI_BITFIELDS)
OneLine (context);
else if (!DoCompressed (context, error))
return FALSE;
break;
case READ_STATE_DONE:
return TRUE;
break;
default:
g_assert_not_reached ();
}
}
return TRUE;
}
/* for our convenience when filling file header */
#define put16(buf,data) { guint16 x; \
x = GUINT16_TO_LE (data); \
memcpy(buf, &x, 2); \
buf += 2; }
#define put32(buf,data) { guint32 x; \
x = GUINT32_TO_LE (data); \
memcpy(buf, &x, 4); \
buf += 4; }
static gboolean
gdk_pixbuf__bmp_image_save_to_callback (GdkPixbufSaveFunc save_func,
gpointer user_data,
GdkPixbuf *pixbuf,
gchar **keys,
gchar **values,
GError **error)
{
guint width, height, channel, size, stride, src_stride, x, y;
guint bf_size;
guchar BFH_BIH[54], *pixels, *buf, *src, *dst, *dst_line;
gboolean ret;
width = gdk_pixbuf_get_width (pixbuf);
height = gdk_pixbuf_get_height (pixbuf);
channel = gdk_pixbuf_get_n_channels (pixbuf);
pixels = gdk_pixbuf_get_pixels (pixbuf);
src_stride = gdk_pixbuf_get_rowstride (pixbuf);
/* stride = (width * 3 + 3) & ~3 */
if (!g_uint_checked_mul (&stride, width, 3) ||
!g_uint_checked_add (&stride, stride, 3)) {
g_set_error_literal (error, GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_FAILED,
_("Image is too wide for BMP format."));
return FALSE;
}
stride &= ~3;
/* size = stride * height
* bf_size = size + 14 + 40 */
if (!g_uint_checked_mul (&size, stride, height) ||
!g_uint_checked_add (&bf_size, size, 14 + 40)) {
g_set_error_literal (error, GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_FAILED,
_("Image is too wide for BMP format."));
return FALSE;
}
/* filling BFH */
dst = BFH_BIH;
*dst++ = 'B'; /* bfType */
*dst++ = 'M';
put32 (dst, bf_size); /* bfSize */
put32 (dst, 0); /* bfReserved1 + bfReserved2 */
put32 (dst, 14 + 40); /* bfOffBits */
/* filling BIH */
put32 (dst, 40); /* biSize */
put32 (dst, width); /* biWidth */
put32 (dst, height); /* biHeight */
put16 (dst, 1); /* biPlanes */
put16 (dst, 24); /* biBitCount */
put32 (dst, BI_RGB); /* biCompression */
put32 (dst, size); /* biSizeImage */
put32 (dst, 0); /* biXPelsPerMeter */
put32 (dst, 0); /* biYPelsPerMeter */
put32 (dst, 0); /* biClrUsed */
put32 (dst, 0); /* biClrImportant */
if (!save_func ((gchar *)BFH_BIH, 14 + 40, error, user_data))
return FALSE;
dst_line = buf = g_try_malloc (size);
if (!buf) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Couldn't allocate memory for saving BMP file"));
return FALSE;
}
/* saving as a bottom-up bmp */
pixels += (height - 1) * src_stride;
for (y = 0; y < height; ++y, pixels -= src_stride, dst_line += stride) {
dst = dst_line;
src = pixels;
for (x = 0; x < width; ++x, dst += 3, src += channel) {
dst[0] = src[2];
dst[1] = src[1];
dst[2] = src[0];
}
}
ret = save_func ((gchar *)buf, size, error, user_data);
g_free (buf);
return ret;
}
static gboolean
save_to_file_cb (const gchar *buf,
gsize count,
GError **error,
gpointer data)
{
gint bytes;
while (count > 0) {
bytes = fwrite (buf, sizeof (gchar), count, (FILE *) data);
if (bytes <= 0)
break;
count -= bytes;
buf += bytes;
}
if (count) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_FAILED,
_("Couldn't write to BMP file"));
return FALSE;
}
return TRUE;
}
static gboolean
gdk_pixbuf__bmp_image_save (FILE *f,
GdkPixbuf *pixbuf,
gchar **keys,
gchar **values,
GError **error)
{
return gdk_pixbuf__bmp_image_save_to_callback (save_to_file_cb,
f, pixbuf, keys,
values, error);
}
#ifndef INCLUDE_bmp
#define MODULE_ENTRY(function) G_MODULE_EXPORT void function
#else
#define MODULE_ENTRY(function) void _gdk_pixbuf__bmp_ ## function
#endif
MODULE_ENTRY (fill_vtable) (GdkPixbufModule *module)
{
module->begin_load = gdk_pixbuf__bmp_image_begin_load;
module->stop_load = gdk_pixbuf__bmp_image_stop_load;
module->load_increment = gdk_pixbuf__bmp_image_load_increment;
module->save = gdk_pixbuf__bmp_image_save;
module->save_to_callback = gdk_pixbuf__bmp_image_save_to_callback;
}
MODULE_ENTRY (fill_info) (GdkPixbufFormat *info)
{
static const GdkPixbufModulePattern signature[] = {
{ "BM", NULL, 100 },
{ NULL, NULL, 0 }
};
static const gchar * mime_types[] = {
"image/bmp",
"image/x-bmp",
"image/x-MS-bmp",
NULL
};
static const gchar * extensions[] = {
"bmp",
NULL
};
info->name = "bmp";
info->signature = (GdkPixbufModulePattern *) signature;
info->description = NC_("image format", "BMP");
info->mime_types = (gchar **) mime_types;
info->extensions = (gchar **) extensions;
info->flags = GDK_PIXBUF_FORMAT_WRITABLE | GDK_PIXBUF_FORMAT_THREADSAFE;
info->license = "LGPL";
}