gtk2/gdk-pixbuf/io-jpeg.c
Matthias Clasen 044f168507 Set scale_num only once
This modifies the previous commit to be according the upstream libjpeg
maintainers recommendations. See bug 588740.
2009-11-25 23:39:31 -05:00

1316 lines
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/* -*- mode: C; c-file-style: "linux" -*- */
/* GdkPixbuf library - JPEG image loader
*
* Copyright (C) 1999 Michael Zucchi
* Copyright (C) 1999 The Free Software Foundation
*
* Progressive loading code Copyright (C) 1999 Red Hat, Inc.
*
* Authors: Michael Zucchi <zucchi@zedzone.mmc.com.au>
* Federico Mena-Quintero <federico@gimp.org>
* Michael Fulbright <drmike@redhat.com>
*
* 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, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <setjmp.h>
#include <jpeglib.h>
#include <jerror.h>
#include "gdk-pixbuf-private.h"
#include "gdk-pixbuf-io.h"
#ifndef HAVE_SIGSETJMP
#define sigjmp_buf jmp_buf
#define sigsetjmp(jb, x) setjmp(jb)
#define siglongjmp longjmp
#endif
/* we are a "source manager" as far as libjpeg is concerned */
#define JPEG_PROG_BUF_SIZE 65536
typedef struct {
struct jpeg_source_mgr pub; /* public fields */
JOCTET buffer[JPEG_PROG_BUF_SIZE]; /* start of buffer */
long skip_next; /* number of bytes to skip next read */
} my_source_mgr;
typedef my_source_mgr * my_src_ptr;
/* error handler data */
struct error_handler_data {
struct jpeg_error_mgr pub;
sigjmp_buf setjmp_buffer;
GError **error;
};
/* progressive loader context */
typedef struct {
GdkPixbufModuleSizeFunc size_func;
GdkPixbufModuleUpdatedFunc updated_func;
GdkPixbufModulePreparedFunc prepared_func;
gpointer user_data;
GdkPixbuf *pixbuf;
guchar *dptr; /* current position in pixbuf */
gboolean did_prescan; /* are we in image data yet? */
gboolean got_header; /* have we loaded jpeg header? */
gboolean src_initialized;/* TRUE when jpeg lib initialized */
gboolean in_output; /* did we get suspended in an output pass? */
struct jpeg_decompress_struct cinfo;
struct error_handler_data jerr;
} JpegProgContext;
static GdkPixbuf *gdk_pixbuf__jpeg_image_load (FILE *f, GError **error);
static gpointer gdk_pixbuf__jpeg_image_begin_load (GdkPixbufModuleSizeFunc func0,
GdkPixbufModulePreparedFunc func1,
GdkPixbufModuleUpdatedFunc func2,
gpointer user_data,
GError **error);
static gboolean gdk_pixbuf__jpeg_image_stop_load (gpointer context, GError **error);
static gboolean gdk_pixbuf__jpeg_image_load_increment(gpointer context,
const guchar *buf, guint size,
GError **error);
static void
fatal_error_handler (j_common_ptr cinfo)
{
struct error_handler_data *errmgr;
char buffer[JMSG_LENGTH_MAX];
errmgr = (struct error_handler_data *) cinfo->err;
/* Create the message */
(* cinfo->err->format_message) (cinfo, buffer);
/* broken check for *error == NULL for robustness against
* crappy JPEG library
*/
if (errmgr->error && *errmgr->error == NULL) {
g_set_error (errmgr->error,
GDK_PIXBUF_ERROR,
cinfo->err->msg_code == JERR_OUT_OF_MEMORY
? GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY
: GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Error interpreting JPEG image file (%s)"),
buffer);
}
siglongjmp (errmgr->setjmp_buffer, 1);
g_assert_not_reached ();
}
static void
output_message_handler (j_common_ptr cinfo)
{
/* This method keeps libjpeg from dumping crap to stderr */
/* do nothing */
}
/* explode gray image data from jpeg library into rgb components in pixbuf */
static void
explode_gray_into_buf (struct jpeg_decompress_struct *cinfo,
guchar **lines)
{
gint i, j;
guint w;
g_return_if_fail (cinfo != NULL);
g_return_if_fail (cinfo->output_components == 1);
g_return_if_fail (cinfo->out_color_space == JCS_GRAYSCALE);
/* Expand grey->colour. Expand from the end of the
* memory down, so we can use the same buffer.
*/
w = cinfo->output_width;
for (i = cinfo->rec_outbuf_height - 1; i >= 0; i--) {
guchar *from, *to;
from = lines[i] + w - 1;
to = lines[i] + (w - 1) * 3;
for (j = w - 1; j >= 0; j--) {
to[0] = from[0];
to[1] = from[0];
to[2] = from[0];
to -= 3;
from--;
}
}
}
static void
convert_cmyk_to_rgb (struct jpeg_decompress_struct *cinfo,
guchar **lines)
{
gint i, j;
g_return_if_fail (cinfo != NULL);
g_return_if_fail (cinfo->output_components == 4);
g_return_if_fail (cinfo->out_color_space == JCS_CMYK);
for (i = cinfo->rec_outbuf_height - 1; i >= 0; i--) {
guchar *p;
p = lines[i];
for (j = 0; j < cinfo->output_width; j++) {
int c, m, y, k;
c = p[0];
m = p[1];
y = p[2];
k = p[3];
if (cinfo->saw_Adobe_marker) {
p[0] = k*c / 255;
p[1] = k*m / 255;
p[2] = k*y / 255;
}
else {
p[0] = (255 - k)*(255 - c) / 255;
p[1] = (255 - k)*(255 - m) / 255;
p[2] = (255 - k)*(255 - y) / 255;
}
p[3] = 255;
p += 4;
}
}
}
typedef struct {
struct jpeg_source_mgr pub; /* public fields */
FILE * infile; /* source stream */
JOCTET * buffer; /* start of buffer */
boolean start_of_file; /* have we gotten any data yet? */
} stdio_source_mgr;
typedef stdio_source_mgr * stdio_src_ptr;
static void
stdio_init_source (j_decompress_ptr cinfo)
{
stdio_src_ptr src = (stdio_src_ptr)cinfo->src;
src->start_of_file = FALSE;
}
static boolean
stdio_fill_input_buffer (j_decompress_ptr cinfo)
{
stdio_src_ptr src = (stdio_src_ptr) cinfo->src;
size_t nbytes;
nbytes = fread (src->buffer, 1, JPEG_PROG_BUF_SIZE, src->infile);
if (nbytes <= 0) {
#if 0
if (src->start_of_file) /* Treat empty input file as fatal error */
ERREXIT(cinfo, JERR_INPUT_EMPTY);
WARNMS(cinfo, JWRN_JPEG_EOF);
#endif
/* Insert a fake EOI marker */
src->buffer[0] = (JOCTET) 0xFF;
src->buffer[1] = (JOCTET) JPEG_EOI;
nbytes = 2;
}
src->pub.next_input_byte = src->buffer;
src->pub.bytes_in_buffer = nbytes;
src->start_of_file = FALSE;
return TRUE;
}
static void
stdio_skip_input_data (j_decompress_ptr cinfo, long num_bytes)
{
stdio_src_ptr src = (stdio_src_ptr) cinfo->src;
if (num_bytes > 0) {
while (num_bytes > (long) src->pub.bytes_in_buffer) {
num_bytes -= (long) src->pub.bytes_in_buffer;
(void)stdio_fill_input_buffer(cinfo);
}
src->pub.next_input_byte += (size_t) num_bytes;
src->pub.bytes_in_buffer -= (size_t) num_bytes;
}
}
static void
stdio_term_source (j_decompress_ptr cinfo)
{
}
static gchar *
colorspace_name (const J_COLOR_SPACE jpeg_color_space)
{
switch (jpeg_color_space) {
case JCS_UNKNOWN: return "UNKNOWN";
case JCS_GRAYSCALE: return "GRAYSCALE";
case JCS_RGB: return "RGB";
case JCS_YCbCr: return "YCbCr";
case JCS_CMYK: return "CMYK";
case JCS_YCCK: return "YCCK";
default: return "invalid";
}
}
const char leth[] = {0x49, 0x49, 0x2a, 0x00}; // Little endian TIFF header
const char beth[] = {0x4d, 0x4d, 0x00, 0x2a}; // Big endian TIFF header
const char types[] = {0x00, 0x01, 0x01, 0x02, 0x04, 0x08, 0x00,
0x08, 0x00, 0x04, 0x08}; // size in bytes for EXIF types
#define DE_ENDIAN16(val) endian == G_BIG_ENDIAN ? GUINT16_FROM_BE(val) : GUINT16_FROM_LE(val)
#define DE_ENDIAN32(val) endian == G_BIG_ENDIAN ? GUINT32_FROM_BE(val) : GUINT32_FROM_LE(val)
#define ENDIAN16_IT(val) endian == G_BIG_ENDIAN ? GUINT16_TO_BE(val) : GUINT16_TO_LE(val)
#define ENDIAN32_IT(val) endian == G_BIG_ENDIAN ? GUINT32_TO_BE(val) : GUINT32_TO_LE(val)
#define EXIF_JPEG_MARKER JPEG_APP0+1
#define EXIF_IDENT_STRING "Exif\000\000"
static unsigned short de_get16(void *ptr, guint endian)
{
unsigned short val;
memcpy(&val, ptr, sizeof(val));
val = DE_ENDIAN16(val);
return val;
}
static unsigned int de_get32(void *ptr, guint endian)
{
unsigned int val;
memcpy(&val, ptr, sizeof(val));
val = DE_ENDIAN32(val);
return val;
}
static gint
get_orientation (j_decompress_ptr cinfo)
{
/* This function looks through the meta data in the libjpeg decompress structure to
determine if an EXIF Orientation tag is present and if so return its value (1-8).
If no EXIF Orientation tag is found 0 (zero) is returned. */
guint i; /* index into working buffer */
guint orient_tag_id; /* endianed version of orientation tag ID */
guint ret; /* Return value */
guint offset; /* de-endianed offset in various situations */
guint tags; /* number of tags in current ifd */
guint type; /* de-endianed type of tag used as index into types[] */
guint count; /* de-endianed count of elements in a tag */
guint tiff = 0; /* offset to active tiff header */
guint endian = 0; /* detected endian of data */
jpeg_saved_marker_ptr exif_marker; /* Location of the Exif APP1 marker */
jpeg_saved_marker_ptr cmarker; /* Location to check for Exif APP1 marker */
/* check for Exif marker (also called the APP1 marker) */
exif_marker = NULL;
cmarker = cinfo->marker_list;
while (cmarker) {
if (cmarker->marker == EXIF_JPEG_MARKER) {
/* The Exif APP1 marker should contain a unique
identification string ("Exif\0\0"). Check for it. */
if (!memcmp (cmarker->data, EXIF_IDENT_STRING, 6)) {
exif_marker = cmarker;
}
}
cmarker = cmarker->next;
}
/* Did we find the Exif APP1 marker? */
if (exif_marker == NULL)
return 0;
/* Do we have enough data? */
if (exif_marker->data_length < 32)
return 0;
/* Check for TIFF header and catch endianess */
i = 0;
/* Just skip data until TIFF header - it should be within 16 bytes from marker start.
Normal structure relative to APP1 marker -
0x0000: APP1 marker entry = 2 bytes
0x0002: APP1 length entry = 2 bytes
0x0004: Exif Identifier entry = 6 bytes
0x000A: Start of TIFF header (Byte order entry) - 4 bytes
- This is what we look for, to determine endianess.
0x000E: 0th IFD offset pointer - 4 bytes
exif_marker->data points to the first data after the APP1 marker
and length entries, which is the exif identification string.
The TIFF header should thus normally be found at i=6, below,
and the pointer to IFD0 will be at 6+4 = 10.
*/
while (i < 16) {
/* Little endian TIFF header */
if (memcmp (&exif_marker->data[i], leth, 4) == 0){
endian = G_LITTLE_ENDIAN;
}
/* Big endian TIFF header */
else if (memcmp (&exif_marker->data[i], beth, 4) == 0){
endian = G_BIG_ENDIAN;
}
/* Keep looking through buffer */
else {
i++;
continue;
}
/* We have found either big or little endian TIFF header */
tiff = i;
break;
}
/* So did we find a TIFF header or did we just hit end of buffer? */
if (tiff == 0)
return 0;
/* Endian the orientation tag ID, to locate it more easily */
orient_tag_id = ENDIAN16_IT(0x112);
/* Read out the offset pointer to IFD0 */
offset = de_get32(&exif_marker->data[i] + 4, endian);
i = i + offset;
/* Check that we still are within the buffer and can read the tag count */
if ((i + 2) > exif_marker->data_length)
return 0;
/* Find out how many tags we have in IFD0. As per the TIFF spec, the first
two bytes of the IFD contain a count of the number of tags. */
tags = de_get16(&exif_marker->data[i], endian);
i = i + 2;
/* Check that we still have enough data for all tags to check. The tags
are listed in consecutive 12-byte blocks. The tag ID, type, size, and
a pointer to the actual value, are packed into these 12 byte entries. */
if ((i + tags * 12) > exif_marker->data_length)
return 0;
/* Check through IFD0 for tags of interest */
while (tags--){
type = de_get16(&exif_marker->data[i + 2], endian);
count = de_get32(&exif_marker->data[i + 4], endian);
/* Is this the orientation tag? */
if (memcmp (&exif_marker->data[i], (char *) &orient_tag_id, 2) == 0){
/* Check that type and count fields are OK. The orientation field
will consist of a single (count=1) 2-byte integer (type=3). */
if (type != 3 || count != 1) return 0;
/* Return the orientation value. Within the 12-byte block, the
pointer to the actual data is at offset 8. */
ret = de_get16(&exif_marker->data[i + 8], endian);
return ret <= 8 ? ret : 0;
}
/* move the pointer to the next 12-byte tag field. */
i = i + 12;
}
return 0; /* No EXIF Orientation tag found */
}
/* Shared library entry point */
static GdkPixbuf *
gdk_pixbuf__jpeg_image_load (FILE *f, GError **error)
{
gint i;
int is_otag;
char otag_str[5];
GdkPixbuf * volatile pixbuf = NULL;
guchar *dptr;
guchar *lines[4]; /* Used to expand rows, via rec_outbuf_height,
* from the header file:
* " Usually rec_outbuf_height will be 1 or 2,
* at most 4."
*/
guchar **lptr;
struct jpeg_decompress_struct cinfo;
struct error_handler_data jerr;
stdio_src_ptr src;
/* setup error handler */
cinfo.err = jpeg_std_error (&jerr.pub);
jerr.pub.error_exit = fatal_error_handler;
jerr.pub.output_message = output_message_handler;
jerr.error = error;
if (sigsetjmp (jerr.setjmp_buffer, 1)) {
/* Whoops there was a jpeg error */
if (pixbuf)
g_object_unref (pixbuf);
jpeg_destroy_decompress (&cinfo);
/* error should have been set by fatal_error_handler () */
return NULL;
}
/* load header, setup */
jpeg_create_decompress (&cinfo);
cinfo.src = (struct jpeg_source_mgr *)
(*cinfo.mem->alloc_small) ((j_common_ptr) &cinfo, JPOOL_PERMANENT,
sizeof (stdio_source_mgr));
src = (stdio_src_ptr) cinfo.src;
src->buffer = (JOCTET *)
(*cinfo.mem->alloc_small) ((j_common_ptr) &cinfo, JPOOL_PERMANENT,
JPEG_PROG_BUF_SIZE * sizeof (JOCTET));
src->pub.init_source = stdio_init_source;
src->pub.fill_input_buffer = stdio_fill_input_buffer;
src->pub.skip_input_data = stdio_skip_input_data;
src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */
src->pub.term_source = stdio_term_source;
src->infile = f;
src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */
src->pub.next_input_byte = NULL; /* until buffer loaded */
jpeg_save_markers (&cinfo, EXIF_JPEG_MARKER, 0xffff);
jpeg_read_header (&cinfo, TRUE);
/* check for orientation tag */
is_otag = get_orientation (&cinfo);
jpeg_start_decompress (&cinfo);
cinfo.do_fancy_upsampling = FALSE;
cinfo.do_block_smoothing = FALSE;
pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB,
cinfo.out_color_components == 4 ? TRUE : FALSE,
8, cinfo.output_width, cinfo.output_height);
if (!pixbuf) {
jpeg_destroy_decompress (&cinfo);
/* broken check for *error == NULL for robustness against
* crappy JPEG library
*/
if (error && *error == NULL) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Insufficient memory to load image, try exiting some applications to free memory"));
}
return NULL;
}
/* if orientation tag was found set an option to remember its value */
if (is_otag) {
g_snprintf (otag_str, sizeof (otag_str), "%d", is_otag);
gdk_pixbuf_set_option (pixbuf, "orientation", otag_str);
}
dptr = pixbuf->pixels;
/* decompress all the lines, a few at a time */
while (cinfo.output_scanline < cinfo.output_height) {
lptr = lines;
for (i = 0; i < cinfo.rec_outbuf_height; i++) {
*lptr++ = dptr;
dptr += pixbuf->rowstride;
}
jpeg_read_scanlines (&cinfo, lines, cinfo.rec_outbuf_height);
switch (cinfo.out_color_space) {
case JCS_GRAYSCALE:
explode_gray_into_buf (&cinfo, lines);
break;
case JCS_RGB:
/* do nothing */
break;
case JCS_CMYK:
convert_cmyk_to_rgb (&cinfo, lines);
break;
default:
g_object_unref (pixbuf);
if (error && *error == NULL) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_UNKNOWN_TYPE,
_("Unsupported JPEG color space (%s)"),
colorspace_name (cinfo.out_color_space));
}
jpeg_destroy_decompress (&cinfo);
return NULL;
}
}
jpeg_finish_decompress (&cinfo);
jpeg_destroy_decompress (&cinfo);
return pixbuf;
}
/**** Progressive image loading handling *****/
/* these routines required because we are acting as a source manager for */
/* libjpeg. */
static void
init_source (j_decompress_ptr cinfo)
{
my_src_ptr src = (my_src_ptr) cinfo->src;
src->skip_next = 0;
}
static void
term_source (j_decompress_ptr cinfo)
{
/* XXXX - probably should scream something has happened */
}
/* for progressive loading (called "I/O Suspension" by libjpeg docs) */
/* we do nothing except return "FALSE" */
static boolean
fill_input_buffer (j_decompress_ptr cinfo)
{
return FALSE;
}
static void
skip_input_data (j_decompress_ptr cinfo, long num_bytes)
{
my_src_ptr src = (my_src_ptr) cinfo->src;
long num_can_do;
/* move as far as we can into current buffer */
/* then set skip_next to catch the rest */
if (num_bytes > 0) {
num_can_do = MIN (src->pub.bytes_in_buffer, num_bytes);
src->pub.next_input_byte += (size_t) num_can_do;
src->pub.bytes_in_buffer -= (size_t) num_can_do;
src->skip_next = num_bytes - num_can_do;
}
}
/*
* 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__jpeg_image_begin_load (GdkPixbufModuleSizeFunc size_func,
GdkPixbufModulePreparedFunc prepared_func,
GdkPixbufModuleUpdatedFunc updated_func,
gpointer user_data,
GError **error)
{
JpegProgContext *context;
my_source_mgr *src;
context = g_new0 (JpegProgContext, 1);
context->size_func = size_func;
context->prepared_func = prepared_func;
context->updated_func = updated_func;
context->user_data = user_data;
context->pixbuf = NULL;
context->got_header = FALSE;
context->did_prescan = FALSE;
context->src_initialized = FALSE;
context->in_output = FALSE;
/* create libjpeg structures */
jpeg_create_decompress (&context->cinfo);
context->cinfo.src = (struct jpeg_source_mgr *) g_try_malloc (sizeof (my_source_mgr));
if (!context->cinfo.src) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Couldn't allocate memory for loading JPEG file"));
return NULL;
}
memset (context->cinfo.src, 0, sizeof (my_source_mgr));
src = (my_src_ptr) context->cinfo.src;
context->cinfo.err = jpeg_std_error (&context->jerr.pub);
context->jerr.pub.error_exit = fatal_error_handler;
context->jerr.pub.output_message = output_message_handler;
context->jerr.error = error;
src = (my_src_ptr) context->cinfo.src;
src->pub.init_source = init_source;
src->pub.fill_input_buffer = fill_input_buffer;
src->pub.skip_input_data = skip_input_data;
src->pub.resync_to_restart = jpeg_resync_to_restart;
src->pub.term_source = term_source;
src->pub.bytes_in_buffer = 0;
src->pub.next_input_byte = NULL;
context->jerr.error = NULL;
return (gpointer) context;
}
/*
* context - returned from image_begin_load
*
* free context, unref gdk_pixbuf
*/
static gboolean
gdk_pixbuf__jpeg_image_stop_load (gpointer data, GError **error)
{
JpegProgContext *context = (JpegProgContext *) data;
gboolean retval;
g_return_val_if_fail (context != NULL, TRUE);
/* FIXME this thing needs to report errors if
* we have unused image data
*/
if (context->pixbuf)
g_object_unref (context->pixbuf);
/* if we have an error? */
context->jerr.error = error;
if (sigsetjmp (context->jerr.setjmp_buffer, 1)) {
retval = FALSE;
} else {
jpeg_finish_decompress (&context->cinfo);
retval = TRUE;
}
jpeg_destroy_decompress (&context->cinfo);
if (context->cinfo.src) {
my_src_ptr src = (my_src_ptr) context->cinfo.src;
g_free (src);
}
g_free (context);
return retval;
}
static gboolean
gdk_pixbuf__jpeg_image_load_lines (JpegProgContext *context,
GError **error)
{
struct jpeg_decompress_struct *cinfo = &context->cinfo;
guchar *lines[4];
guchar **lptr;
guchar *rowptr;
gint nlines, i;
/* keep going until we've done all scanlines */
while (cinfo->output_scanline < cinfo->output_height) {
lptr = lines;
rowptr = context->dptr;
for (i=0; i < cinfo->rec_outbuf_height; i++) {
*lptr++ = rowptr;
rowptr += context->pixbuf->rowstride;
}
nlines = jpeg_read_scanlines (cinfo, lines,
cinfo->rec_outbuf_height);
if (nlines == 0)
break;
switch (cinfo->out_color_space) {
case JCS_GRAYSCALE:
explode_gray_into_buf (cinfo, lines);
break;
case JCS_RGB:
/* do nothing */
break;
case JCS_CMYK:
convert_cmyk_to_rgb (cinfo, lines);
break;
default:
if (error && *error == NULL) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_UNKNOWN_TYPE,
_("Unsupported JPEG color space (%s)"),
colorspace_name (cinfo->out_color_space));
}
return FALSE;
}
context->dptr += nlines * context->pixbuf->rowstride;
/* send updated signal */
if (context->updated_func)
(* context->updated_func) (context->pixbuf,
0,
cinfo->output_scanline - 1,
cinfo->image_width,
nlines,
context->user_data);
}
return TRUE;
}
/*
* context - from image_begin_load
* buf - new image data
* size - length of new image data
*
* append image data onto inrecrementally built output image
*/
static gboolean
gdk_pixbuf__jpeg_image_load_increment (gpointer data,
const guchar *buf, guint size,
GError **error)
{
JpegProgContext *context = (JpegProgContext *)data;
struct jpeg_decompress_struct *cinfo;
my_src_ptr src;
guint num_left, num_copy;
guint last_num_left, last_bytes_left;
guint spinguard;
gboolean first;
const guchar *bufhd;
gint width, height;
int is_otag;
char otag_str[5];
g_return_val_if_fail (context != NULL, FALSE);
g_return_val_if_fail (buf != NULL, FALSE);
src = (my_src_ptr) context->cinfo.src;
cinfo = &context->cinfo;
context->jerr.error = error;
/* check for fatal error */
if (sigsetjmp (context->jerr.setjmp_buffer, 1)) {
return FALSE;
}
/* skip over data if requested, handle unsigned int sizes cleanly */
/* only can happen if we've already called jpeg_get_header once */
if (context->src_initialized && src->skip_next) {
if (src->skip_next > size) {
src->skip_next -= size;
return TRUE;
} else {
num_left = size - src->skip_next;
bufhd = buf + src->skip_next;
src->skip_next = 0;
}
} else {
num_left = size;
bufhd = buf;
}
if (num_left == 0)
return TRUE;
last_num_left = num_left;
last_bytes_left = 0;
spinguard = 0;
first = TRUE;
while (TRUE) {
/* handle any data from caller we haven't processed yet */
if (num_left > 0) {
if(src->pub.bytes_in_buffer &&
src->pub.next_input_byte != src->buffer)
memmove(src->buffer, src->pub.next_input_byte,
src->pub.bytes_in_buffer);
num_copy = MIN (JPEG_PROG_BUF_SIZE - src->pub.bytes_in_buffer,
num_left);
memcpy(src->buffer + src->pub.bytes_in_buffer, bufhd,num_copy);
src->pub.next_input_byte = src->buffer;
src->pub.bytes_in_buffer += num_copy;
bufhd += num_copy;
num_left -= num_copy;
}
/* did anything change from last pass, if not return */
if (first) {
last_bytes_left = src->pub.bytes_in_buffer;
first = FALSE;
} else if (src->pub.bytes_in_buffer == last_bytes_left
&& num_left == last_num_left) {
spinguard++;
} else {
last_bytes_left = src->pub.bytes_in_buffer;
last_num_left = num_left;
}
/* should not go through twice and not pull bytes out of buf */
if (spinguard > 2)
return TRUE;
/* try to load jpeg header */
if (!context->got_header) {
int rc;
jpeg_save_markers (cinfo, EXIF_JPEG_MARKER, 0xffff);
rc = jpeg_read_header (cinfo, TRUE);
context->src_initialized = TRUE;
if (rc == JPEG_SUSPENDED)
continue;
context->got_header = TRUE;
/* check for orientation tag */
is_otag = get_orientation (cinfo);
width = cinfo->image_width;
height = cinfo->image_height;
if (context->size_func) {
(* context->size_func) (&width, &height, context->user_data);
if (width == 0 || height == 0) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
_("Transformed JPEG has zero width or height."));
return FALSE;
}
}
cinfo->scale_num = 1;
for (cinfo->scale_denom = 2; cinfo->scale_denom <= 8; cinfo->scale_denom *= 2) {
jpeg_calc_output_dimensions (cinfo);
if (cinfo->output_width < width || cinfo->output_height < height) {
cinfo->scale_denom /= 2;
break;
}
}
jpeg_calc_output_dimensions (cinfo);
context->pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB,
cinfo->output_components == 4 ? TRUE : FALSE,
8,
cinfo->output_width,
cinfo->output_height);
if (context->pixbuf == NULL) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Couldn't allocate memory for loading JPEG file"));
return FALSE;
}
/* if orientation tag was found set an option to remember its value */
if (is_otag) {
g_snprintf (otag_str, sizeof (otag_str), "%d", is_otag);
gdk_pixbuf_set_option (context->pixbuf, "orientation", otag_str);
}
/* Use pixbuf buffer to store decompressed data */
context->dptr = context->pixbuf->pixels;
/* Notify the client that we are ready to go */
if (context->prepared_func)
(* context->prepared_func) (context->pixbuf,
NULL,
context->user_data);
} else if (!context->did_prescan) {
int rc;
/* start decompression */
cinfo->buffered_image = cinfo->progressive_mode;
rc = jpeg_start_decompress (cinfo);
cinfo->do_fancy_upsampling = FALSE;
cinfo->do_block_smoothing = FALSE;
if (rc == JPEG_SUSPENDED)
continue;
context->did_prescan = TRUE;
} else if (!cinfo->buffered_image) {
/* we're decompressing unbuffered so
* simply get scanline by scanline from jpeg lib
*/
if (! gdk_pixbuf__jpeg_image_load_lines (context,
error))
return FALSE;
if (cinfo->output_scanline >= cinfo->output_height)
return TRUE;
} else {
/* we're decompressing buffered (progressive)
* so feed jpeg lib scanlines
*/
/* keep going until we've done all passes */
while (!jpeg_input_complete (cinfo)) {
if (!context->in_output) {
if (jpeg_start_output (cinfo, cinfo->input_scan_number)) {
context->in_output = TRUE;
context->dptr = context->pixbuf->pixels;
}
else
break;
}
/* get scanlines from jpeg lib */
if (! gdk_pixbuf__jpeg_image_load_lines (context,
error))
return FALSE;
if (cinfo->output_scanline >= cinfo->output_height &&
jpeg_finish_output (cinfo))
context->in_output = FALSE;
else
break;
}
if (jpeg_input_complete (cinfo))
/* did entire image */
return TRUE;
else
continue;
}
}
}
/* Save */
#define TO_FUNCTION_BUF_SIZE 4096
typedef struct {
struct jpeg_destination_mgr pub;
JOCTET *buffer;
GdkPixbufSaveFunc save_func;
gpointer user_data;
GError **error;
} ToFunctionDestinationManager;
void
to_callback_init (j_compress_ptr cinfo)
{
ToFunctionDestinationManager *destmgr;
destmgr = (ToFunctionDestinationManager*) cinfo->dest;
destmgr->pub.next_output_byte = destmgr->buffer;
destmgr->pub.free_in_buffer = TO_FUNCTION_BUF_SIZE;
}
static void
to_callback_do_write (j_compress_ptr cinfo, gsize length)
{
ToFunctionDestinationManager *destmgr;
destmgr = (ToFunctionDestinationManager*) cinfo->dest;
if (!destmgr->save_func ((gchar *)destmgr->buffer,
length,
destmgr->error,
destmgr->user_data)) {
struct error_handler_data *errmgr;
errmgr = (struct error_handler_data *) cinfo->err;
/* Use a default error message if the callback didn't set one,
* which it should have.
*/
if (errmgr->error && *errmgr->error == NULL) {
g_set_error_literal (errmgr->error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_CORRUPT_IMAGE,
"write function failed");
}
siglongjmp (errmgr->setjmp_buffer, 1);
g_assert_not_reached ();
}
}
static boolean
to_callback_empty_output_buffer (j_compress_ptr cinfo)
{
ToFunctionDestinationManager *destmgr;
destmgr = (ToFunctionDestinationManager*) cinfo->dest;
to_callback_do_write (cinfo, TO_FUNCTION_BUF_SIZE);
destmgr->pub.next_output_byte = destmgr->buffer;
destmgr->pub.free_in_buffer = TO_FUNCTION_BUF_SIZE;
return TRUE;
}
void
to_callback_terminate (j_compress_ptr cinfo)
{
ToFunctionDestinationManager *destmgr;
destmgr = (ToFunctionDestinationManager*) cinfo->dest;
to_callback_do_write (cinfo, TO_FUNCTION_BUF_SIZE - destmgr->pub.free_in_buffer);
}
static gboolean
real_save_jpeg (GdkPixbuf *pixbuf,
gchar **keys,
gchar **values,
GError **error,
gboolean to_callback,
FILE *f,
GdkPixbufSaveFunc save_func,
gpointer user_data)
{
/* FIXME error handling is broken */
struct jpeg_compress_struct cinfo;
guchar *buf = NULL;
guchar *ptr;
guchar *pixels = NULL;
JSAMPROW *jbuf;
int y = 0;
volatile int quality = 75; /* default; must be between 0 and 100 */
int i, j;
int w, h = 0;
int rowstride = 0;
int n_channels;
struct error_handler_data jerr;
ToFunctionDestinationManager to_callback_destmgr;
to_callback_destmgr.buffer = NULL;
if (keys && *keys) {
gchar **kiter = keys;
gchar **viter = values;
while (*kiter) {
if (strcmp (*kiter, "quality") == 0) {
char *endptr = NULL;
quality = strtol (*viter, &endptr, 10);
if (endptr == *viter) {
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_BAD_OPTION,
_("JPEG quality must be a value between 0 and 100; value '%s' could not be parsed."),
*viter);
return FALSE;
}
if (quality < 0 ||
quality > 100) {
/* This is a user-visible error;
* lets people skip the range-checking
* in their app.
*/
g_set_error (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_BAD_OPTION,
_("JPEG quality must be a value between 0 and 100; value '%d' is not allowed."),
quality);
return FALSE;
}
} else {
g_warning ("Unrecognized parameter (%s) passed to JPEG saver.", *kiter);
}
++kiter;
++viter;
}
}
rowstride = gdk_pixbuf_get_rowstride (pixbuf);
n_channels = gdk_pixbuf_get_n_channels (pixbuf);
w = gdk_pixbuf_get_width (pixbuf);
h = gdk_pixbuf_get_height (pixbuf);
pixels = gdk_pixbuf_get_pixels (pixbuf);
/* Allocate a small buffer to convert image data,
* and a larger buffer if doing to_callback save.
*/
buf = g_try_malloc (w * 3 * sizeof (guchar));
if (!buf) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Couldn't allocate memory for loading JPEG file"));
return FALSE;
}
if (to_callback) {
to_callback_destmgr.buffer = g_try_malloc (TO_FUNCTION_BUF_SIZE);
if (!to_callback_destmgr.buffer) {
g_set_error_literal (error,
GDK_PIXBUF_ERROR,
GDK_PIXBUF_ERROR_INSUFFICIENT_MEMORY,
_("Couldn't allocate memory for loading JPEG file"));
g_free (buf);
return FALSE;
}
}
/* set up error handling */
cinfo.err = jpeg_std_error (&(jerr.pub));
jerr.pub.error_exit = fatal_error_handler;
jerr.pub.output_message = output_message_handler;
jerr.error = error;
if (sigsetjmp (jerr.setjmp_buffer, 1)) {
jpeg_destroy_compress (&cinfo);
g_free (buf);
g_free (to_callback_destmgr.buffer);
return FALSE;
}
/* setup compress params */
jpeg_create_compress (&cinfo);
if (to_callback) {
to_callback_destmgr.pub.init_destination = to_callback_init;
to_callback_destmgr.pub.empty_output_buffer = to_callback_empty_output_buffer;
to_callback_destmgr.pub.term_destination = to_callback_terminate;
to_callback_destmgr.error = error;
to_callback_destmgr.save_func = save_func;
to_callback_destmgr.user_data = user_data;
cinfo.dest = (struct jpeg_destination_mgr*) &to_callback_destmgr;
} else {
jpeg_stdio_dest (&cinfo, f);
}
cinfo.image_width = w;
cinfo.image_height = h;
cinfo.input_components = 3;
cinfo.in_color_space = JCS_RGB;
/* set up jepg compression parameters */
jpeg_set_defaults (&cinfo);
jpeg_set_quality (&cinfo, quality, TRUE);
jpeg_start_compress (&cinfo, TRUE);
/* get the start pointer */
ptr = pixels;
/* go one scanline at a time... and save */
i = 0;
while (cinfo.next_scanline < cinfo.image_height) {
/* convert scanline from ARGB to RGB packed */
for (j = 0; j < w; j++)
memcpy (&(buf[j*3]), &(ptr[i*rowstride + j*n_channels]), 3);
/* write scanline */
jbuf = (JSAMPROW *)(&buf);
jpeg_write_scanlines (&cinfo, jbuf, 1);
i++;
y++;
}
/* finish off */
jpeg_finish_compress (&cinfo);
jpeg_destroy_compress(&cinfo);
g_free (buf);
g_free (to_callback_destmgr.buffer);
return TRUE;
}
static gboolean
gdk_pixbuf__jpeg_image_save (FILE *f,
GdkPixbuf *pixbuf,
gchar **keys,
gchar **values,
GError **error)
{
return real_save_jpeg (pixbuf, keys, values, error,
FALSE, f, NULL, NULL);
}
static gboolean
gdk_pixbuf__jpeg_image_save_to_callback (GdkPixbufSaveFunc save_func,
gpointer user_data,
GdkPixbuf *pixbuf,
gchar **keys,
gchar **values,
GError **error)
{
return real_save_jpeg (pixbuf, keys, values, error,
TRUE, NULL, save_func, user_data);
}
#ifndef INCLUDE_jpeg
#define MODULE_ENTRY(function) G_MODULE_EXPORT void function
#else
#define MODULE_ENTRY(function) void _gdk_pixbuf__jpeg_ ## function
#endif
MODULE_ENTRY (fill_vtable) (GdkPixbufModule *module)
{
module->load = gdk_pixbuf__jpeg_image_load;
module->begin_load = gdk_pixbuf__jpeg_image_begin_load;
module->stop_load = gdk_pixbuf__jpeg_image_stop_load;
module->load_increment = gdk_pixbuf__jpeg_image_load_increment;
module->save = gdk_pixbuf__jpeg_image_save;
module->save_to_callback = gdk_pixbuf__jpeg_image_save_to_callback;
}
MODULE_ENTRY (fill_info) (GdkPixbufFormat *info)
{
static GdkPixbufModulePattern signature[] = {
{ "\xff\xd8", NULL, 100 },
{ NULL, NULL, 0 }
};
static gchar * mime_types[] = {
"image/jpeg",
NULL
};
static gchar * extensions[] = {
"jpeg",
"jpe",
"jpg",
NULL
};
info->name = "jpeg";
info->signature = signature;
info->description = N_("The JPEG image format");
info->mime_types = mime_types;
info->extensions = extensions;
info->flags = GDK_PIXBUF_FORMAT_WRITABLE | GDK_PIXBUF_FORMAT_THREADSAFE;
info->license = "LGPL";
}