Bug 144454 - Loading and storing DICOM again looses important information

Retain dicom tags using parasites. Patch by Paul Epperson.
This commit is contained in:
Sven Neumann
2010-05-10 20:43:12 +02:00
parent 67ba62154e
commit 55bc1fa84f
2 changed files with 616 additions and 111 deletions

View File

@ -28,6 +28,7 @@ Global data follows no strict rules.
"tiff" : The standard GIMP TIFF plugin
"jpeg" : The standard GIMP JPEG plugin
"png" : The standard GIMP PNG plugin
"dcm" : The standard GIMP DICOM plugin
"gimp" : For common and standard parasites
------------------------------------------------------------------
@ -215,6 +216,13 @@ Global data follows no strict rules.
from GtkPageSetup. The content is identical to what is stored in
~/.gimp-2.x/print-page-setup.
"dcm/XXXX-XXXX-AA" (IMAGE, PERSISTANT)
These parasites are stored by the Dicom plug-in and hold the DICOM
element information for that image. The format is raw binary data
as read from the original image.
where: XXXX is a 4-digit ascii encoded hexadecimal number
AA is a two character ascii value representing the Dicom
element's Value Represenation (VR)
------------------------------------------------------------------
*** KNOWN LAYER/DRAWABLE PARASITES:

View File

@ -84,16 +84,9 @@ static void add_tag_pointer (GByteArray *group_stream,
const gchar *value_rep,
const guint8 *data,
gint length);
static void add_tag_string (GByteArray *group_stream,
gint group,
gint element,
const gchar *value_rep,
const gchar *s);
static void add_tag_int (GByteArray *group_stream,
gint group,
gint element,
const gchar *value_rep,
gint value);
static GSList * dicom_add_tags (FILE *DICOM,
GByteArray *group_stream,
GSList *elements);
static gboolean write_group_to_file (FILE *DICOM,
gint group,
GByteArray *group_stream);
@ -295,6 +288,23 @@ run (const gchar *name,
values[0].data.d_status = status;
}
/**
* add_parasites_to_image:
* @data: pointer to a GimpParasite to be attached to the image specified by @user_data.
* @user_data: pointer to the image_ID to which parasite @data should be added.
*
* Attaches parasite to image and also frees that parasite
**/
static void
add_parasites_to_image (gpointer data,
gpointer user_data)
{
GimpParasite *parasite = (GimpParasite *)data;
gint32 *image_ID = (gint32 *)user_data;
gimp_image_parasite_attach (*image_ID, parasite);
gimp_parasite_free (parasite);
}
static gint32
load_image (const gchar *filename,
GError **error)
@ -303,6 +313,7 @@ load_image (const gchar *filename,
gint32 volatile image_ID = -1;
gint32 layer_ID;
GimpDrawable *drawable;
GSList *elements = NULL;
FILE *DICOM;
gchar buf[500]; /* buffer for random things like scanning */
DicomInfo *dicominfo;
@ -314,6 +325,7 @@ load_image (const gchar *filename,
gint high_bit = 0;
guint8 *pix_buf = NULL;
gboolean is_signed = FALSE;
guint8 in_sequence = 0;
/* open the file */
DICOM = g_fopen (filename, "rb");
@ -433,7 +445,16 @@ load_image (const gchar *filename,
/* Sequence of items - just ignore the delimiters... */
if (element_length == 0xffffffff)
{
in_sequence = 1;
continue;
}
/* End of Sequence tag */
if (tag == 0xFFFEE0DD)
{
in_sequence = 0;
continue;
}
/* Sequence of items item tag... Ignore as well */
if (tag == 0xFFFEE000)
@ -454,6 +475,12 @@ load_image (const gchar *filename,
value = g_new0 (guint8, element_length + 4);
fread (value, 1, element_length, DICOM);
/* ignore everything inside of a sequence */
if (in_sequence)
{
g_free (value);
continue;
}
/* Some special casts that are used below */
ctx_ul = *(guint32 *) value;
ctx_us = *(guint16 *) value;
@ -511,6 +538,25 @@ load_image (const gchar *filename,
}
else
{
/* save this element to a parasite for later writing */
GimpParasite *parasite;
gchar pname[255];
/* all elements are retrievable using gimp_parasite_list() */
g_snprintf(pname,sizeof(pname),"dcm/%04x-%04x-%s",group_word,element_word,value_rep);
if ((parasite = gimp_parasite_new (pname,
GIMP_PARASITE_PERSISTENT,
element_length, value)))
{
/*
* at this point, the image has not yet been created, so image_ID is not valid.
* keep the parasite around until we're able to attach it.
*/
/* gimp_image_parasite_attach (image_ID, parasite);*/
/* gimp_parasite_free (parasite); */
/* add to our list of parasites to be added (prepending for speed. we'll reverse it later) */
elements = g_slist_prepend (elements,parasite);
}
g_free (value);
}
}
@ -571,6 +617,14 @@ load_image (const gchar *filename,
dicom_loader (pix_buf, dicominfo, &pixel_rgn);
if (elements)
{
/* flip the parasites back around into the order they were created (read from the file) */
elements = g_slist_reverse (elements);
/* and add each one to the image */
g_slist_foreach (elements,add_parasites_to_image,(gpointer)&image_ID);
g_slist_free (elements);
}
/* free the structures */
g_free (pix_buf);
g_free (dicominfo);
@ -578,8 +632,9 @@ load_image (const gchar *filename,
/* close the file */
fclose (DICOM);
/* Tell GIMP to display the image. */
gimp_drawable_flush (drawable);
/* Tell GIMP to display the image and detach. */
/* gimp_drawable_flush (drawable); -- implicitely done via gimp_drawable_detach() */
gimp_drawable_detach (drawable);
return image_ID;
}
@ -737,6 +792,446 @@ toggle_endian2 (guint16 *buf16,
}
}
typedef struct _DicomElement {
guint16 group_word;
guint16 element_word;
gchar value_rep[3];
guint32 element_length;
guint8 *value;
gint free;
} DICOMELEMENT;
/**
* dicom_add_element:
* @elements: head of a GSList containing DICOMELEMENT structures.
* @group_word: Dicom Element group number for the tag to be added to @elements.
* @element_word: Dicom Element element number for the tag to be added to @elements.
* @value_rep: a string representing the Dicom VR for the new element.
* @value: a pointer to an integer containing the value for the element to be created.
*
* Creates a DICOMELEMENT object and inserts it into @elements.
*
* Return value: the new head of @elements
**/
static GSList *
dicom_add_element (GSList *elements,
guint16 group_word,
guint16 element_word,
gchar *value_rep,
guint32 element_length,
guint8 *value,
gint copy)
{
DICOMELEMENT *element = g_new0 (DICOMELEMENT, 1);
if (element)
{
element->free = 0;
if (copy)
{
guint8 *v = g_new (guint8,element_length);
if (v)
{
memcpy (v,value,element_length);
value = v;
element->free = 1;
}
}
element->group_word = group_word;
element->element_word = element_word;
strncpy (element->value_rep,value_rep,sizeof (element->value_rep));
element->element_length = element_length;
element->value = value;
elements = g_slist_prepend (elements,element);
}
return elements;
}
/**
* dicom_add_element_int:
* @elements: head of a GSList containing DICOMELEMENT structures.
* @group_word: Dicom Element group number for the tag to be added to @elements.
* @element_word: Dicom Element element number for the tag to be added to @elements.
* @value_rep: a string representing the Dicom VR for the new element.
* @value: a pointer to an integer containing the value for the element to be created.
*
* Creates a DICOMELEMENT object from the passed integer pointer and adds it to @elements.
* Note: value should be the address of a guint16 for @value_rep==%US or guint32 for other values of @value_rep
*
* Return value: the new head of @elements
*/
static GSList *
dicom_add_element_int (GSList *elements,
guint16 group_word,
guint16 element_word,
gchar *value_rep,
guint8 *value)
{
guint32 len;
if (strcmp (value_rep, "US") == 0)
len = 2;
else
len = 4;
return dicom_add_element (elements,group_word,element_word,value_rep,len,value,0);
}
/**
* dicom_element_done:
* @data: pointer to a DICOMELEMENT structure which is to be destroyed.
* @user_data: unused.
*
* Destroys the DICOMELEMENT passed as @data
**/
static void
dicom_element_done (gpointer data,
gpointer user_data)
{
if (data)
{
DICOMELEMENT *e = (DICOMELEMENT *)data;
if (e->free)
{
g_free (e->value);
}
g_free (data);
}
}
/**
* dicom_elements_destroy:
* @elements: head of a GSList containing DICOMELEMENT structures.
*
* Destroys the list of DICOMELEMENTs
**/
static void
dicom_elements_destroy (GSList *elements)
{
if (elements)
{
g_slist_foreach (elements,dicom_element_done,NULL);
g_slist_free (elements);
}
}
/**
* dicom_destroy_element:
* @elements: head of a GSList containing DICOMELEMENT structures.
* @ele: a DICOMELEMENT structure to be removed from @elements
*
* Removes the specified DICOMELEMENT from @elements and Destroys it
*
* Return value: the new head of @elements
**/
static GSList *
dicom_destroy_element (GSList *elements,
DICOMELEMENT *ele)
{
if (ele)
{
elements = g_slist_remove_all (elements,ele);
if (ele->free)
{
g_free (ele->value);
}
g_free (ele);
}
return elements;
}
/**
* dicom_elements_compare:
* @a: pointer to a DICOMELEMENT structure.
* @b: pointer to a DICOMELEMENT structure.
*
* Determines the equality of @a and @b as strcmp
*
* Return value: an integer indicating the equality of @a and @b.
**/
static gint
dicom_elements_compare (gconstpointer a,
gconstpointer b)
{
DICOMELEMENT *e1 = (DICOMELEMENT *)a;
DICOMELEMENT *e2 = (DICOMELEMENT *)b;
if (e1->group_word == e2->group_word)
{
if (e1->element_word == e2->element_word)
{
return 0;
}
else if (e1->element_word > e2->element_word)
{
return 1;
}
else
{
return -1;
}
}
else if (e1->group_word < e2->group_word)
{
return -1;
}
return 1;
}
/**
* dicom_element_find_by_num:
* @head: head of a GSList containing DICOMELEMENT structures.
* @group_word: Dicom Element group number for the tag to be found.
* @element_word: Dicom Element element number for the tag to be found.
*
* Retrieves the specified DICOMELEMENT from @head, if available.
*
* Return value: a DICOMELEMENT matching the specified group,element, or NULL if the specified element was not found.
**/
static DICOMELEMENT *
dicom_element_find_by_num (GSList *head,
guint16 group_word,
guint16 element_word)
{
DICOMELEMENT data = {group_word,element_word,"",0,NULL};
GSList *ele = g_slist_find_custom (head,&data,dicom_elements_compare);
return ele?ele->data:NULL;
}
/**
* dicom_get_elements_list:
* @image_ID: the image_ID from which to read parasites in order to retrieve the dicom elements
*
* Reads all DICOMELEMENTs from the specified image's parasites.
*
* Return value: a GSList of all known dicom elements
**/
static GSList *
dicom_get_elements_list (gint32 image_ID)
{
GSList *elements = NULL;
GimpParasite *parasite;
gchar **parasites = NULL;
gint count = 0;
gimp_image_parasite_list (image_ID,&count,&parasites);
if (parasites && count > 0)
{
gint i;
for (i = 0; i < count; i++)
{
if (strncmp (parasites[i],"dcm",3) == 0)
{
parasite = gimp_image_parasite_find (image_ID,parasites[i]);
if (parasite)
{
gchar buf[1024];
gchar *ptr1;
gchar *ptr2;
gchar value_rep[3]="";
guint16 group_word=0;
guint16 element_word=0;
/* sacrificial buffer */
strncpy (buf,parasites[i],sizeof (buf));
/* buf should now hold a string of the form dcm/XXXX-XXXX-AA
* where XXXX are Hex values for group and element respectively
* AA is the Value Representation of the element
*
* start off by jumping over the dcm/ to the first Hex blob
*/
ptr1 = strchr (buf,'/');
if (ptr1)
{
gchar t[15];
ptr1++;
ptr2 = strchr (ptr1,'-');
if (ptr2)
{
*ptr2 = '\0';
}
g_snprintf (t,sizeof (t),"0x%s",ptr1);
group_word = (guint16)g_ascii_strtoull (t,NULL,16);
ptr1 = ptr2+1;
}
/* now get the second Hex blob */
if (ptr1)
{
gchar t[15];
ptr2 = strchr (ptr1,'-');
if (ptr2)
{
*ptr2 = '\0';
}
g_snprintf (t,sizeof (t),"0x%s",ptr1);
element_word = (guint16)g_ascii_strtoull (t,NULL,16);
ptr1 = ptr2+1;
}
/* and lastly, the VR */
if (ptr1)
{
strncpy (value_rep,ptr1,sizeof (value_rep));
}
/*
* If all went according to plan, we should be able to add this element
*/
if (group_word > 0 && element_word > 0)
{
/* create a copy of the parasite's data so we can drop the const qualifier */
guint32 len = gimp_parasite_data_size (parasite);
if (len > 0)
{
guint8 *val = g_new0 (guint8,len);
if (val)
{
memcpy (val,gimp_parasite_data (parasite),len);
/* and add the dicom element, asking to have it's value copied for later garbage collection */
elements = dicom_add_element (elements,group_word,element_word,value_rep,len,val,1);
g_free (val);
}
}
}
gimp_parasite_free (parasite);
}
}
/* make sure we free each individual parasite name, in addition to the array of names */
g_free (parasites[i]);
}
}
/* cleanup the array of names */
if (parasites)
{
g_free (parasites);
}
return elements;
}
/**
* dicom_remove_gimp_specified_elements:
* @elements: GSList to remove elements from
* @samples_per_pixel: samples per pixel of the image to be written.
* if set to %3 the planar configuration for color images
* will also be removed from @elements
*
* Removes certain DICOMELEMENTs from the elements list which are specific to the output of this plugin.
*
* Return value: the new head of @elements
**/
static GSList *
dicom_remove_gimp_specified_elements (GSList *elements,
gint samples_per_pixel)
{
DICOMELEMENT remove[] = {
/* Image presentation group */
/* Samples per pixel */
{0x0028, 0x0002, "", 0, NULL},
/* Photometric interpretation */
{0x0028, 0x0004, "", 0, NULL},
/* rows */
{0x0028, 0x0010, "", 0, NULL},
/* columns */
{0x0028, 0x0011, "", 0, NULL},
/* Bits allocated */
{0x0028, 0x0100, "", 0, NULL},
/* Bits Stored */
{0x0028, 0x0101, "", 0, NULL},
/* High bit */
{0x0028, 0x0102, "", 0, NULL},
/* Pixel representation */
{0x0028, 0x0103, "", 0, NULL},
{0,0,"",0,NULL}
};
DICOMELEMENT *ele;
gint i;
/*
* Remove all Dicom elements which will be set as part of the writing of the new file
*/
for (i=0; remove[i].group_word > 0;i++)
{
if ((ele = dicom_element_find_by_num (elements,remove[i].group_word,remove[i].element_word)))
{
elements = dicom_destroy_element (elements,ele);
}
}
/* special case - allow this to be overwritten if necessary */
if (samples_per_pixel == 3)
{
/* Planar configuration for color images */
if ((ele = dicom_element_find_by_num (elements,0x0028,0x0006)))
{
elements = dicom_destroy_element (elements,ele);
}
}
return elements;
}
/**
* dicom_ensure_required_elements_present:
* @elements: GSList to remove elements from
* @today_string: string containing today's date in DICOM format. This is used to default any required Dicom elements of date type to today's date.
*
* Defaults DICOMELEMENTs to the values set by previous version of this plugin, but only if they do not already exist.
*
* Return value: the new head of @elements
**/
static GSList *
dicom_ensure_required_elements_present (GSList *elements,
gchar *today_string)
{
DICOMELEMENT defaults[] = {
/* Meta element group */
/* 0002,0001 - File Meta Information Version */
{0x0002,0x0001,"OB",2,(guint8 *)"\0\1"},
/* 0002,0010 - Transfer syntax uid */
{0x0002,0x0001,"UI",strlen ("1.2.840.10008.1.2.1"),(guint8 *)"1.2.840.10008.1.2.1"},
/* 0002,0013 - Implementation version name */
{0x0002,0x0013,"SH",strlen ("Gimp Dicom Plugin 1.0"),(guint8 *)"Gimp Dicom Plugin 1.0"},
/* Identifying group */
/* Study date */
{0x0008,0x0020,"DA",strlen (today_string),(guint8 *)today_string},
/* Series date */
{0x0008,0x0021,"DA",strlen (today_string),(guint8 *)today_string},
/* Acquisition date */
{0x0008,0x0022,"DA",strlen (today_string),(guint8 *)today_string},
/* Content Date */
{0x0008,0x0023,"DA",strlen (today_string),(guint8 *)today_string},
/* Modality - I have to add something.. */
{0x0008,0x0060,"CS",strlen ("MR"),(guint8 *)"MR"},
/* Patient group */
/* Patient name */
{0x0010, 0x0010, "PN", strlen ("DOE^WILBER"), (guint8 *)"DOE^WILBER"},
/* Patient ID */
{0x0010, 0x0020, "CS", strlen ("314159265"), (guint8 *)"314159265"},
/* Patient Birth date */
{0x0010, 0x0030, "DA", strlen (today_string), (guint8 *)today_string},
/* Patient sex */
{0x0010, 0x0040, "CS", strlen (""), (guint8 *)"" /* unknown */},
/* Relationship group */
/* Instance number */
{0x0020, 0x0013, "IS", strlen ("1"), (guint8 *)"1"},
{0,0,"",0,NULL}
};
gint i;
/*
* Make sure that all of the default elements have a value
*/
for (i=0; defaults[i].group_word > 0;i++)
{
if (dicom_element_find_by_num (elements,defaults[i].group_word,defaults[i].element_word) == NULL)
{
elements = dicom_add_element (elements,defaults[i].group_word,defaults[i].element_word,
defaults[i].value_rep,defaults[i].element_length,defaults[i].value,0);
}
}
return elements;
}
/* save_image() saves an image in the dicom format. The DICOM format
* requires a lot of tags to be set. Some of them have real uses, others
* must just be filled with dummy values.
@ -752,12 +1247,17 @@ save_image (const gchar *filename,
GimpDrawable *drawable;
GimpPixelRgn pixel_rgn;
GByteArray *group_stream;
GSList *elements = NULL;
gint group;
GDate *date;
gchar today_string[16];
gchar *photometric_interp;
gint samples_per_pixel;
gboolean retval = TRUE;
guint16 zero = 0;
guint16 seven = 7;
guint16 eight = 8;
guchar *src = NULL;
drawable_type = gimp_drawable_type (drawable_ID);
drawable = gimp_drawable_get (drawable_ID);
@ -814,101 +1314,129 @@ save_image (const gchar *filename,
group_stream = g_byte_array_new ();
/* Meta element group */
group = 0x0002;
/* 0002,0001 - File Meta Information Version */
add_tag_pointer (group_stream, group, 0x0001, "OB",
(const guint8 *) "\0\1", 2);
/* 0002,0010 - Transfer syntax uid */
add_tag_string (group_stream, group, 0x0010, "UI", "1.2.840.10008.1.2.1");
/* 0002,0013 - Implementation version name */
add_tag_string (group_stream, group, 0x0013, "SH", "Gimp Dicom Plugin 1.0");
write_group_to_file (DICOM, group, group_stream);
elements = dicom_get_elements_list (image_ID);
if (0/*replaceElementsList*/)
{
/* to do */
}
else if (1/*insist_on_basic_elements*/)
{
elements = dicom_ensure_required_elements_present (elements,today_string);
}
/* Identifying group */
group = 0x0008;
/* Study date */
add_tag_string (group_stream, group, 0x0020, "DA", today_string);
/* Series date */
add_tag_string (group_stream, group, 0x0021, "DA", today_string);
/* Acquisition date */
add_tag_string (group_stream, group, 0x0022, "DA", today_string);
/* Content Date */
add_tag_string (group_stream, group, 0x0023, "DA", today_string);
/* Modality - I have to add something.. */
add_tag_string (group_stream, group, 0x0060, "CS", "MR");
write_group_to_file (DICOM, group, group_stream);
/* Patient group */
group = 0x0010;
/* Patient name */
add_tag_string (group_stream, group, 0x0010, "PN", "Wilber Doe");
/* Patient ID */
add_tag_string (group_stream, group, 0x0020, "CS", "314159265");
/* Patient Birth date */
add_tag_string (group_stream, group, 0x0030, "DA", today_string);
/* Patient sex */
add_tag_string (group_stream, group, 0x0040, "CS", "" /* unknown */);
write_group_to_file (DICOM, group, group_stream);
/* Relationship group */
group = 0x0020;
/* Instance number */
add_tag_string (group_stream, group, 0x0013, "IS", "1");
write_group_to_file (DICOM, group, group_stream);
/*
* Set value of custom elements
*/
elements = dicom_remove_gimp_specified_elements (elements,samples_per_pixel);
/* Image presentation group */
group = 0x0028;
/* Samples per pixel */
add_tag_int (group_stream, group, 0x0002, "US", samples_per_pixel);
elements = dicom_add_element_int (elements,group,0x0002,"US",(guint8 *)&samples_per_pixel);
/* Photometric interpretation */
add_tag_string (group_stream, group, 0x0004, "CS", photometric_interp);
elements = dicom_add_element (elements,group,0x0004,"CS",strlen (photometric_interp),(guint8 *)photometric_interp,0);
/* Planar configuration for color images */
if (samples_per_pixel == 3)
add_tag_int (group_stream, group, 0x0006, "US", 0);
elements = dicom_add_element_int (elements,group,0x0006,"US",(guint8 *)&zero);
/* rows */
add_tag_int (group_stream, group, 0x0010, "US", drawable->height);
elements = dicom_add_element_int (elements, group, 0x0010, "US", (guint8 *)&(drawable->height));
/* columns */
add_tag_int (group_stream, group, 0x0011, "US", drawable->width);
elements = dicom_add_element_int (elements, group, 0x0011, "US", (guint8 *)&(drawable->width));
/* Bits allocated */
add_tag_int (group_stream, group, 0x0100, "US", 8);
elements = dicom_add_element_int (elements, group, 0x0100, "US", (guint8 *)&eight);
/* Bits Stored */
add_tag_int (group_stream, group, 0x0101, "US", 8);
elements = dicom_add_element_int (elements, group, 0x0101, "US", (guint8 *)&eight);
/* High bit */
add_tag_int (group_stream, group, 0x0102, "US", 7);
elements = dicom_add_element_int (elements, group, 0x0102, "US", (guint8 *)&seven);
/* Pixel representation */
add_tag_int (group_stream, group, 0x0103, "US", 0);
write_group_to_file (DICOM, group, group_stream);
elements = dicom_add_element_int (elements, group, 0x0103, "US", (guint8 *)&zero);
/* Pixel data */
group = 0x7fe0;
{
guchar *src;
src = g_new (guchar,
drawable->height * drawable->width * samples_per_pixel);
if (src)
{
gimp_pixel_rgn_init (&pixel_rgn, drawable,
0, 0, drawable->width, drawable->height,
FALSE, FALSE);
gimp_pixel_rgn_get_rect (&pixel_rgn,
src, 0, 0, drawable->width, drawable->height);
add_tag_pointer (group_stream, group, 0x0010, "OW", (guint8 *) src,
drawable->width * drawable->height * samples_per_pixel);
elements = dicom_add_element (elements,group,0x0010,"OW",
drawable->width * drawable->height * samples_per_pixel,
(guint8 *)src,0);
elements = dicom_add_tags (DICOM,group_stream,elements);
g_free (src);
}
retval = write_group_to_file (DICOM, group, group_stream);
else
{
retval = FALSE;
}
fclose (DICOM);
dicom_elements_destroy (elements);
g_byte_array_free (group_stream, TRUE);
gimp_drawable_detach (drawable);
return retval;
}
/**
* dicom_print_tags:
* @data: pointer to a DICOMELEMENT structure which is to be written to file
* @user_data: structure containing state information and output parameters
*
* Writes the specified DICOMELEMENT to @user_data's group_stream member.
* Between groups, flushes the group_stream to @user_data's DICOM member.
*/
static void
dicom_print_tags(gpointer data,
gpointer user_data)
{
struct {
FILE *DICOM;
GByteArray *group_stream;
gint last_group;
} *d = user_data;
DICOMELEMENT *e = (DICOMELEMENT *)data;
if (d->last_group >= 0 && e->group_word != d->last_group)
{
write_group_to_file (d->DICOM, d->last_group, d->group_stream);
}
add_tag_pointer (d->group_stream,e->group_word,e->element_word,e->value_rep,e->value,e->element_length);
d->last_group = e->group_word;
}
/**
* dicom_add_tags:
* @DICOM: File pointer to which @elements should be written.
* @group_stream: byte array used for staging Dicom Element groups before flushing them to disk.
* @elements: GSList container the Dicom Element elements from
*
* Writes all Dicom tags in @elements to the file @DICOM
*
* Return value: the new head of @elements
**/
static GSList *
dicom_add_tags(FILE *DICOM,
GByteArray *group_stream,
GSList *elements)
{
struct {
FILE *DICOM;
GByteArray *group_stream;
gint last_group;
} data = {DICOM,group_stream,-1};
elements = g_slist_sort (elements,dicom_elements_compare);
g_slist_foreach (elements,dicom_print_tags,&data);
/* make sure that the final group is written to the file */
write_group_to_file (data.DICOM, data.last_group, data.group_stream);
return elements;
}
/* add_tag_pointer () adds to the group_stream one single value with its
* corresponding value_rep. Note that we use "explicit VR".
*/
@ -986,37 +1514,6 @@ add_tag_pointer (GByteArray *group_stream,
}
}
/* Convenience function for adding a string to the dicom stream */
static void
add_tag_string (GByteArray *group_stream,
gint group,
gint element,
const gchar *value_rep,
const gchar *s)
{
add_tag_pointer (group_stream,
group, element, value_rep, (const guint8 *) s, strlen (s));
}
/* Convenience function for adding an integer to the dicom stream */
static void
add_tag_int (GByteArray *group_stream,
gint group,
gint element,
const gchar *value_rep,
gint value)
{
gint len;
if (strcmp (value_rep, "US") == 0)
len = 2;
else
len = 4;
add_tag_pointer (group_stream,
group, element, value_rep, (const guint8 *) &value, len);
}
/* Once a group has been built it has to be wrapped with a meta-group
* tag before it is written to the DICOM file. This is done by
* write_group_to_file.