imagemagick/coders/hdr.c

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/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% H H DDDD RRRR %
% H H D D R R %
% HHHHH D D RRRR %
% H H D D R R %
% H H DDDD R R %
% %
% %
% Read/Write Radiance RGBE Image Format %
% %
% Software Design %
% Cristy %
% July 1992 %
% %
% %
% Copyright 1999-2021 ImageMagick Studio LLC, a non-profit organization %
% dedicated to making software imaging solutions freely available. %
% %
% You may not use this file except in compliance with the License. You may %
% obtain a copy of the License at %
% %
% https://imagemagick.org/script/license.php %
% %
% Unless required by applicable law or agreed to in writing, software %
% distributed under the License is distributed on an "AS IS" BASIS, %
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %
% See the License for the specific language governing permissions and %
% limitations under the License. %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%
*/
/*
Include declarations.
*/
#include "magick/studio.h"
#include "magick/blob.h"
#include "magick/blob-private.h"
#include "magick/cache.h"
#include "magick/colorspace.h"
#include "magick/colorspace-private.h"
#include "magick/exception.h"
#include "magick/exception-private.h"
#include "magick/image.h"
#include "magick/image-private.h"
#include "magick/list.h"
#include "magick/magick.h"
#include "magick/memory_.h"
#include "magick/monitor.h"
#include "magick/monitor-private.h"
#include "magick/pixel-accessor.h"
#include "magick/property.h"
#include "magick/quantum-private.h"
#include "magick/static.h"
#include "magick/string_.h"
#include "magick/string-private.h"
#include "magick/module.h"
/*
Forward declarations.
*/
static MagickBooleanType
WriteHDRImage(const ImageInfo *,Image *);
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% I s H D R %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% IsHDR() returns MagickTrue if the image format type, identified by the
% magick string, is Radiance RGBE image format.
%
% The format of the IsHDR method is:
%
% MagickBooleanType IsHDR(const unsigned char *magick,
% const size_t length)
%
% A description of each parameter follows:
%
% o magick: compare image format pattern against these bytes.
%
% o length: Specifies the length of the magick string.
%
*/
static MagickBooleanType IsHDR(const unsigned char *magick,
const size_t length)
{
if (length < 10)
return(MagickFalse);
if (LocaleNCompare((const char *) magick,"#?RADIANCE",10) == 0)
return(MagickTrue);
if (LocaleNCompare((const char *) magick,"#?RGBE",6) == 0)
return(MagickTrue);
return(MagickFalse);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e a d H D R I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ReadHDRImage() reads the Radiance RGBE image format and returns it. It
% allocates the memory necessary for the new Image structure and returns a
% pointer to the new image.
%
% The format of the ReadHDRImage method is:
%
% Image *ReadHDRImage(const ImageInfo *image_info,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image_info: the image info.
%
% o exception: return any errors or warnings in this structure.
%
*/
static Image *ReadHDRImage(const ImageInfo *image_info,ExceptionInfo *exception)
{
char
format[MaxTextExtent],
keyword[MaxTextExtent],
tag[MaxTextExtent],
value[MaxTextExtent];
double
gamma;
Image
*image;
int
c;
MagickBooleanType
status,
value_expected;
PixelPacket
*q;
unsigned char
*p;
ssize_t
i,
x;
ssize_t
count,
y;
unsigned char
*end,
pixel[4],
*pixels;
/*
Open image file.
*/
assert(image_info != (const ImageInfo *) NULL);
assert(image_info->signature == MagickCoreSignature);
if (image_info->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
image_info->filename);
assert(exception != (ExceptionInfo *) NULL);
assert(exception->signature == MagickCoreSignature);
image=AcquireImage(image_info);
status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
if (status == MagickFalse)
{
image=DestroyImageList(image);
return((Image *) NULL);
}
/*
Decode image header.
*/
image->columns=0;
image->rows=0;
*format='\0';
c=ReadBlobByte(image);
if (c == EOF)
{
image=DestroyImage(image);
return((Image *) NULL);
}
while (isgraph((int) ((unsigned char) c)) && (image->columns == 0) && (image->rows == 0))
{
if (c == (int) '#')
{
char
*comment;
char
*p;
size_t
length;
/*
Read comment-- any text between # and end-of-line.
*/
length=MaxTextExtent;
comment=AcquireString((char *) NULL);
for (p=comment; comment != (char *) NULL; p++)
{
c=ReadBlobByte(image);
if ((c == EOF) || (c == (int) '\n'))
break;
if ((size_t) (p-comment+1) >= length)
{
*p='\0';
length<<=1;
comment=(char *) ResizeQuantumMemory(comment,length+
MaxTextExtent,sizeof(*comment));
if (comment == (char *) NULL)
break;
p=comment+strlen(comment);
}
*p=(char) c;
}
if (comment == (char *) NULL)
ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
*p='\0';
(void) SetImageProperty(image,"comment",comment);
comment=DestroyString(comment);
c=ReadBlobByte(image);
}
else
if (isalnum((int) ((unsigned char) c)) == MagickFalse)
c=ReadBlobByte(image);
else
{
char
*p;
/*
Determine a keyword and its value.
*/
p=keyword;
do
{
if ((size_t) (p-keyword) < (MaxTextExtent-1))
*p++=c;
c=ReadBlobByte(image);
} while (isalnum((int) ((unsigned char) c)) || (c == '_'));
*p='\0';
value_expected=MagickFalse;
while ((isspace((int) ((unsigned char) c)) != 0) || (c == '='))
{
if (c == '=')
value_expected=MagickTrue;
c=ReadBlobByte(image);
}
if (LocaleCompare(keyword,"Y") == 0)
value_expected=MagickTrue;
if (value_expected == MagickFalse)
continue;
p=value;
while ((c != '\n') && (c != '\0') && (c != EOF))
{
if ((size_t) (p-value) < (MaxTextExtent-1))
*p++=c;
c=ReadBlobByte(image);
}
*p='\0';
/*
Assign a value to the specified keyword.
*/
switch (*keyword)
{
case 'F':
case 'f':
{
if (LocaleCompare(keyword,"format") == 0)
{
(void) CopyMagickString(format,value,MaxTextExtent);
break;
}
(void) FormatLocaleString(tag,MaxTextExtent,"hdr:%s",keyword);
(void) SetImageProperty(image,tag,value);
break;
}
case 'G':
case 'g':
{
if (LocaleCompare(keyword,"gamma") == 0)
{
image->gamma=StringToDouble(value,(char **) NULL);
break;
}
(void) FormatLocaleString(tag,MaxTextExtent,"hdr:%s",keyword);
(void) SetImageProperty(image,tag,value);
break;
}
case 'P':
case 'p':
{
if (LocaleCompare(keyword,"primaries") == 0)
{
float
chromaticity[6],
white_point[2];
int
count;
count=sscanf(value,"%g %g %g %g %g %g %g %g",&chromaticity[0],
&chromaticity[1],&chromaticity[2],&chromaticity[3],
&chromaticity[4],&chromaticity[5],&white_point[0],
&white_point[1]);
if (count == 8)
{
image->chromaticity.red_primary.x=chromaticity[0];
image->chromaticity.red_primary.y=chromaticity[1];
image->chromaticity.green_primary.x=chromaticity[2];
image->chromaticity.green_primary.y=chromaticity[3];
image->chromaticity.blue_primary.x=chromaticity[4];
image->chromaticity.blue_primary.y=chromaticity[5];
image->chromaticity.white_point.x=white_point[0],
image->chromaticity.white_point.y=white_point[1];
}
break;
}
(void) FormatLocaleString(tag,MaxTextExtent,"hdr:%s",keyword);
(void) SetImageProperty(image,tag,value);
break;
}
case 'Y':
case 'y':
{
char
target[] = "Y";
if (strcmp(keyword,target) == 0)
{
int
height,
width;
if (sscanf(value,"%d +X %d",&height,&width) == 2)
{
image->columns=(size_t) width;
image->rows=(size_t) height;
}
break;
}
(void) FormatLocaleString(tag,MaxTextExtent,"hdr:%s",keyword);
(void) SetImageProperty(image,tag,value);
break;
}
default:
{
(void) FormatLocaleString(tag,MaxTextExtent,"hdr:%s",keyword);
(void) SetImageProperty(image,tag,value);
break;
}
}
}
if ((image->columns == 0) && (image->rows == 0))
while (isspace((int) ((unsigned char) c)) != 0)
c=ReadBlobByte(image);
}
if ((LocaleCompare(format,"32-bit_rle_rgbe") != 0) &&
(LocaleCompare(format,"32-bit_rle_xyze") != 0))
ThrowReaderException(CorruptImageError,"ImproperImageHeader");
if ((image->columns == 0) || (image->rows == 0))
ThrowReaderException(CorruptImageError,"NegativeOrZeroImageSize");
(void) SetImageColorspace(image,RGBColorspace);
if (LocaleCompare(format,"32-bit_rle_xyze") == 0)
(void) SetImageColorspace(image,XYZColorspace);
image->compression=(image->columns < 8) || (image->columns > 0x7ffff) ?
NoCompression : RLECompression;
if (image_info->ping != MagickFalse)
{
(void) CloseBlob(image);
return(GetFirstImageInList(image));
}
status=SetImageExtent(image,image->columns,image->rows);
if (status == MagickFalse)
{
InheritException(exception,&image->exception);
return(DestroyImageList(image));
}
/*
Read RGBE (red+green+blue+exponent) pixels.
*/
pixels=(unsigned char *) AcquireQuantumMemory(image->columns,4*
sizeof(*pixels));
if (pixels == (unsigned char *) NULL)
ThrowReaderException(ResourceLimitError,"MemoryAllocationFailed");
(void) memset(pixels,0,4*image->columns*sizeof(*pixels));
for (y=0; y < (ssize_t) image->rows; y++)
{
if (image->compression != RLECompression)
{
count=ReadBlob(image,4*image->columns*sizeof(*pixels),pixels);
if (count != (ssize_t) (4*image->columns*sizeof(*pixels)))
break;
}
else
{
count=ReadBlob(image,4*sizeof(*pixel),pixel);
if (count != 4)
break;
if ((size_t) ((((size_t) pixel[2]) << 8) | pixel[3]) != image->columns)
{
(void) memcpy(pixels,pixel,4*sizeof(*pixel));
(void) ReadBlob(image,4*(image->columns-1)*sizeof(*pixels),pixels+4);
image->compression=NoCompression;
}
else
{
p=pixels;
for (i=0; i < 4; i++)
{
end=&pixels[(i+1)*image->columns];
while (p < end)
{
count=ReadBlob(image,2*sizeof(*pixel),pixel);
if (count < 1)
break;
if (pixel[0] > 128)
{
count=(ssize_t) pixel[0]-128;
if ((count == 0) || (count > (ssize_t) (end-p)))
break;
while (count-- > 0)
*p++=pixel[1];
}
else
{
count=(ssize_t) pixel[0];
if ((count == 0) || (count > (ssize_t) (end-p)))
break;
*p++=pixel[1];
if (--count > 0)
{
count=ReadBlob(image,(size_t) count*sizeof(*p),p);
if (count < 1)
break;
p+=count;
}
}
}
}
}
}
q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
if (q == (PixelPacket *) NULL)
break;
i=0;
for (x=0; x < (ssize_t) image->columns; x++)
{
if (image->compression == RLECompression)
{
pixel[0]=pixels[x];
pixel[1]=pixels[x+image->columns];
pixel[2]=pixels[x+2*image->columns];
pixel[3]=pixels[x+3*image->columns];
}
else
{
pixel[0]=pixels[i++];
pixel[1]=pixels[i++];
pixel[2]=pixels[i++];
pixel[3]=pixels[i++];
}
SetPixelRed(q,0);
SetPixelGreen(q,0);
SetPixelBlue(q,0);
if (pixel[3] != 0)
{
gamma=pow(2.0,pixel[3]-(128.0+8.0));
SetPixelRed(q,ClampToQuantum(QuantumRange*gamma*pixel[0]));
SetPixelGreen(q,ClampToQuantum(QuantumRange*gamma*pixel[1]));
SetPixelBlue(q,ClampToQuantum(QuantumRange*gamma*pixel[2]));
}
q++;
}
if (SyncAuthenticPixels(image,exception) == MagickFalse)
break;
status=SetImageProgress(image,LoadImageTag,(MagickOffsetType) y,
image->rows);
if (status == MagickFalse)
break;
}
pixels=(unsigned char *) RelinquishMagickMemory(pixels);
if (EOFBlob(image) != MagickFalse)
ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
image->filename);
(void) CloseBlob(image);
return(GetFirstImageInList(image));
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e g i s t e r H D R I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% RegisterHDRImage() adds attributes for the Radiance RGBE image format to the
% list of supported formats. The attributes include the image format tag, a
% method to read and/or write the format, whether the format supports the
% saving of more than one frame to the same file or blob, whether the format
% supports native in-memory I/O, and a brief description of the format.
%
% The format of the RegisterHDRImage method is:
%
% size_t RegisterHDRImage(void)
%
*/
ModuleExport size_t RegisterHDRImage(void)
{
MagickInfo
*entry;
entry=SetMagickInfo("HDR");
entry->decoder=(DecodeImageHandler *) ReadHDRImage;
entry->encoder=(EncodeImageHandler *) WriteHDRImage;
entry->description=ConstantString("Radiance RGBE image format");
entry->magick_module=ConstantString("HDR");
entry->magick=(IsImageFormatHandler *) IsHDR;
(void) RegisterMagickInfo(entry);
return(MagickImageCoderSignature);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% U n r e g i s t e r H D R I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% UnregisterHDRImage() removes format registrations made by the
% HDR module from the list of supported formats.
%
% The format of the UnregisterHDRImage method is:
%
% UnregisterHDRImage(void)
%
*/
ModuleExport void UnregisterHDRImage(void)
{
(void) UnregisterMagickInfo("HDR");
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% W r i t e H D R I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% WriteHDRImage() writes an image in the Radience RGBE image format.
%
% The format of the WriteHDRImage method is:
%
% MagickBooleanType WriteHDRImage(const ImageInfo *image_info,
% Image *image)
%
% A description of each parameter follows.
%
% o image_info: the image info.
%
% o image: The image.
%
*/
static size_t HDRWriteRunlengthPixels(Image *image,unsigned char *pixels)
{
#define MinimumRunlength 4
size_t
p,
q;
size_t
runlength;
ssize_t
count,
previous_count;
unsigned char
pixel[2];
for (p=0; p < image->columns; )
{
q=p;
runlength=0;
previous_count=0;
while ((runlength < MinimumRunlength) && (q < image->columns))
{
q+=runlength;
previous_count=(ssize_t) runlength;
runlength=1;
while ((pixels[q] == pixels[q+runlength]) &&
((q+runlength) < image->columns) && (runlength < 127))
runlength++;
}
if ((previous_count > 1) && (previous_count == (ssize_t) (q-p)))
{
pixel[0]=(unsigned char) (128+previous_count);
pixel[1]=pixels[p];
if (WriteBlob(image,2*sizeof(*pixel),pixel) < 1)
break;
p=q;
}
while (p < q)
{
count=(ssize_t) (q-p);
if (count > 128)
count=128;
pixel[0]=(unsigned char) count;
if (WriteBlob(image,sizeof(*pixel),pixel) < 1)
break;
if (WriteBlob(image,(size_t) count*sizeof(*pixel),&pixels[p]) < 1)
break;
p+=count;
}
if (runlength >= MinimumRunlength)
{
pixel[0]=(unsigned char) (128+runlength);
pixel[1]=pixels[q];
if (WriteBlob(image,2*sizeof(*pixel),pixel) < 1)
break;
p+=runlength;
}
}
return(p);
}
static MagickBooleanType WriteHDRImage(const ImageInfo *image_info,Image *image)
{
char
header[MaxTextExtent];
const char
*property;
MagickBooleanType
status;
const PixelPacket
*p;
ssize_t
i,
x;
size_t
length;
ssize_t
count,
y;
unsigned char
pixel[4],
*pixels;
/*
Open output image file.
*/
assert(image_info != (const ImageInfo *) NULL);
assert(image_info->signature == MagickCoreSignature);
assert(image != (Image *) NULL);
assert(image->signature == MagickCoreSignature);
if (image->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
status=OpenBlob(image_info,image,WriteBinaryBlobMode,&image->exception);
if (status == MagickFalse)
return(status);
if (IsRGBColorspace(image->colorspace) == MagickFalse)
(void) TransformImageColorspace(image,sRGBColorspace);
/*
Write header.
*/
(void) memset(header,' ',MaxTextExtent);
length=CopyMagickString(header,"#?RADIANCE\n",MaxTextExtent);
(void) WriteBlob(image,length,(unsigned char *) header);
property=GetImageProperty(image,"comment");
if ((property != (const char *) NULL) &&
(strchr(property,'\n') == (char *) NULL))
{
count=FormatLocaleString(header,MagickPathExtent,"#%.*s\n",
MagickPathExtent-3,property);
(void) WriteBlob(image,(size_t) count,(unsigned char *) header);
}
property=GetImageProperty(image,"hdr:exposure");
if (property != (const char *) NULL)
{
count=FormatLocaleString(header,MaxTextExtent,"EXPOSURE=%g\n",
strtod(property,(char **) NULL));
(void) WriteBlob(image,(size_t) count,(unsigned char *) header);
}
if (image->gamma != 0.0)
{
count=FormatLocaleString(header,MaxTextExtent,"GAMMA=%g\n",image->gamma);
(void) WriteBlob(image,(size_t) count,(unsigned char *) header);
}
count=FormatLocaleString(header,MaxTextExtent,
"PRIMARIES=%g %g %g %g %g %g %g %g\n",
image->chromaticity.red_primary.x,image->chromaticity.red_primary.y,
image->chromaticity.green_primary.x,image->chromaticity.green_primary.y,
image->chromaticity.blue_primary.x,image->chromaticity.blue_primary.y,
image->chromaticity.white_point.x,image->chromaticity.white_point.y);
(void) WriteBlob(image,(size_t) count,(unsigned char *) header);
length=CopyMagickString(header,"FORMAT=32-bit_rle_rgbe\n\n",MaxTextExtent);
(void) WriteBlob(image,length,(unsigned char *) header);
count=FormatLocaleString(header,MaxTextExtent,"-Y %.20g +X %.20g\n",
(double) image->rows,(double) image->columns);
(void) WriteBlob(image,(size_t) count,(unsigned char *) header);
/*
Write HDR pixels.
*/
pixels=(unsigned char *) AcquireQuantumMemory(image->columns+128,4*
sizeof(*pixels));
if (pixels == (unsigned char *) NULL)
ThrowWriterException(ResourceLimitError,"MemoryAllocationFailed");
(void) memset(pixels,0,4*(image->columns+128)*sizeof(*pixels));
for (y=0; y < (ssize_t) image->rows; y++)
{
p=GetVirtualPixels(image,0,y,image->columns,1,&image->exception);
if (p == (const PixelPacket *) NULL)
break;
if ((image->columns >= 8) && (image->columns <= 0x7ffff))
{
pixel[0]=2;
pixel[1]=2;
pixel[2]=(unsigned char) (image->columns >> 8);
pixel[3]=(unsigned char) (image->columns & 0xff);
count=WriteBlob(image,4*sizeof(*pixel),pixel);
if (count != (ssize_t) (4*sizeof(*pixel)))
break;
}
i=0;
for (x=0; x < (ssize_t) image->columns; x++)
{
double
gamma;
pixel[0]=0;
pixel[1]=0;
pixel[2]=0;
pixel[3]=0;
gamma=QuantumScale*GetPixelRed(p);
if ((QuantumScale*GetPixelGreen(p)) > gamma)
gamma=QuantumScale*GetPixelGreen(p);
if ((QuantumScale*GetPixelBlue(p)) > gamma)
gamma=QuantumScale*GetPixelBlue(p);
if (gamma > MagickEpsilon)
{
int
exponent;
gamma=frexp(gamma,&exponent)*256.0/gamma;
if (GetPixelRed(p) > 0)
pixel[0]=(unsigned char) (gamma*QuantumScale*GetPixelRed(p));
if (GetPixelGreen(p) > 0)
pixel[1]=(unsigned char) (gamma*QuantumScale*GetPixelGreen(p));
if (GetPixelBlue(p) > 0)
pixel[2]=(unsigned char) (gamma*QuantumScale*GetPixelBlue(p));
pixel[3]=(unsigned char) (exponent+128);
}
if ((image->columns >= 8) && (image->columns <= 0x7ffff))
{
pixels[x]=pixel[0];
pixels[x+image->columns]=pixel[1];
pixels[x+2*image->columns]=pixel[2];
pixels[x+3*image->columns]=pixel[3];
}
else
{
pixels[i++]=pixel[0];
pixels[i++]=pixel[1];
pixels[i++]=pixel[2];
pixels[i++]=pixel[3];
}
p++;
}
if ((image->columns >= 8) && (image->columns <= 0x7ffff))
{
for (i=0; i < 4; i++)
length=HDRWriteRunlengthPixels(image,&pixels[i*image->columns]);
}
else
{
count=WriteBlob(image,4*image->columns*sizeof(*pixels),pixels);
if (count != (ssize_t) (4*image->columns*sizeof(*pixels)))
break;
}
status=SetImageProgress(image,SaveImageTag,(MagickOffsetType) y,
image->rows);
if (status == MagickFalse)
break;
}
pixels=(unsigned char *) RelinquishMagickMemory(pixels);
(void) CloseBlob(image);
return(MagickTrue);
}