Add GIF loader.

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/gui/trunk@18339 72102866-910b-0410-8b05-ffd578937521

ChangeLog

@@ -1,3 +1,19 @@
+2004-01-08 19:41  Alexander Malmberg <alexander@malmberg.org>
+
+	* configure.ac: Add a check for libungif.
+	* configure, Headers/Additions/GNUstepGUI/config.h.in: Regenerate.
+
+	* Source/GNUmakefile: Add NSBitmapImageRep+GIF.m.
+
+	* Source/NSBitmapImageRep+GIF.m, Source/NSBitmapImageRep+GIF.h:
+	New files with the GIF image loader.
+
+	* Source/NSBitmapImageRep.m (+canInitWithData:)	Check if the GIF
+	loader can handle the data.
+	(+imageUnfilteredFileTypes): Add ".gif".
+	(+imageRepsWithData:, -initWithData:): Use the GIF loader to load
+	GIF images.
+
 2004-01-08  Fred Kiefer <FredKiefer@gmx.de>
 
 	* Source/NSActionCell.m (-initWithCoder:) Don't decode the control

Headers/Additions/GNUstepGUI/config.h.in

@@ -24,6 +24,9 @@
 /* Define to 1 if you have the `tiff' library (-ltiff). */
 #undef HAVE_LIBTIFF
 
+/* Define to 1 if you have the `ungif' library (-lungif). */
+#undef HAVE_LIBUNGIF
+
 /* Define to 1 if you have the `z' library (-lz). */
 #undef HAVE_LIBZ
 

Source/NSBitmapImageRep+GIF.h

@@ -0,0 +1,42 @@
+/* NSBitmapImageRep+GIF.h
+
+   Functionality for reading GIF images
+
+   Copyright (C) 2003 Free Software Foundation, Inc.
+   
+   Written by:  Stefan Kleine Stegemann <stefan@wms-network.de>
+   Date: Nov 2003
+   
+   This file is part of the GNUstep GUI Library.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library 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
+   Library General Public License for more details.
+   
+   You should have received a copy of the GNU Library General Public
+   License along with this library; see the file COPYING.LIB.
+   If not, write to the Free Software Foundation,
+   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+   */ 
+
+#ifndef _NSBitmapImageRep_GIF_H_include
+#define _NSBitmapImageRep_GIF_H_include
+
+#include "AppKit/NSBitmapImageRep.h"
+
+@interface NSBitmapImageRep (GIFReading)
+
++ (BOOL) _bitmapIsGIF: (NSData *)imageData;
+- (id) _initBitmapFromGIF: (NSData *)imageData
+             errorMessage: (NSString **)errorMsg;
+
+@end
+
+#endif // _NSBitmapImageRep_GIF_H_include
+

Source/NSBitmapImageRep+GIF.m

@@ -0,0 +1,348 @@
+/* NSBitmapImageRep+GIF.m
+
+   Methods for reading GIF images
+
+   Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+   
+   Written by:  Stefan Kleine Stegemann <stefan@wms-network.de>
+   Date: Nov 2003
+
+   This file is part of the GNUstep GUI Library.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library 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
+   Library General Public License for more details.
+   
+   You should have received a copy of the GNU Library General Public
+   License along with this library; see the file COPYING.LIB.
+   If not, write to the Free Software Foundation,
+   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+   */ 
+
+#include "config.h"
+#include "NSBitmapImageRep+GIF.h"
+
+#if HAVE_LIBUNGIF
+
+#include <gif_lib.h>
+
+#include <Foundation/NSString.h>
+#include <Foundation/NSData.h>
+#include <Foundation/NSException.h>
+#include "AppKit/NSGraphics.h"
+
+
+/* -----------------------------------------------------------
+   The following types and functions are for interacting with
+   the gif library.
+   ----------------------------------------------------------- */
+
+/* settings for reading interlaced images */
+static int InterlaceOffset[] = { 0, 4, 2, 1 };
+static int InterlaceJumps[]  = { 8, 8, 4, 2 };
+
+/* Holds the information for the input function.  */
+typedef struct gs_gif_input_src
+{
+  const void *data;
+  unsigned    length;
+  unsigned    pos;
+} gs_gif_input_src;
+
+/* Provides data for the gif library.  */
+static int gs_gif_input(GifFileType *file, GifByteType *buffer, int len)
+{
+  /* according the the libungif sources, this functions has
+     to act like fread. */
+  int bytesRead;
+  gs_gif_input_src *src = (gs_gif_input_src *)file->UserData;
+
+  if (src->pos < src->length)
+    {
+      if ((src->pos + len) > src->length)
+	{
+	  bytesRead = (src->length - src->pos);
+	}
+      else
+	{
+	  bytesRead = len;
+	}
+
+      /* We have to copy the data here, looking at
+         the libungif source makes this clear.  */
+      memcpy(buffer, src->data + src->pos, bytesRead);
+      src->pos = src->pos + bytesRead;
+    }
+  else
+    {
+      bytesRead = 0;
+    }
+
+  return bytesRead;
+}
+
+
+/* Initialze a new input source to be used with
+   gs_gif_input. The passed structure has to be
+   allocated outside this function. */
+static void gs_gif_init_input_source(gs_gif_input_src *src, NSData *data)
+{
+  src->data   = [data bytes];
+  src->length = [data length];
+  src->pos    = 0;
+}
+
+
+/* -----------------------------------------------------------
+   The gif loading part of NSBitmapImageRep
+   ----------------------------------------------------------- */
+
+@implementation NSBitmapImageRep (GIFReading)
+
+/* Return YES if this looks like a GIF. */
++ (BOOL) _bitmapIsGIF: (NSData *)imageData
+{
+  struct gs_gif_input_src src;
+  GifFileType*            file;
+
+  if (!imageData || ![imageData length])
+    {
+      return NO;
+    }
+
+  gs_gif_init_input_source(&src, imageData);
+  file = DGifOpen(&src, gs_gif_input);
+  if (file == NULL)
+    {
+      /* we do not use giferror here because it doesn't
+         seem to be thread-safe (the error code is a global
+         variable, so we might get the wrong error here.  */
+      return NO;
+    }
+
+  DGifCloseFile(file);
+  return YES;
+}
+
+
+#define SET_ERROR_MSG(msg) \
+   if (errorMsg != NULL) \
+     {\
+       *errorMsg = msg; \
+     }\
+   NSLog(msg);
+
+#define GIF_CREATE_ERROR(msg) \
+   SET_ERROR_MSG(msg); \
+   if (file != NULL) \
+     {\
+       DGifCloseFile(file); \
+     }\
+   if (imgBuffer != NULL) \
+     {\
+       NSZoneFree([self zone], imgBuffer); \
+     }\
+   RELEASE(self); \
+   return nil;
+
+#define CALL_CHECKED(f, where) \
+   gifrc = f; \
+   if (gifrc != GIF_OK) \
+     {\
+       NSString* msg = [NSString stringWithFormat: @"reading gif failed (%@)", \
+						   where]; \
+       GIF_CREATE_ERROR(msg);\
+     }
+
+/* Read a gif image. Assume it is from a gif file. */
+- (id) _initBitmapFromGIF: (NSData *)imageData
+	     errorMessage: (NSString **)errorMsg
+{
+  struct gs_gif_input_src src;
+  GifFileType            *file = NULL;
+  GifRecordType           recordType;
+  GifByteType            *extension;
+  GifPixelType           *imgBuffer = NULL;
+  GifPixelType           *imgBufferPos;  /* a position inside imgBuffer */
+  unsigned char          *rgbBuffer; /* image convertet to rgb */
+  unsigned                rgbBufferPos;
+  unsigned                rgbBufferSize;
+  ColorMapObject         *colorMap;
+  GifColorType           *color;
+  unsigned                pixelSize, rowSize;
+  int                     extCode;
+  int                     gifrc; /* required by CALL_CHECKED */
+  int                     i, j;  /* counters */
+  int                     imgHeight = 0, imgWidth = 0, imgRow = 0, imgCol = 0;
+
+  /* open the image */
+  gs_gif_init_input_source(&src, imageData);
+  file = DGifOpen(&src, gs_gif_input);
+  if (file == NULL)
+    {
+      /* we do not use giferror here because it doesn't
+         seem to be thread-safe (the error code is a global
+         variable, so we might get the wrong error here.  */
+      GIF_CREATE_ERROR(@"unable to open gif from data");
+      /* Not reached. */
+    }
+
+
+  /* allocate a buffer for the decoded image */
+  pixelSize = sizeof(GifPixelType);
+  rowSize   = file->SWidth * pixelSize;
+  imgBuffer = NSZoneMalloc([self zone], file->SHeight * rowSize);
+  if (imgBuffer == NULL)
+    {
+      GIF_CREATE_ERROR(@"could not allocate input buffer");
+      /* Not reached. */
+    }
+
+
+  /* set the background color */
+  memset(imgBuffer, file->SBackGroundColor, file->SHeight * rowSize);
+
+
+  /* read the image */
+  do
+    {
+      CALL_CHECKED(DGifGetRecordType(file, &recordType), @"GetRecordType");
+      switch (recordType)
+	{
+	  case IMAGE_DESC_RECORD_TYPE:
+	    {
+	      CALL_CHECKED(DGifGetImageDesc(file), @"GetImageDesc");
+	     
+	      imgWidth  = file->Image.Width;
+	      imgHeight = file->Image.Height;
+	      imgRow    = file->Image.Top;
+	      imgCol    = file->Image.Left;
+
+	      if ((file->Image.Left + file->Image.Width > file->SWidth)
+		  || (file->Image.Top + file->Image.Height > file->SHeight))
+		{
+		   GIF_CREATE_ERROR(@"image does not fit into screen dimensions");
+		}
+
+	      if (file->Image.Interlace)
+		{
+		  for (i = 0; i < 4; i++)
+		    {
+		      for (j = imgRow + InterlaceOffset[i]; j < imgRow + imgHeight;
+			   j = j + InterlaceJumps[i])
+			{
+			  imgBufferPos =
+			    imgBuffer + (j * rowSize) + (imgCol * pixelSize);
+			  CALL_CHECKED(DGifGetLine(file, imgBufferPos, imgWidth),
+				       @"GetLine(Interlaced)");
+			}      
+		    }
+		}
+	      else
+		{
+		  for (i = 0; i < imgHeight; i++)
+		    {
+		      imgBufferPos =
+			imgBuffer + ((imgRow++) * rowSize) + (imgCol * pixelSize);
+		      CALL_CHECKED(DGifGetLine(file, imgBufferPos, imgWidth),
+				   @"GetLine(Non-Interlaced)");
+		    }
+		}
+
+	      break;
+	    }
+
+	  case EXTENSION_RECORD_TYPE:
+	    {
+	      /* ignore extensions */
+	      CALL_CHECKED(DGifGetExtension(file, &extCode, &extension), @"GetExtension");
+	      while (extension != NULL)
+		{
+		  CALL_CHECKED(DGifGetExtensionNext(file, &extension), @"GetExtensionNext");
+		}
+	      break;
+	    }
+
+	  case TERMINATE_RECORD_TYPE:
+	  default:
+	    {
+	      break;
+	    }
+	}
+    } while (recordType != TERMINATE_RECORD_TYPE);
+
+
+  /* convert the image to rgb */
+  rgbBufferSize = file->SHeight * (file->SWidth * sizeof(unsigned char) * 3);
+  rgbBuffer = NSZoneMalloc([self zone],  rgbBufferSize);
+  if (rgbBuffer == NULL)
+    {
+      GIF_CREATE_ERROR(@"could not allocate image buffer");
+      /* Not reached. */
+    }
+
+  colorMap = (file->Image.ColorMap ? file->Image.ColorMap : file->SColorMap);
+  rgbBufferPos = 0;
+
+  for (i = 0; i < file->SHeight; i++)
+    {
+      imgBufferPos = imgBuffer + (i * rowSize);
+      for (j = 0; j < file->SWidth; j++)
+	{
+	  color = &colorMap->Colors[*(imgBufferPos + (j * pixelSize))];
+	  rgbBuffer[rgbBufferPos++] = color->Red;
+	  rgbBuffer[rgbBufferPos++] = color->Green;
+	  rgbBuffer[rgbBufferPos++] = color->Blue;
+	}
+    }
+
+  NSZoneFree([self zone], imgBuffer);
+
+
+  /* initialize self */
+  [self initWithBitmapDataPlanes: &rgbBuffer
+	pixelsWide: file->SWidth
+	pixelsHigh: file->SHeight
+	bitsPerSample: 8
+	samplesPerPixel: 3
+	hasAlpha: NO
+	isPlanar: NO
+	colorSpaceName: NSCalibratedRGBColorSpace
+	bytesPerRow: file->SWidth * 3
+	bitsPerPixel: 8 * 3];
+
+  _imageData = [[NSData alloc] initWithBytesNoCopy: rgbBuffer
+			       length: rgbBufferSize];
+   
+
+  /* don't forget to close the gif */
+  DGifCloseFile(file);
+
+  return self;
+}
+
+@end
+
+#else /* !HAVE_LIBUNGIF */
+
+@implementation NSBitmapImageRep (GIFReading)
++ (BOOL) _bitmapIsGIF: (NSData *)imageData
+{
+  return NO;
+}
+- (id) _initBitmapFromGIF: (NSData *)imageData
+	     errorMessage: (NSString **)errorMsg
+{
+  RELEASE(self);
+  return nil;
+}
+@end
+
+#endif /* !HAVE_LIBUNGIF */
+

Source/NSBitmapImageRep.m

@@ -32,6 +32,7 @@
 
 #include "AppKit/NSBitmapImageRep.h"
 
+#include "NSBitmapImageRep+GIF.h"
 #include "NSBitmapImageRep+JPEG.h"
 #include "NSBitmapImageRep+PNG.h"
 #include "NSBitmapImageRep+PNM.h"
@@ -108,6 +109,9 @@ static BOOL supports_lzw_compression = NO;
   if ([self _bitmapIsJPEG: data])
     return YES;
 
+  if ([self _bitmapIsGIF: data])
+    return YES;
+
   image = NSTiffOpenDataRead ((char *)[data bytes], [data length]);
 
   if (image != NULL)
@@ -134,6 +138,9 @@ static BOOL supports_lzw_compression = NO;
       types = [[NSMutableArray alloc] initWithObjects:
 	@"tiff", @"tif",
 	@"pnm", @"ppm",
+#if HAVE_LIBUNGIF
+	@"gif",
+#endif
 #if HAVE_LIBJPEG
 	@"jpeg", @"jpg",
 #endif
@@ -235,6 +242,20 @@ static BOOL supports_lzw_compression = NO;
       return a;
     }
 
+  if ([self _bitmapIsGIF: imageData])
+    {
+      NSBitmapImageRep *rep;
+      NSArray *a;
+
+      rep=[[self alloc] _initBitmapFromGIF: imageData
+			      errorMessage: NULL];
+      if (!rep)
+        return [NSArray array];
+      a = [NSArray arrayWithObject: rep];
+      DESTROY(rep);
+      return a;
+    }
+
   image = NSTiffOpenDataRead((char *)[imageData bytes], [imageData length]);
   if (image == NULL)
     {
@@ -282,6 +303,10 @@ static BOOL supports_lzw_compression = NO;
     return [self _initBitmapFromJPEG: imageData
 			errorMessage: NULL];
 
+  if ([isa _bitmapIsGIF: imageData])
+    return [self _initBitmapFromGIF: imageData
+		       errorMessage: NULL];
+
 
   image = NSTiffOpenDataRead((char *)[imageData bytes], [imageData length]);
   if (image == NULL)

configure

@@ -3589,6 +3589,72 @@ echo "$as_me: error: libpng not found." >&2;}
   fi
 fi
 
+
+echo "$as_me:$LINENO: checking for DGifOpen in -lungif" >&5
+echo $ECHO_N "checking for DGifOpen in -lungif... $ECHO_C" >&6
+if test "${ac_cv_lib_ungif_DGifOpen+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lungif  $LIBS"
+cat >conftest.$ac_ext <<_ACEOF
+#line $LINENO "configure"
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+/* Override any gcc2 internal prototype to avoid an error.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+/* We use char because int might match the return type of a gcc2
+   builtin and then its argument prototype would still apply.  */
+char DGifOpen ();
+int
+main ()
+{
+DGifOpen ();
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
+  (eval $ac_link) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+         { ac_try='test -s conftest$ac_exeext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  ac_cv_lib_ungif_DGifOpen=yes
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+ac_cv_lib_ungif_DGifOpen=no
+fi
+rm -f conftest.$ac_objext conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+echo "$as_me:$LINENO: result: $ac_cv_lib_ungif_DGifOpen" >&5
+echo "${ECHO_T}$ac_cv_lib_ungif_DGifOpen" >&6
+if test $ac_cv_lib_ungif_DGifOpen = yes; then
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_LIBUNGIF 1
+_ACEOF
+
+  LIBS="-lungif $LIBS"
+
+fi
+
+
+
 #--------------------------------------------------------------------
 # NSSound
 #--------------------------------------------------------------------

configure.ac

@@ -191,6 +191,9 @@ if test $enable_png = yes; then
   fi
 fi
 
+AC_CHECK_LIB(ungif, DGifOpen)
+
+
 #--------------------------------------------------------------------
 # NSSound
 #--------------------------------------------------------------------