diff --git a/MagickCore/colorspace.c b/MagickCore/colorspace.c
index f9bcf5d038..575b03deb3 100644
--- a/MagickCore/colorspace.c
+++ b/MagickCore/colorspace.c
@@ -1500,9 +1500,6 @@ MagickExport MagickBooleanType SetImageColorspace(Image *image,
 MagickExport MagickBooleanType SetImageGray(Image *image,
   ExceptionInfo *exception)
 {
-  const char
-    *value;
-
   ImageType
     type;
 
@@ -1514,9 +1511,6 @@ MagickExport MagickBooleanType SetImageGray(Image *image,
     return(MagickTrue);
   if (IssRGBCompatibleColorspace(image->colorspace) == MagickFalse)
     return(MagickFalse);
-  value=GetImageProperty(image,"colorspace:auto-grayscale",exception);
-  if (IsStringFalse(value) != MagickFalse)
-    return(MagickFalse);
   type=IdentifyImageGray(image,exception);
   if (type == UndefinedType)
     return(MagickFalse);
@@ -1557,26 +1551,24 @@ MagickExport MagickBooleanType SetImageGray(Image *image,
 MagickExport MagickBooleanType SetImageMonochrome(Image *image,
   ExceptionInfo *exception)
 {
-  const char
-    *value;
+  ImageType
+    type;
 
   assert(image != (Image *) NULL);
   assert(image->signature == MagickCoreSignature);
   if (image->debug != MagickFalse)
     (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
-  if (image->type == BilevelType)
+  if (IsImageMonochrome(image) != MagickFalse)
     return(MagickTrue);
   if (IssRGBCompatibleColorspace(image->colorspace) == MagickFalse)
     return(MagickFalse);
-  value=GetImageProperty(image,"colorspace:auto-grayscale",exception);
-  if (IsStringFalse(value) != MagickFalse)
-    return(MagickFalse);
-  if (IdentifyImageMonochrome(image,exception) == MagickFalse)
+  type=IdentifyImageMonochrome(image,exception);
+  if (type == UndefinedType)
     return(MagickFalse);
   image->colorspace=GRAYColorspace;
   if (SyncImagePixelCache((Image *) image,exception) == MagickFalse)
     return(MagickFalse);
-  image->type=BilevelType;
+  image->type=type;
   return(MagickTrue);
 }
 
diff --git a/coders/coders-private.h b/coders/coders-private.h
index 867ab7c74f..3ea8d4b35b 100644
--- a/coders/coders-private.h
+++ b/coders/coders-private.h
@@ -16,6 +16,10 @@
 #ifndef MAGICK_CODERS_PRIVATE_H
 #define MAGICK_CODERS_PRIVATE_H
 
+#include "MagickCore/attribute.h"
+#include "MagickCore/property.h"
+#include "MagickCore/string_.h"
+
 #define MagickCoderHeader(coder,offset,magic)  { coder, offset, \
   (const unsigned char *) (magic), sizeof(magic)-1 },
 
@@ -27,4 +31,22 @@ extern ModuleExport size_t \
 extern ModuleExport void \
   Unregister ## coder ## Image(void);
 
+static inline ImageType IdentifyImageCoderType(const Image *image,
+  ExceptionInfo *exception)
+{
+  const char
+    *value;
+
+  ImageType
+    type;
+
+  type=IdentifyImageType(image,exception);
+  if ((type != GrayscaleType) && (type != BilevelType))
+    return(type);
+  value=GetImageProperty(image,"colorspace:auto-grayscale",exception);
+  if (IsStringFalse(value) == MagickFalse)
+    return(type);
+  return(TrueColorType);
+}
+
 #endif
diff --git a/coders/jpeg.c b/coders/jpeg.c
index 02a2af21b1..9a65252639 100644
--- a/coders/jpeg.c
+++ b/coders/jpeg.c
@@ -85,6 +85,7 @@
 #include "MagickCore/utility.h"
 #include "MagickCore/xml-tree.h"
 #include "MagickCore/xml-tree-private.h"
+#include "coders/coders-private.h"
 #include <setjmp.h>
 #if defined(MAGICKCORE_JPEG_DELEGATE)
 #define JPEG_INTERNAL_OPTIONS
@@ -340,8 +341,8 @@ static void JPEGErrorHandler(j_common_ptr jpeg_info)
     (void) LogMagickEvent(CoderEvent,GetMagickModule(),
       "[%s] JPEG Trace: \"%s\"",image->filename,message);
   if (client_info->finished != MagickFalse)
-    (void) ThrowMagickException(exception,GetMagickModule(),CorruptImageWarning,
-      (char *) message,"`%s'",image->filename);
+    (void) ThrowMagickException(exception,GetMagickModule(),
+      CorruptImageWarning,(char *) message,"`%s'",image->filename);
   else
     (void) ThrowMagickException(exception,GetMagickModule(),CorruptImageError,
       (char *) message,"`%s'",image->filename);
@@ -2340,7 +2341,7 @@ static MagickBooleanType WriteJPEGImage_(const ImageInfo *image_info,
       (void) TransformImageColorspace(image,sRGBColorspace,exception);
       if (image_info->type == TrueColorType)
         break;
-      type=IdentifyImageType(image,exception);
+      type=IdentifyImageCoderType(image,exception);
       if ((type == GrayscaleType) || (type == BilevelType))
         {
           jpeg_info->input_components=1;
diff --git a/coders/json.c b/coders/json.c
index 27e929b4c3..c72cf2c0e1 100644
--- a/coders/json.c
+++ b/coders/json.c
@@ -74,6 +74,7 @@
 #include "MagickCore/utility.h"
 #include "MagickCore/version.h"
 #include "MagickCore/module.h"
+#include "coders/coders-private.h"
 
 /*
   Typedef declarations.
@@ -1039,7 +1040,7 @@ static MagickBooleanType EncodeImageAttributes(Image *image,FILE *file,
     }
   JSONFormatLocaleFile(file,"    \"units\": %s,\n",CommandOptionToMnemonic(
     MagickResolutionOptions,(ssize_t) image->units));
-  type=IdentifyImageType(image,exception);
+  type=IdentifyImageCoderType(image,exception);
   JSONFormatLocaleFile(file,"    \"type\": %s,\n",CommandOptionToMnemonic(
     MagickTypeOptions,(ssize_t) type));
   if (image->type != type)
diff --git a/coders/png.c b/coders/png.c
index ab554bb544..37518458a0 100644
--- a/coders/png.c
+++ b/coders/png.c
@@ -90,6 +90,7 @@
 #include "MagickCore/timer-private.h"
 #include "MagickCore/transform.h"
 #include "MagickCore/utility.h"
+#include "coders/coders-private.h"
 #if defined(MAGICKCORE_PNG_DELEGATE)
 
 /* Suppress libpng pedantic warnings that were added in
@@ -12884,7 +12885,7 @@ static MagickBooleanType WriteOneJNGImage(MngInfo *mng_info,
   if ((image_info->type != TrueColorAlphaType) &&
       (image_info->type != TrueColorType))
     {
-      ImageType type = IdentifyImageType(image,exception);
+      ImageType type = IdentifyImageCoderType(image,exception);
       if ((type == GrayscaleType) || (type == BilevelType))
         jng_color_type-=2;
     }
@@ -13667,7 +13668,7 @@ static MagickBooleanType WriteMNGImage(const ImageInfo *image_info,
 
         if (need_local_plte == 0)
           {
-            ImageType type = IdentifyImageType(image,exception);
+            ImageType type = IdentifyImageCoderType(image,exception);
             if ((type != GrayscaleType) && (type != BilevelType))
               all_images_are_gray=MagickFalse;
             mng_info->equal_palettes=PalettesAreEqual(image,next_image);
diff --git a/coders/pnm.c b/coders/pnm.c
index 331c73d6ce..f33143c49d 100644
--- a/coders/pnm.c
+++ b/coders/pnm.c
@@ -65,6 +65,7 @@
 #include "MagickCore/statistic.h"
 #include "MagickCore/string_.h"
 #include "MagickCore/string-private.h"
+#include "coders/coders-private.h"
 
 /*
   Typedef declarations.
@@ -1710,7 +1711,7 @@ static MagickBooleanType WritePNMImage(const ImageInfo *image_info,Image *image,
         format='F';
         if (image_info->type == TrueColorType)
           break;
-        if (IdentifyImageType(image,exception) == GrayscaleType)
+        if (IdentifyImageCoderType(image,exception) == GrayscaleType)
           format='f';
         break;
       }
@@ -1728,7 +1729,7 @@ static MagickBooleanType WritePNMImage(const ImageInfo *image_info,Image *image,
         format='H';
         if (image_info->type == TrueColorType)
           break;
-        if (IdentifyImageType(image,exception) == GrayscaleType)
+        if (IdentifyImageCoderType(image,exception) == GrayscaleType)
           format='h';
         break;
       }
@@ -1741,7 +1742,7 @@ static MagickBooleanType WritePNMImage(const ImageInfo *image_info,Image *image,
         format='6';
         if (image_info->type == TrueColorType)
           break;
-        type=IdentifyImageType(image,exception);
+        type=IdentifyImageCoderType(image,exception);
         if (type == GrayscaleType)
           {
             format='5';
diff --git a/coders/ps.c b/coders/ps.c
index 7f43a7e11b..e97fdc464a 100644
--- a/coders/ps.c
+++ b/coders/ps.c
@@ -79,6 +79,7 @@
 #include "MagickCore/transform.h"
 #include "MagickCore/utility.h"
 #include "coders/bytebuffer-private.h"
+#include "coders/coders-private.h"
 #include "coders/ghostscript-private.h"
 
 /*
@@ -1766,7 +1767,7 @@ static MagickBooleanType WritePSImage(const ImageInfo *image_info,Image *image,
     index=(Quantum) 0;
     x=0;
     if (image_info->type != TrueColorType)
-      type=IdentifyImageType(image,exception);
+      type=IdentifyImageCoderType(image,exception);
     if ((type == GrayscaleType) || (type == BilevelType))
       {
         if (type == GrayscaleType)
diff --git a/coders/tiff.c b/coders/tiff.c
index da44924a2e..246697f13b 100644
--- a/coders/tiff.c
+++ b/coders/tiff.c
@@ -87,7 +87,8 @@
 #include "MagickCore/thread_.h"
 #include "MagickCore/token.h"
 #include "MagickCore/utility.h"
-#include "psd-private.h"
+#include "coders/coders-private.h"
+#include "coders/psd-private.h"
 #if defined(MAGICKCORE_TIFF_DELEGATE)
 # if defined(MAGICKCORE_HAVE_TIFFCONF_H)
 #  include <tiffconf.h>
@@ -3595,7 +3596,7 @@ static MagickBooleanType WriteTIFFImage(const ImageInfo *image_info,
             ImageType
               type;
 
-            type=IdentifyImageType(image,exception);
+            type=IdentifyImageCoderType(image,exception);
             if ((image_info->type != PaletteType) &&
                 ((type == GrayscaleType) || (type == BilevelType)))
               {
diff --git a/coders/xpm.c b/coders/xpm.c
index 172879163d..9c2e87985a 100644
--- a/coders/xpm.c
+++ b/coders/xpm.c
@@ -44,6 +44,7 @@
 #include "MagickCore/blob.h"
 #include "MagickCore/blob-private.h"
 #include "MagickCore/cache.h"
+#include "MagickCore/coder-private.h"
 #include "MagickCore/color.h"
 #include "MagickCore/color-private.h"
 #include "MagickCore/colormap.h"
@@ -70,6 +71,7 @@
 #include "MagickCore/module.h"
 #include "MagickCore/threshold.h"
 #include "MagickCore/utility.h"
+#include "coders/coders-private.h"
 
 /*
   Global declarations.
@@ -730,7 +732,7 @@ static MagickBooleanType WritePICONImage(const ImageInfo *image_info,
   blob_info=CloneImageInfo(image_info);
   *blob_info->magick='\0';
   (void) AcquireUniqueFilename(blob_info->filename);
-  type=IdentifyImageType(image,exception);
+  type=IdentifyImageCoderType(image,exception);
   if ((image_info->type != TrueColorType) &&
       ((type == GrayscaleType) || (type == BilevelType)))
     affinity_image=BlobToImage(blob_info,Graymap,GraymapExtent,exception);
diff --git a/coders/yaml.c b/coders/yaml.c
index d68cfc025b..08f0b7fcda 100644
--- a/coders/yaml.c
+++ b/coders/yaml.c
@@ -74,6 +74,7 @@
 #include "MagickCore/utility.h"
 #include "MagickCore/version.h"
 #include "MagickCore/module.h"
+#include "coders/coders-private.h"
 
 /*
   Typedef declarations.
@@ -1037,7 +1038,7 @@ static MagickBooleanType EncodeImageAttributes(Image *image,FILE *file,
     }
   YAMLFormatLocaleFile(file,"    units: %s\n",CommandOptionToMnemonic(
     MagickResolutionOptions,(ssize_t) image->units));
-  type=IdentifyImageType(image,exception);
+  type=IdentifyImageCoderType(image,exception);
   YAMLFormatLocaleFile(file,"    type: %s\n",CommandOptionToMnemonic(
     MagickTypeOptions,(ssize_t) type));
   if (image->type != type)