Merge changes from CUPS 1.4svn-r7696.

[thirdparty/cups.git] / filter / image-jpeg.c

diff --git a/filter/image-jpeg.c b/filter/image-jpeg.c
index f15174f3ffc04d0b3356622bf8f179a9a39396dc..4710ab269bd60e2fa6304ad6bbe50aaf0bdadbb2 100644 (file)
--- a/filter/image-jpeg.c
+++ b/filter/image-jpeg.c
@@ -1,5 +1,5 @@
 /*
- * "$Id: image-jpeg.c 6649 2007-07-11 21:46:42Z mike $"
+ * "$Id: image-jpeg.c 7355 2008-02-28 20:49:40Z mike $"
  *
  *   JPEG image routines for the Common UNIX Printing System (CUPS).
  *
@@ -47,8 +47,8 @@ _cupsImageReadJPEG(
   struct jpeg_error_mgr        jerr;           /* Error handler info */
   cups_ib_t            *in,            /* Input pixels */
                        *out;           /* Output pixels */
-  char                 header[16];     /* Photoshop JPEG header */
-  int                  psjpeg;         /* Non-zero if Photoshop JPEG */
+  jpeg_saved_marker_ptr        marker;         /* Pointer to marker data */
+  int                  psjpeg = 0;     /* Non-zero if Photoshop CMYK JPEG */
   static const char    *cspaces[] =
                        {               /* JPEG colorspaces... */
                          "JCS_UNKNOWN",
@@ -60,24 +60,31 @@ _cupsImageReadJPEG(
                        };
 
 
- /*
-  * Read the first 16 bytes to determine if this is a Photoshop JPEG file...
-  */
-
-  fread(header, sizeof(header), 1, fp);
-  rewind(fp);
-
-  psjpeg = memcmp(header + 6, "Photoshop ", 10) == 0;
-
  /*
   * Read the JPEG header...
   */
 
   cinfo.err = jpeg_std_error(&jerr);
   jpeg_create_decompress(&cinfo);
+  jpeg_save_markers(&cinfo, JPEG_APP0 + 14, 0xffff); /* Adobe JPEG */
   jpeg_stdio_src(&cinfo, fp);
   jpeg_read_header(&cinfo, 1);
 
+ /*
+  * Parse any Adobe APPE data embedded in the JPEG file.  Since Adobe doesn't
+  * bother following standards, we have to invert the CMYK JPEG data written by
+  * Adobe apps...
+  */
+
+  for (marker = cinfo.marker_list; marker; marker = marker->next)
+    if (marker->marker == (JPEG_APP0 + 14) && marker->data_length >= 12 &&
+        !memcmp(marker->data, "Adobe", 5) && marker->data[11] == 2)
+    {
+      fputs("DEBUG: Adobe CMYK JPEG detected (inverting color values)\n",
+           stderr);
+      psjpeg = 1;
+    }
+
   cinfo.quantize_colors = 0;
 
   fprintf(stderr, "DEBUG: num_components = %d\n", cinfo.num_components);
@@ -311,5 +318,5 @@ _cupsImageReadJPEG(
 
 
 /*
- * End of "$Id: image-jpeg.c 6649 2007-07-11 21:46:42Z mike $".
+ * End of "$Id: image-jpeg.c 7355 2008-02-28 20:49:40Z mike $".
  */