don't annoy the user by repeating the question which had been already answered (and...

[wxWidgets.git] / src / common / imagjpeg.cpp

diff --git a/src/common/imagjpeg.cpp b/src/common/imagjpeg.cpp
index 3078d705288e2006bab51efa83ad825583855353..1e8457fc9b9a07f12613efb8a3ab81b453db8349 100644 (file)
--- a/src/common/imagjpeg.cpp
+++ b/src/common/imagjpeg.cpp
@@ -20,7 +20,7 @@
 
 #include "wx/defs.h"
 
-#if wxUSE_LIBJPEG
+#if wxUSE_IMAGE && wxUSE_LIBJPEG
 
 #include "wx/imagjpeg.h"
 #include "wx/bitmap.h"
@@ -99,7 +99,7 @@ METHODDEF(void) my_skip_input_data ( j_decompress_ptr cinfo, long num_bytes )
     {
         my_src_ptr src = (my_src_ptr) cinfo->src;
 
-        while (num_bytes > (long)src->pub.bytes_in_buffer) 
+        while (num_bytes > (long)src->pub.bytes_in_buffer)
         {
             num_bytes -= (long) src->pub.bytes_in_buffer;
             src->pub.fill_input_buffer(cinfo);
@@ -114,7 +114,7 @@ METHODDEF(void) my_term_source ( j_decompress_ptr cinfo )
     my_src_ptr src = (my_src_ptr) cinfo->src;
 
     if (src->pub.bytes_in_buffer > 0)
-        src->stream->SeekI(-src->pub.bytes_in_buffer, wxFromCurrent);
+        src->stream->SeekI(-(long)src->pub.bytes_in_buffer, wxFromCurrent);
     delete[] src->buffer;
 }
 
@@ -170,7 +170,11 @@ my_error_exit (j_common_ptr cinfo)
   longjmp(myerr->setjmp_buffer, 1);
 }
 
-
+// temporarily disable the warning C4611 (interaction between '_setjmp' and
+// C++ object destruction is non-portable) - I don't see any dtors here
+#ifdef __VISUALC__
+    #pragma warning(disable:4611)
+#endif /* VC++ */
 
 bool wxJPEGHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose, int WXUNUSED(index) )
 {
@@ -191,7 +195,7 @@ bool wxJPEGHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbos
       /* If we get here, the JPEG code has signaled an error.
        * We need to clean up the JPEG object, close the input file, and return.
        */
-      if (verbose) 
+      if (verbose)
         wxLogError(_("JPEG: Couldn't load - file is probably corrupted."));
       jpeg_destroy_decompress(&cinfo);
       if (image->Ok()) image->Destroy();
@@ -226,10 +230,6 @@ bool wxJPEGHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbos
     return TRUE;
 }
 
-
-
-
-
 typedef struct {
     struct jpeg_destination_mgr pub;
 
@@ -303,12 +303,12 @@ bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbo
     if (!verbose) cinfo.err->output_message=NULL;
 
     /* Establish the setjmp return context for my_error_exit to use. */
-    if (setjmp(jerr.setjmp_buffer)) 
+    if (setjmp(jerr.setjmp_buffer))
     {
         /* If we get here, the JPEG code has signaled an error.
          * We need to clean up the JPEG object, close the input file, and return.
          */
-         if (verbose) 
+         if (verbose)
             wxLogError(_("JPEG: Couldn't save image."));
          jpeg_destroy_compress(&cinfo);
          return FALSE;
@@ -322,6 +322,16 @@ bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbo
     cinfo.input_components = 3;
     cinfo.in_color_space = JCS_RGB;
     jpeg_set_defaults(&cinfo);
+
+    // TODO: 3rd parameter is force_baseline, what value should this be?
+    // Code says: "If force_baseline is TRUE, the computed quantization table entries
+    // are limited to 1..255 for JPEG baseline compatibility."
+    // 'Quality' is a number between 0 (terrible) and 100 (very good).
+    // The default (in jcparam.c, jpeg_set_defaults) is 75,
+    // and force_baseline is TRUE.
+    if (image->HasOption(wxT("quality")))
+        jpeg_set_quality(&cinfo, image->GetOptionInt(wxT("quality")), TRUE);
+
     jpeg_start_compress(&cinfo, TRUE);
 
     stride = cinfo.image_width * 3;    /* JSAMPLEs per row in image_buffer */
@@ -336,12 +346,15 @@ bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbo
     return TRUE;
 }
 
+#ifdef __VISUALC__
+    #pragma warning(default:4611)
+#endif /* VC++ */
 
 bool wxJPEGHandler::DoCanRead( wxInputStream& stream )
 {
     unsigned char hdr[2];
 
-    stream.Read(&hdr, 2);
+    stream.Read(hdr, 2);
     stream.SeekI(-2, wxFromCurrent);
     return (hdr[0] == 0xFF && hdr[1] == 0xD8);
 }