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- /////////////////////////////////////////////////////////////////////////////
- // Name: imagjpeg.cpp
- // Purpose: wxImage JPEG handler
- // Author: Vaclav Slavik
- // RCS-ID: $Id: imagjpeg.cpp,v 1.30 2002/05/22 23:14:47 VZ Exp $
- // Copyright: (c) Vaclav Slavik
- // Licence: wxWindows licence
- /////////////////////////////////////////////////////////////////////////////
-
- #ifdef __GNUG__
- #pragma implementation "imagjpeg.h"
- #endif
-
- // For compilers that support precompilation, includes "wx.h".
- #include "wx/wxprec.h"
-
- #ifdef __BORLANDC__
- #pragma hdrstop
- #endif
-
- #include "wx/defs.h"
-
- #if wxUSE_IMAGE && wxUSE_LIBJPEG
-
- #include "wx/imagjpeg.h"
- #include "wx/bitmap.h"
- #include "wx/debug.h"
- #include "wx/log.h"
- #include "wx/app.h"
-
- // NB: Some compilers define boolean type in Windows headers (e.g. Watcom C++).
- // This causes a conflict with jmorecfg.h header from libjpeg, so we have
- // to make sure libjpeg won't try to define boolean itself. This is done by
- // defining HAVE_BOOLEAN.
- #if defined(__WXMSW__) && (defined(__MWERKS__) || defined(__WATCOMC__))
- #define HAVE_BOOLEAN
- #include <windows.h>
- #endif
-
- extern "C"
- {
- #include "jpeglib.h"
- }
-
- #include "wx/filefn.h"
- #include "wx/wfstream.h"
- #include "wx/intl.h"
- #include "wx/module.h"
-
- // For memcpy
- #include <string.h>
- // For JPEG library error handling
- #include <setjmp.h>
-
- #ifdef __SALFORDC__
- #undef FAR
- #endif
-
- // ----------------------------------------------------------------------------
- // types
- // ----------------------------------------------------------------------------
-
- // the standard definition of METHODDEF(type) from jmorecfg.h is "static type"
- // which means that we can't declare the method functions as extern "C" - the
- // compiler (rightfully) complains about the multiple storage classes in
- // declaration
- //
- // so we only add extern "C" when using our own, modified, jmorecfg.h - and use
- // whatever we have in the system headers if this is what we use hoping that it
- // should be ok (can't do anything else)
- #ifdef JPEG_METHOD_LINKAGE
- #define CPP_METHODDEF(type) extern "C" METHODDEF(type)
- #else // not using our jmorecfg.h header
- #define CPP_METHODDEF(type) METHODDEF(type)
- #endif
-
- //-----------------------------------------------------------------------------
- // wxJPEGHandler
- //-----------------------------------------------------------------------------
-
- IMPLEMENT_DYNAMIC_CLASS(wxJPEGHandler,wxImageHandler)
-
- #if wxUSE_STREAMS
-
- //------------- JPEG Data Source Manager
-
- #define JPEG_IO_BUFFER_SIZE 2048
-
- typedef struct {
- struct jpeg_source_mgr pub; /* public fields */
-
- JOCTET* buffer; /* start of buffer */
- wxInputStream *stream;
- } my_source_mgr;
-
- typedef my_source_mgr * my_src_ptr;
-
- CPP_METHODDEF(void) my_init_source ( j_decompress_ptr WXUNUSED(cinfo) )
- {
- }
-
- CPP_METHODDEF(boolean) my_fill_input_buffer ( j_decompress_ptr cinfo )
- {
- my_src_ptr src = (my_src_ptr) cinfo->src;
-
- src->pub.next_input_byte = src->buffer;
- src->pub.bytes_in_buffer = src->stream->Read(src->buffer, JPEG_IO_BUFFER_SIZE).LastRead();
-
- if (src->pub.bytes_in_buffer == 0) // check for end-of-stream
- {
- // Insert a fake EOI marker
- src->buffer[0] = 0xFF;
- src->buffer[1] = JPEG_EOI;
- src->pub.bytes_in_buffer = 2;
- }
- return TRUE;
- }
-
- CPP_METHODDEF(void) my_skip_input_data ( j_decompress_ptr cinfo, long num_bytes )
- {
- if (num_bytes > 0)
- {
- my_src_ptr src = (my_src_ptr) cinfo->src;
-
- while (num_bytes > (long)src->pub.bytes_in_buffer)
- {
- num_bytes -= (long) src->pub.bytes_in_buffer;
- src->pub.fill_input_buffer(cinfo);
- }
- src->pub.next_input_byte += (size_t) num_bytes;
- src->pub.bytes_in_buffer -= (size_t) num_bytes;
- }
- }
-
- CPP_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(-(long)src->pub.bytes_in_buffer, wxFromCurrent);
- delete[] src->buffer;
- }
-
-
- // JPEG error manager:
-
- struct my_error_mgr {
- struct jpeg_error_mgr pub; /* "public" fields */
-
- jmp_buf setjmp_buffer; /* for return to caller */
- };
-
- typedef struct my_error_mgr * my_error_ptr;
-
- /*
- * Here's the routine that will replace the standard error_exit method:
- */
-
- CPP_METHODDEF(void) my_error_exit (j_common_ptr cinfo)
- {
- /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
- my_error_ptr myerr = (my_error_ptr) cinfo->err;
-
- /* Always display the message. */
- /* We could postpone this until after returning, if we chose. */
- if (cinfo->err->output_message) (*cinfo->err->output_message) (cinfo);
-
- /* Return control to the setjmp point */
- longjmp(myerr->setjmp_buffer, 1);
- }
-
- void jpeg_wxio_src( j_decompress_ptr cinfo, wxInputStream& infile )
- {
- my_src_ptr src;
-
- if (cinfo->src == NULL) { /* first time for this JPEG object? */
- cinfo->src = (struct jpeg_source_mgr *)
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
- sizeof(my_source_mgr));
- src = (my_src_ptr) cinfo->src;
- }
- src = (my_src_ptr) cinfo->src;
- src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */
- src->buffer = new JOCTET[JPEG_IO_BUFFER_SIZE];
- src->pub.next_input_byte = NULL; /* until buffer loaded */
- src->stream = &infile;
-
- src->pub.init_source = my_init_source;
- src->pub.fill_input_buffer = my_fill_input_buffer;
- src->pub.skip_input_data = my_skip_input_data;
- src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */
- src->pub.term_source = my_term_source;
- }
-
-
- // 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) )
- {
- struct jpeg_decompress_struct cinfo;
- struct my_error_mgr jerr;
- JSAMPARRAY tempbuf;
- unsigned char *ptr;
- unsigned stride;
-
- image->Destroy();
- cinfo.err = jpeg_std_error( &jerr.pub );
- jerr.pub.error_exit = my_error_exit;
-
- if (!verbose) cinfo.err->output_message=NULL;
-
- /* Establish the setjmp return context for my_error_exit to use. */
- 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)
- wxLogError(_("JPEG: Couldn't load - file is probably corrupted."));
- (cinfo.src->term_source)(&cinfo);
- jpeg_destroy_decompress(&cinfo);
- if (image->Ok()) image->Destroy();
- return FALSE;
- }
-
- jpeg_create_decompress( &cinfo );
- jpeg_wxio_src( &cinfo, stream );
- jpeg_read_header( &cinfo, TRUE );
- cinfo.out_color_space = JCS_RGB;
- jpeg_start_decompress( &cinfo );
-
- image->Create( cinfo.image_width, cinfo.image_height );
- if (!image->Ok()) {
- jpeg_finish_decompress( &cinfo );
- jpeg_destroy_decompress( &cinfo );
- return FALSE;
- }
- image->SetMask( FALSE );
- ptr = image->GetData();
- stride = cinfo.output_width * 3;
- tempbuf = (*cinfo.mem->alloc_sarray)
- ((j_common_ptr) &cinfo, JPOOL_IMAGE, stride, 1 );
-
- while ( cinfo.output_scanline < cinfo.output_height ) {
- jpeg_read_scanlines( &cinfo, tempbuf, 1 );
- memcpy( ptr, tempbuf[0], stride );
- ptr += stride;
- }
- jpeg_finish_decompress( &cinfo );
- jpeg_destroy_decompress( &cinfo );
- return TRUE;
- }
-
- typedef struct {
- struct jpeg_destination_mgr pub;
-
- wxOutputStream *stream;
- JOCTET * buffer;
- } my_destination_mgr;
-
- typedef my_destination_mgr * my_dest_ptr;
-
- #define OUTPUT_BUF_SIZE 4096 /* choose an efficiently fwrite'able size */
-
- CPP_METHODDEF(void) init_destination (j_compress_ptr cinfo)
- {
- my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
-
- /* Allocate the output buffer --- it will be released when done with image */
- dest->buffer = (JOCTET *)
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
- OUTPUT_BUF_SIZE * sizeof(JOCTET));
- dest->pub.next_output_byte = dest->buffer;
- dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
- }
-
- CPP_METHODDEF(boolean) empty_output_buffer (j_compress_ptr cinfo)
- {
- my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
-
- dest->stream->Write(dest->buffer, OUTPUT_BUF_SIZE);
- dest->pub.next_output_byte = dest->buffer;
- dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
- return TRUE;
- }
-
- CPP_METHODDEF(void) term_destination (j_compress_ptr cinfo)
- {
- my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
- size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
- /* Write any data remaining in the buffer */
- if (datacount > 0)
- dest->stream->Write(dest->buffer, datacount);
- }
-
- GLOBAL(void) jpeg_wxio_dest (j_compress_ptr cinfo, wxOutputStream& outfile)
- {
- my_dest_ptr dest;
-
- if (cinfo->dest == NULL) { /* first time for this JPEG object? */
- cinfo->dest = (struct jpeg_destination_mgr *)
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
- sizeof(my_destination_mgr));
- }
-
- dest = (my_dest_ptr) cinfo->dest;
- dest->pub.init_destination = init_destination;
- dest->pub.empty_output_buffer = empty_output_buffer;
- dest->pub.term_destination = term_destination;
- dest->stream = &outfile;
- }
-
- bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose )
- {
- struct jpeg_compress_struct cinfo;
- struct my_error_mgr jerr;
- JSAMPROW row_pointer[1]; /* pointer to JSAMPLE row[s] */
- JSAMPLE *image_buffer;
- int stride; /* physical row width in image buffer */
-
- cinfo.err = jpeg_std_error(&jerr.pub);
- jerr.pub.error_exit = my_error_exit;
-
- if (!verbose) cinfo.err->output_message=NULL;
-
- /* Establish the setjmp return context for my_error_exit to use. */
- 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)
- wxLogError(_("JPEG: Couldn't save image."));
- jpeg_destroy_compress(&cinfo);
- return FALSE;
- }
-
- jpeg_create_compress(&cinfo);
- jpeg_wxio_dest(&cinfo, stream);
-
- cinfo.image_width = image->GetWidth();
- cinfo.image_height = image->GetHeight();
- 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 */
- image_buffer = image->GetData();
- while (cinfo.next_scanline < cinfo.image_height) {
- row_pointer[0] = &image_buffer[cinfo.next_scanline * stride];
- jpeg_write_scanlines( &cinfo, row_pointer, 1 );
- }
- jpeg_finish_compress(&cinfo);
- jpeg_destroy_compress(&cinfo);
-
- return TRUE;
- }
-
- #ifdef __VISUALC__
- #pragma warning(default:4611)
- #endif /* VC++ */
-
- bool wxJPEGHandler::DoCanRead( wxInputStream& stream )
- {
- unsigned char hdr[2];
-
- if ( !stream.Read(hdr, WXSIZEOF(hdr)) )
- return FALSE;
-
- return hdr[0] == 0xFF && hdr[1] == 0xD8;
- }
-
- #endif // wxUSE_STREAMS
-
- #endif // wxUSE_LIBJPEG
-
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