ossimJpegMemSrc.h File Reference

#include <ossim/base/ossimConstants.h>
#include <cstdlib>

Go to the source code of this file.

Functions
OSSIM_DLL void	ossimJpegErrorExit (jpeg_common_struct *cinfo)
	Error routine that will replace jpeg's standard error_exit method. More...
OSSIM_DLL void	ossimJpegMemorySrc (jpeg_decompress_struct *cinfo, const ossim_uint8 *buffer, std::size_t bufsize)
	Method which uses memory instead of a FILE* to read from. More...

Function Documentation

ossimJpegErrorExit()

OSSIM_DLL void ossimJpegErrorExit

(

jpeg_common_struct *

cinfo

)

Error routine that will replace jpeg's standard error_exit method.

Definition at line 32 of file ossimJpegCodec.cpp.

References ossimJpegErrorMgr::setjmp_buffer.

Referenced by ossimJpegCodec::decodeJpeg(), and ossimJpegCodec::getColorSpace().

{
   /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
   ossimJpegErrorPtr myerr = (ossimJpegErrorPtr) cinfo->err;
   
   /* Always display the message. */
   /* We could postpone this until after returning, if we chose. */
   (*cinfo->err->output_message) (cinfo);
   
   /* Return control to the setjmp point */
   longjmp(myerr->setjmp_buffer, 1);
}

ossimJpegMemorySrc()

OSSIM_DLL void ossimJpegMemorySrc	(	jpeg_decompress_struct *	cinfo,
		const ossim_uint8 *	buffer,
		std::size_t	bufsize
	)

Method which uses memory instead of a FILE* to read from.

Note

Used in place of "jpeg_stdio_src(&cinfo, infile)".

"unsigned char = JOCTET

Definition at line 148 of file ossimJpegMemSrc.cpp.

References fill_input_buffer(), init_source(), ossimJpegSourceMgr::pub, skip_input_data(), and term_source().

Referenced by ossimJpegCodec::decodeJpeg(), and ossimJpegCodec::getColorSpace().

{
  ossimJpegSourceMgrPtr src;

  /* The source object is made permanent so that a series of JPEG images
   * can be read from a single buffer by calling jpeg_memory_src
   * only before the first one.
   * This makes it unsafe to use this manager and a different source
   * manager serially with the same JPEG object.  Caveat programmer.
   */
  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(ossimJpegSourceMgr));
  }

  src = (ossimJpegSourceMgrPtr) cinfo->src;
  src->pub.init_source = init_source;
  src->pub.fill_input_buffer = fill_input_buffer;
  src->pub.skip_input_data = skip_input_data;
  src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */
  src->pub.term_source = term_source;

  src->pub.next_input_byte = buffer;
  src->pub.bytes_in_buffer = bufsize;
}