jpgdest.cpp

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// $Id: jpgdest.cpp 1282 2006-06-09 09:46:49Z alex $
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 */
// 


#include "camtypes.h"
//#include "ccfile.h" - in camtypes.h [AUTOMATICALLY REMOVED]

//#include "jinclude.h"
#include "jpglib_namespace.h"
#include "jpgermgr.h"

//#include "errors.h" - in camtypes.h [AUTOMATICALLY REMOVED]
//#include "tim.h"          // for _R(IDE_FILE_WRITE_ERROR)

#include "jpgdest.h"


// Place any IMPLEMENT type statements here
CC_IMPLEMENT_MEMDUMP(JPEGDataDestination, CC_CLASS_MEMDUMP)


// We want better memory tracking
#define new CAM_DEBUG_NEW


// Functions follow



/********************************************************************************************

>   JPEGDataDestination::JPEGDataDestination(j_compress_ptr cinfo, CCFile* pOutputFile)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    29/10/96
    Inputs:     pOutputFile : a pointer to a CCFile providing the destination for the JPEG
                output
    Purpose:    Default constructor

********************************************************************************************/
JPEGDataDestination::JPEGDataDestination(CCFile* pOutputFile)
{
    ERROR3IF(pOutputFile == NULL || !pOutputFile->IS_KIND_OF(CCFile), "pOutputFile isn't");


    m_DestMgr.pThis = this;

    m_DestMgr.init_destination      = InitDestination;
    m_DestMgr.empty_output_buffer   = EmptyOutputBuffer;
    m_DestMgr.term_destination      = TerminateDestination;

    m_pOutputFile   = pOutputFile;
    m_pBuffer       = NULL;
}


/********************************************************************************************

>   BOOL JPEGDataDestination::Init(j_compress_ptr cinfo)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    29/10/96
    Inputs:     cinfo : a pointer to the IJG compression structure
    Purpose:    Initializes the given compression structure with this JPEGDataDestination

********************************************************************************************/
BOOL JPEGDataDestination::Init(libJPEG::j_compress_ptr cinfo)
{
    ERROR3IF(cinfo == NULL, "cinfo NULL");

    cinfo->dest = &m_DestMgr;

    return TRUE;
}


/********************************************************************************************

>   void JPEGDataDestination::InitDestination(j_compress_ptr cinfo)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    29/10/96
    Inputs:     cinfo : a pointer to the IJG compression control structure
    Purpose:    Callback for IJG destination file handler
                Initialize destination --- called by jpeg_start_compress
                before any data is actually written.

********************************************************************************************/
void JPEGDataDestination::InitDestination(libJPEG::j_compress_ptr cinfo)
{
    using namespace libJPEG;

    JPEGDataDestination* pThis = GetThis(cinfo);

    /* Allocate the output buffer --- it will be released when done with image */
    pThis->m_pBuffer = (JOCTET *)(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                  OUTPUT_BUF_SIZE * sizeof(JOCTET));

    pThis->m_DestMgr.next_output_byte = pThis->m_pBuffer;
    pThis->m_DestMgr.free_in_buffer = OUTPUT_BUF_SIZE;
}


/********************************************************************************************

>   boolean JPEGDataDestination::EmptyOutputBuffer(j_compress_ptr cinfo)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    29/10/96
    Inputs:     cinfo : a pointer to the IJG compression control structure
    Purpose:    Callback for IJG destination file handler
                Empty the output buffer --- called whenever buffer fills up.
    Notes:      Says IJG docs,
                "In typical applications, this should write the entire output buffer
                (ignoring the current state of next_output_byte & free_in_buffer),
                reset the pointer & count to the start of the buffer, and return TRUE
                indicating that the buffer has been dumped."
    Scope:      static

********************************************************************************************/
libJPEG::boolean    JPEGDataDestination::EmptyOutputBuffer(libJPEG::j_compress_ptr cinfo)
{
    JPEGDataDestination* pThis = GetThis(cinfo);
    CCFile* pFile = pThis->GetFile();

    // Write out the full buffer
    pFile->write(pThis->m_pBuffer, OUTPUT_BUF_SIZE);

    // Check written OK
    if (pFile->bad() || pFile->fail())
    {
        JPEGErrorManager* pError = (JPEGErrorManager*)cinfo->err;
        pError->ThrowError(_R(IDE_FILE_WRITE_ERROR));
    }

    pThis->m_DestMgr.next_output_byte   = pThis->m_pBuffer;
    pThis->m_DestMgr.free_in_buffer = OUTPUT_BUF_SIZE;

  return TRUE;
}


/********************************************************************************************

>   void JPEGDataDestination::TerminateDestination(j_compress_ptr cinfo)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    29/10/96
    Inputs:     cinfo : a pointer to the IJG compression control structure
    Purpose:    Terminate destination --- called by jpeg_finish_compress
                after all data has been written.  Usually needs to flush buffer.
    Notes:      *not* called by jpeg_abort or jpeg_destroy; surrounding
                application must deal with any cleanup that should happen even
                for error exit.

********************************************************************************************/
void JPEGDataDestination::TerminateDestination(libJPEG::j_compress_ptr cinfo)
{
    JPEGDataDestination* pThis = GetThis(cinfo);
    CCFile* pFile = pThis->GetFile();

    size_t DataCount = OUTPUT_BUF_SIZE - pThis->m_DestMgr.free_in_buffer;

    // Write any data remaining in the buffer
    if (DataCount > 0)
    {
        // Write out the full buffer
        pFile->write(pThis->m_pBuffer, DataCount);
    }
    pFile->flush();

    // Make sure we wrote the output file OK
    if (pFile->bad() || pFile->fail())
    {
        JPEGErrorManager* pError = (JPEGErrorManager*)cinfo->err;
        pError->ThrowError(_R(IDE_FILE_WRITE_ERROR));
    }
}



/********************************************************************************************

>   JPEGDataDestination* JPEGDataDestination::GetThis(j_compress_ptr cinfo)

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    29/10/96
    Inputs:     cinfo : a pointer to the IJG compression control structure
    Purpose:    Helper function to return the this pointer buried in the cinfo structure

********************************************************************************************/
JPEGDataDestination* JPEGDataDestination::GetThis(libJPEG::j_compress_ptr cinfo)
{
    JPEGDataDestination* pThis = ((IJGDestMgr*)(cinfo->dest))->pThis;
    ERROR3IF(!pThis->IS_KIND_OF(JPEGDataDestination), "GetThis - pThis isn't");

    return pThis;
}


/********************************************************************************************

>   CCFile* JPEGDataDestination::GetFile() const

    Author:     Colin_Barfoot (Xara Group Ltd) <camelotdev@xara.com>
    Created:    29/10/96
    Purpose:    Helper function to return the CCFile associated with this JPEGDataDestination

********************************************************************************************/
CCFile* JPEGDataDestination::GetFile() const
{
    return m_pOutputFile;
}

---