source: liacs/MIR2010/Sample/cximage/ximamng.cpp@ 93

/*
 * File:        ximamng.cpp
 * Purpose:     Platform Independent MNG Image Class Loader and Writer
 * Author:      07/Aug/2001 Davide Pizzolato - www.xdp.it
 * CxImage version 6.0.0 02/Feb/2008
 */

#include "ximamng.h"

#if CXIMAGE_SUPPORT_MNG

////////////////////////////////////////////////////////////////////////////////
// callbacks for the mng decoder:
////////////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////////////
// memory allocation; data must be zeroed
static mng_ptr
mymngalloc( mng_uint32 size )
{
        return (mng_ptr)calloc(1, size);
}

////////////////////////////////////////////////////////////////////////////////
// memory deallocation
static void mymngfree(mng_ptr p, mng_uint32 size)
{
        free(p);
}

////////////////////////////////////////////////////////////////////////////////
// Stream open/close:
// since the user is responsible for opening and closing the file,
// we leave the default implementation open
static mng_bool mymngopenstream(mng_handle mng)      { return MNG_TRUE; }
static mng_bool mymngopenstreamwrite(mng_handle mng) { return MNG_TRUE; }
static mng_bool mymngclosestream(mng_handle mng)     { return MNG_TRUE; }

////////////////////////////////////////////////////////////////////////////////
// feed data to the decoder
static mng_bool mymngreadstream(mng_handle mng, mng_ptr buffer, mng_uint32 size, mng_uint32 *bytesread)
{
        mngstuff *mymng = (mngstuff *)mng_get_userdata(mng);
        // read the requested amount of data from the file
        *bytesread = mymng->file->Read( buffer, sizeof(BYTE), size);
        return MNG_TRUE;
}

////////////////////////////////////////////////////////////////////////////////
static mng_bool mymngwritestream (mng_handle mng, mng_ptr pBuf, mng_uint32 iSize, mng_uint32 *iWritten)
{
        mngstuff *mymng = (mngstuff *)mng_get_userdata(mng);
        // write it
        *iWritten = mymng->file->Write (pBuf, 1, iSize);
        return MNG_TRUE;
}

////////////////////////////////////////////////////////////////////////////////
// the header's been read. set up the display stuff
static mng_bool mymngprocessheader( mng_handle mng, mng_uint32 width, mng_uint32 height )
{
        // normally the image buffer is allocated here,
        // but in this module we don't know nothing about
        // the final environment.

        mngstuff *mymng = (mngstuff *)mng_get_userdata(mng);
        
        mymng->width  = width;
        mymng->height = height;
        mymng->bpp    = 24;
        mymng->effwdt = ((((width * mymng->bpp) + 31) >> 5) << 2);

        if (mng->bUseBKGD){
                mymng->nBkgndIndex = 0;
                mymng->nBkgndColor.rgbRed  = mng->iBGred >> 8;
                mymng->nBkgndColor.rgbGreen =mng->iBGgreen >> 8;
                mymng->nBkgndColor.rgbBlue = mng->iBGblue >> 8;
        }

        mymng->image = (BYTE*)malloc(height * mymng->effwdt);

        // tell the mng decoder about our bit-depth choice
#if CXIMAGE_SUPPORT_ALPHA
        mng_set_canvasstyle( mng, MNG_CANVAS_RGB8_A8 );
        mymng->alpha = (BYTE*)malloc(height * width);
#else
        mng_set_canvasstyle( mng, MNG_CANVAS_BGR8);
        mymng->alpha = NULL;
#endif
        return MNG_TRUE;
}

////////////////////////////////////////////////////////////////////////////////
// return a row pointer for the decoder to fill
static mng_ptr mymnggetcanvasline( mng_handle mng, mng_uint32 line )
{
        mngstuff *mymng = (mngstuff *)mng_get_userdata(mng);
        return (mng_ptr)(mymng->image + (mymng->effwdt * (mymng->height - 1 - line)));
}
////////////////////////////////////////////////////////////////////////////////
// return a row pointer for the decoder to fill for alpha channel
static mng_ptr mymnggetalphaline( mng_handle mng, mng_uint32 line )
{
        mngstuff *mymng = (mngstuff *)mng_get_userdata(mng);
        return (mng_ptr)(mymng->alpha + (mymng->width * (mymng->height - 1 - line)));
}

////////////////////////////////////////////////////////////////////////////////
// timer
static mng_uint32 mymnggetticks(mng_handle mng)
{
#ifdef WIN32
        return (mng_uint32)GetTickCount();
#else
  return 0;
#endif
}

////////////////////////////////////////////////////////////////////////////////
// Refresh: actual frame need to be updated (Invalidate)
static mng_bool mymngrefresh(mng_handle mng, mng_uint32 x, mng_uint32 y, mng_uint32 w, mng_uint32 h)
{
//      mngstuff *mymng = (mngstuff *)mng_get_userdata(mng);
        return MNG_TRUE;
}

////////////////////////////////////////////////////////////////////////////////
// interframe delay callback
static mng_bool mymngsettimer(mng_handle mng, mng_uint32 msecs)
{
        mngstuff *mymng = (mngstuff *)mng_get_userdata(mng);
        mymng->delay = msecs;   // set the timer for when the decoder wants to be woken
        return MNG_TRUE;
}

////////////////////////////////////////////////////////////////////////////////
static mng_bool mymngerror(mng_handle mng, mng_int32 code, mng_int8 severity, mng_chunkid chunktype, mng_uint32 chunkseq, mng_int32 extra1, mng_int32 extra2, mng_pchar text)
{
        return mng_cleanup(&mng); //<Arkadiy Olovyannikov>
}

////////////////////////////////////////////////////////////////////////////////
// CxImage members
////////////////////////////////////////////////////////////////////////////////
CxImageMNG::CxImageMNG(): CxImage(CXIMAGE_FORMAT_MNG)
{
        hmng = NULL;
        memset(&mnginfo,0,sizeof(mngstuff));
        mnginfo.nBkgndIndex = -1;
        mnginfo.speed = 1.0f;
}
////////////////////////////////////////////////////////////////////////////////
CxImageMNG::~CxImageMNG()
{
        // cleanup and return
        if (mnginfo.thread){ //close the animation thread
                mnginfo.animation_enabled=0;
                ResumeThread(mnginfo.thread);
                WaitForSingleObject(mnginfo.thread,500);
                CloseHandle(mnginfo.thread);
        }
        // free objects
        if (mnginfo.image) free(mnginfo.image);
        if (mnginfo.alpha) free(mnginfo.alpha);
        if (hmng) mng_cleanup(&hmng); //be sure it's not needed any more. (active timers ?)
}
////////////////////////////////////////////////////////////////////////////////
void CxImageMNG::SetCallbacks(mng_handle mng)
{
        // set the callbacks
        mng_setcb_errorproc(mng, mymngerror);
        mng_setcb_openstream(mng, mymngopenstream);
        mng_setcb_closestream(mng, mymngclosestream);
        mng_setcb_readdata(mng, mymngreadstream);
        mng_setcb_processheader(mng, mymngprocessheader);
        mng_setcb_getcanvasline(mng, mymnggetcanvasline);
        mng_setcb_refresh(mng, mymngrefresh);
        mng_setcb_gettickcount(mng, mymnggetticks);
        mng_setcb_settimer(mng, mymngsettimer);
        mng_setcb_refresh(mng, mymngrefresh);
        mng_setcb_getalphaline(mng, mymnggetalphaline);
}
////////////////////////////////////////////////////////////////////////////////
// can't use the CxImage implementation because it looses mnginfo
bool CxImageMNG::Load(const TCHAR * imageFileName){
        FILE* hFile;    //file handle to read the image
#ifdef WIN32
        if ((hFile=_tfopen(imageFileName,_T("rb")))==NULL)  return false;       // For UNICODE support
#else
        if ((hFile=fopen(imageFileName,"rb"))==NULL)  return false;
#endif
        bool bOK = Decode(hFile);
        fclose(hFile);
        return bOK;
}
////////////////////////////////////////////////////////////////////////////////
#if CXIMAGE_SUPPORT_DECODE
////////////////////////////////////////////////////////////////////////////////
bool CxImageMNG::Decode(CxFile *hFile)
{
        if (hFile == NULL) return false;

        cx_try
        {
                // set up the mng decoder for our stream
                hmng = mng_initialize(&mnginfo, mymngalloc, mymngfree, MNG_NULL);
                if (hmng == NULL) cx_throw("could not initialize libmng");                      

                // set the file we want to play
                mnginfo.file = hFile;

                // Set the colorprofile, lcms uses this:
                mng_set_srgb(hmng, MNG_TRUE );
                // Set white as background color:
                WORD Red,Green,Blue;
                Red = Green = Blue = (255 << 8) + 255;
                mng_set_bgcolor(hmng, Red, Green, Blue );
                // If PNG Background is available, use it:
                mng_set_usebkgd(hmng, MNG_TRUE );

                // No need to store chunks:
                mng_set_storechunks(hmng, MNG_FALSE);
                // No need to wait: straight reading
                mng_set_suspensionmode(hmng, MNG_FALSE);

                SetCallbacks(hmng);

                mng_datap pData = (mng_datap)hmng;

                // read in the image
                info.nNumFrames=0;
                int retval=MNG_NOERROR;

                retval = mng_readdisplay(hmng);

                if (retval != MNG_NOERROR && retval != MNG_NEEDTIMERWAIT){
                        mng_store_error(hmng,retval,0,0);
                        if (hmng->zErrortext){
                                cx_throw(hmng->zErrortext);
                        } else {
                                cx_throw("Error in MNG file");
                        }
                }

                if (info.nEscape == -1) {
                        // Return output dimensions only
                        head.biWidth = hmng->iWidth;
                        head.biHeight = hmng->iHeight;
                        info.dwType = CXIMAGE_FORMAT_MNG;
                        return true;
                }

                // read all
                while(pData->bReading){
                        retval = mng_display_resume(hmng);
                        info.nNumFrames++;
                }

                // single frame check:
                if (retval != MNG_NEEDTIMERWAIT){
                        info.nNumFrames--;
                } else {
                        mnginfo.animation=1;
                }

                if (info.nNumFrames<=0) info.nNumFrames=1;

                if (mnginfo.animation_enabled==0){
                        // select the frame
                        if (info.nFrame>=0 && info.nFrame<info.nNumFrames){
                                for (int n=0;n<info.nFrame;n++) mng_display_resume(hmng);
                        } else cx_throw("Error: frame not present in MNG file");
                }

                if (mnginfo.nBkgndIndex >= 0){
                        info.nBkgndIndex = mnginfo.nBkgndIndex;
                        info.nBkgndColor.rgbRed = mnginfo.nBkgndColor.rgbRed;
                        info.nBkgndColor.rgbGreen = mnginfo.nBkgndColor.rgbGreen;
                        info.nBkgndColor.rgbBlue = mnginfo.nBkgndColor.rgbBlue;
                }

                //store the newly created image
                if (Create(mnginfo.width,mnginfo.height,mnginfo.bpp, CXIMAGE_FORMAT_MNG)){
                        memcpy(GetBits(), mnginfo.image, info.dwEffWidth * head.biHeight);
#if CXIMAGE_SUPPORT_ALPHA
                        SwapRGB2BGR();
                        AlphaCreate();
                        if(AlphaIsValid() && mnginfo.alpha){
                                memcpy(AlphaGetPointer(),mnginfo.alpha,mnginfo.width * mnginfo.height);
                        }
#endif
                } else cx_throw("CxImageMNG::Decode cannot create image");


        } cx_catch {
                if (strcmp(message,"")) strncpy(info.szLastError,message,255);
                return false;
        }
        return true;
}
////////////////////////////////////////////////////////////////////////////////
#endif //CXIMAGE_SUPPORT_DECODE
////////////////////////////////////////////////////////////////////////////////
#if CXIMAGE_SUPPORT_ENCODE
////////////////////////////////////////////////////////////////////////////////
bool CxImageMNG::Encode(CxFile *hFile)
{
        if (EncodeSafeCheck(hFile)) return false;

        cx_try
        {
                if (head.biClrUsed != 0) cx_throw("MNG encoder can save only RGB images");
                // set the file we want to play
                mnginfo.file = hFile;
                mnginfo.bpp = head.biBitCount;
                mnginfo.effwdt = info.dwEffWidth;
                mnginfo.height = head.biHeight;
                mnginfo.width =  head.biWidth;

                mnginfo.image = (BYTE*)malloc(head.biSizeImage);
                if (mnginfo.image == NULL) cx_throw("could not allocate memory for MNG");
                memcpy(mnginfo.image,info.pImage, head.biSizeImage);

                // set up the mng decoder for our stream
                hmng = mng_initialize(&mnginfo, mymngalloc, mymngfree, MNG_NULL);
                if (hmng == NULL) cx_throw("could not initialize libmng");                      

                mng_setcb_openstream(hmng, mymngopenstreamwrite );
                mng_setcb_closestream(hmng, mymngclosestream);
                mng_setcb_writedata(hmng, mymngwritestream);

                // Write File:
                mng_create(hmng);
                // Just a single Frame (save a normal PNG):
                WritePNG(hmng, 0, 1 );
                // Now write file:
                mng_write(hmng);

        } cx_catch {
                if (strcmp(message,"")) strncpy(info.szLastError,message,255);
                return false;
        }
        return true;
}
////////////////////////////////////////////////////////////////////////////////
// Writes a single PNG datastream
void CxImageMNG::WritePNG( mng_handle hMNG, int Frame, int FrameCount )
{
        mngstuff *mymng = (mngstuff *)mng_get_userdata(hMNG);
        
        int OffsetX=0,OffsetY=0,OffsetW=mymng->width,OffsetH=mymng->height;

        BYTE *tmpbuffer = new BYTE[ (mymng->effwdt+1) * mymng->height];
        if( tmpbuffer == 0 ) return;

        // Write DEFI chunk.
        mng_putchunk_defi( hMNG, 0, 0, 0, MNG_TRUE, OffsetX, OffsetY, MNG_FALSE, 0, 0, 0, 0 );
                 
        // Write Header:
        mng_putchunk_ihdr(
                hMNG, 
                OffsetW, OffsetH, 
                MNG_BITDEPTH_8, 
                MNG_COLORTYPE_RGB, 
                MNG_COMPRESSION_DEFLATE, 
                MNG_FILTER_ADAPTIVE, 
                MNG_INTERLACE_NONE 
        );

        // transfer data, add Filterbyte:
        for( int Row=0; Row<OffsetH; Row++ ){
                // First Byte in each Scanline is Filterbyte: Currently 0 -> No Filter.
                tmpbuffer[Row*(mymng->effwdt+1)]=0; 
                // Copy the scanline: (reverse order)
                memcpy(tmpbuffer+Row*(mymng->effwdt+1)+1, 
                        mymng->image+((OffsetH-1-(OffsetY+Row))*(mymng->effwdt))+OffsetX,mymng->effwdt);
                // swap red and blue components
                RGBtoBGR(tmpbuffer+Row*(mymng->effwdt+1)+1,mymng->effwdt);
        } 

        // Compress data with ZLib (Deflate):
        BYTE *dstbuffer = new BYTE[(mymng->effwdt+1)*OffsetH];
        if( dstbuffer == 0 ) return;
        DWORD dstbufferSize=(mymng->effwdt+1)*OffsetH;

        // Compress data:
        if(Z_OK != compress2((Bytef *)dstbuffer,(ULONG *)&dstbufferSize,(const Bytef*)tmpbuffer,
                                                (ULONG) (mymng->effwdt+1)*OffsetH,9 )) return;

        // Write Data into MNG File:
        mng_putchunk_idat( hMNG, dstbufferSize, (mng_ptr*)dstbuffer);
        mng_putchunk_iend(hMNG);

        // Free the stuff:
        delete [] tmpbuffer;
        delete [] dstbuffer;
}
////////////////////////////////////////////////////////////////////////////////
long CxImageMNG::Resume()
{
        if (MNG_NEEDTIMERWAIT == mng_display_resume(hmng)){
                if (info.pImage==NULL){
                        Create(mnginfo.width,mnginfo.height,mnginfo.bpp, CXIMAGE_FORMAT_MNG);
                }
                if (IsValid()){
                        memcpy(GetBits(), mnginfo.image, info.dwEffWidth * head.biHeight);
#if CXIMAGE_SUPPORT_ALPHA
                        SwapRGB2BGR();
                        AlphaCreate();
                        if(AlphaIsValid() && mnginfo.alpha){
                                memcpy(AlphaGetPointer(),mnginfo.alpha,mnginfo.width * mnginfo.height);
                        }
#endif
                }
        } else {
                mnginfo.animation_enabled = 0;
        }
        return mnginfo.animation_enabled;
}
////////////////////////////////////////////////////////////////////////////////
void CxImageMNG::SetSpeed(float speed)
{
        if (speed>10.0) mnginfo.speed = 10.0f;
        else if (speed<0.1) mnginfo.speed = 0.1f;
        else mnginfo.speed=speed;
}
////////////////////////////////////////////////////////////////////////////////
#endif //CXIMAGE_SUPPORT_ENCODE
////////////////////////////////////////////////////////////////////////////////
#endif // CXIMAGE_SUPPORT_MNG