Category

Development Platform
Home > SourceCode/Document > Multimedia program > DVD > View Code
ditherer.cc
Package: dvd-munitions.tar.gz　[view]
Upload User: aoeyumen
Upload Date: 2007-01-06
Package Size: 3329k
Code Size: 5k
Category:

DVD

Development Platform:

Unix_Linux

ditherer.cc：Code Content
  1. #include <iostream>
  2. #include "ditherer.hh"
  4. map<string,Ditherer * (*)()> Ditherer::ditherStore;
  6. int Ditherer::addModule(class Ditherer * (*alloc)(),string name) {
  7.    Ditherer::ditherStore[name]=alloc;
  8. }
  10. Ditherer * Ditherer::allocModule(string name) {
  11.    map<string,Ditherer * (*)()>::iterator store_it;
  13.    if (ditherStore.empty()) {
  14.       Ditherer::loadDefaultModules();
  15.    }
  16.    store_it=ditherStore.find(name);
  17.    if (store_it != ditherStore.end()) {
  18.       return ((store_it->second))();
  19.    } else {
  20.       return 0;
  21.    }
  22. }
  24. string Ditherer::getRegisteredModules() {
  25.    if (ditherStore.empty()) {
  26.       Ditherer::loadDefaultModules();
  27.    }
  28.    
  29. }
  31. void Ditherer::setBpp(int bpp) {
  32.    if (!_bpp) {
  33.       _bpp=bpp;
  34.       if (!_pixelSize) {_pixelSize=bpp/8+((bpp%8 != 0)?1:0);}
  35.    } else {
  36.       if (bpp!=_bpp) {
  37.          cerr<<"Ditherer::setBpp() can't be called if _bpp is already set"
  38.              << endl;
  39.          exit(1);
  40.       }
  41.    }
  42. }
  44. void Ditherer::setPixelSize(int pixelSize) {
  45.    if (_pixelSize == 0 || pixelSize == _pixelSize) {
  46.       _pixelSize=pixelSize;
  47.    } else {
  48.       cerr<<"Ditherer::setPixelSize() can't be called if _pixelSize is already set"
  49.           << endl;
  50.       exit(1);
  51.    }
  52. }
  54. GenericDitherer::GenericDitherer() {
  55.    tempory_Y=(unsigned char*)0;
  56.    tempory_Cr=(unsigned char*)0;
  57.    tempory_Cb=(unsigned char*)0;
  58. }
  60. GenericDitherer::~GenericDitherer() {
  61.    delete tempory_Y;
  62.    delete tempory_Cr;
  63.    delete tempory_Cb;
  64. }
  66. void GenericDitherer::resizeYandDither(unsigned char * tY,
  67.                                        unsigned char * tCr,
  68.                                        unsigned char * tCb,
  69.                                        unsigned char * dithered_img,
  70.                                        int origXsize,int origYsize,
  71.                                        int newYsize,int screenWidth) {
  72.    int nb_skip=origYsize-newYsize+1;
  73.    int skipped;
  74.    int block_height;
  75.    
  76.    for (skipped=0;skipped<nb_skip;++skipped) {
  77.       block_height=(skipped+1)*origYsize/nb_skip-(skipped)*origYsize/nb_skip;
  78.       ditherBlock(tY,tCr,tCb,
  79.                   dithered_img,
  80.                   origXsize,block_height-1,screenWidth);
  81.       tY+=block_height*origXsize;
  82.       tCr+=block_height/2*origXsize/2;
  83.       tCb+=block_height/2*origXsize/2;
  84.       dithered_img+=(block_height-1)*origXsize*_pixelSize;
  85.    }
  86. }
  88. void GenericDitherer::changeSize(unsigned char * orig,unsigned char * dst,
  89.                                  int origXsize,int origYsize,
  90.                                  int newXsize, int newYsize) {
  91.    int k,l=0;
  92.    int ll;
  93.    
  94.    for(l=0;l<newYsize;l++) {
  95.       ll=(l*origYsize/newYsize)*origXsize;
  96.       if (origXsize==newXsize) {
  97.          /* just a vertical aspect ratio change) */
  98.          memcpy(dst,orig+ll,origXsize);
  99.          dst+=origXsize;
  100.       } else {
  101.          for(k=0;k<newXsize;++k) {
  102.             *(dst++)=orig[ll+(k*origXsize/newXsize)];
  103.          }
  104.       }
  105.    }
  106. }
  108. void  GenericDitherer::checking() {
  109.    if (_pixelSize==0) {
  110.       cerr<<"method GenericDitherer::setBpp() or GenericDitherer:setPixelSize() must be called before dithering"
  111.           <<endl;
  112.       exit(1);
  113.    }
  114. }
  116. void GenericDitherer::dither(unsigned char * tY,
  117.                              unsigned char * tCr,
  118.                              unsigned char * tCb,
  119.                              unsigned char * dithered_img,
  120.                              int imgWidth,
  121.                              int imgHeight,
  122.                              int viewWidth,
  123.                              int viewHeight,
  124.                              int screenWidth) {
  125.    checking();
  127.    if (tempory_Y==0) {
  128.       tempory_Y=new unsigned char[viewWidth*viewWidth];
  129.       tempory_Cr=new unsigned char[viewWidth/2*viewWidth/2];
  130.       tempory_Cb=new unsigned char[viewWidth/2*viewWidth/2];
  131.    }
  132.    
  133.    if (imgWidth!=viewWidth
  134.        || imgHeight!= viewHeight) {
  135.       if ((imgWidth==viewWidth)
  136.           && (imgHeight>viewHeight)
  137.           && (viewHeight>(imgHeight/2))) {
  138.          resizeYandDither(tY,tCr,tCb,
  139.                           dithered_img,
  140.                           imgWidth,imgHeight,viewHeight,screenWidth);
  141.       } else {
  142.          /* full resize needed */
  143.          changeSize(tY,tempory_Y,imgWidth,imgHeight,viewWidth,viewHeight);
  144.          changeSize(tCr,tempory_Cr,imgWidth/2,imgHeight/2,viewWidth/2,viewHeight/2);
  145.          changeSize(tCb,tempory_Cb,imgWidth/2,imgHeight/2,viewWidth/2,viewHeight/2);
  146.          ditherBlock(tempory_Y,tempory_Cr,tempory_Cb,
  147.                      dithered_img,
  148.                      viewWidth,viewHeight,screenWidth);
  149.       }
  150.    } else {
  151.       ditherBlock(tY,tCr,tCb,
  152.                   dithered_img,
  153.                   viewWidth,viewHeight,screenWidth);
  154.    }
  155. }