Thread: TGA RLE compressing ( writing ) algorithm on c++

I found this code and I wonder why it does't works ..


// f is an stream

Code:

    void writeTGA(ostream& f, bool rle) const{




    f<<ubyte(0);//ID length
    f<<ubyte(0);//Color map Type


    if(rle)
        f<<ubyte(10);//Image Type Code
    else
        f<<ubyte(2);//Image Type Code


    f<<ubyte(0);//Color map stuff
    f<<ubyte(0);
    f<<ubyte(0);
    f<<ubyte(0);
    f<<ubyte(0);
    f<<ubyte(0);//X Origin of Image
    f<<ubyte(0);//X Origin of Image
    f<<ubyte(0);//Y Origin of Image
    f<<ubyte(0);//Y Origin of Image
    f << ubyte(width%256);
    f << ubyte(width>>8);
    f << ubyte(height%256);
    f << ubyte(height>>8);
    f<<ubyte(24);//Image Pixels Size
    f<<ubyte(32);//Image Descriptor Byte
    if(rle)
    {
        cout<<"rleHeadHead"<<endl;
        ubyte rleHead = 0;
        ubyte diff[128];
        int i = 0;
        while(i<width*height)
            {
                rleHead = 1;
                /* RLE */
                if(i+1 < width*height)
                    while(pixels[i] == pixels[i+1]) {
                        if(i+1 >= width*height || rleHead >= 128)
                            break;


                        rleHead++;
                        i++;
                    }


                if(rleHead > 1)
                {
                    f<< (rleHead+127);
                    f<<pixels[i].b;
                    f<<pixels[i].g;
                    f<<pixels[i].r;
                }


                rleHead = 0;
                /* RAW */
                if(i+1 < width*height)
                {
                    while(pixels[i+rleHead] != pixels[i+rleHead+1])
                    {
                        if( (i+rleHead+1) >= width*height || rleHead >= 128)
                            break;


                        rleHead++;
                    }
                } else
                    rleHead++;


                if(rleHead > 0)
                {
                    f << (rleHead-1);


                    for(int j = 0; j < rleHead; j++)
                    {
                        diff[j] = pixels[i+j].b;
                        diff[j] = pixels[i+j].g;
                        diff[j] = pixels[i+j].r;
                    }
                    f.write((const char*) diff, rle*3);
                    i += rleHead;
                }}}




    else{
            for(int i = 0 ; i < width*height ; i++){
                f<< pixels[i].b;
                f<< pixels[i].g;
                f<< pixels[i].r;}
    }
}

I tried to implement it and it seems not good ..


Otherwise, someone know if it exist a library or just a simple file where I can find this algorithm ?


Thanks you in advance

It's an incomplete section of code to write a TGA image. It's would probably work if you had the rest of the code.