c pvr转存pvr.ccz格式

pvr.ccz 是把pvr用zlib算法压缩后的图像格式，其优点是可以提升文件读取效率。 

大多数情况下我们可以用一些工具来将pvr压缩到pvr.ccz ,下面提供一个c++方法来完成这个过程

int CompressPvrToCCZFile(unsigned char *buffer,unsigned int fileLength, const char *newFilePath)

{
　　//buffer pvr文件二进制数据，fileLength 文件长度，newFilePath 保存地址

    unsigned long bufferSize = fileLength;

    char* DestBuffer=new char[(uInt)bufferSize];memset(DestBuffer, 0, bufferSize);

    errno_t err; //错误变量的定义

    err = compress((Bytef*)DestBuffer,(uLongf*)&bufferSize,(const Bytef*)buffer,(uLongf)fileLength);



    //

    CCZHeader header;

    header.version = 256;

    header.len = ((fileLength & 0x000000ff) >> 24 | (fileLength & 0x0000ff00) >> 8 | (fileLength & 0x00ff0000) << 8 | (fileLength & 0xff000000) << 24);

    header.compression_type = CCZ_COMPRESSION_ZLIB;

    

    header.sig[0] = 'C';

    header.sig[1] = 'C';

    header.sig[2] = 'Z';

    header.sig[3] = '!';



    //保存文件

    FILE *fp = fopen(newFilePath, "wb+");

    if (!fp)

    {

        delete []DestBuffer;



        return -1;

    }

    fwrite(&header, sizeof(header), 1, fp);

    fwrite(DestBuffer, bufferSize, 1, fp);

    fclose(fp);

    delete []DestBuffer;



    return 1;

}