@SGaist
Hi SGaist,
i solved manupulating my BA manually
int bW = bitmap.value("width").toInt();
int bH = bitmap.value("height").toInt();
QString shortFileName = bitmap.value("id").toString();
QString fileName = btb::ResourceManager().getClipDir().absolutePath().append("/"+shortFileName+".png");
QByteArray ba = bitmap.value("rect").toByteArray();
QByteArray to = QByteArray();
for(int i=0; i<bWbH;i++)
{
// ARGB -> ABGR
to.append( ba[i4+3]);
to.append( ba[i4+2]);
to.append( ba[i4+1]);
to.append( ba[i4]);
}
QImage image((const unsigned char)to.data(),bW,bH,QImage::Format_RGB32);
//image.invertPixels();
image.save(fileName,"PNG");

thanks for help!