gdigrab->header_size = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +
(bpp <= 8 ? (1 << bpp) : 0) * sizeof(RGBQUAD) /* palette size */;
gdigrab->time_base = av_inv_q(gdigrab->framerate);
gdigrab->header_size = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +
(bpp <= 8 ? (1 << bpp) : 0) * sizeof(RGBQUAD) /* palette size */;
gdigrab->time_base = av_inv_q(gdigrab->framerate);