int avpicture_get_size(enum PixelFormat pix_fmt, int width, int height) { AVPicture dummy_pict; if(av_image_check_size(width, height, 0, NULL)) return -1; switch (pix_fmt) { case PIX_FMT_RGB8: case PIX_FMT_BGR8: case PIX_FMT_RGB4_BYTE: case PIX_FMT_BGR4_BYTE: case PIX_FMT_GRAY8: // do not include palette for these pseudo-paletted formats return width * height; } return avpicture_fill(&dummy_pict, NULL, pix_fmt, width, height); }