auto codecCtx = avcodec_alloc_context3(codec);
        int err;

        codecCtx -> width = size.width();
        codecCtx -> height = size.height();
        codecCtx -> pix_fmt = format == JPEG ? AV_PIX_FMT_YUVJ420P : AV_PIX_FMT_RGBA;
        codecCtx -> time_base.num = 1;
        codecCtx -> time_base.den = 25;

        if ((err = avcodec_open2(codecCtx, codec, NULL)) == 0) {  // Crashes here
        }