int32_t display_matrix[9];

if (ctx->sensor_orientation) {
    av_display_rotation_set(display_matrix, 360 - ctx->sensor_orientation);
}

if (ctx->lens_facing == ACAMERA_LENS_FACING_FRONT) {
    av_display_matrix_flip(display_matrix, 1, 0);
}

uint8_t *side_data = av_packet_new_side_data(&pktl_next->pkt, AV_PKT_DATA_DISPLAYMATRIX, sizeof(display_matrix));
memcpy(side_data, display_matrix, sizeof(display_matrix));