mv_idx = *(ctx->next_cell_data++);
if (mv_idx >= ctx->num_vectors) {
av_log(avctx, AV_LOG_ERROR, "motion vector index out of range\n");
mv_idx = *(ctx->next_cell_data++);
if (mv_idx >= ctx->num_vectors) {
av_log(avctx, AV_LOG_ERROR, "motion vector index out of range\n");