**6. Ethics**

The authors confirm that all methods were carried out in accordance with relevant guidelines and regulations and were approved by the Lomonosov Moscow State University Bioethics Committee (Protocol #108-0).

## **7. Data Accessibility**

The raw image sequence for the 26 hpf unhatched zebrafish embryo is available from Mendeley Data (http://dx.doi.org/10.17632/kj7mkcw8vn.1).

**Supplementary Materials:** Supplementary video presenting the locally matched images, blood flow images and a resulting vessel image is available from Mendeley Data (http://dx.doi.org/10.17632/kj7mkcw8vn.1).

**Author Contributions:** A.S.M. and A.B.B. conceived and designed the project; M.V.V. and D.D.K. acquired data; A.S.M., M.V.V. and A.V.P. analyzed data; A.S.M. drafted the article; and A.B.B., M.V.V. and D.D.K. revised it critically for important intellectual content. All authors gave final approval of the version to be published and agreed to be accountable for all aspects of the work. All authors have read and agreed to the published version of the manuscript.

**Funding:** This study is supported by the Ministry of Science and Higher Education of the Russian Federation (project 0069-2019-0010). Experiments were performed using the equipment of the Center for Collective Use of the Scientific and Technological Center of Unique Instrumentation of the Russian Academy of Sciences.

**Acknowledgments:** The experiments were carried out on the base of the Center for Collective Use of the Scientific and Technological Center of Unique Instrumentation of the Russian Academy of Sciences.

**Conflicts of Interest:** The authors declare no conflict of interests.
