## 5 Conclusions  
We designed YeastNet to improve the accuracy of identifying individual _S. cerevisiae_ cells from bright-field microscopy images. Our model is based on the U-Net semantic segmentation architecture and it was trained using a manually labeled dataset. YeastNet segments bright-field images by generating pixel-wise predictions between background and cell classes. We compared YeastNet to a classic method and the current state-of-the-art tool for general _S. cerevisiae_ segmentation and tracking. We achieve higher performance in every metric used: intersection over union, segmentation accuracy, and tracking accuracy. We also present a new dataset, consisting of 150 bright-field microscopy images of budding yeast. This dataset consists of 50 fields of view of a growing colony, taken at 3 levels of focus, as well as, manually segmented ground-truth segmentation masks. Thispublicly available dataset for bright-field microscopy segmentation of yeast adds to the limited public data, and we hope it is used to advance research in this domain. Conceptualization, D.S. and M.K. ; methodology, D.S., Y.L. and P.X. ; software, D.S. ; validation, D.S. ; formal analysis, D.S. ; investigation, D.S. ; resources, M.K. and M.C.-C.; data curation, D.S. and H.P. ; writing--original draft preparation, D.S. ; writing--review and editing, D.S., Y.L., P.X., H.P., M.K., M.C.-C.; visualization, D.S. ; supervision, M.K. and Y.L. ; project administration, M.K. and M.C.-C.; funding acquisition, M.C.-C. and M.K. All authors have read and agreed to the published version of the manuscript. Not applicable. The datasets and code used during the current study are available at [[https://github.com/kaernlab/YeastNet](https://github.com/kaernlab/YeastNet)]([https://github.com/kaernlab/YeastNet](https://github.com/kaernlab/YeastNet)), accessed: 8 December 2019. Two publicly available datasets were used from the Yeast Image Toolkit (Dataset 1 and Dataset 3). The Yeast Image Toolkit is available at: ([[http://yeast-image-toolkit.biosim.eu/pmwiki.php](http://yeast-image-toolkit.biosim.eu/pmwiki.php)]([http://yeast-image-toolkit.biosim.eu/pmwiki.php](http://yeast-image-toolkit.biosim.eu/pmwiki.php)), accessed: 8 December 2019). The authors declare no conflict of interest. The following abbreviations are used in this manuscript: \begin{tabular}{l l} IoU & Intersection over Union \\ CNN & Convolutional Neural Net \\ \end{tabular}   
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