在心臟發育和心臟相關的病理學領域中，斑馬魚是一種被廣為使用的模式生物，因為其胚胎為透明，並且在幼魚階段時，若是失去循環系統的功能，仍然能夠存活。另外，斑馬魚和哺乳類動物的基因相似度很高，且擁有很高的生育率。這些特徵使得斑馬魚成為強大的哺乳類心臟生理及病理學模式生物。然而，研究人員仍然在尋找一個可以高速評估斑馬魚心臟功能的工具。除了速度以外，經濟效益以及便利性也十分重要。因此，有許多以影像分析技術來取得斑馬魚心臟功能參數的方法被提出。然而，在他們完整的方法中，這些方法仍然需要人工介入，因此仍然有進步的空間。本研究研發出了一個完全自動化的方法來從影片中取得最重要的心臟參數之一──心跳頻率。此方法包含數個可以自動辨識心臟區域進而找到合適的感興趣區域、以及降低影片雜訊的演算法，讓研究人員可以用更有效率的分析斑馬魚的心臟功能。
本研究的結果以現有的三十七部受精後三天（3 dpf）的斑馬魚幼魚心臟區域影片驗證。由本研究的方法取得的心跳頻率和人工計算的心跳頻率有足夠的相似度，且得到的心跳頻率落在人工計算的誤差內，因此可以驗證本研究提出的方法可以準確得由斑馬魚幼魚的心臟區域影片中得到心跳頻率。除此之外，本研究還針對感興趣區域的雜訊濾除效果以及對低頻雜訊濾除演算法的濾波效果進行了分析。

Background: Zebrafish is a widely used model organism for studying heart development and cardiac-related pathogenesis. With the benefits of being able to survive without a functional circulation at larval stages, strong genetic similarity between zebrafish and mammals, prolific reproduction and optically transparent embryos, zebrafish is powerful in modeling mammalian cardiac physiology and pathology as well as in large-scale high throughput screening. An economical and convenient tool for rapid evaluation of fish cardiac function is still in need. There have been several image analysis methods to assess cardiac functions in zebrafish embryos, but they are still improvable to reduce manual intervention in the entire process. This work developed a fully automatic method to retrieve heartbeat rate, an important parameter to analyze cardiac function, from videos. It contains several algorithms to identify the heart region, to reduce video noise and to calculate heartbeat rates.
Results: The proposed method was evaluated with 37 zebrafish embryo videos that were recording at three day post-fertilization. The heartbeat rate measured by the proposed method was similar to that determined by manual counting, indicated that the proposed method can accurately retrieved the heartbeat rate from zebrafish embryo videos.
Conclusion: With the proposed method, researchers do not have to manually select a region of interest while analyzing videos. Moreover, many filters are designed to enhance the heartbeat function in videos, which can alleviate recording defects such as shifting and therefore reduce manual efforts while recording.

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