以FFmpeg解析網路攝影機之H.264視訊串流結構並進行解碼模組之效能評估

Parsing the Structure of H.264 Video Streaming and Evaluating the Performance of Decoding Modules Using FFmpeg

洪瑋澤(Wei-Tse Hung)

指導教授 ： 林啟芳

元智大學/資訊學院/資訊工程學系/碩士(2012年)

https://doi.org/10.6838/YZU.2012.00238

摘要

本論文利用FFmpeg來解析網路攝影機之H.264/AVC視訊串流結構，以檢測不同廠牌的網路攝影機所傳輸的視訊結構內容。我們將FFmpeg解碼過程中所呼叫執行之解碼函式，依H.264/AVC標準解碼器的功能模組進行分類，並記錄所需檢測的項目資訊，詳細的檢視串流結構之完整內容，並量測個別模組所需解碼時間。以所提方法檢視兩款不同廠牌之網路攝影機時，得知其所傳輸的視訊串流結構內容因經濟成本及硬體效能而有所差異，導致支援技術上的程度有限，如所使用的熵解碼方式、DCT反轉換區塊大小、宏塊大小、預測模式的使用選擇不同。在各功能模組所耗費的解碼效能上，經量測得知解碼的效能會因為支援程度及解析度的差異而影響。在非高畫質解析度的情況下，熵解碼與畫面間預測所佔時間最多；當解析度達高畫質時，則去區塊效應濾波器所耗時間上升，與熵解碼及畫面間預測成為三大耗時功能模組。透過以上檢測及時間量測數據之資訊，可利於開發商及研究者進行驗證及確認，使其達到研究前的可行性，及開發後的確認性。

關鍵字

FFmpeg編解碼器 ； H.264串流結構 ； H.264功能模組

並列摘要

In this research, we use the FFmpeg which is a commonly used media player to parse the structure of H.264 Video Streaming. Because of the Network camera manufactured by different chipsets, the structures of video streaming encoded by the chipsets are different. The execution flow of the FFmpeg decoding process is analyzed, and the corresponding information of detection is recorded. We examine the complete content of video streaming, and measure the decoding time for each function module. Two different network cameras are prepared and tested by the proposed method, and the results are tabulated for the convenience of comparison. The performance of various functional models of H.264 are also analyzed, and the results are represented by charts.

並列關鍵字

FFmpeg Codec ； H.264 Streaming Structure ； H.264 Functional Modules

參考文獻

A. Luthra, G.J. Sullivan, and T. Wiegand, “Introduction to the special issue on the H.264/AVC video coding standard,” IEEE Transactions on Circuits and Systems for video Technology, vol. 13, pp. 557-559, July 2003.

A. Tamhankar, and K.R. Rao, “An overview of H.264/MPEG-4 part 10,” in Proceedings of 4th EURASIP Conference focused on Video/Image Processing and Multimedia Communications, 2003, vol. 1, pp. 1-51.

G.J. Sullivan, P.N. Topiwala, and A. Luthra, “The H.264/AVC advanced video coding standard: overview and introduction to the fidelity range extensions,” in Proceedings of SPIE conference on Applications of Digital Image Processing XXVII, 2004, vol. 5558, pp. 454-474.

D. Marpe, T. Wiegand, and S. Gordon, “H.264/MPEG4-AVC fidelity range extensions: tools, profiles, performance, and application areas,” in Proceedings of IEEE International Conference on Image Processing, 2005, vol. 1, pp. I-593-6.

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