H.264因為擁有超低資料傳輸率，很適合應用於遠端傳輸，我們希望能夠架設一個當我們出差到國外時，也可以看到家鄉各種節目的平台，但最常發生的問題就是網路頻寬不足或是受到干擾的現象，所以我們提出了一種Auto bit-rate的方法，來降低當頻寬不足或是網路不穩定時，仍舊能夠收看穩定得影音品質，雖然要犧牲掉解析度，但穩定的影音品質會比失真率來的更好，我們之所以提出此種架構是因為，便利那些不懂得調整影音畫質的人，讓系統可以自動的調整最穩定的品質和當時網路可以傳輸的最高解析度。為了驗證Auto bit-rate可行性,所以使用的測試平台為嵌入式平台，本文使用平台MCU為STR9105內建MAC及USB，執行速率方面約為200MHz，另外加H.264媒體處理晶片Ｍobilygen MG1264，是一個適合用在H2.64編碼與解碼的IC，由MG1264將影音訊號編碼成H2.64再由MCU透過MAC傳出網路封包，另外架設一台PC來做接收播放來做確認影像是否有即時與影像是否有延遲。模擬各種實際網路可能發生的因素，該如何去設置bit-rate的大小，不但可以讓H.264播放的更順暢，也可以進一部的達到管理順暢度與解析度的目的。 Because the characters of H.264 technique form as low ratio data-rate transmitted, it is very suitable to apply the remote transmission. Hopefully, we wish to be able to wath all domestic TV-programs by installing some platform when being far away outdoor even oversea. It always happens to lack enough bandwidth or get worst signal, thus the Auto bit-rate technique improves the above two points; Although it may loss fine dpi, the stable AV quality is still worth overall. That is why we promote the Auto bit-rate technique with more convenience for tuning the optimal configuration in system. For testing and verifying the capacity of the Auto bit-rate tech., we take STR9105 with MAC and USB (200MHz) as MCU; furthermore, a Mobilygen MG1264, well adapts to encode and decode the H.264 format. The process is that AV data is encoded by MG1264 as H.264 format, then form as network packets by MAC streaming. In advance, it is necessary to reconfirm the quality during inputting and outputting packet by normal PC at time. We also realize how to configure the size of the bit-rate; not only for making the H.264 format more smoother, but for realizing the capacity of unhindered and the optimal management in advance.
關聯:
2007 NCS 中華民國九十六年全國計算機會議大會論文集=Proceedings of 2007 National Computer Symposium，6頁
