一個快速與高品質轉換JPEG靜態影像為H.264串流格式之方法

A Fast and High Quality Method for JPEG to H.264 Transcoding

李相賢(Siang-Sian Lee)

指導教授 ： 林啟芳

元智大學/資訊學院/資訊工程學系/碩士(2009年)

摘要

進入21世紀後，多媒體影像傳播變的更普遍，各種視訊影像規格提供多元的應用服務空間，其中H.264的壓縮技術具有高壓縮率和極佳的壓縮品質，大幅度降低數位影像資料儲存量，及減少資料傳輸的負擔，幾乎是串流格式的代表。另一方面，JPEG是靜態影像壓縮最被廣泛使用的格式，發展很早所以技術成熟穩定且影像品質極佳，對後續發展智慧視訊辨識系統較具優勢。考量在未來應用上，有愈來愈多支援H.264格式的產品出現，舉凡3G手機及個人掌上型電腦等，為了使JPEG靜態影像也能在這些產品上流暢播出，本論文提出方法，將JPEG影像格式轉變為H.264的標準串流格式，除能保留原來JPEG的高品質影像外，並且具備低複雜度與快速轉換的特性。
我們提出修正開放式架構的方法，並對過程中所遭遇問題提出解決辦法，包括畫面模式的選擇、宏塊模式與區塊模式的選擇、整數轉換的問題、色彩模式的轉換、量化選擇、及預測值問題。除此之外，我們也討論可能導致轉換失真的原因。最後，實驗結果將驗證所提方法的優越性。

關鍵字

JPEG ； H.264 ； 格式轉換 ； 開放式架構

並列摘要

In the 21st century, multimedia files are increasingly common as we use different compression specifications in different services. A newly format named H.264 compression technology reduces data storage and information transmission efficiently by offering excellent compression ratio and video quality for movies. JPEG compression technology, on the other hand, has been used to store picture files for many years. Thus, it is necessary to propose a method to convert JPEG format to H.264 format.
In this paper, we proposed a method for converting images from JPEG format to H.264 format. The proposed method of format conversion is characterized by good quality and simple flowchart. We modified the open-loop architecture and set up the parameters when we transcoded. As a consequence, the superiority of the proposed method will be shown in the experimental result.

並列關鍵字

JPEG ； H.264 ； Transcoding ； Open-Loop Architecture

參考文獻

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