字幕解碼庫概要設(shè)計報告

（decoder如圖2所示。其中:2.字幕碼流解碼出來，進(jìn)而將解碼出來的字幕交給subDispManager進(jìn)行管理。Decoder字幕解碼器internaldecoder，idxsub字幕解碼器。流進(jìn)行解碼，將解碼出來的字幕存放到subDispManager模塊進(jìn)行管理。Idxsub是一種比較特殊的字幕，嚴(yán)格上說它是一種外掛字幕，但與普通的外掛字幕不4.了兩個變量validSubNum（有效的字幕數(shù)目）nEmptySubNum（空閑的字幕buffer數(shù)目）來控制著6buffer，解碼器每解碼出來一條字幕時，validSubNum1，nEmptySubNum1request一條字幕時，validSubNum1request到的字幕flush到字幕庫時，nEmptySubNum加1.12探測字幕文件的基本信息(輸入為文件句柄3456789如果外掛字幕，應(yīng)用程序首先調(diào)用ProbeSubtitleStreamProbeSubtitleStreamFdFlushSubtitleItem將圖像Buffer歸還解碼器。不斷地調(diào)用RequestSubtitleItem函數(shù)獲取字幕，并將顯示完的字幕通過調(diào)用FlushSubtitleItem函數(shù)還回給字幕庫。下文詳細(xì)介紹各個APIintProbeSubtitleStream(constchar*int*pStreamCount)strFilePath：字幕文件的路徑，成功：0失?。?1intProbeSubtitleStreamFd(intintoffset,intlen,SubtitleStreamInfo**int*Fd:字幕文件句柄len：有效數(shù)據(jù)的長度0失?。?1SubtitleDecoder*成功則返回解碼器指針SubtitleDecoder*；失敗則返回NULL失敗則返回NULL； voidResetSubtitleDecoder(SubtitleDecoder*p,int64_t通過無intDecodeSubtitleStream(SubtitleDecoder*SubtitleStreamDataInfo*通過 2 1 0：解碼ok 1SDECODE_RESULT_NO_FRAME_BUFFER4：無FRAMEBUFFER對于內(nèi)嵌字幕，因?yàn)樽帜淮a流是從parserSubtitleItem*NextSubtitleItem(SubtitleDecoder*通過該字幕在字幕顯示隊(duì)列即FRAMEBUFFERSubtitleItem*RequestSubtitleItem(SubtitleDecoder*通過無voidFlushSubtitleItem(SubtitleDecoder*p,SubtitleItem*通過無無unsigned外掛字幕的文件內(nèi)容的offset5.2字幕顯示的unsignedunsignedbufferbuffert當(dāng)前這一筆字幕碼流的當(dāng)前這一筆字幕碼流的當(dāng)前這一筆字幕碼流的UnsignedUnsignedUnsignedUnsigned空閑的bufferUnsigned當(dāng)前字幕的當(dāng)前字幕的中間subdispbufdvdsubDivxA或DivxB針外掛字幕："sub","srt","smi", "txt","ssa","aqt","jss","ass","vsf","tts","stl","zeg","ovr","dks","lrc","sbt","vkt","pjs","mpl","scr","psb","asc","s2k","sst","son","ssts",內(nèi)嵌字幕：ThisdocumentistheoriginalworkandcopyrightedpropertyofAllwinnerTechnology(“Allwinner”).ReproductioninwholeorinpartmustobtainthewrittenapprovalofAllwinnerandgiveclearacknowledgementtothecopyrightowner.TheinformationfurnishedbyAllwinnerisbelievedtobeaccurateandreliable.Allwinnerreservestherighttomakechangesincircuitdesignand/orspecificationsatanytimewithoutnotice.Allwinnerdoesnotassumeanyresponsibilityandliabilityforitsuse.Norforanyinfringementsofpatentsorotherrightsofthethirdpartieswhichmayresultfromitsuse.NolicenseisgrantedbyimplicationorotherwiseunderanypatentorpatentrightsofAllwinner.Thisdatasheetneitherstatesnorimplieswarrantyofanykind,includingfitnessforanyparticularapplication.7.ThisdocumentistheoriginalworkandcopyrightedpropertyofAllwinnerTechnology(“Allwinner”).ReproductioninwholeorinpartmustobtainthewrittenapprovalofAllwinnerandgiveclearacknowledgementtothecopyrightowner.TheinformationfurnishedbyAllwinnerisbelievedtobeaccurateandreliable.Allwinnerreservestherighttomakechangesincircuitdesignand/orspecificationsatanytimewithoutnotice.Allwinnerdoesnotassumeanyresponsibilityandliabilityforitsuse.Norforanyinfringementsofpatentsorotherrightsofthethirdpartieswhichmayresultfromitsuse.Nolicenseisgrantedbyimplicationorothe