2个问题:
1- 我试图理解Rate Based Adaptation Logic 代码(完整的 cpp 代码在底部),我不太明白什么是 getBufferedPercent
函数返回。
2- 有什么地方可以找到有关此类功能的正确文档吗?
这是 RateBasedAdaptationLogic.cpp 代码:
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "RateBasedAdaptationLogic.h"
using namespace dash::logic;
using namespace dash::xml;
using namespace dash::http;
using namespace dash::mpd;
RateBasedAdaptationLogic::RateBasedAdaptationLogic (IMPDManager *mpdManager, stream_t *stream) :
AbstractAdaptationLogic (mpdManager, stream),
mpdManager (mpdManager),
count (0),
currentPeriod (mpdManager->getFirstPeriod()),
width (0),
height (0)
{
this->width = var_InheritInteger(stream, "dash-prefwidth");
this->height = var_InheritInteger(stream, "dash-prefheight");
}
Chunk* RateBasedAdaptationLogic::getNextChunk()
{
if(this->mpdManager == NULL)
return NULL;
if(this->currentPeriod == NULL)
return NULL;
uint64_t bitrate = this->getBpsAvg();
if(this->getBufferPercent() < MINBUFFER)
bitrate = 0;
Representation *rep = this->mpdManager->getRepresentation(this->currentPeriod, bitrate, this->width, this->height);
if ( rep == NULL )
return NULL;
std::vector<Segment *> segments = this->mpdManager->getSegments(rep);
if ( this->count == segments.size() )
{
this->currentPeriod = this->mpdManager->getNextPeriod(this->currentPeriod);
this->count = 0;
return this->getNextChunk();
}
if ( segments.size() > this->count )
{
Segment *seg = segments.at( this->count );
Chunk *chunk = seg->toChunk();
//In case of UrlTemplate, we must stay on the same segment.
if ( seg->isSingleShot() == true )
this->count++;
seg->done();
chunk->setCalculatedBW(this->getBpsAvg());
return chunk;
}
return NULL;
}
const Representation *RateBasedAdaptationLogic::getCurrentRepresentation() const
{
return this->mpdManager->getRepresentation( this->currentPeriod, this->getBpsAvg() );
}
最佳答案
您的问题是关于 videolan 项目的代码。您粘贴的代码是 on the videolan web server .
The videolan developers page说他们有一个 IRC channel (irc://irc.videolan.org/videolan) 和 mailing lists您可以在哪里提问。
我建议您多阅读 DASH stream_filter module 中的代码,尤其是缓冲区目录(它计算您所询问的缓冲百分比),然后在 IRC 或邮件列表上询问具体问题。
不幸的是,这段代码似乎没有注释或文档。如果正常 channel 没有帮助,您可以询问作者。他们很友好地在文件顶部的版权声明中包含了电子邮件地址。
关于c++ - bufferedPercent 是如何工作的,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/20184926/