自适应 Adapter http live streaming 流媒体实例分析

也可参考这篇博文：http://blog.youkuaiyun.com/jgf_ntu/article/details/8816038

这个链接有自适应码流测试例子：

http://blog.tvruler.com/archive/2012-08-27/adaptive-http-live-streaming-a-simple-test

用vlc测试下面的Adapter http live streaming 码流，是可以支持的。

:http://devimages.apple.com/iphone/samples/bipbop/bipbopall.m3u8

A simple test

This simple test aims at showing how currently available HLS capable devices adapt the video quality to the available network connection quality and throughput. Most logic is performed by the video player software which must:

1. Estimate the available bandwith in real-time
2. Request the video segments of the best playable quality from server
3. Play the segments in a smooth way making them appear as a single stream

We will play a reference video stream on devices connected to the internet using a data-rate-limited wifi-connection. Changing the maximum allowed data-rate during the video playback will allow us to see how fast the device adapts.

You can find the used iPhone reference stream at:http://devimages.apple.com/iphone/samples/bipbop/bipbopall.m3u8 and some more test caseshere or all the related resources at this page.

We will refer to the iPhone samples as they are encoded using a baseline AVC profile that is supported by most mobile devices. Other HLS streams may be encoded with more advanced video profiles that are usaully supported by tablets and set-top-boxes.

The specs of the four streams indexed by the test playlist are:

Stream	Resolution	Bitrate (segment average)
Q1	192x144	210Kbps
Q2	320x240	330Kbps
Q3	480x360	519Kbps
Q4	480x360	753Kbps

m3u8文件：

#EXTM3U
#EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=200000
gear1/prog_index.m3u8
#EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=311111
gear2/prog_index.m3u8
#EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=484444
gear3/prog_index.m3u8
#EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=737777
gear4/prog_index.m3u8