《Pro Android Graphics》讀書筆記之第二節Android Digital Video: Formats, Concepts and Optimization

   h.263 支援老顯示器

mpeg4 sp  

supported for commercial video（支援商業視訊）

3gp

google在2.3.3中加入對webm的支援

video stream 4.0以後版本

recommend using mpeg-4 h.264 avc

webm 直播流

mediaplayer：在包android.media中。

videoview：在包android.widget中，direct subclass of the android surfaceview（具體介紹請參考書）。

pixels, resolution, aspect ratios, color depth, alpha channels, pixel blending, image compositing, and even data footprint optimization（類似于圖檔的概念）。

計算影片大小：每幀的大小＊幀率＊時間

  internet 2.0 ip infrastructure is 1536 kbits/second (1.5 mbps, or megabits per second)。

a faster data pipe is at least 2048 kbits/s, or 2 mbits/s or 2 mbps, and video compressed at this higher bit rate exhibits a higher visual quality level. more modern 4g networks claim to be between 3 and 6 mbits/s（3g networks deliver between 600 kbits/s and 1.5 mbits/s, so, on average, these will be 1.5 mbits/s and classified as a medium data pipe）。

dpi：density pixel imagery

for digital video, this also includes different target bit rates, so that you can try to fit all of the different device screen densities and the different processing power capabilities of single-core through quad-core cpu product offerings。

decode  codec

professional solution（專業解決方案（不到1000刀））

editshare lightworks 11（open source）

planetside 

virtualdub video（需要花費大量時間）

從avi到mp4（h264）（文中例子：壓縮比達到120:1）