Speed Optimization

By default, top level build scripts (android.sh, ios.sh and tvos.sh) build FFmpeg optimized for size. With the release of v3.0, --speed flag is introduced by build scripts to build FFmpeg optimized for speed.

This flag enables build optimizations that increase the speed of FFmpeg operations. Unfortunately these optimizations also cause library size to increase too much.

The following table shows the effect of enabling --speed flag on Android.

	arm-v7a	arm-v7a-neon	arm64-v8a	x86	x86-64
default library size	10765756	10991128	10959784	12687464	13505440
library size with --speed flag	15185340	15250968	14707528	17726056	18473376
difference	+%41	+%39	+%34	+%40	+%37