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## Make ffmpeg project steps
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1. Download ffmpeg release source (ffmpeg-4.4.1.tar.gz), download site:http://www.ffmpeg.org/releases/ffmpeg-4.4.1.tar.gz

2. Push ffmpeg tar file(ffmpeg-4.4.1.tar.gz) to ffmpeg directory of project("vendor/open_source/ffmpeg/")

3. Change directory to ffmpeg directory  of project("vendor/open_source/ffmpeg/")

4. Uncompress ffmpeg tar file(ffmpeg-4.4.1.tar.gz) to ffmpeg directory  of project

5. Patch ffmpeg modification(ffmpeg_patch) to ffmpeg release source:
   I.  Copy the file of ffmpeg_patch/* to  overwrite ffmpeg release source file
   II. Makesure the ffmpeg directory of project("vendor/open_source/ffmpeg/") is the root directory of ffmpeg code

Please reference to: project/vendor/open_source/ffmpeg/ffmpeg_patch.sh