MP4 H264 Transcoding

Dear All,
I have my 100 video files which i need my friends to be able to view on different devices
windows, MAC, iPhone, and android.
All My 100 Videos are MP4 (H264)
I have installed Windows Subsonic 6, and have added my 100 videos, Now when i play video in Google Chrome(in windows) by going to Index, i can see video playing very well. but same video is not working in Firefox.
I have no idea about "Transcoding" and ffmpeg (i Just learned many thing from this forum that i need to Transcode videos)
I have tried to put a Transcoding command as follows
Name = MP4_CODE
Convert from = avi mpg mpeg mp4 mkv mov wmv ogv divx m2ts
Convert to = flv
Step 1= ffmpeg -ss %o -i %s -async 1 -b %bk -s %wx%h -ar 44100 -ac 2 -v 0 -f flv -vcodec libx264 -strict experimental -preset superfast -threads 4 -v 0 -
and it is not working.( i am still able to video video is chrome in windows, but not loading in windows firefox)
and in addition i have no idea how will i manage to view on mobile devices
Additional Information:
1) mp4 is already added in Steetings --> General --> Video files
2) "MP4_CODE" Transcoding is enabled in Steetings -->Player--> Player 1 and player 2
3) Observed that as soon as start playing video in FireFox my computer DU meter displays that system is downloading
4) Further Observed that in C:\subsonic\subsonic.log, nothing happens when i play video, that is no information about Transcoding
Any help in achiving my task to video my mp4(h264) videos in multiple platforms.
Thank You.
I have my 100 video files which i need my friends to be able to view on different devices
windows, MAC, iPhone, and android.
All My 100 Videos are MP4 (H264)
I have installed Windows Subsonic 6, and have added my 100 videos, Now when i play video in Google Chrome(in windows) by going to Index, i can see video playing very well. but same video is not working in Firefox.
I have no idea about "Transcoding" and ffmpeg (i Just learned many thing from this forum that i need to Transcode videos)
I have tried to put a Transcoding command as follows
Name = MP4_CODE
Convert from = avi mpg mpeg mp4 mkv mov wmv ogv divx m2ts
Convert to = flv
Step 1= ffmpeg -ss %o -i %s -async 1 -b %bk -s %wx%h -ar 44100 -ac 2 -v 0 -f flv -vcodec libx264 -strict experimental -preset superfast -threads 4 -v 0 -
and it is not working.( i am still able to video video is chrome in windows, but not loading in windows firefox)
and in addition i have no idea how will i manage to view on mobile devices
Additional Information:
1) mp4 is already added in Steetings --> General --> Video files
2) "MP4_CODE" Transcoding is enabled in Steetings -->Player--> Player 1 and player 2
3) Observed that as soon as start playing video in FireFox my computer DU meter displays that system is downloading
4) Further Observed that in C:\subsonic\subsonic.log, nothing happens when i play video, that is no information about Transcoding
Any help in achiving my task to video my mp4(h264) videos in multiple platforms.
Thank You.