How to batch convert FLV files to MP4?

November 17, 2014 1:16 PM

I've got numerous video files on a network drive in FLV format that I would like to change to MP4, hopefully with free software.

I've got a video share on our home NAS drive that is a mixture FLVs (mostly downloaded from the web) and MP4s (mostly ripped DVDs via handbrake). On my android phone I use ES file explorer's built-in player to watch movies but it wont play FLVs so I want to change everything over to MP4.

This question is really about that conversion but I'm not dead-set against a new player suggestions. I have VLC for Android but I hate it for it's interface and awful performance on my LAN (it does play FLVs, albeit awkwardly). It seems like it is most people's go-to but I don't want to use it unless I have to.

Thanks!

posted by werkzeuger to Computers & Internet (10 answers total)

Response by poster: Sorry, I should add we're running windows 7 and 8 and android smartphones.
posted by werkzeuger at 1:21 PM on November 17, 2014

Best answer: I'd use ffmpeg. There are versions for windows and linux and it can also be installed on OSX. Since it's a command line utility, batch conversion is easy. The command line interface can be a little tricky to master but there are numerous "how-tos" that cover using it. Here's one specifically discussing converting flv to mp4 - http://www.wikihow.com/Convert-a-Flash-Video-File-(.flv)-to-MP4-with-FFMpeg. There are also GUIs that sit on top of it that are capable of converting more than one file at a time. My favorite is handbrake. Here's the link to handbrake https://handbrake.fr/ and here's a video talking about how to use handbrake to convert flv to mp4 - https://www.youtube.com/watch?v=FkMsGxM2ZDg
posted by grimtheelder at 1:25 PM on November 17, 2014 [2 favorites]

My go-to here for converting would be Adobe Media Encoder. You should be able to use the free trial for a one off project.
posted by Nonsteroidal Anti-Inflammatory Drug at 1:25 PM on November 17, 2014 [1 favorite]

Otherwise you should look into ffmpeg.
posted by Nonsteroidal Anti-Inflammatory Drug at 1:26 PM on November 17, 2014

Best answer: On the player front, MX player (usually looks nicest, interface is snappy), Dice Player (plays .flv's better than mx player), and BS player (best battery) are my video players. I use them directly via ES file manager. All of my videos are on my lan, sadly exported via samba was the easiest method to get access on my android phone.
posted by nobeagle at 1:27 PM on November 17, 2014

I've been using aTube Catcher for a variety of tasks. First, it does a great job of downloading streaming video, as it should. But it also has a media conversion tab which, if I recall correctly, has batch conversion ability with file naming convention.

Ah. Yes, it does indeed allow batch conversion:
"Do you have FLV files on your disk (downloaded with other tools for example) or videos in other formats waiting to be converted to 3GP,3G2,MPEG1,2,3,4,DVD,VCD,IPOD,WMV,XVID,AVI,etc?, and you hate to convert one by one?... copy the paths to a simple text file and open it with aTC, it will process and recode all that files."
posted by malthusan at 1:32 PM on November 17, 2014

Response by poster: These are all very helpful. I wasn't aware Handbrake would do conversion or work with sources other than optical media.

Thank you guys! Other suggestions are very welcome too.
posted by werkzeuger at 2:12 PM on November 17, 2014

Best answer: I also use Handbrake. I'm on a Mac and I had extremely large FLV files. VLC converted them, but decoded the audio incorrectly. Quicktime wouldn't convert it successfully at all (even with the Perian add on). In the end, I had to use Handbrake and it worked wonderfully.
posted by ethidda at 2:46 PM on November 17, 2014 [1 favorite]

There is also handbrakebatch to avoid the tedium of adding files one at a time to Handbrake. I don't know if there is a Windows version of it.
posted by ridogi at 7:25 PM on November 17, 2014

Handbrake is way easier to use, but the default doesn't do batch conversion of many files. ffmpeg will do batch easy but you have to be comfortable with command line hacking and, specifically, ffmpeg's arcane syntax. (See also avconv, the fork of ffmpeg that Ubuntu favors.)

Either way, the key thing is to pick a format that your playback device is happy with and convert solely to that. You said MP4, but that's just the container format. You also have to pick codecs. MP4 with H.264 video and AAC audio is a good reliable format. Handbrake calls that the "iPad profile". That's stereo sound; it's harder if you want surround.
posted by Nelson at 8:43 PM on November 17, 2014