MechBunny Mobile Encoding Question
 

In MechBunny's config file this is the standard pre-set setting:

Setting A

$ffmpeg_mobile_command = "-acodec libfaac -ab 128kb -vcodec mpeg4 -b 800kb -mbd 2 -cmp 2 -subcmp 2"; //settings for ffmpeg mobile version

It encodes very quickly, however the videos don't play on mobile.


Then if you use this setting instead (kb changed to k):

Setting B

$ffmpeg_mobile_command = "-acodec libfaac -ab 128k -vcodec mpeg4 -b 800k -mbd 2 -cmp 2 -subcmp 2"; //settings for ffmpeg mobile version

The videos take maybe 5-10X's as long to convert, but they do play on mobile.


What's the reason for this? And is there something I can do to speed up the process for encoding for mobile.

Setting A will encode 100 videos in 15 mins...with Setting B it may take hours.

Open a Ticket. Why bring it here.

This is an adult webmaster message board, the last time I checked and tickets over the weekend take awhile usually. Make sense?

he has a point - Mech will check their tickets and emails first before checking gfy or other message boards. He will get back to you

The point wasn't for Konrad to see it on here -- you guys hurt my head.

The point was, as hard as it is to obviously understand... I thought there might just be someone else on GFY who knows something about something.

Welcome to gfy

:Graucho

I had Blackmonsters look into this issue and we were able to get the videos to play on mobile without re-encoding, not sure what he did as I am not a programmer. Maybe he will see this or you can ask him.

"-ab" and "-b" is set with "k" not "kb", the first command is just wrong
My best guess is that when you use "kb" the setting is ignored and it keeps the original audio and video bitrate, then if you use "k" it actually changes the bitrate to your setting and this is why it also takes longer, so it's pretty much if you want it to work you have to use "k"

You can use preset to set the speed of encoding, with "-preset fast" it will go faster but the final quality will be worse, "-preset slow" will take more time but will produce better quality even though both files will be the same size. You can try different presets and find one that gives you the best speed to quality ratio that you can tolerate.
Presets you can use:
ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow

However on another note, the whole thing of setting the video rate for mpeg4 is slightly wrong as the format itself is designed for variable bitrate (still moments in video will have low rate while fast motion will have higher rate), if you choose constant the quality of the video will vary based on how fast the motion is and in some very fast phased moments it can be really bad, then on slow phased frames it just waste kbits for nothing; with variable rate it will keep pretty much the same quality regardless of the motion. (imagine in a hardcore scene it shows a close up of the dick hammering the pussy real hard and the quality at that moment gets really bad and grainy...)

I honestly thank you for not being fucking retarded! Thank you.

Thanks blinki bill...and to you too...I honestly thank you for not being fucking retarded as well! Thank you. If I was a normal gfy'er I should probably be cursing at you for trying to help me...but help was what I was looking for, believe it or not on an adult webmaster message board, that may sound silly...but it's true and I appreciate you giving me yours :P

^^you can say thank you without getting all homosexual sounding... just sayin'

My host usually fixes my encoding issues, I give them the encoding log and then they do their magic.

Good post.

:thumbsup

I am also experimenting with this encoding for mobile :

ffmpeg -i $src -vcodec libx264 -s 320x240 -vpre baseline -crf 25 -vpre slower -acodec libfaac -ac 2 -ar 44100 -ab 64k $dest_mobile

I need more feedback from other people before I claim it's the best.
This encoding "should" work on cheaper phones and that might be the trade off in quality.

You are giving two presets "baseline" and "slower" which won't take, one will be ignored, so for max compatibility with mobiles you should probably just use "baseline".
Note that "-vpre" is deprecated, you should use "-preset" to set it instead, also if you don't set "-preset" at all, or use "-vpre" the "-crf" won't take.

I would suggest making some tests like this:
ffmpeg -i $src -vcodec libx264 -s 320x240 -preset baseline -crf 25 -acodec libfaac -ac 2 -ar 44100 -ab 64k $dest_mobile

Me personally - For resolution I allow up to 480p so if the source has lower res I just pass it as it is and if it's higher I scale it down to 480p, for quality I use "-preset slow" and "-crf 23". I don't like to lower the resolution for older mobiles, it really punishes modern devices with displays that will make a laptop look like a "caveman", 480p as a max seems like a good mid point for me. In my testing iphone 4+ works fine with my files, I also tested on 2 old android phones with android 2.1 and 2.3 (one was as bad as single core 600mhz procesor no gpu at all) and it worked there too, so It's fine enough for me

Ok, I'm going to try your changes; sounds pretty good.

Thanks for the suggestions.

:thumbsup

Bump.

What about web videos? Are you guys using your own ffmpeg commands?