# FMLE and AAC codec - why is it needed? **URL:** \ **Category:** Wowza Streaming Engine\ **Created:** [January 6, 2012, 8:05pm UTC](https://community.wowza.com/t/fmle-and-aac-codec-why-is-it-needed/34840 "2012-01-06T20:05:22Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Ben\_Matson](https://avatars.discourse-cdn.com/v4/letter/b/958977/32.png) [@Ben\_Matson](https://community.wowza.com/u/Ben_Matson)\ **Post date:** [January 6, 2012, 8:05pm UTC](https://community.wowza.com/t/fmle-and-aac-codec-why-is-it-needed/34840/1 "2012-01-06T20:05:22Z")
I have a number of webcams streaming h.264 from FMLE via a PC. Although these streams do not have any audio (they’re just webcams), the only way we’ve been able to get them to work via Wowza is to include an 18K audio component (MP3) on top of the 250K video stream. I would now like to push these streams to iPhones, however I have read that the audio codec needs to be AAC. This codec comes by default on a Mac, but not on a PC - it’s a MainConcept plugin at $180 per unit. The problem I have is that with 20 cameras, it’s hardly economical to pay $180 per codec per camera (ie $3,600) for an audio codec that is only required so that the stream will work via Wowza… ie I get absolutely no benefit from the AAC codec! Is there any way around this? ---
**Author:** ![Richard\_Lanham](https://avatars.discourse-cdn.com/v4/letter/r/c68b51/32.png) [@Richard\_Lanham](https://community.wowza.com/u/Richard_Lanham)\ **Post date:** [January 6, 2012, 2:26pm UTC](https://community.wowza.com/t/fmle-and-aac-codec-why-is-it-needed/34840/2 "2012-01-06T14:26:47Z")
MP3 audio is supported in iOS devices. In previous versions of iOS (before version 5) it had to be stereo, 44100Hz and 128kbs to work. iOS 5 supports lower bitrates. I would stick with stereo 44100Hz, and 128kbs. Richard ---
**Author:** ![Richard\_Lanham](https://avatars.discourse-cdn.com/v4/letter/r/c68b51/32.png) [@Richard\_Lanham](https://community.wowza.com/u/Richard_Lanham)\ **Post date:** [January 6, 2012, 8:02pm UTC](https://community.wowza.com/t/fmle-and-aac-codec-why-is-it-needed/34840/3 "2012-01-06T20:02:03Z")
As far as I know, only Smooth streaming to Silverlight has limitation of video only or audio only stream. Video only should work on iOS, Flash, RTSP. And MP3 works on iOS, as I mentioned. Roku is the only Cupertino client that requires AAC that I know of Richard ---
**Author:** ![Richard\_Lanham](https://avatars.discourse-cdn.com/v4/letter/r/c68b51/32.png) [@Richard\_Lanham](https://community.wowza.com/u/Richard_Lanham)\ **Post date:** [January 7, 2012, 1:02pm UTC](https://community.wowza.com/t/fmle-and-aac-codec-why-is-it-needed/34840/4 "2012-01-07T13:02:18Z")
Right, audio is not required. Richard ---
**Author:** ![Ben\_Matson](https://avatars.discourse-cdn.com/v4/letter/b/958977/32.png) [@Ben\_Matson](https://community.wowza.com/u/Ben_Matson)\ **Post date:** [January 7, 2012, 5:03am UTC](https://community.wowza.com/t/fmle-and-aac-codec-why-is-it-needed/34840/5 "2012-01-07T05:03:36Z")
I suppose I should have been more specific - I don’t need any audio at all. My streams are vision-only without any sound. Why does FMLE need to be configured with an audio stream to work via Wowza? And subsequently, why does this audio stream need to be AAC to stream via http to iPhone? ---
**Author:** ![Ben\_Matson](https://avatars.discourse-cdn.com/v4/letter/b/958977/32.png) [@Ben\_Matson](https://community.wowza.com/u/Ben_Matson)\ **Post date:** [January 7, 2012, 2:19pm UTC](https://community.wowza.com/t/fmle-and-aac-codec-why-is-it-needed/34840/6 "2012-01-07T14:19:06Z")
Richard, so you can confirm that Wowza does not require an audio codec to be activated within FMLE to transcode to http properly?