Using Elastic Transcoder to setup Adaptive Streaming files for VOD

Wowza Streaming Engine
1

Hello,

I’m trying to setup and use Wowza Streaming Engine on EC2 instance.

First of all I setted up by Marketplace a preconfigured Wowza EC2 instance and all is going well.

Now I’m following the instruction to setup ABR (adaptive streaming) starting from my original 1920x1080 mp4 file.

So I planned to use Elastic Transcoder service to transcode my file to different bitrates.

From Wowza documentation I read "Adaptive bitrate (ABR) streaming of video on demand (VOD) content to Adobe Flash Player, Apple iOS devices, MPEG-DASH players, and Microsoft Silverlight requires that you have multiple files that are pre-encoded to the desired bitrates for streaming. For stream-switching to occur properly, the keyframes of each of the files must be aligned with each other. This must be done at encoding time and can be achieved by setting the keyframe interval and frame rate values to be the same for each encoded file… "

So looking at Elastic Transcoder Presets, I planned to test these presets

System preset: Generic 1080p

System preset: Generic 720p

System preset: Generic 480p 16:9

System preset: Generic 360p 16:9

but I’m not sure if I have to modify the following parameters and with which values:

  • Fixed Number of Frames Between Keyframes to TRUE

  • Frame Rate (seems to be actually the same for all the choosen presets)

Kind regards,

Matt

2

Hi Matt,

Based on the information you provided from the Elastic Transcoder Preset, you should keep the “Fixed Number of Frames Between Keyframes” set to TRUE.

The framerate should be the same for all resulting files that your Transcoder creates.

You can do a test encoding run and see how the output files work with a SMIL file in.

Regards,

Alex