How to set different framerates for different streams

Wowza Streaming Engine
1

Hi,

We have 4 or 5 different streams with different bitrates. With the higher bitrate streams we want to send frames with our highest framerate which is set to 25 fps. But on the lower bitrate streams that we use for iphones, Android etc we want to half the framerate speed to 12.5 fps.

  1. Is this possible to do?

  2. Is it possible to configure it in the settings file for example Transrate.xml or is it done by code?

  3. Do you have a specification for xml-tags that can be used in the settings file for the transcoder AddOn?

Thanks Gerard

2

Gerard,

I don’t think this is possible at present with the Wowza Transcoder. You have the Bitrate and FrameSize settings.

Richard

3

Gerard,

FPS setting might be included in a future release of Wowza Transcoder, but I don’t have a time frame. Setting Bitrate is what gets you to low bandwidth clients, and setting frame size appropriately is important for quality at lower bitrates.

Richard

4

Maybe, I’m not sure, but following this method I see these parameters related to FPS.

INFO server comment - # long: vui parameters: timing info use together with time_scale
INFO server comment - mainconcept.num_units_in_tick: 900900
INFO server comment - # long: vui parameters: timing info use together with num_units_in_tick (fps = time_scale/num_units_in_tick)
INFO server comment - mainconcept.time_scale: 27000000
INFO server comment - # long: controls time_scale / num_units_in_tick ration in VUI (field or frame rate)
INFO server comment - mainconcept.frame_based_timing: 0

Richard

5

Is It possible FPS setting on version 3.5?

6

Ok, but would you not expect a transcoder to be able to do such a basic thing like changing the frame rate?

Do other xml-tags exist that are not included in the xml-configuration example files?

If the frame rate cannot be changed, is it something that will be implemented in future releases?

Gerard