All StreamZilla CDN accounts offer integrated, high performance support for all popular delivery protocols, formats and players.

Do you have generic transcoding/encoding tips?

Flash live streaming settings

We strongly advise using the following encoding settings. If you use other settings, we cannot guarantee the stability, reliability or availability of your streams:

- video codec: H.264 (not VP6!)
- audio codec: AAC (not MP3!)
- frames per second: 25
- keyframes: every 2 seconds, in other words: every 50 frames 
- audio sample rate: 48000 Hz

Windows Media live streaming settings

We advise using the following Windows Media Encoder settings:
- CBR (not VBR)
- Windows Media audio 9.2
- Windows Media video 9
- 25 Fps / keyframe 8 sec
- Buffer Size: 5
- Smoothness: 85
- Complexity: Auto

Smart Phones, iOS devices encoding settings

- video codec: H.264 baseline 3
- audio codec: AAC-LC
- frames per second: 25
- keyframes: every 2 seconds, in other words: every 50 frames 
- audio sample rate: 48000
- aspect ratio: 16:9
- max bit rate streaming 3G: 250Kbps (audio + video)
- max bit rate streaming WiFi: 1Mbps (audio + video)

General tips

Encode at a decent bit rate. A low bit rate means low quality. A high bit rate means that users may experience buffering issues. European and some Asian customers may have high speed links that allow for HD quality content. But for other regions and for corporate viewers you must keep the encoding bit rate under 750Kbps.

Low quality videos are encoded at 320x240 at 250-500Kbps.

Medium size quality videos are encoded at 720x400 at 500-1000Kbps.

High quality videos are encoded at 720x400 at 1-2Mbps
High Definition videos are encoded at 1280x720 at 3-8Mbps.

Make sure that the video size fits the encoding bit rate. Do not encode a 320x240 movie at 2 Mbps. Do not encode a 1280x720 movie at 500 Kbps.

De-interlace your content before transcoding. The quality improves significantly.

Use 2-pass CBR (Constant Bit Rate) encoding for a high quality streamable file. VBR is not recommended for streaming.

If you want to stream through our Darwin Streaming Services, make sure you 'hint' the videos.


What is the difference between HTTP live streaming and True streaming?

HTTP live streaming is a relatively new technology.

Instead of pushing an actual stream over proprietary RTMP or RTSP protocols, HTTP live streaming chops streams into small segmented files which are downloaded in realtime by the client. The client then stitches these chunks back together into a fluent stream.

True streaming protocols offer QoS and can offer QoE as well. HTTP streaming cannot offer QoS, only QoE.

The first benefit is that HTTP live stream better passes through badly configured firewalls. StreamZilla has actually optimized our RTMP, MMS and RTSP services so they can be tunneled over HTTP as well. So this is not a real valid argument.

The second benefit is that HTTP streams better adapt to the actual available end users bandwidth. Although True streaming for Flash, 3GPP, Windows Media and Real have offered adaptive bit rate streaming features, HTTP adaptive bit rate streaming is faster and works in a more reliable way. This enhances the Quality of Experience for mobile and OTT users.

Some claims about HTTP adaptive bit rate streaming are simply not true. They are not cheaper. Actually, HTTP adaptive bit rate streaming generates more overhead traffic than UDP based true streaming. HTTP adaptive bit rate streams are usually encoded with much higher bit rates, which generates more traffic. 

HTTP adaptive bit rate streaming is great technology but it is still in it's infancy. There are some issues with security, access management, encoder connections and access logging that we are not too happy with, whether it's for Apple's HLS, Microsoft's Smooth or Adobe's Zeri implementations.

Customer workflows, portals, players and end users clients haven't always been updated yet to support these new innovations. Switching to HTTP adaptive bit rate streaming is too risky. The service may fail, the workflow may fail, and there is the risk of not being able to reach the same market share as they can today with their existing protocols and services.

For these reasons, most of our customers stick with our 'traditional' true streaming services. They don't replace RTMP or RTSP or MMS streams with HTTP streams, they only add HTTP streams to the mix, for instance to support Apple iOS devices. 

So for reliable streaming we still recommend to use true streaming technologies. But feel free to try all our HTTP streaming services, we have included Apple HLS and Microsoft Smooth support all in our accounts and we offer some pretty advanced features compared to other HTTP streaming providers, like intelligent logical assets control, multiple bit rate streaming setup wizards and intelligent access log processing.


Why is streaming better than progressive downloads?

Downloading generally generates more traffic than true streaming. A progressive download is pushed at maximum speed to the viewers computer. Even if a viewer watches for just one minute, the entire 10 minutes video could have been downloaded. Streaming only generates traffic during view time, plus a small buffer. The costs for streaming traffic can be 10 times lower than with progressive downloads!

A download is actually copied to the end users harddrive. A stream is not copied, only the audio and video data are sent. Only a small buffer is in the memory of the client device. The asset can not be copied and re-distributed, unless someone uses a specific stream ripper application.

Streaming offers better Quality of Service control, better traffic management, intelligent bursting and buffering, random access, better reporting and of course live streaming features.

Some CDN's claim that they offer streaming support, but in reality they only offer progressive downloads to save costs. Some use intelligent download technologies to limit traffic, but these solutions never really match the benefits and efficiency of true streaming.

StreamZilla offers true streaming via MMS, RTSP and RTMP, and offers progressive download support as well. With StreamZilla there is no operational cost difference between progressive download and streaming, but the benefits are huge, and you can save dramatically on traffic costs, so we advise to use streaming delivery whenever you can.


Are there downsides to streaming?

If you want end users to keep a copy of your content, for instance for ringtones, podcasts and vodcasts, then downloading is the only option of course. For all other purposes we recommend streaming.

The downside of streaming protocols (RTMP, MMS, RTSP) is that they could be blocked or frustrated by corporate firewalls.

StreamZilla has enabled HTTP tunneling for all these protocols to bypass this issue!


What are the most popular media formats?

H.264+AAC for Flash and QuickTime. WMV for Windows Media and Silverlight. 3GPP for mobile content. FLV is for legacy Flash players. We advise to standardize on H.264+AAC. If you want to delivery content via RTSP, do not forget to 'hint' (optimize for streaming server) your MP4, MOV or 3GP assets.


What are the most popular media players?

Flash, Silverlight, Windows Media Player and 3G mobile clients. The market penetration of the latest versions of Flash and Silverlight are 60% in offices and schools and 75% at homes. Do not believe the >90% marketing claims. For maximum market penetration we advise to offer your content in H.264 and WMV via Flash and Silverlight.


Which on-demand streaming formats do the accounts support?

We support all popular streaming formats including MP4 (H.264+AAC), FLV, WMV, MP3, MOV, 3GP, M4V, F4V, ASF, WMA and WSX VOD streaming.


Which live streaming formats do the accounts support?

We offer integrated support for Apple HTTP Live Streaming, Microsoft HTTP Smooth Streaming, RTSP Windows Media Streaming, RTMP Flash streaming, RTSP H.264, 3GPP, QuickTime streaming and Icecast HTTP live streaming.

In our dashboard and through our API's you can setup streaming publishing points for all these technologies. Our wizards let you setup and configure the publishing points and offer encoder setup details. We support a wide range of live encoders.


Which live encoders do the accounts support?

We support Windows Media Encoder, Flash Media Encoder, QuickTime Broadcaster, Wirecast and Icecast compliant encoders. Compliant hardware and software encoders may work as well.


Do the accounts support web delivery?

Yes, all our servers also offer support for HTTP downloadable delivery of content. You can upload any file type including web pages, images, documents, media, applications, configuration files and zip files. We do not offer PHP, ASP, database or other application support.


Do the accounts support progressive downloads?

Of course. You can progressively deliver any media file via our service. Upload the assets to the wwwroot. In addition, for FLV files we offer a advanced progressive download feature that lets the viewer skip through the video even if the video is not downloaded. Note that in general progressive download generates more traffic than with streaming delivery and that there is less QoS control and less exact reporting compared to streaming delivery. Use our true streaming service whenever you can.


Does the wwwroot support server side scripts?

The wwwroot is for static assets. You can upload any static asset type. You cannot run applications, execute PHP, ASP, CGI scripts or run databases. Please use your existing web server(s) for applications and use our CDN for web acceleration and streaming.


Which delivery protocols do the accounts support?

We offer integrated support for true streaming protocols: Windows Media Streaming (MMS/RTSP) with advanced bursting, QuickTime, H.264 and 3GPP streaming (RTSP) with advanced bursting, Flash and H.264 streaming (RTMP) with advanced bursting.

We offer integrated support for Apple HLS and Microsoft Smooth Streaming.

We offer integrated support for advanced HTTP progressive download for MP4 files and HTTP progressive download for any file type.


Are the accounts optimized for firewalls and NAT?

Yes, all true streaming protocols are not just available on ports 554 (RTSP) and 1755 (RTMP) but also available on port 80 (the default port of HTTP) via TCP so streams are not blocked by firewalls or NAT routers.

If you still encounter issues with firewalls and proxies we advise to offer a progressive download option next to the streaming delivery options.

All HTTP live streaming protocols are by default available on port 80.


Does StreamZilla modify our content?

Absolutely not. We don't change a single bit. We respect your content and your quality levels. You have complete control over your content quality, sizes and bit rates. You encode your content, upload to our CDN and we distribute. We do not downgrade your content by transcoding or modifying your content.


Can I stream simultaneously VOD and Live?

Of course. Your account supports VOD and live streaming, and (progressive) download.


Can I stream multiple formats simultaneously?

Of course, you can mix multiple live and/or on-demand streams in any format.


Can I upstream/upload one format and you deliver in other formats?

We do not transcode, downgrade or modify vod streams or live streams. You can upload and upstream and we serve it out exactly the way you offer it to us. If you want to offer content in multiple bit rates or multiple formats, you are free to upload or upstream all variants to us and offer these to your audience.


Can I stream one format to many clients?


If you encode an MP4 live stream with H.264 video and AAC audio, then we can deliver this through multiple services to end users. The Wowza service is capable of trans-protocolling the stream via RTMP, Apple HLS, RTSP and Smooth Streaming.

If you encode an MP4 file with H.264 video and AAC audio, then we can deliver this through multiple services to end users. The Wowza service is capable of trans-protocolling the object via RTMP, Apple HLS, RTSP and Smooth Streaming.

If the file is hinted, it can be served via Darwin Streaming Server over RTSP to many clients. 


Which transcoders do you advise?

Great free transcoders are Windows Media Encoder, Adobe Media Encoder, QuickTime Pro. In the semi-professional range we prefer Sorenson Squeeze and Episode Pro. In the high range we advise Flip Factory or Rhozet Carbon Coder.