Which video formats, codecs and bitrates work best for playback in Ustream Producer?

Ustream producer can recognize .mov .mp4 .avi and .wmv file formats. 

If Producer recognizes the file format of the video, the next step in ensuring that you have the CPU capability to decode the video file and encode your stream to Ustream at the same time. If you are finding that your video is stuttering or choppy (dropping frames) then you may need to re-encode your video to make it more compatible with producer. 

There are two great free programs you can use to do this:

With both of these programs, you can convert incompatible file types to one that Producer will recognize, as well as change the bitrate, frame size, codec and other settings of your video. 

In order to get the best picture quality and best performance, you will need to do some experimentation, as it is highly dependent on your source video file and also the capability of the CPU and graphics card you have. 

As a starting point, we would recommend H.264 and AAC for Codecs and MP4 for the file type. 

Ideally the frame size of the video matches your output frame size so that no scaling is occurring.  For bit rate of the encoded video files, it is best to find a sort of "medium" quality.  You probably want it higher than your broadcasting bitrate so that their isn't too much degradation / encoding artifacts from the multiple passes, but if you set it too high, the CPU can struggle to re-encode it down to the broadcasting bitrate. 

For example, if the source file was encoded at high resolution: 1920 x 1280 and extremely high bit rate: 25Mbps, then just reading the video will be extremely taxing on the CPU, and the encoder will likely have to drop the frame rate in order to keep up with encoding in real-time.

In other words, if you plan to broadcast at 640 x 360 @ 800Kbps then 640 x 360 at 1-2Mbps might be good for the source file. If you're using a Mac, with an Intel i7 CPU, from what we've seen, 1280 x 720 @ 2Mbps H.264, AAC, .mp4 is about as big of a source file that can work well with Producer. At this resolution and bit rate there are usually no obvious encoding artifacts and the file size is small enough that the CPU does not need as many cycles to read the input and can devote more cycles to encoding the output.

The best thing to do is to do tests with a different types of source files and the encoding computer that will be used for the broadcasts. 

Once you find the sweet spot for your system, save this as a preset in your conversion software, and re-encode all your source files to the same file type, codecs and bitrates that perform well on your computer. 

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