pre-transcode

why pre-transcode?

If you go to the broadcast page and start streaming a file or DVD, the Veetle broadcasting software will transcode your video into the h264 format. This places an immense burden on your computer's central processing unit (CPU). Only the most expensive quad core CPU's are able to smoothly transcode to a high resolution output.

An option for old computers to broadcast at high, even HD, resolutions is to pre-transcode your video into an h264 video before it enters Veetle's website. This way, Veetle would only be responsible for streaminging the video over the Internet, which is a simple task that any old computer can handle.

software for transcoding

graphics card

On the bleeding edge of transcoding is software that can use your graphics processing unit (GPU). The reason for using GPUs to transcode videos is that the GPU has hundreds of stream processors compared to the CPU's maximum of four. In addition, GPUs can perform graphics operations such as matrix multiplications more efficiently than CPUs.

One of the only GPU transcoders out there is Badaboom. It requires an nVidia graphics card, 8 series or above. It can transcode 720p to another 720p h264 video at more than 3 times the original framerate of the video! This means that if your video were 3 hours long, it would take less than 1 hour to transcode! The problem with Badaboom is that it's relatively new and it doesn't let you configurable many settings, which results in poor image quality during fast moving scenes.

If you don't have an nVidia GPU, then you likely have an ATI GPU. ATI has a free software called Avivo to transcode video. We don't have much experience with Avivo, so we can't personally comment on its effectivness over Badaboom. However, reviews have said that Avivo is faster but buggier than Badaboom.

central processing unit

If you don't care about transcoding at bleeding edge speeds and care more about the final video quality, then consider transcoding with your central processing unit (CPU). But be warned: you may spend up to 5 hours transcoding a single 720p movie on the CPU. By sacrificing speed, you get better image quality because CPU transcoding software is well established and is easier for programmers to develop. The best CPU's for transcoding are quad cores. We recommend the Intel Corei7. It's a ton of horsepower at a bargain price.

If you're a big nerd, then you'll probably want to use x264 on FFMPEG. Since you're so nerdy, I won't need to tell you how to use it.

For the rest of us there is an easy to use CPU encoder called Handbrake. It's free and is supported on all major operating systems. Here are suggested settings for downsampling a 720p video:

Slower, good quality

 -i E:\input.mp4" -t 1 -c 1 -o "E:\output.mp4" -f mp4 -w 960 -l 544 -e x264 -b 900 -2  -a 1 -E faac -6 stereo -R Auto -B 96 -D 0.0 -x mixed-refs=0:8x8dct=0:trellis=2:b-adapt=2:direct=auto:me=umh:no-fast-pskip=1:merange=32:ref=5:subq=9:vbv-maxrate=1000:vbv-bufsize=2000:rc-lookahead=60:bframes=5 -v 1

Faster, average quality

 -i E:\input.mp4" -t 1 -c 1 -o "E:\output.mp4" -f mp4 -w 960 -l 544 -e x264 -b 900 -2  -a 1 -E faac -6 stereo -R Auto -B 96 -D 0.0 -x mixed-refs=0:8x8dct=0:trellis=0:b-adapt=2:direct=auto:me=umh:no-fast-pskip=1:merange=24:ref=3:subq=7:vbv-maxrate=1000:vbv-bufsize=2000:rc-lookahead=50:bframes=5 -v 1

transcoding suggestions

Format: Veetle works best with the MP4 container format. The video encoding should be h264. The audio encoding is not important; Veetle can handle most of the popular types.
Bitrate: Keep it under 1,000 kbps. You may not have a fast enough Internet connection to broadcast over this rate or your viewers may not have enough bandwidth to watch your channel smoothly over this rate.
Resolution: Keep it under 1280x720. Many viewers don't even have screens that can play 720p video. Keeping it lower resolution will also allocate more bits per pixel, resulting in less artifacts.
2-pass: Turn it on. When 2-pass is turned on, transcoding time will nearly be doubled, but final quality should be much better. On the first pass, the software will analyze which scenes are fast moving and which are slow. Then on the second pass, it will assign more information to the slow moving scenes and less to the fast moving ones. That's because the human eye tends to not deeply analyze the quality of fast moving scenes, so it would be a waste of space to assign a lot of information to these scenes.
B-frames: Do not turn on pyramidal B-frames. It will cause your stream to stutter.

broadcasting the transcoded video

Once you've finished transcoding, go to the broadcast page. Click the big file button and select your file. In the next screen, select the use super advanced command line option and replace the code with the following:

#duplicate{dst=standard{access=http,mux=asf,dst=localhost:1234}}

Basically, we've removed the transcode part because your video is already transcoded. Finally, put your channel on air and enjoy HD streaming without an extreme gamer's computer!