Transcoding templates define the format, quality and watermark setting to use when converting (transcoding) an original video into a conversion. These calls are used to create, list, edit and delete transcoding templates.
Templates are applied by the transcoder every time a new conversion is created.
Due to the computational intensity of these jobs, it takes a while before a conversion is created. As a rule of thumb, take 1 minute of processing time for every minute duration of the original.
Supported output formats¶
Our transcoder can create conversions in four widely used formats. The majority our transcoding jobs use the H.264 format, which has emerged as the market leading codec. It is being used from cell phones and iPods to online distribution and streaming to Bluray high definition videos.
The default transcoding templates for new accounts use the MP4 format. It offers excellent quality, plus great compatibility across devices. For example, these devices are able to play our MP4 videos:
- Desktop browsers, either using HTML5 or plugins like Adobe Flash, Microsoft Silverlight or Apple Quicktime.
- Mobile devices running iOS, Android, Windows Phone or BlackBerry OS.
- Settop systems like Boxee, Apple TV, XBox 360, PlayStation 3, Google TV and Roku.
The MP4 format uses AAC as the audio codec and H264 as the video codec. We use the H264 Baseline profile to maximize device support.
WebM video is a patent-free, royalty-free, high quality format with support across many browsers and devices. Along with H.264 it is being used to power the HTML5 video revolution. This format uses VP8 as the video codec, Vorbis as the audio codec and WebM as the container.
FLV, also known as Flash video, is an older codec that is provided to customers targeting older devices, slower devices, or other specific needs. This format uses the Sorenson Spark (H.263) video codec and MP3 audio codec. The quality of FLV conversions is poor when compared to H.264 but, again, this format is all about compatibility.
AAC is the audio-only version of our H.264 format. Use it to either encode and stream audio content, or encode and stream audio-only versions of video content. AAC is widely supported amongst web browsers, mobile phones, MP3 players and podcasting software.
Vorbis is the audio-only version of our Ogg format. It is a patent-free, royalty-free, high quality format with support across many browsers and devices. Use it to either encode and stream audio content, or encode and stream audio-only versions of video content.
MP3 is the industry standard for digital audio with support in nearly every device in existence. When applied to a video, the MP3 format indeed only extracts and converts its audio stream. The MP3 audio format is excellent if you have speech-heavy content (e.g. interviews or lectures) that should be distributed as podcasts.
The last template format is rather a placeholder for people who want to stream their original videos without our transcoder touching them. When this template is applied to a video, our transcoder merely copies it to our CDN.
In order to successfully stream your original videos through our servers, make sure you only use The MP4 file format, with AAC audio and H264 video. Additionally, there’s a number of common sense requirements yo should keep in mind:
- Use sane dimensions (240px to 1280px wide) and bitrates (200kbps to 2000kbps). A 5000kbps full HD stream will look great, but nearly nobody has the power computer and internet connection to smoothly play such a video.
- Use keyframe intervals in the range of 1 - 5 seconds. Bits on the Run players can only seek to keyframes, so large keyframe intervals will result in poor seeking results.