This document describes Kwiktec AdServer Setup approach and function overview.
Companion Ad: Commonly text, display ads, rich media, or skins that wrap around the video experience. These ads come in a number of sizes and shapes and typically run alongside or surrounding the video player.
InLine Ad: VAST document that includes all the elements necessary to display the visual experience of the ad.
Linear Video Ad: The ad is presented before, in the middle of, or after the video content is consumed by the user, in very much the same way a TV commercial can play before, during or after the chosen program.
Non-linear Video Ad: The ad runs concurrently with the video content so the users see the ad while viewing thecontent. Non-linear video ads can be delivered as text, graphical ads, or as video overlays.
Primary Ad Server: First ad serving system called by the Video Player or other framework. It is assumed that in most cases a publisher will make all initial ad requests through their Primary Ad Server (whether homegrown or third party), then redirect to other ad servers as needed.
Secondary Ad Server: Ad server used by an ad network or by the buyer of ads to serve creative, track results and optimize creatives.
VAST (Video Ad Serving Template): XML document format describing an ad to be displayed in, over, or around a Video Player or a Wrapper pointing to a downstream VAST document to be requested.
Video Player: Environment in which in-stream video content is played. The Video Player may be built by the publisher or provided by a vendor.
Wrapper Ad: VAST document that points to another VAST document from a different server.
Are compressed videos that take up less space than the full res files, but are hi res “enough” that they make great quality highly compressed videos. Kwiktec uses these files for Transcoding.
Transcoding is the direct digital-to-digital conversion of one encoding to another. Kwiktec does this as part of the ingestion process to convert the Mezzanine file to the various encodings required for streaming.
This profile is generally targeted at light applications such as video conferencing or playback on mobile devices with limited processing power. It provides the least efficient compression among the three choices, and at the lowest CPU overhead on decoding.
This profile has more capabilities than Baseline, which generally translates to better efficiency; yet it comes at the cost of a relatively higher CPU overhead (though less than the High profile). This profile is usually used in medium-quality web video applications.
This is the most efficient profile among the three. It has the most capabilities that pack more quality into a given bit rate, yet it is also the hardest to process because of these added operations. Though originally intended only for high-definition applications such as Blu-ray, this profile is increasingly becoming popular for web video applications
Key Frame Interval (I-frame)
A key frame in filmmaking is a drawing that defines the starting and ending points of any smooth transition.
For dynamic streaming also known as adaptive streaming:
Keeping a constant video keyframe interval instead of a variable keyframe interval ensures that the keyframes in the streams are not very far away from one another. Since the server switches streams on a video keyframe, having them too far away could cause a delay in the switch to happen on the server side.
I-frames are the least compressible but don’t require other video frames to decode.
P-frames can use data from previous frames to decompress and are more compressible than I-frames.
B-frames can use both previous and forward frames for data reference to get the highest amount of data compression.
A sequence of video frames, consisting of two keyframes, one forward-predicted frame and one bi-directionally predicted frame.
There are three types of pictures (or frames) used in video compression: I-frames, P-frames, and B-frames.
An I-frame is an ‘Intra-coded picture’, in effect a fully-specified picture, like a conventional static image file. P-frames and B-frames hold only part of the image information, so they need less space to store than an I-frame, and thus improve video compression rates.
A P-frame (‘Predicted picture’) holds only the changes in the image from the previous frame. For example, in a scene where a car moves across a stationary background, only the car’s movements need to be encoded. The encoder does not need to store the unchanging background pixels in the P-frame, thus saving space. P-frames are also known as delta-frames. A B-frame (‘Bi-predictive picture’) saves even more space by using differences between the current frame and both the preceding and following frames to specify its content.
URL Token Authentication
Token authentication allows you to generate secured links with expiration time.
Secured links provide content only within desired period and only to visitors having the links with the secure hash.
It is not possible to download secured content without valid (unexpired) hash from the CDN resource.
After the expiration time the links are unavailable and new ones must be generated in order to download the secured content again.
The Player is the name of Kwiktec media player that allows for a single implementation to support both iOS streaming in HTML5 and the traditional Flash player.
Each Kwiktec Ad server client is assigned an API Key that is essentially a password used to gain access to the Kwiktec AdServer API.
An Application Alias is a reference to an Application Configuration stored on the Kwiktec platform. This controls the settings e.g. Look and Feel, Advertising, Analytics, Security plus many other features of the application and or player. The Application Alias is used to generate your session token for all secure interactions with the AdServer API.
An endpoint is the entry point to a service provided by the AdServer API.
VAST (Video Ad Serving Template)
XML document format defined by the IAB for describing an ad to be displayed in, over, or around a Video Player or a Wrapper pointing to a downstream VAST document to be requested. Kwiktec support both VAST 1.0 and 2.0 implementations. See: IAB VAST for more information.
VPAID (Video Player-Ad Interface Definition)
The VPAID standard is to address known interoperability issues between publisher’s video players and different ads when the video ad is expressed in innovative formats (such as non-linear and interactive ads) that require a high level of communication and interaction between the ad and the video player. See: IAB VPAID for more information.
Cue Points are invisible markers in a video file which can be used to trigger external events such as:
Synchronising graphics, subtitles, etc.
Providing navigation options.
A tag is made of metadata comprised of a non-hierarchical keyword or term assigned to content in Kwiktec. Machine tags are metadata tags that use a special syntax to define extra information about a tag.
Machine tags have a namespace, a predicate and a value.
The namespace defines a class or a facet that a tag belongs to (‘music’, ‘movies’, etc.)
The predicate is name of the property for a namespace (‘genre’, ‘classification’, etc.)
The value is the value (‘pop’, ’R’, etc.)
There are no rules for machine tags beyond the syntax to specify the parts of a machine tag. This gives a very flexible approach to meta-data to cater to a diverse range of client needs.
External Articles on Machine Tags
Flickr: Discussing Machine tags in Flickr API
REST (Representational State Transfer)
REST, or Representational State Transfer, is a standard way of accessing data stored in a remote system over HTTP. Kwiktec uses this standard for applications and developers to access media information in an XML, JSON or JSONP format via the AdServer API.
Recommended Video Ad Ingestion/Mezzanine File Format
Video Type: H.264
Size/Ratio: 1920×1080 (16:9) 1440 x 1080 (4:3)
Video Bitrate: 4096kbps (low motion) or 6144kbps (Main motion) Main or High profiles
Key Frame Interval: 75
Audio Type: AAC
Audio Sample Frequency: 44.1kHz
Audio Bite Rate: 192kbps