Recording presentations using layered keyframes

A non-transitory, computer-readable medium storing program instructions that, when executed by a processor, cause the processor to perform a method comprising:

• recording a sequence of document keyframes, a sequence of annotation keyframes, a sequence of video keyframes, and an audio stream;
• comparing corresponding keyframes of each of the sequence of document keyframes, the sequence of annotation keyframes, and the sequence of video keyframes, wherein each of the corresponding keyframes includes a keyframe and a next corresponding keyframe in sequence;
• and
• transporting document keyframes to a presentation video service in which differences between corresponding document keyframes are determined, transporting annotation keyframes to the presentation video service in which differences between corresponding annotation keyframes are determined, and transporting video keyframes to the presentation video service in which differences between corresponding video keyframes are determined, wherein across all three layers of keyframes, only when differences in a sequence of keyframes are detected will keyframes be transported, wherein the presentation video service generates layered keyframes from transported document keyframes, annotation keyframes, and video keyframes, and wherein the presentation video service combines the layered keyframes with the audio stream to generate a presentation video.

A system comprising:

• a recording session service that records a sequence of document keyframes, a sequence of annotation keyframes, a sequence of video keyframes, and an audio stream, wherein the recording session service compares corresponding keyframes of each sequence of recorded keyframes, wherein the recording session service transports document keyframes where differences between corresponding document keyframes are determined, wherein the recording session service transports annotation keyframes where differences between corresponding annotation keyframes are determined, wherein the recording session service transports video keyframes where differences between corresponding video keyframes are determined, and wherein across all three layers of keyframes, only when differences in a sequence of keyframes are detected will keyframes be transported;
• and
• a presentation video service that receives keyframes transported by the recording session service, wherein presentation video service creates a sequence of layered keyframes from the document keyframes, the annotation keyframes, and the video keyframes received from the recording session service, wherein the presentation video service creates a keyframe video by transcoding the sequence of layered keyframes, and wherein the presentation video service combines the keyframe video and the audio stream thereby forming a presentation video.