The invention discloses a decoupling type recording and
broadcasting method and
system based on a
key frame index and difference additional recording, and the method comprises the steps: firstly continuously collecting multiple paths of audio and video streams, segmenting the audio and video streams into video fragment files, meanwhile, carrying out the parallel real-time detection of a board key event, and generating a
key frame index file in which an
event type and a
millisecond timestamp are recorded; after class, according to the effective starting and ending time of the actual course and the index file, precisely extracting videos of corresponding time periods from the stored fragments; if fragment missing is found, fragments of other
machine positions in the same time period are searched based on indexes, patch video fragments are generated through frame-level difference encoding, finally, the patch video fragments and normal video fragments are spliced to form a complete classroom
record, and through a decoupling architecture of full-amount recording, event indexing, post-event accurate extraction and additional difference recording, the complete classroom
record is obtained. According to the invention, the problem of missed recording and wrong recording caused by equipment
delay, class schedule change or recording interruption in the prior art is solved, and the integrity of recorded content, the
time alignment precision and the
system fault-tolerant capability are remarkably improved.