Inaccurate trimming
By Olga Krovyakova - modified May 24, 2021, created Juli 12, 2019
Q:->The start time does not coincide with the assumed begin time; its off by 5 to 10 seconds sometimes. The end time is perfectly correct. What may cause this inaccuracy?
A:-> Such a behaviour can be encountered with SolveigMM AVI Trimmer, SolveigMM WMP Trimmer Plugin, SolveigMM Video Splitter.
These products operate with K-Frame accuracy for AVI, ASF files.
Video sequence encoded usually consists of groups of pictures (GOP). GOP consists of Key frame (that is first one in GOP) and delta frames. Key frame is encoded independently as a statical picture but delta frames are predicted from K frame and can't be decoded without K frame.
Thus to provide a user with fast and a video quality lossless video editing, our products fulfill trimming tasks with K Frame accuracy.
That means that all output fragments will be started with K frame.
The scheme below depicts the difference between K-frame and Frame accurate editing:
Olga Krovyakova is the Technical Support Manager in Solveig Multimedia since 2010.
She is the author of many text and video guidelines of company's products: Video Splitter, HyperCam, WMP Trimmer Plugin, AVI Trimmer+ and TriMP4.
She works with programs every day and therefore knows very well how they work. Сontact Olga via support@solveigmm.com if you have any questions. She will gladly assist you!