Re: Slow performance in the ConcatSameSize demo

I’m considering purchasing your multimedia product because it seems to do exactly what I need. I need to join multiple video clips, of a users choice, together into one file. I must be able to support DivX, mp4 and wmv/a. I am writing a web application in c# (.Net).

I have downloaded the evaluation version of your product, however the “ConcatSameSize” example seems to be working very slowly. I have tried joining two DivX files which are about 5 minutes each. The sample application works fine except that it takes about 7 minutes to complete. This is way too long to suit my needs. My users will most likely be selecting more than 5 files each.

I would very much like to purchase your product, is there a way to speed this process up considerably. I don’t need to convert formats or do any other processing, I just need to join clips. I just need to go from DivX to DivX or from mp4 to mp4 or from wmv to wmv.

Any help would be appreciated.
Jon

Re-encoding video files is a time consuming operation. The problem with concatenation is that both files must be split into individual samples (frames), then re-combined into one file. Unfortunately, this is true even if both original clips used the same video format and compression type.

Generally, the speed of re-encoding depends on:
1. Processor speed and memory.
2. Codecs used in de-compressing and compressing videos.
3. Resolution of the video.

You should get better results in improving the first point (use a faster processor and increase RAM).

Using a different codec can also improve results, but you find which codec gives best results only by doing some tests.