Type 1 and Type 2 AVI question

Archived from groups: rec.video.desktop,alt.video.dvd.software (More info?)

"Brian" <bclark@es.co.nz> wrote in message
news:eq1790lb8fvvfo8fkp85crfvq1n4a8athf@4ax.com...
> I'm trying to understand the difference between a type 1 and type 2
> avi file.
> It looks like there are more video editors that support a type 2 avi
> file. Is there any advantage in saving a video in type 1 avi?


" Type-1 vs. Type-2 DV AVI Files
DV cameras produce interleaved audio-video; each frame of video also
contains the audio information. If you save DV data to an AVI file, you have
a choice:

a.. Store the interleaved data as one stream in the AVI file. This is
known as a type-1 file.
b.. Split the interleaved data into separate audio and video streams. This
is known as a type-2 file.
For video capture, where maximum throughput is crucial, it is better to use
a type-1 file, because type-2 files carry redundant audio data. (The video
stream still has the audio data. The audio is simply hidden by labeling the
stream as video.) Also, writing a type-2 file requires some additional
processor time to split the interleaved stream.

On the other hand, type-1 files are less efficient for real-time editing.
The application must extract the audio from the interleaved stream, make the
edits, and interleave the data again. Also, the type-1 format is not
compatible with Microsoft® Video for Windows® (VFW). DirectShow can handle
both types of files. "

(from a Microsoft web page.)

As you can see, AVI 1 has the video and audio interleaved in the one file.



Robin.