Papajohn (?) - Audio Problem

[eeyore]

I have a Canon MV730i camcorder

up till now I have used DV-AVI typeI to store my source files but
decided to give a bit of a go to wmv.
I have been capturing the source via firewire to wmv(2.1 MBPS PAL -
720x576) via MM2 - - the sound suffers frequent clipping when played
via WMP10

That same source file is then processed through MM2 to a rendered movie
wmv(2.1 MBPS PAL 720x576) and the problem goes away.

A check with GSPOT shows the same format info, same codec information.
The only difference I can see is that the rendered file (48.6MB) is
slightly larger than the captured source file (48.5MB)

Any Ideas?

While it is not a big deal to me I am interested to know if anyone knows
of any differences.


Eeyore

 

[Rehan]

Without analysing the video one can only make a guess... My guess is that
the audio in the originally captured movie is compressed with more heavy
compression while it gets compressed less heavily in the WWM rendered movie.
(This also explains slight increase in file size)

 

[eeyore]

Without analysing the video one can only make a guess... My guess is that
the audio in the originally captured movie is compressed with more heavy
compression while it gets compressed less heavily in the WWM rendered movie.
(This also explains slight increase in file size)

Hi Papajohn;
I was hoping since the movie is captured from the cam via moviemaker
using a standard profile and the movie was saved by Moviemaker with that
same profile that the conditions would be known without a full review of
the source itself.



Eeyore

 

[Rehan]

First, I am not Papajohn...

I was hoping since the movie is captured from the cam via moviemaker using
a standard profile and the movie was saved by Moviemaker with that same
profile

There is no substitute to full review of source... as it matters what type
of audio and video you are capturing using those profiles.

The guess I made was made on the observation that you are compressing the
video and audio using a "lossy" compression profile. There is no gaurentee
that the result of second pass would be the same as first pass through the
same profile. The first pass throws away some info (albeit unnoticeable)
during compression while the second pass throws away some more info during
its compression. Hence the difference.

What do you think.

 

[eeyore]

First, I am not Papajohn...




There is no substitute to full review of source... as it matters what type
of audio and video you are capturing using those profiles.

The guess I made was made on the observation that you are compressing the
video and audio using a "lossy" compression profile. There is no gaurentee
that the result of second pass would be the same as first pass through the
same profile. The first pass throws away some info (albeit unnoticeable)
during compression while the second pass throws away some more info during
its compression. Hence the difference.

What do you think.

Yup...I should have got that on my own....
Thanks Rehan.

Eeyore