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DIVX AVI to MPEG (SVCD) AUDIO SYNCH PROBLEMS
This has been an ongoing problem for me.
I am able to capture, using TIVO-like functions on my PC, directly to MPEG.
However, much of what I want to keep on VCD / SVCD / DVD is from commercial TV.
My card captures DIRECTLY to MPEG, but I can't remove commericals from such a format without losing audio synch. So, I've hit upon a multi-step pperation that *almost* works :
1) Capture the show directly to MPEG, using 640 x 480 video, with 128-224 kbps audio @ 44.1 kHZ
*** This step appears to work fine **
The resulting MPEG file keeps audio/video synch
2) xlate show to AVI format, that is either HUFFYUV or DIVX-encoded.
Have done this (at various times) with : mpegmediator, canopus procoder (1.01.35.0), and an mpeg-enabled version of Virtual Dub. I (generally) apply no filters, or xlations when going back to AVI at this point.
** This step appears to work fine **
The resulting AVI file keeps audio/video synch
3) Remove Commercials from AVI file.
Using VirtualDub to "cut out' the commercials, then write a NEW AVI out.
Typically using "full process" mode, and (at most) a brightness filter, the new AVI (either DIVX- or HUFFYUV-encoded) is now quite a bit smaller / shorter than the original.
(Amazing how much space and time commercials take up from even a "half-hour" show.)
** This step appears to work fine **
The resulting "shortened" AVI file keeps audio/video synch
===== LAST & FINAL STEP =====
4) xlate this AVI to an (S)VCD-compatible MPEG2, using Canopus Procoder and the appropriate target profile (MPEG2-SVCD_NTSC).
MPEG encoding is set to "highest quality" 2-pass VBR.
I "play" with the audio & video-bitrates so as to get and entire 1 hour (or 2 1/2 hour) shows a single 700 MB SVCD, but that is as I go in "tweaking" the settings.
The conversion appears to go off without a hitch.
HOWEVER, the audio/video synch of the resulting MPEG file is "broken".
Audio & Video line up near the beginning of the file, but audio starts to lag further and further behind as the file is played thru (any MPG file play will show this, as will my DVD player).
By the time you get about 1/3 of the way thru even a 1/2 hour TV-show recording, the result is *quite* noticeable.
Any ideas, anyone ?
The problem --- to my mind --- is almost certainly introduced in the last step (Canopus AVI-to-MPEG), I'm just not sure what parameters/options to look for.
I am able to capture, using TIVO-like functions on my PC, directly to MPEG.
However, much of what I want to keep on VCD / SVCD / DVD is from commercial TV.
My card captures DIRECTLY to MPEG, but I can't remove commericals from such a format without losing audio synch. So, I've hit upon a multi-step pperation that *almost* works :
1) Capture the show directly to MPEG, using 640 x 480 video, with 128-224 kbps audio @ 44.1 kHZ
*** This step appears to work fine **
The resulting MPEG file keeps audio/video synch
2) xlate show to AVI format, that is either HUFFYUV or DIVX-encoded.
Have done this (at various times) with : mpegmediator, canopus procoder (1.01.35.0), and an mpeg-enabled version of Virtual Dub. I (generally) apply no filters, or xlations when going back to AVI at this point.
** This step appears to work fine **
The resulting AVI file keeps audio/video synch
3) Remove Commercials from AVI file.
Using VirtualDub to "cut out' the commercials, then write a NEW AVI out.
Typically using "full process" mode, and (at most) a brightness filter, the new AVI (either DIVX- or HUFFYUV-encoded) is now quite a bit smaller / shorter than the original.
(Amazing how much space and time commercials take up from even a "half-hour" show.)
** This step appears to work fine **
The resulting "shortened" AVI file keeps audio/video synch
===== LAST & FINAL STEP =====
4) xlate this AVI to an (S)VCD-compatible MPEG2, using Canopus Procoder and the appropriate target profile (MPEG2-SVCD_NTSC).
MPEG encoding is set to "highest quality" 2-pass VBR.
I "play" with the audio & video-bitrates so as to get and entire 1 hour (or 2 1/2 hour) shows a single 700 MB SVCD, but that is as I go in "tweaking" the settings.
The conversion appears to go off without a hitch.
HOWEVER, the audio/video synch of the resulting MPEG file is "broken".
Audio & Video line up near the beginning of the file, but audio starts to lag further and further behind as the file is played thru (any MPG file play will show this, as will my DVD player).
By the time you get about 1/3 of the way thru even a 1/2 hour TV-show recording, the result is *quite* noticeable.
Any ideas, anyone ?
The problem --- to my mind --- is almost certainly introduced in the last step (Canopus AVI-to-MPEG), I'm just not sure what parameters/options to look for.
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