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| shanghaied |
| Posted: Sep 5 2002, 11:52 PM |
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Unregistered
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Hi,
I am a complete newbie, so I'll apologize now for the ignorance. I have hooked my VCR up to my computer and am trying to make a reasonable size encoding of a vhs. Anyway, I have two AVI files I need to merge with the following stats:
720x480
1563 Audio kbps
16 bit Audio sample size
PCM Audio Format
Frame rate of 29/sec
24 Bit Video sample size
DV Codec compression
Merging the AVIs was easy. But the two files together as-is are 3gigs (for about 14 minutes of footage). I'd obviously like to cut this size down drastically (<200 megs, hopefully). I've tried compiling the video using DIVX and audio using MP3, but on playback I received terrible flicker/distortion. What is the proper way of encoding the file to avoid these issues? I've also tried the steps below but had the same result.
Thanks,
Shang
1. Load the Video in VirtualDub (File open...)
2. Set Audio Direct StreamCopy
3. Set Video Full Processing Mode
4. Apply Filters if you need (you can also try without at first)
5. Set Video Compression Divx 5.02 (for example)
6. Fill in the calculated Bitrate (should be about 996 for a 85 minutes movie with sound @128kb mp3)
7. Set the other codec things if you like to
8. in the codec menu set "2pass first pass"
9. File save as avi "name1"
Then wait a bit (~one hour or so, depends on your hardware and filters etc..)
10. Set Video Compression Divx5.02 "2pass second pass"
11. File save as avi "name2"
wait for the second pass
12. File Open "name2" in VirtualDub
13. Set Audio Full Processing Mode
14. Set Video Direct stream Copy
15. Set Audio Compression MPEGLayer 3 128kb
16. File save as avi "final" |
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| Ciler |
 Posted: Sep 6 2002, 06:22 AM |
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Is it possible for you to put up here a screenshot of your compressed movie. Because, so far, I only see one reason for Virtual Dub to distord the picture while compressing, that can be easily indentified by viewing one of the distorded picture.
BTW, This sometimes occurs when using filter "null transform" for cropping. |
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| Tut_Ank |
| Posted: Sep 6 2002, 08:01 AM |
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| QUOTE (shanghaied @ Sep 5 2002, 05:52 PM) | ...
1. Load the Video in VirtualDub (File open...)
2. Set Audio Direct StreamCopy
3. Set Video Full Processing Mode
4. Apply Filters if you need (you can also try without at first)
5. Set Video Compression Divx 5.02 (for example)
6. Fill in the calculated Bitrate (should be about 996 for a 85 minutes movie with sound @128kb mp3)
7. Set the other codec things if you like to
8. in the codec menu set "2pass first pass"
9. File save as avi "name1"
Then wait a bit (~one hour or so, depends on your hardware and filters etc..)
10. Set Video Compression Divx5.02 "2pass second pass"
11. File save as avi "name2"
wait for the second pass
12. File Open "name2" in VirtualDub
13. Set Audio Full Processing Mode
14. Set Video Direct stream Copy
15. Set Audio Compression MPEGLayer 3 128kb
16. File save as avi "final" |
About the flickering: I hope you have not used the ACDsee filter which enhances individual light/colour frame by frame but causes flickering when seen the movie as a whole.
A couple of comments/suggestions:
steps 1-5 unchanged.
6. Fill in the calculated Bitrate (should be about 996 for a 85 minutes movie with sound @128kb mp3)
for a movie 720x480 @ 29fps 996 is way too low:
720*480*29*.17=1700 kbps
(0.17is the minimun bits/pixels to get good quality divx/Xvid)
if you want to fit 85 minutes you should lower the resolution, go for two cd's, lower audio quality or all of the above.
I suggest:
audio CBR MP3 96Kbps (*85min) 62 MB (CBR means lower quality but it can be used in avi; VBR can be used, but not recomended);
that leaves 638 MB for video ( on a 700 Mb CD);
((638*1024/85)/60)*8=1024 kbps as a bitrate.
to get nice quality with this bitrate I'll use 512x384 this gives you a perfect 4:3 ratio and both are multiples of 32 that makes tor a nice compression speed and better quality. Use 1000kbps as bitrate: 1000*1000/(512*384*29)=0.175 bits/pixel
if you want more resolution, go for 2cd.
7. Set the other codec things if you like to make sure to set the RC ans half the number of frames the video has to optimice the bitrate distribution.
8. in the codec menu set "2pass first pass".
9. File save as avi "final" add to job list and defer procesing
10. Set Video Compression Divx5.02 "2pass second pass" Set Audio Full Processing Mode, Audio Compression MPEGLayer 3 96kb
11. File save as avi "final" add to job list and defer procesing.
12. job control... start. wait for 1st and 2nd pass with audio compression to be done. All unatended.
13. check quality.
if you have a 14 minutes footage you can do the calculations yourself, just try to keep the bits/pixel ratio between 0.225 and 0.170.
It's up to you, but for me lower sesolution and high quality is better than more resolution and lower quality/more artefacts.
Hope it helps.
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| shanghaied |
| Posted: Sep 6 2002, 11:34 AM |
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Thanks guys. Actually, I realized it was because I was using the Divx 5.0 codec instead of 5.02. The video works great in 5.02, but now I've seem to have no audio  . Perhaps I need a different MP3 codec? |
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