after encoding, file balloons 3x

[uglijimus]

I have an mpg file

File : 788 MB (1.05 GB), duration: 1:28:59, type: MPG, 1 audio stream(s), quality: 60 %, ,
Video : 954 MB, 1500 Kbps, 29.970 fps, 352*240 (16:9), MPG2 = MPEG 2 (SVCD/DVD), Supported
Audio : 122 MB, 192 Kbps, 44100 Hz, 2 channels, 0x51 = Mpeg-1 audio Layer 2 [0xc0], , , Supported

It's only around 800 MB but after I encode it with ffdshow in VD using any container with any codec @1500 kbps, the file comes out to be 1.8 GB and quality not as good as the original.
Any idea why?

[poisondeathray]

ffdshow is not a good encoder for most codecs that it has listed (but great decoder), and 2pass encodes are often broken, leaving unpredictable filesize

It's fine for ffv1, ffd huffyuv , but these are lossless formats. Almost everything else is broken or based on old libraries. I would use another encoder

[manono]

Did you reencode the audio as well? To PCM WAV audio? Thus ballooning the final size?

[lordsmurf]

Why are you reencoding, anyway?

[Gavino]

File : 788 MB (1.05 GB), duration: 1:28:59, type: MPG, 1 audio stream(s), quality: 60 %, ,
Video : 954 MB, 1500 Kbps, 29.970 fps, 352*240 (16:9), MPG2 = MPEG 2 (SVCD/DVD), Supported
Audio : 122 MB, 192 Kbps, 44100 Hz, 2 channels, 0x51 = Mpeg-1 audio Layer 2 [0xc0], , , Supported

It's only around 800 MB but after I encode it with ffdshow in VD using any container with any codec @1500 kbps, the file comes out to be 1.8 GB and quality not as good as the original.
Any idea why?

Firstly, your original file size is not around 800Mb - 954+122=1078, so I don't know where you got 788 from.

Secondly, re-encoding without audio compression will give an audio bit rate of 1411kbps, or a total rate of 2911, which accounts for your final size of 1.8GB. So I agree with manono's diagnosis.

You need to set the audio processing to "Direct Stream Copy".
VD is fine and problem-free once you get into the habit of setting the ouput options properly for each encode.

[uglijimus]

@poisondeathray,

ffdshow may not be good for encoding, but it is the ONLY encoder I have found where I can put keyframes in every second. Also, I did try right clicking on the file for mediainfo to come up, but nothing did. No options to use mediainfo in any way. And I did download the windows 64 bit (i'm using windows 7 release candidate)

@manono, I did not re-encode the audio, I did a direct stream as I didn't need to do anything with the audio.

@lordsmurf, I have an episode of a program I want to put on a DVD that has commericals on it and I want to edit it out. When I tried with direct stream, VD said that it wasn't able to do a direct stream copy. I could use SUPER as I think that is the best encoding application out there, but again, I can't put keyframes in there so I can't make accurate edits.

@gavino, When I right click on the file and look at properties, it's a little over 800MB.

[poisondeathray]

I think you're going about this wrong way, since your end goal is DVD. Re-encoding with a lossy format will just cause quality loss.

Your source file is MPEG2. Virtualdub doesn't support MPEG2 natively and probably isn't the best tool for this goal, that's why it can't direct stream copy. Avidemux can (set video to copy, audio to copy, format to mpeg-ps, mark in/mark out, then press save including the extension in the name). Other alternatives to cut MPEG2 are: mpg2cut2, videoredo or womble mpeg video wizard. The last 2 are frame accurate and re-encode only the few frames around the cutsite if necessary

Virtually all encoders can set min/max keyframe interval. The settings are usually in the options. For a 29.97fps video, that's 1 keyframe per 30 if you want them 1sec

Also the problems your're having maybe related to Win7RC

[uglijimus]

thanks for responding,

actually, I'm not that concerned about the video quality as the program isn't the greatest quality to begin with.

avidemux has to be the worst program I have ever had experienced. It hasn't accepted one video I've put into it. And I've tried it on three separate occasions. I'll give a shot to the other ones you mentioned, they sound promising though I was hoping that VD could do everything.

<<Virtually all encoders can set min/max keyframe interval. The settings are usually in the options. For a 29.97fps video, that's 1 keyframe per 30 if you want them 1sec
>>

I've never seen any keyframe adjustment other than ffdshow and i've downloaded most encoders. so are you saying that if you encode at 29.97 fps the key frames will automatically become 1 keyframe per second? I know that can't be true cause after I encode a video, I pop it back it into VD and press the "next keyframe" button and it's usually 1 keyframe per 10 sec even after I've encoded it at 29.97 fps (not using ffdshow)

[poisondeathray]

actually, I'm not that concerned about the video quality as the program isn't the greatest quality to begin with.

All the more reason to conserve what you have. If it degrades anymore, you won't be able to see anything... yet get the point. On the other hand, if you're starting with a high quality source , like a blu-ray for example, you can much more headroom to screw around

avidemux has to be the worst program I have ever had experienced. It hasn't accepted one video I've put into it. And I've tried it on three separate occasions. I'll give a shot to the other ones you mentioned, they sound promising though I was hoping that VD could do everything.

Perhaps you're using an old build. Or perhaps it's related to Win7. It's much better suited to your specific task than vdub. No quality lost, and faster because no time wasted re-encoded.

I've never seen any keyframe adjustment other than ffdshow and i've downloaded most encoders. so are you saying that if you encode at 29.97 fps the key frames will automatically become 1 keyframe per second? I know that can't be true cause after I encode a video, I pop it back it into VD and press the "next keyframe" button and it's usually 1 keyframe per 10 sec even after I've encoded it at 29.97 fps (not using ffdshow)

Virtually all can.

xvid, divx, x264, HCenc....In fact, I can't think of one that doesn't You just haven't looked in the options, or the GUI's you've used are too simple to allow you to access those options. If you set the max key interval (it might be called I-frame interval or similar terminology) to 30, the highest will be 1sec apart, it might be closer together, unless you set the min interval. If min=max you get the exact placement setting. If you set min=max=1 , they are all keyframes. Note compression efficiency decreases with shorter intervals

Here is an example in the xvid vfw interface (what you would see if you used vdub). The xvid defaults are 300, so that would be ~10sec for a 29.97fps video. Note that is the maximum, it still dynamically places them, so they could be shorter intervals.

[uglijimus]

thanks for the info. I never realized that, or like you said never found it. those things you mentioned though, like xvid, divx, x264, HCenc, aren't they all codecs? That means I would still have to look for a program like VD or can I use these with vd? how can i get into the configurations of xvid like you showed in your post?

the keyinterval frame of course is important but so is change the aspect, ratio and frame rate and the audio properties too.

[poisondeathray]

Yes, there are some vfw versions that work in vdub, and other gui's that you can use them in. (But not hcenc, that's a mpeg2 encoder, it has it's own GUI that accepts avs scripts.) You can change things like aspect ratio, frame rate etc... sometimes through the encoder, or through scripts, BUT if your end goal is DVD, you have to keep it within specifications

You're going about this the wrong way. You need MPEG1/2 for DVD-Video (unless you have a DivX compatible standalone player) . It doesn't make sense to encode to something else just to edit, then encode back to MPEG2 when you already have a compliant source! Each conversion stage is lossy. You're wasting time, and losing quality.

If you wanted to do this the silly way, at least use a lossless intermediate like lagarith, or huffyuv. They are all I-frame so edits are frame accurate. You need lots of HD space, and you still lose quality when converting back to MPEG2.

VDub is a great program, but not for what you want to do...use the right tools.

[uglijimus]

thanks for all the info. I found the xvid codec, used it and was able to set up the keyframes. The quality was so bad though even though I had it on the highest setting. There's something about this mpeg. It doesn't react well to any encoding or editing. I used the mpeg2cut2, but the screen was black. Nothing would show up. I'm going to try the other two you suggested. I just want to get those commericals out of there!!

[ronnylov]

projectx can cut commersials and fix problemds in MPEG-2 file at the same time. The output will be demuxed, fixed and synchronized elementary streams redy for DVD authoring. No reencoding is done. I use GUI for dvdauthor to create a DVD from the commercial free output files from projectx.

[uglijimus]

thanks for all the help guys. I tried so many programs and it kept saying that the "pathway was not there" or something like that. Then I tried a program called Mpeg streamsplit or something like that which requires quicktime 1.81 alternative. I was able to cut the commericals out without re-encoding. Couldn't believe it, I was just about to give up.

[Nelson37]

If the error was "path not found" that means that somwhere you were pointing to a file that did not exist in that location.

From the number of progs which failed on this file, it must be either highly non-standard and/or corrupted in some way. One reason you need various tools for video, some handle certain errors better or simply ignore them.

[uglijimus]

it had japanese in the folder title, so that may have been a factor. the mpeg program i used that actually worked
had no problem with it though...