Can you frameserve and use a lossless codec at the same time?

[christopheramos]

Hello,

I'm frameserving a MPEG TV show through Vdub and TMPGEnc (to clean it up). The input size is big (about 1/2 a gig -- 500+ MB).

When I frameserve, I will no doubt get a much bigger output file.

Is it possible to frameserve and use a lossless codec at the same time? Or is it best to frameserve first, then take the output file and run it through Vdub using the lossless codec?

Thanks!!!

[Caple]

If you are frameserving you are not using any codec.
I would load the file on vdub, set the filters I want and frameserve it to TMPG.
The experts can reply with better descriptions, I don't use vdub's frameserv so much, but frameserving is frameserving...

[christopheramos]

I was under the impression that a lossless codec (such as Lagarith) was used through Vdub or Vdub Mod. I might be mistaken. Maybe it can be used as a standalone application.

[guns1inger]

Frameserving sends uncompressed video directly to the reading application via a sign-post file. This file is very small, and is there simply for the reading application - in your case tmpgenc - to load.

The idea is that you load the avi into virtualdub, add your filters (resize, cleanup etc), and frameserve to your mpeg encoder so that the filtered version is encoded directly to mpeg without the need to save it as a temporary file.

The advantage is obvious - no intermediate save, no intermediate compression, no extra files taking up space.

The disadvantage comes from multi-pass VBR encoding because thefilters wuill have to be run through for each pass. While this is similar to encoding from a timeline in Premiere or Vegas, for long videos with a lot of filters it might be a better option to save to a lossless format prior to encoding. I have just finished working with a file almost 2 hours in length. I used avisynth to filter, and a single pass took almost 10 hours on my machine. A multi-pass encode was going to take 30 hours. By saving a single pass to a lossless format first, then encoding this, I was able to get the process down to around 14 hours.

For a 1 pass encoding, frameserving has many advantages.

[BJ_M]

often times you can turn off 'some' of the filters for the first pass - and turn them back on for the final pass (not resizing though - or cropping)

[guns1inger]

Would this not affect the analysis, especially if you are doing heavy noise reduction ?

[Nelson37]

Christopher, I have several questions about what you are trying to do.

You speak of additional processing of the "output file". The output file should be the end product, final stage, done. The processing should be all done BEFORE or DURING the frameserve to TMPGenc for encoding. You only want to encode ONE TIME for best quality.

You have a 500 Mb file and you think that is Big??? Even for a half-hour, that is nowhere near Big as far as video goes. In fact, assuming a one-half hour show, that is near VCD bitrates, or, as MPG goes, quite a bit on the small side. If longer than one-half hour, then there is something seriously wrong with the capture process.

[BJ_M]

Would this not affect the analysis, especially if you are doing heavy noise reduction ?

if really heavy - yes , a bit ...

each pass looks at motion vectors - so if they stay the same -- all is ok ... if there is tons of noise though , it would effect the motion analysis -- though in effect (if consistent noise) it would raise the bitrate the same throughout within the limits of the avg ...

[Scorpion King]

Hello,

I'm frameserving a MPEG TV show through Vdub and TMPGEnc (to clean it up). The input size is big (about 1/2 a gig -- 500+ MB).

When I frameserve, I will no doubt get a much bigger output file.

Is it possible to frameserve and use a lossless codec at the same time? Or is it best to frameserve first, then take the output file and run it through Vdub using the lossless codec?

Thanks!!!

Christopheramos, you said a few things that might need cleared up. ok. I'll try.

You have a MPEG video you are frameserving. MPEG is considered a final product. Reencoding mpeg files is considered to take a big hit in quality. I've done it, we all have done it, but It's much better to do all this with an AVI file instead. Frameserving an AVI file to Tmpgenc encoder is a fairly normal operation. Frameserving an MPG file out of VD to Tmpgenc isn't actually my usualy workflow...

"To clean it up", you said. Again, it is far better to capture AVi if possible if you plan on using filters/etc during processing. That might not be possible, I don' t know, but it is better IMO.

As said above.. 500MB isn't big, expecially after you work a few video files. 500GB is big. lol

"When I frameserve, I will no doubt get a much bigger output file.", you say. You will if you are sizing up and/or increasing the bitrate. In your case you have an MPG file to start with, then reencoding in Tmpgenc to some larger / higher bitrate video file. Again, we've all done it, but we don't advise it because you're going to take a quality hit. The information just isn't there on an upsize. IMO. Again, I've done it....

Hope this helps.
Good luck.

[edit] sorry I repeated what has already been said. Guess I watched tv too much while writing this. Got behind....

[christopheramos]

Okay, thank you guys. I will give it a shot. My input video is PAL, but for some reason, the output is much more narrow than it is tall after I process it. This is without me making any adjustments to the frame setting.

I've found that if I set the output to 4:3 display, full screen w/o keeping aspect ratio, the output file appears okay in terms of it's width and size. It has some black boarders that it didn't have before, so I use a null transform filter in Vdub.

I'm really only running the MPEG through VDubMod to deinterlace it. The output ends up with some noise, so I add a denoise filter in the Vdub filter chain to take care of that.

I was guessing that, since the input file was 500 MB, the output file after processing would be larger. In fact, it's turned out to be 1.5 GB.

This is where I began to consider reducing the output through Lagarith or some other losselss codec. In the alternative, I suppose I could build my output TV shows on a dual layer DVD, and still be able to fit several episodes onto a dual layer disc, without the need to reduce it's overall size via more compression.

I don't understand the advantage of frameserving and setting the output to .avi. I thought that I should be setting the output to MPEG-2 for DVD, as that is my ultimate goal.

[guns1inger]

Again, frameserving is just a method of passing uncompressed video from one place (in the case Virtualdub) to another (in this case tmpgenc). The avi is a signpost file. Something for tmpgenc to open so it thinks it has a file to process. It is tmpgenc that produces the mpeg video, not virtualdub.

File size has increased only because you are using a larger bitrate than the original had when you encode. If you post a screen shot from g-spot showing the original mpeg, we might be able to tell you what is happening with the resolution and bitrate.

[christopheramos]

Okay, but I'm just going from Mpeg to Mpeg. So I only use VdubMod to apply filters.

I wonder if I can just feed the file into TMPGEnc Plus, apply some of it's internal filters (such as denoise, deinterlace, and clipping [cropping]), and not have to worry about VDub.

Would that work?

[KBeee]

You can do that, but quite often TMPGEnc's filters are slower than VDubs, and also more limited.

What is the final destination of this movie you're cleaning up? And what is the original resolution?
If it's for watching on TV, then different settings in TMPGEnc will be needed than if you're planning to watch it on your computer. If the movies aspect ratio looks ok on your computer (square 1:1 pixels), then you'll need to make it 10% wider to display properly on your TV i.e. 640 X 480 on computer should be 704 X 480 for TV. TMPGEnc will do this automatically if you set the source and output ratios correctly.

[christopheramos]

What is the final destination of this movie you're cleaning up? And what is the original resolution? I think the resolution is 352x288. I want to play it on DVD/TV ultimately.


Okay, I will re-size by 10%. Thanks!

[KBeee]

352 X 288 indicates a PAL mpeg movie. You'll probably find it's also 25 frames per second.
If you have a player/TV capable of displaying PAL DVD then 352 X 288 will display fine on your TV. If you DON'T have a multi-standard setup, then you might need to look up some threads about PAL to NTSC conversion.

[christopheramos]

KBeee,

You are right, it's PAL and at 25 fps. I've played PAL on my standalone DVD player and TV before, and they played fine. So maybe you are right, maybe I won't have to fool with converting.

Thanks!!!!

Does anyone know how to take an output file and build a quick and easy DVD to test it out? So that I can be sure, without spending a lot of time authoring the MPEGs only to find out they aren't set right???

[KBeee]

You could use TMPGEnc to cut a 5 minute clip from your file and
TMPG Dvd Author will take that 5 minute 352 X 288 clip and author it fine as a PAL DVD. It will convert the audio from 44.1 to 48k to make it DVD compliant if needed. A short 5 minute clip burned to a RW-DVD should enable you to see if everything's ok.

[christopheramos]

Great! Thanks! I will give that a shot!

Thanks so much!