Full video file takes 10 hours to encode using TMPGEnc. Why?

[lizardfish]

Why is it some of my avi videos take forever to encode when using TMPGEnc plus? I have one avi video for example that is 665 MB and when I run TMPGEnc plus it’s telling me it will take 10 hours to complete. Should I change the environmental settings? I have played with that with successful results with other problem files. Any help would be great. By the way the file is a high quality file perhaps that is why?

[theDruid]

TMPGEnc is well known as quite a slow encoder in general, and the time it takes depends on all sorts of things - for example:

* your PC - especially CPU, and to some extent RAM, bus-speed etc..
* the source file
* quality settings in TMPGEnc
* the output format

If the source file has a very different resolution to the output, it will take longer to do the resizing (not much, but perhaps a bit!)

Some codecs are more 'complex' than others in terms of decoding the source file in order to encode it again in TMPGEnc.

Of course, the playtime of the source file is very important - by saying your source is 665 MB, you're not telling us how long the actual video is - this depends on how highly compressed your source is.

The actual settings in TMPGEnc can make a huge difference - the Noise Filter settings especially, and Motion Precision.

Are you doing multi-pass VBR encoding by any chance? The multiple passes obviously mean it's going to take longer.

There are a lot of different factors which can influence how long it takes.

What do you regard as normal in terms of TMPGEnc's encoding time?

cheers,
mcdruid.

[bugster]

10 hours is not exceptional. Even with a P4 2.8 and 512Mb ram some of my encodes can take that long for a 2 hour movie. to DVD with high quality settings but no filters.

[Solarjetman]

Well overall TMPGEnc is one of the slower encoders. But the speed of an encode varies greatly depending on what settings are used and the nature of the video.

For instance, encoding a full DVD resolution video (720x480 NTSC) is going to take longer than an SVCD video (480x480 NTSC).

Also Mpeg2 seems to take more time than mpeg1.

The bitrate used also may affect the time.

Any filters you apply to the video are agoing to drasically increase the amount of time as well. Filters like noise reduction and smoothing can someimes even double the amount of time needed.

And finally, TMPGEnc has a quality setting. If speed is an issue, try reducing this. I see very little difference between highest and second highest myself (assuming your bitrate is high enough).

As for a technical reason why encoding takes a long time. The reason is because the process of encoding is VERY mathmatically challenging. Cosines are used quite frewquently in the code and computer processors are not effecient at solving cosines. In fact some times it takes as many as 10 to 20 clock cycles to solve one problem. TMPGEnc has a setting related to this. Its labeled "DC component precision". Lowering this value may save you time, at the expense of quality.

[lizardfish]

Thank you for your quick reply. I have put together some information that may help.

Video source info:

video source type: interlace
source aspect ratio: 1:1 (VGS)
video arrange method: no margin (keep aspect ratio)

frame count: 131419
play length: 1:46
frame rate: 25 f/s
data rate: 132.6 kb/s

Video settings:

stream type: MPEG-2 video
Size: 352x240
aspect ratio: 4:3
frame rate: 29.97 fps
Rate control mode: constant
bitrate: 1150 kbits/sec
profile level: MP & ML (not multi-pass VBR)
encode mode: interlace
motion search precision: normal

Noise reduction and Sharpen edge are selected under advanced options. When I unchecked these 2 options the time dropped to 2 hours. Huge difference.

I'm sure my PC isn't the issue. It's a clone I build myself just recentl with a 2.4 CPU and 1 GIG of ram. Its a gaming machine so graphics aren't an issue ither. I'm sure is a combination of the source file and the program setting I have set.

As far as what I consider normal I'm not sure. I guess 2 hours seems normal for say a 2 hour movie?

Any suggestions? Are there setting I have selected that are maybe not necessary or perhaps not needed. My end result is to have a DVD that I can play in my home DVD player that has at least decient quality. I also understand that garbage in=garbage out so the end result will onlt be as good as the origional source.

Thanks for your help.

[Solarjetman]

If you are getting real time encodes (2 hours for a 2 hour movie), you really can't get much better than that. In fact, in my opinion anything less than a 3:1 encode (6 hours for 2 hour movie) is nothing you can complain about with the computer you have.

[theDruid]

lizardfish - you might want to update your profile.

When you ask a question like this, people will look at your Computer Details.

10 hours might be fine on a 1.5gig machine, but too long on a 2.4gig.

The above is only an example - as we've all now said, TMPGEnc can take a long time and the time it takes depends on many factors.

You've sort of answered your own question by-the-way:

Noise reduction and Sharpen edge are selected under advanced options. When I unchecked these 2 options the time dropped to 2 hours. Huge difference.

Well - have you tried a sample with these settings on and off?

That would seem like a good way of finding out whether the extra time encoding is going to be worth it to you in terms of the quality of the output.

cheers,
mcdruid.

[bugster]

Noise reduction and Sharpen edge are selected under advanced options. When I unchecked these 2 options the time dropped to 2 hours. Huge difference.

Thanks for your help.

You seem to have answered your own question with this.

Don't use filtere like this unless you are sure that you really need them. If you do need them, investigate faster alternatives such as avisynth and virtualdub for filtering the source, then frameserving to TmpGenc for the encode.

Hope this helps.

[theDruid]

great minds think alike bugster :P

[mkelley]

Or just get a faster encoder.

On my machine encoding is near real time with high quality settings in Main Concept. I understand CCE is equally fast and good. These cost more than TMPGenc (about $150) but are well worth it (like the old saw: Good, Fast, Cheap -- pick any two).

[lizardfish]

Thanks for everyone's replys. They have all been very helpful. I just finished encoding that video file I was asking about. When I turned off those 2 settings it encoded in 2 hours and 30 minutes. I believe the movie is an hour and a half long. Went from 665 MB to 815MB.

Is encoding an avi file to mpg (to create a DVD) similiar to encoding a mp3 to a wav file (to make an audio cd)?

[RabidDog]

Is encoding an avi file to mpg (to create a DVD) similiar to encoding a mp3 to a wav file (to make an audio cd)?

I would say yes, but inflating a 352x288 avi file to full dvd resolution 720x576 isnt gonna look good on any telly, you cant put back the information you have taken out. Wavs tho are fully uncompressed unlike mpeg2 which is still compressed video, altho in a different format.
tmpgenc is slow, but good.

[lizardfish]

I'm also using TMPGEncDVDAuthor to create my DVDs. My only options for this program to create DVDs for resolution are:

352x240
352x480
704x480
720x480

I have been using 352x240 to encode all of my mpgs. Should I set the res to the 720x480 setting when encoding for better quality? The higher the res the larger the file right?

But what your saying RabiDog is that a video clip at 352x288 will only encode to the maximum limitations of that file no matter what setting i'm using I will not be able to increase the quality. Garbage in=garbage out right?

Lets say I have a mix of avi's with a resolution of 352x288, 480x352, and others even higher, which of the 4 resolutions should I be using as a standard? Is it in correct to use the 352x240 with files that have a much higher resolution? I'm just not sure if I'm using the best resolution setting. This is all very new to me and I have picked up a lot over the past week. I appolozie if my questions are too obscure.

I have burned a DVD with other mpgs at the lower setting and the results were fine. Not DVD perfect, but al least better than a VHS recording.

Thanks for everyone's help.

[bugster]

I'm also using TMPGEncDVDAuthor to create my DVDs. My only options for this program to create DVDs for resolution are:

352x240
352x480
704x480
720x480

Those are the valid NTSC resolutions for DVD

The higher the res the larger the file right?

Wrong. Filesize is determined only by bitrate and playing time. Increasing the res would need a similiar increas in bitrate to get the same quality (all other things being equal of course )

Garbage in=garbage out right?

Exactly


As to what resolution to use when your source files vary quite a bit. It is in theory possible to author a DVD with files of different resolutions, but I believe this requires a different title set for each res. I am not sure which authoring apps can do this. Perhaps a good compropmise would be to use 1/2 D1 res for all encodes (this is the 352 * 480). This way the lower res sources won't look too bad and although the higher res sources may lose a little quality it should still be pretty good. An average bitrate of 2.5 - 3Mbs will give you over 3 hours on a DVD and still look pretty good at that res.

[lizardfish]

Awsome. Thanks bugster. Greatly appreciated.

I have my bitrate set to 1150 kbits/sec in TMPGEnc. Are you saying I need to incress this setting to get the 2.5 - 3Mbs that will give me over 3 hours on a DVD and still look pretty good at that res.?

I've also noticed that when I encode at 352x480 the preview on the computer using the TMPEnc program looks tall and skinny. Will this work itself out when a DVD is created and played on my TV?

[Solarjetman]

I have my bitrate set to 1150 kbits/sec in TMPGEnc. Are you saying I need to incress this setting to get the 2.5 - 3Mbs that will give me over 3 hours on a DVD and still look pretty good at that res.?

What he is saying is that at 1150kbits/sec, no matter what your resolution, it is going to be just that, a size of 1150kbits per second of film. So a two second clip would be 2300kbits (not counting the audio). Where resolution comes into play is if you increase the resolution and do not increase the bitrate, you will actually get a worse looking picture. That is because the encoder is limited to 1150kbits/sec worth of data, but has a larger picture area to fit into that space. As a general rule, use the resolution closest to your original file.

I've also noticed that when I encode at 352x480 the preview on the computer using the TMPEnc program looks tall and skinny. Will this work itself out when a DVD is created and played on my TV?

That is because pixels on a computer are square, but they are not square on a TV (actually a TV does not even have pixels but you can think of it that way for the theory). It should be fine on the television when you are done.

[lizardfish]

Thanks for the info Solarjetman.