What is the "best" freeware MPEG-2 DVD Spec encoder?

[AlanHK]

I have been damn impressed with the quality I get from HCenc. It does seem to have some bugs though so I will share what I have discovered.

I pointed out the GOP errors in the Doom9 forum where the author, Hank315, seems to hang out. He said he was basically a PAL guy and the pulldown is a recently added feature. However, he said he'll work on the GOP problems. He seems to do an update every few months so keep an eye on it.

I've been using it pretty much exclusively, for both PAL and NTSC, and despite some authoring apps like Muxman complaining, have never had any problems with the resultant discs.

One thing I do wonder about are the quantization matrices. I mostly use "qlb", which I've heard is good for fairly low rates as I generally use for compilation discs, but there are dozens supplied, with no documentation. Would be nice to know what each was optimised for, but reverse-engineering them seems a rather tedious exercise so I've never investigated that.

[dphirschler]

I am curious though how HC deals with the MIN since it doesn't ask for that ... only AVG and MAX. I must admit that when using CCE and before that when using TMPGEnc Plus I tried to not set the MIN below 2000kbps and in this example ... where the AVG was 6500kbps ... I would have set the MIN at 2500kbps.

Why on God's green earth would you want to set the minimum encoding bitrate to anything other than ZERO? You want *less* quality? Do you have some funky nonstandard DVD player that won't accept a low min bitrate? Because a) I've never encountered a player that won't handle it, and b) zero should be handled because it is in the spec as far as I understand.


Darryl

[manono]

One thing I do wonder about are the quantization matrices.

Most of the supplied matrices are old XviD matrices. Most are pretty useless for MPEG-2 encoding. I wouldn't use them anyway. That QLB one isn't all that different from the Standard Matrix, and isn't really a low bitrate matrix. If you want low bitrate, maybe try AVAMAT6, AUTO-Q2, or HC. I use the AUTO-Q2 (aka AVAMAT7) quite a bit for low bitrate extras. About the only problem is a tendency to produce mosquito noise beginning around quant 6.

[FulciLives]

I've been using the "default" matrix ... the "MPEG" one.

I did a re-encode of THE DA VINCI CODE to get it to fit onto a single layer DVD recordable and I had to use a fairly low AVG ... I think 3500kbps ... and it turned out damn fine looking ... but then again it is a rather "dark" movie and supposedly "dark" movies encode better.

Like I said it looked amazingly good but this is the reason why in the past I have "restricted" the MIN bitrate to something like 1000kbps to 2000kbps (give or take) because I found that in the past with TMPGEnc or even CCE that there would be too much "macroblocking" or some kind of MPEG compression artifact(s) in dark areas if the bitrate got to be "too low". However I haven't seen this with HCenc.

Last but not least I am curious what vhelp was on about (i.e., his edited post).

- John "FulciLives" Coleman

[dphirschler]

It is my understanding that anything other than zero for minimum bitrate is simply wasting bits on scenes that do not need them. Furthermore, in wasting those bits there, they are not available for scenes that do need them. And so, you get blocking artifacts. So the lower your minimum bitrate, the better. I've never encountered a situation where a higher minimum bitrate will actually improve the encoded image quality.

If you are noticing blocking in scenes, then it makes more sense to raise your average bitrate (or maybe even max if you feel like reducing your audio bitrate).


Darryl

[FulciLives]

It is my understanding that anything other than zero for minimum bitrate is simply wasting bits on scenes that do not need them. Furthermore, in wasting those bits there, they are not available for scenes that do need them. And so, you get blocking artifacts. So the lower your minimum bitrate, the better. I've never encountered a situation where a higher minimum bitrate will actually improve the encoded image quality.

If you are noticing blocking in scenes, then it makes more sense to raise your average bitrate (or maybe even max if you feel like reducing your audio bitrate).

Darryl

Outside of using HCenc I don't agree with you.

In fact some others have noted how some encoders have "blocky black" if the MIN bitrate is too low.

- John "FulciLives" Coleman

[manono]

Outside of using HCenc I don't agree with you.

I haven't used HC enough to know if it's any better in this regard, but I know from experience that a 0 min bitrate strategy can backfire sometimes when using CCE. My usual min is 500. I was encoding Saving Private Ryan once. There's an extended scene at night around a campfire (I think), and for 5 minutes or so you'd see only individual people's faces lit by the fire, with black all around. Maybe only 25% of the screen or less was lit, and the rest was black. And the faces were horribly blocked up. Checking the VBR Bit Allocation screen, I discovered that the scene was using only my minimum set bitrate. I raised the minimum for that scene to a bit over 1000 and ran another pass, and then it looked normal.

Another example I remember was an extra from the March Of The Penguins DVD. There's a storm and everything is white. A guy in red comes out of the distance, so for a minute or so, until he got a lot closer, there was a small bit of red in the middle of all this white. And that red was completely blocked up.

In principle, I agree that a very low or even 0 minimum bitrate can and should work most of the time. But you had better go over the results pretty carefully to make sure there aren't any of these kinds of scenes that might cause it not to work.

[SatStorm]

I never go lower 2500min for full D1 when I use TMPGenc. Macroblocks on static scenes are the rule if you go below 2000kb/s. CCE needs to be set around 1000.

Ah, just to mention: There is always TMPGenc 0.12a for those searching for freeware mpeg 2 encoders.

[dphirschler]

Hey FulciLives, have you had any issues with filesize in HC? I used to have that problem where you use a bitrate calc to get your filesize close to where you want it and then HC would miss the mark badly.

BTW, good point on the min bitrate. That was something I had never encountered, but sounds completely feasible. But I would still stress that a min bitrate of zero should be your goal. FWIW, I normally use TmpgEnc 2.02.31.119 for mpeg2 encoding.


Darryl

[harley2ride]

I got lucky a year ago and got an ADS Pyro 1394 card that came with Adobe Premiere 6.5 (includes MainConcept encoder), for a total of $29.00 on Ebay. I just checked and none out there that cheap now. I still like using 6.5 once in awhile for projects.

[FulciLives]

Hey FulciLives, have you had any issues with filesize in HC? I used to have that problem where you use a bitrate calc to get your filesize close to where you want it and then HC would miss the mark badly.

It seems to be working as one would expect a 2 pass VBR encode to work i.e., the file size seems to be correct.

I have noticed that I do have to leave a bit more headroom than I am used to since I switched to using the 2.x version of TMPGenc DVD Author but I don't think that is HCenc making the files "too big" because I got the same issue with CCE. Seems TMPGenc DVD Author 2.x needs more overhead than the older 1.5/1.6 versions. I guess the menu design etc. just takes up more room so I have to adjust my bitrate a hint lower than I normally would to account for this.

- John "FulciLives" Coleman