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View Full Version : Help/advice with xvid on SHARP home theater


Yanaran
4th August 2006, 22:31
Hey all, I've got a problem playing my self-made divx and xvid files on my Sharp HT-M700H home theater player and hope someone can help me.

I don't know what "chip" it uses, and I've not found anything about in in searches (searching doom9 for "sharp" is kind of futile). I've tested the test clips that where recommended in a thread about buying standalone players (clips with b-vops, n-vops, cmc, divx and xvid) and it could play all except the xvid with cmc+b-vops. My problem is it seems to not like high bitrates at all, nor medium bitrates at high resolution. This is not good for me since what I want to do is encode 1920x1080i HD streams to xvid and put on a dvd-rw. The maximum output resolution of the player is 720x480 for ntsc (I tried higher but it says resolution not supported).

The first thing I tried was a 720x480 q2 xvid encode, with ntsc home theater profile, that ended up 2.5gb with sound. When I put this in the player it stuttered right away from the opening scene, and the bottom ~1/3rd of the frame kept flickering black.
I read that CQ encodes break home theater profile, so I did a divx 2-pass encode with average bitrate 2500 with ntsc home theater profile selected and it got a little better but still the same problem in action scenes and at scenechanges.
Thinking that maybe the 2pass encode still had too many peaks in the bitrate I did a 2500 CBR encode (that ended up as 2200 average bitrate in the end, I forced minimum quant=2) and it still had the flickering in scenechanges and fight scenes.

I then tried AutoGK (xvid), with ESS standalone support plugin selected, 2gb filesize and max width 720. That file actually came out quite playable, with only 2 little flickers in the first 10 minutes I watched, but the resolution came out 704x384 so everything looks terribly short and fat on the TV. Although it's playable it's really not a useful option for me unless there's some way to force the output resolution in AutoGK to 720x480. The only thing that stood out to me with this one was the program turned off b-frames because the first first-pass came out too small.

I just now tried to "copy" everything that AutoGK did and encoded a 704x464 version with 1800 average bitrate in MeGUI. It came out as the worst try yet! :o

I hope someone can help me or point me in the right direction. I realize the post turned into quite a story but I wanted to give as much info as I could. Thanks.

EDIT: I forgot to mention I use divx 6.2.5 pro and the xvid version that comes with autoGK (1.2-127).
All encodes with packed bitstream off, gmc and qpel off, default b-frames settings.
Tested both h263 and MPEG matrix.
No filters used except resizing, in the codec when using divx, avisynth-lanczos when using megui.
All files play perfectly on PC.

BigDid
5th August 2006, 00:41
Hi,

Not knowing the chipset used (besides opening the unit and reading on the chip) is kind of annoying. My first proposal would be to use the settings for the most restricting chipset: the ESS Vibrato. Some infos here: http://forum.doom9.org/showthread.php?p=854923#post854923

This is a base to start and you have already verified it with your AGK encode using the ESS Option. From that you can expand trials to settings less tolerant like width up to 720, VBR audio, customs CQM (matrixes). If working you probably have a MTK 1389 chipset, compatible or more performant.
To get a 720 width with AGK see here: http://forum.doom9.org/showthread.php?p=859518#post859518

You are stating " everything looks terribly short and fat on the TV ". From another post I believe you have a 32' LCD TV so my question will be: terribly short and fat compared to what?
If compared to the original DVD, AGK should look good...

My main point is using a SAP (unless very performant and recent models like the Zensonic) will be restricting at least for bitrate: the ESS or home theatre gives near instant kbp/s of 4854 translated to average should not exceed 1500 kbp/s for the whole movie. If you go above you may stutters even on DVD media. You can check your avi encodes with usual tools to get the average bitrate and use DRFanalyser to get a graphical view.
One last point, some SAP really don't like files over 2gb and my personal experience is to split final files to keep them over time.

Now another solution would be to use a VGA card with DVI or HDMI output, I believe your TV may have one of the two, get maximum quality settings whatever the codec and enjoy HD resolution ... :)

Edit: 1 anti-flaming correction. Best moved in the Hardware players section?

Did

Yanaran
5th August 2006, 12:46
Thank you for the reply BigDid, I'm going to try again with the settings in that thread although the only difference to what I was using was I had Trellis still on.

EDIT update: This encode just finished and it actually plays back well, no flickering in the bottom 1/3rd of the screen. 2000kps 2pass, "everything off" (as in your thread). I encoded it at 704x464 because my TV overscans quite alot anyway, so the reduced resolution might have had a part in it also. I still think this is all very strange because the standalone test-clips played back well with b-vops, n-vops and even gmc on the divx test. :)

You are stating " everything looks terribly short and fat on the TV ". From another post I believe you have a 32' LCD TV so my question will be: terribly short and fat compared to what?
If compared to the original DVD, AGK should look good...
Compared to if I force encoding to 720x480 in megui or virtualdubmod. The movie is 16x9 so if I play the autoGK file with the TV set to 16:9 I get black bars top/bottom. I can use the TVs "16:9 zoom" setting to get it to display correct aspect ratio but it gets noticably blurrier in that mode.

The thing that has me confused is that the autoGK encode is over 2000 average bitrate and plays well (but short and fat;) ) while a virtualdub encode at 2000 bitrate but full resolution flickers so much. I'm going to dig into the autoGK logs and try to see if it's some setting I'm not seeing. As for a DVI cable that would rock surely, but the TV is very far from the computer in my house (TV on first floor, pc on 3rd) so I would have to run back and forward alot!


If this thread should be moved to hardware that's fine, I couldn't decide which forum to post to, divx, xvid, autogk or hardware :)

Yanaran
5th August 2006, 18:13
I have also a followup-question about the home theater profile:

You said it has some 4800 max "near instant" rate, what does that really mean? Is it per-frame bitrate as in a maximum on framesize*framerate?

I'm asking because I'm now trying about my 10th encode in virtualdubmod, and I notice in the xvid status window that it says in the "maximum framesize" 65000 (bytes) for p-frames and 106000 for i-frames. Wouldn't that mean a per-frame bitrate of 65000*8*24/1024=12187kbps which is over 2 times that maximum? I'm probably misunderstanding this whole thing.

Is it possible to make another profile just like the home theater one but with an even lower "max" bitrate, so that I could for example make a 2000kpbs 2pass encode but enforce a 3000kbps maximum?

BigDid
5th August 2006, 18:51
I have also a followup-question about the home theater profile:

You said it has some 4800 max "near instant" rate, what does that really mean? Is it per-frame bitrate as in a maximum on framesize*framerate?

Hi,

I'll try to clarify.
When you open the xvid encoder (programs/xvid/configure encoder) 1st screen, 1st line is profile @level, if unrestrited/more/level the max buffer/bitrate/max bits are greyed; this is why the defaut profile can give stutters cause the more bitrate you declare the more the max bitrate climbs.

Now if you select hometheatre/more level you see max bitrate limited to 4854; this is what I call -near instant- this option will avoid stutters for all SAP specially with the ESS chipset.

You can verify by yourself making 2 (short) encodes same settings and average bitrate at 2000kbp/s or more, 1 with unrestricted the other with home theatre profile and compare in DrfAnalyser, you'll see the difference in peak bitrates, this is what can cause the stutters.

If you can use custom CQM than you can use the Mtk profile also restrited to 4854 kbp/s in AGK or other GUI but, you can also try the MTK 6000 (not in AGK) that gives you up to 7281 (instead of 4854). Be aware that not all MTK SAP accepts the 6000 profile and as you still don't know what chipset your SAP has, use with caution...

If you need more elaborate elements regarding xvid, ask for it,more experienced users can develop.

Regarding your other question, profiles are hard coded but user can set different quality presets, use search in the xvid section.

Did

Blue_MiSfit
6th August 2006, 02:13
build yourself an HTPC with DVI or component video output.

Then you can encode everything in 1080p (assuming you are working with HD sources, otherwise there's no point) and play it back with no problems :)

CRCC
7th August 2006, 16:56
build yourself an HTPC with DVI or component video output.
or hdmi output ^^
XboX + XBMC doesn't have any problems upto 1024x576 its a nice alternative and much cheaper :P if you want somesorta standalone player...