Lite-on 1107HC1 DVR conversion to Xvid

[champagr]

I am using my DVR to record television programs at LP quality. The programs are recorded to DVD+RW as DVDs with the VOBs at 352x480. The 1107HC1 also plays XVID. I am using VirtualDub-MPEG2 with the Xvid Codec to convert from MPEG2 and AAC audio to Xvid with MP3 audio. The problem is that the resulting Xvid is playing as a double-height image (or half-width) video. The image quality is good, but everything is elongated vertically. I tried using the Virtualdub resize filter to create a 352x240 Xvid file. When played in the 1107HC1 the aspect ratio was fine, but the image quality was very poor.

I'm just good enough to use Virtualdub to get the VOB file information, figure out the encoding of the video and audio, and figure out how to convert to Xvid & MP3, but I'm not good enough to figure out how the 1107HC1 plays 352x480 DVD with proper aspect ratio, but can't display 352x480 Xvid with a correct aspect ratio.

My last resort will be to record programs at SP which will result in 720x480 VOBs. If I convert those to Xvid, I guess the aspect ratio will be OK. I just hate to record at SP. The programs are re-run analog cable broadcast television. The quality isn't that great to begin with.

[FulciLives]

MPEG-4 really only supports 4:3 ratios with square pixels ... at least when it comes to stand alone players such as what you have.

So when you convert 352x480 MPEG-2 into MPEG-4 format you need to change the resolution to a 4:3 ratio with square pixels. You have to remember that the DVD format does not use square pixels etc.

So to get a proper aspect ratio you have to change the resolution from 352x480 to 640x480

You might think that stretching the resolution from 352 to 640 is a "bad" thing but remember that the MPEG-2 file gets "stretched" out from 352x480 to 704x480 when playing it back on a TV and MPEG-2 at 704x480 is the same as MPEG-4 at 640x480

If you don't like how it looks at 640x480 then you can try any 4:3 ratio such as:

608x448
576x432
544x416
512x384
480x352
448x336
416x320
384x288
352x256

All of those resolutions will give you a proper aspect ratio.

For the record you mentioned trying 352x240 ... that is not a correct ratio. You could use 352x256 or 320x240 but not 352x240

- John "FulciLives" Coleman

[FulciLives]

Just to give you an example ...

Here is a snap shot of a MPEG-2 file that is 352x480.



This of course will get stretched out to the proper aspect ratio by the DVD player.

To properly convert this for a proper MPEG-4 XviD aspect ratio you would resize it to 640x480 and this is what you get:



As you can see it looks just fine that way with no real "lack" of resolution. Of course I did "cheat" by using animation (since animation is not as detailed as real life) but I had already done the test pics etc. before I thought of that otherwise had I been thinking I would have used a scene from a live action film.

But trust me ... there is little resolution "loss" by resizing a 352x480 MPEG-2 file to a 640x480 MPEG-4 XviD file.

- John "FulciLives" Coleman

P.S.
The MPEG-2 at 352x480 was originally recorded from analog calbe using a DVD recorder at the SP recording mode. This was at 720x480. I then put the MPG file into TMPGEnc Plus and re-encoded it to 352x480 at a 5000kbps CBR video bitrate. I then loaded the new MPEG-2 file into VirtualDubMod to "snap" the pic.

The 640x480 image was created using the newly created MPEG-2 at 352x480 ... I used an AviSynth script to resize from 352x480 to 640x480 ... I then loaded the AVS script into VirtualDubMod to "snap" the pic.

[celtic_druid]

Non 1:1 PAR's are working fine here on my player (MTK based).

[FulciLives]

Non 1:1 PAR's are working fine here on my player (MTK based).

I wasn't aware that any set top players supported anything other than 1:1 when it comes to MPEG-4

How does the set top know to properly resize it? ... Header info on the MPEG-4 file?

- John "FulciLives" Coleman

[celtic_druid]

The PAR info is stored in the M4V video stream and can be used regardless of container, so yes it works even with avi and the player does read it and resize correctly.

I think people's impression of what players are capable of has been ruined by the sheer number of posts you see about the DVP642.

[FulciLives]

The PAR info is stored in the M4V video stream and can be used regardless of container, so yes it works even with avi and the player does read it and resize correctly.

I think people's impression of what players are capable of has been ruined by the sheer number of posts you see about the DVP642.

LOL on that last part.

I bought that POS (the Philips DVP-642) just for the ability to have MPEG-4 playback and it actually worked OK but only for like 2 months when suddenly the disc drawer wouldn't open ... with a rented DVD in it ... so I had to make it open and broke the damn thing LOL

Anyways I assume that only certain chipsets can deal with the PAR in the video stream. Also how do you set that up correctly? ... using MPEG4Modifier?

- John "FulciLives" Coleman

[celtic_druid]

MPEG4Modifier or simply during encoding. Other chipsets should be able to read PAR info and resize. If they can't, then it is just because no one implimented it.

[FulciLives]

MPEG4Modifier or simply during encoding. Other chipsets should be able to read PAR info and resize. If they can't, then it is just because no one implimented it.

Well I mentioned MPEG4Modifier because a lot of people probably use some sort of automated method of MPEG-4 creation ... such as using something like autoGK ... such programs may not allow setting of the PAR while encoding.

So if you can do it after the fact with MPEG4Modifier then that it is good thing, right?

Although ... now that I think about it ... an automated solution like autoGK probably will only do a 1:1 AR with no other options.

- John "FulciLives" Coleman