How to enable Packed bitstream

[john111]

I use a standalone dvd player (philips 642) to watch avi files. I can usually view most files with no problems however there are always some files that don't play well (sound o.k. but video is pixelated all over the screen).

So I finally did a bit of research and found out that the common factor for all those files that don't play welll is that they all DO NOT have packed bitstream.

Now there are many guides and tools out there on how to Unpack the bitstream using for example MPEG4 modifier. but I didn't see any tool out there or any guide on how to convert a file from UNPACKED to PACKED.

I would assume that if there are tools out there that unpack the bitstream without reencoding that there should be a way to pack the bitstream the same way. However, if i have to reencode the files, how do I do this with packed bitstream. Is there a way to do this with Mpeg4 modifier, Virtualdub or VirtualdubMod??
any suggestions??

[celtic_druid]

No tools that I can think of. However I seem to recall reading of a project to develope tools for doing that kind of thing.

I doubt it is the lack of packed bitstream that is the problem. DivX I believe never uses packed bitstream with more than 1 consecutive bframe. But then the DivX HT specs specify 1 bframe and therefor packed bitstream. Chances are that as well as not having packed bframes, your files have 2 consecutive.

What quant matrix do the files use?

For ESS players I would suggest sticking entirely to the Home Theatre/Theater profiles.

[john111]

well from what I noticed, packed bitstream was consistenly the factor which determined whether the files would play good in my standalone dvd player or not. In fact, after some further reading, it seems to be the deciding factor in most standalone players. However, most players have the opposite problem that I'm having. My player likes packed bitstreams while most others don't.

Im not sure what quant matrix the files are. But i can tell you that it doesn't matter if it's encoded in Divx or Xvid or even across different bitrates. If it is not packed bitstreams i get the same sort of pixelation problem. I should mention that this pixelation problem is different then the problems that occur when someone encodes a file with a really low bit rate and has a fast action sequence playing.

If there are no tools to pack the bitstream then does anyone know how i can reencode the files (preferably in Xvid using virtualdubmod) WITH packed bitstreams?

[guns1inger]

I know that FFDShow resolves the b-frame decoder lag issue which arises because the encoding did not use a packed bitstream. Perhaps encoding with FFDShow is an option ? I haven't done much Divx/Xvid encoding in a long while, so I can't confirm it for you.

[celtic_druid]

The bframe decoder lag is different. The message that you are thinking of is generated by XviD's VfW decoder which has nothing to do with standalone players.

If you stick with the HT profiles, then you will get packed bitstream.

If you don't know what quant matrix they use, then I fail to see how you can rule it out. Although DivX can only do h.263 and MPEG, neither of which should be a problem. But then your DivX files could actually be XviD files with the fourCC changed.

[guns1inger]

When searching for a solution to the b-frame decoder lag, the page that gave me the answer said it was because the bitstream wasn't packed, and that FFDShow could oversome this. I know that using to open the file through AVS as a directshowsource fixed the issue from a playback perspective.

[celtic_druid]

More to the point it is that VfW can't handle advanced stuff like bframes. That is why packed bitstream was invented. It isn't part of MPEG-4 specs, since MPEG-4 was never intended to go in an avi container.

An MPEG-4 decoder doesn't even need to be able to handle packed bitstream.

Newer versions of XviD's VfW decoder simply produce a black frame. No decoder lag message. With directshow it was never a problem.

[Martis]

Hi,

I had the same problem with unpacked bit streams. However since I use DivX Converter that produces packed bit streams I can watch my DivX AVI files without picture problems on my Thomson DTH8564E. Any setting I used with "SUPER" before didn't work, since it always produced unpacked bit streams.

[KBeee]

As the OP was 4 years ago, hopefully john111 has solved his problem.