Re: [Encode2mpeg-users] encoding for the Philips DVP642

[Adam M. <ha...@gm...>]

I did quite a few tests, so I thought I'd share some of my results. First,
the bad news, I wasn't able to solve the choppy video and audio sync issues=
.

encode2mpeg -o 312bframes in.avi -avionly -encode 3:1:2 -ffourcc DIVX
-setaspect 6 -turbo 1 -bframes 2

312bframes.avi turned out to be 1553.4 kbps, 689.7 MB, and took 2h17m44s to
encode. For some reason, this file wouldn't play on my Philips DVP642
standalone DVD player.

encode2mpeg -o 332 in.avi -avionly -encode 3:3:2 -ffourcc DIVX -setaspect 6
-turbo 1

332.avi turned out to be 1285.3 kbps, 581.8 MB, and took 4h5m49s to encode.
The quality was great but playback slowed during complex scenes and the
audio still fell out of sync (after 10min or so of playback).

encode2mpeg -o 742 in.avi -avionly -encode 7:4:2 -ffourcc DIVX -turbo 1
-setaspect 6

742.avi turned out to be 2367.7 kbps, 1.1G, and took 5h3m11s to encode.
Quality seemed better than 332.avi, but the same problems existed (choppy
playback and audio that fell out of sync).

I doubt this is a problem with encode2mpeg, I'm sure the DVP642 is just
picky about what will play well.

Since I have a few other videos encoded with Nandub and VirtualDub that see=
m
to play well, I'm now going to try to create videos exactly like those with
encode2mpeg and see if they'll play well on the DVP642.

Here is some select information from mplayer playback of a video
that *does not* play well on the Philips DVP642.

--- video I made (choppy playback, audio falls out of sync) --
VIDEO: [DIVX] 640x480 24bpp 24.000 fps 1285.3 kbps
Software: MEncoder 1.0pre7-4.0.0
AUDIO: 48000 Hz, 2 ch, s16le, 40.0 kbit/2.60% (ratio: 5000->192000)
Selected audio codec: [mp3] afm:mp3lib (mp3lib MPEG layer-2, layer-3)

Here is some select information from mplayer playback of a few videos
that *do* play well on the Philips DVP642.

--- sample video that plays well on the DVP642 ---
VIDEO: [XVID] 576x304 12bpp 23.976 fps 733.8 kbps (89.6 kbyte/s)
Software: Nandub v1.0rc2
AUDIO: 48000 Hz, 2 ch, s16le, 448.0 kbit/29.17% (ratio: 56000->192000)
Selected audio codec: [a52] afm:liba52 (AC3-liba52)

--- another sample video that plays well on the DVP642 ---
VIDEO: [XVID] 608x256 12bpp 23.976 fps 828.8 kbps (101.2 kbyte/s)
Software: VirtualDubMod 1.5.10.1 <http://1.5.10.1> (build 2439/release)
AUDIO: 48000 Hz, 2 ch, s16le, 128.0 kbit/8.33% (ratio: 16000->192000)
Selected audio codec: [mp3] afm:mp3lib (mp3lib MPEG layer-2, layer-3)

* The videos that play well are all 12bpp, but mine is 24bpp. Maybe this
makes a difference. Is there a way to reduce the color depth of encoded
video to 12bpp with encode2mpeg?

* The videos that play well have smaller dimensions than the one I made.
Might that make a difference, too? I could try reducing the size.


On 10/24/05, Giacomo Comes <enc...@us...> wrote:
[...]

> > (1) when there is a lot of movement, the
> > video gets choppy, and (2) the audio gradually slows down compared to
> the
> > video. Any ideas of options I might add to make this video a bit more
> > playable on this particular standalone player? The spec sheet mentions
> that
> > GMC and Q-Pel are not supported, but I don't think mencoder enables
> these by
> > default, so this shouldn't be a problem. Video encoded with
> > Nandub/VirtualDubMod (Windows) seems to play perfectly.
>
> For problem (2) you should add the option -fixasync. Please try it
> and tell me if this elimitane the the a/v desync when you play it
> with your player.
> For problem (1) the solution should be to reduce the video bitrate.
> During fast motion scenes, the encoder need to use a higher bit rate
> in order to preserve the quality. This is not a problem with a software
> player where the data transfer rate from the harddisk or DVD drive is big=
.
>
> But a hardware DVD player is more limited and the peak data rate can be a
> problem.
> You have different options in order to reduce the bit rate:
> 1) Add bframes. Use the options -bframes 2
> or
> 2) Use a better compression option: -encode 3:3:2 (with this option
> bframes are used automatically, add -bframes 0 to turn them off).
> or
> 3) Decrease the video bit rate: use -usesbr or -vbitrate
>
> You can try to find the maximum data transfer rate of your player.
> Do diffenrent encoding with different argument values of -vbitrate
> and check the high motion scene. Do a binary search until you find
> the maximum video bit rate that do not produce choppy video.
> (in order to be reliable you should also use a cbr audio encoding)
>
[...]

--
Adam Monsen
http://adammonsen.com/blog/