Fast Forward Problems

[weaver4]

I have a problem if I go Fast Forward to the middle of a DivX/XviD avi movie and then hit play.

In some cases the movie will resume play in just a few seconds. In other cases the movie can take up to TEN MINUTES before it starts playing. I am playing a movie over a fast network with a remote drive.

I took the same movie and encoded it several different ways. I found that the movie did FF just fine if was made with avi.net, autogk or staxrip. But it would take TEN MINUTES if the movie was made with mencoder. [I made the mencoder movie on Linux using XviD.]

[chris57]

I think it searches for the next keyframe. Maybe some apps arent creating them or the index correctly.

[weaver4]

There appears to be over 3500 key-frames in the movie so that is not it. What other ideas do you have?

Here is the rest of the info from avinaptic.

================================

[ About file ]

Name: MyMovie.xlxeqhwsd.avi
Date: 2/03/2008 20:59:50
Size: 1,919,709,488 bytes (1830.778 MB)

[ Generic infos ]

Play duration: 02:23:27 (8606.889958 s)
Container type: AVI OpenDML indexes multi-chunks (*)
Number of streams: 2
Type of stream nr. 0: video
Type of stream nr. 1: audio
Audio streams: 1
ISFT: MEncoder 2:1.0~rc1-0ubuntu13.1
JUNK: [= MPlayer junk data! =]

[ Relevant data ]

Resolution: 640 x 256
Width: multiple of 32
Height: multiple of 32

[ Video track ]

FourCC: DX50/DX50
Resolution: 640 x 256
Frame aspect ratio: 5:2 = 2.5
Pixel aspect ratio: 1:1 = 1
Display aspect ratio: 5:2 = 2.5
Vprp aspect ratio: 4096:1683 = 2.433749
Framerate: 23.976023 fps
Number of frames: 206359 (125324)
Stream size: 1,767,313,228 bytes
Bitrate: 1642.696245 kbps
Qf: 0.418177
Key frames: 3506 (1; 240; 479; 718; 745; ... 206179)
Null frames: 1 (0)
Min key int: 1
Max key int: 239
Avg key int: 58.858813
Delay: 0 ms

[ Audio track ]

Audio tag: 0x55 (MP3)
Bitrate (container): 128 kbps CBR
Channels (container): 2
Sample rate (container): 48000 Hz
Chunks: 358624
Stream size: 137,711,616 bytes
Preload: 504 ms
Max A/V diff: 523 ms
Type: MPEG-1 Layer III
Chunk-aligned: Yes
Emphasis: none
Mode: joint stereo
Delay: 41.6875 ms

[ About MPEG4 encoding ]

User data: DivX503b1393p
User data: XviD0046
Packed bitstream: Yes
QPel: No
GMC: No
Interlaced: No
Aspect ratio: Square pixels
Quant type: H.263

[ Profile compliancy ]

Profile to check: MTK PAL 6000
Resolution: Ok
Framerate: 23.976023 <> 25
Warning: If you need a more complete report, then click on "DRF analysis"

This report was created by AVInaptic (18-11-2007) on 3 mar 2008, h 17:54:08

[chris57]

Can you narrow it down to see if its just mencoder specific by doing the conversion in windows. If it works fine in windows its linux/mencoder problem if it doesnt then just mencoder. You could then ask the experts on the mencoder forums.

[weaver4]

On windows I used a program called AutoMen to make a new XviD avi. AutoMen is a Gui for Mencoder.

Same problem. I Fast-Forwarded to the 45 minute mark in the movie then hit the play button. The movie halted but it took 6 minutes before playback started.

So it does appear that the problem is related to avi's made by mencoder and it does not matter if the movies encoded in Linux or Windows.

Mencoder popularity is growing, and is an important tool. This problem does not occur on the PCs or on DivX DVD players, or DivX handheld products. So it appears that it is something for PCH to fix, not mencoder.

[chris57]

I'm not saying who should fix it just that now you have narrowed it down to the one app maybe you would get a better educated and quicker reply as to why it happens and what actions are needed to fix it, apart from using a different app.

Always remember that the PH is not a dvix certified player so doesnt have to play back to any standard.

[weaver4]

It does not appear to be a DivX problem, but a avi container indexing problem.

I tried adding the -noodml parameter to mencoder and it significantly improved the performance. But the -noodml parameter can only be used on avi files that art smaller than 2Gig, so it is not a real fix. But, it may help people to determine where the problem is.

[weaver4]

According to a thread in Doom 9 this problem appears to be a problem with "multi-chunk" or "multi-part" indexed .AVI files. Hope it can be fixed in the future.

http://forum.doom9.org/showthread.php?t=135511

In the short term it appears that if you are using mencoder you should keep your avi files shorter than 2 Gig and use the -noodml parameter.

BTW: buzzqw -- the author of AutoMKV and AutoMen; froggy1 -- the Author of XvidEnd and H264Enc (linux world), SeeMoreDigital -- the Doom9 Hardware Guru, all provided input on this problem. That's a pretty good team.