stuttering .mp4 cuts

[lovelove]

hi,
I need to cut a .mp4 file, but no matter what I do, the output file stutters.

I tried
(1) Avidemux (http://www.videohelp.com/tools/AviDemux)
(2) I also used mkvmerge (http://www.videohelp.com/tools/MKVtoolnix) to convert to mkv and used its split function.

In both cases I had the same problem: output file stutters.

It's jinxed. The original mp4 file doesn't stutter at all (neither in VLC (http://www.videohelp.com/tools/VLC_media_player) nor in my TV hardware player).
But as soon as I cut it, the output file stutters. WHY?
Any help much appreciated. Thank you!

input file:

General
Complete name : F:\video\comedy\buelentlive.mp4
Format : MPEG-4
Format profile : Base Media
Codec ID : isom
File size : 1.65 GiB
Duration : 1h 29mn
Overall bit rate : 2 620 Kbps
Writing application : Lavf52.63.0

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 1h 29mn
Bit rate mode : Variable
Bit rate : 2 452 Kbps
Width : 720 pixels
Height : 576 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 fps
Standard : PAL
Bits/(Pixel*Frame) : 0.237
Stream size : 1.54 GiB (94%)
Tagged date : UTC 2010-08-21 12:42:09

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format version : Version 4
Format profile : LC
Format settings, SBR : No
Codec ID : 40
Duration : 1h 29mn
Bit rate mode : Variable
Bit rate : 165 Kbps
Channel(s) : 2 channels
Channel positions : L R
Sampling rate : 48.0 KHz
Resolution : 16 bits
Stream size : 106 MiB (6%)
Tagged date : UTC 2010-08-21 12:42:09

[hello_hello]

What's CPU usage like when the video stutters? Does it stutter all the way through? Both/all sections stutter?

If the video is stuttering the first thing I'd look at is CPU usage and from there try to work out why. Maybe it's some odd problem with just one of the streams. What if you remux/cut the file while disabling the audio? If it doesn't stutter try just the audio on it's own.

I don't really have a solution or know why it'd happen but that's at least something to try to see if you can pinpoint the cause. I had a similar problem when playing back a couple of video files containing multi-channel AAC audio and whether it'd stutter seemed to depend on where I started playback. In my case it turned out to be the ffdshow audio decoder's EQ. Disabling it would fix the stuttering problem and CPU usage would return to normal. I never did work out why, but converting the audio to AC3 also fixed it.

Just some thoughts.....

[FlashVideo]

If the DVD is anamorphic 1.85:1 then do the following, if not scroll down.
In MPEG Streamclip:
Load the ripped VOB file.
Select File: Export to MPEG-4
Click the iTunes button in the upper right corner.
Select the iPod 640X360 (16:9) option.
Click OK

Quality: 85%
Frame size: 720X480
Limit Data Rate: 1800 kbps
Sound: No Sound
Frame Rate: 23.976
Better Downscaling: CHECK
Deinterlace Video: CHECK
Click the Preview button. If you see black borders around the picture you can use cropping. If you do crop then select "scale"
Click Make MP4. (This will take a while)

When finished encoding the video you must encode the audio.
Select File: Export Audio
Format: MP4 AAC
Channels: Stereo
Sample Rate: 48 kHz
Bitrate: 128 kbps (DO NOT exceed 160 kbps or it will not work on the iPhone)
Click OK (This will take a much shorter time)

In YAMB
Double click the "Click to create MP4" area.
Click Add and select your video file.
Click Add and select your audio file.
Click on the video file and Click Properties.
Pixel Aspect Ratio: Custom
Enter 32 : 27 and click the green check.
Click OK
Browse to the desired output site.
Click Next
The resulting file will be your finished product.

If the DVD is anamorphic 2.35:1 then do the following.
In MPEG Streamclip:
Load the ripped VOB file.
Select File: Export to MPEG-4
Click the iTunes button in the upper right corner.
Select the iPod 640X360 (16:9) option.
Click OK

Quality: 85%
Frame size: 720X356
Limit Data Rate: 1800 kbps
Sound: No Sound
Frame Rate: 23.976
Better Downscaling: CHECK
Deinterlace Video: CHECK
Use the preview and the cropping tool to remove all the black boarders. Usually about TOP: 40-42 and BOTTOM: 42-48. Just go back and forth to preview until you have cropped all the black areas. Select "scale".
Click Make MP4. (This will take a while)

When finished encoding the video you must encode the audio.
Select File: Export Audio
Format: MP4 AAC
Channels: Stereo
Sample Rate: 48 kHz
Bitrate: 128 kbps (DO NOT exceed 160 kbps or it will not work on the iPhone)
Click OK (This will take a much shorter time)

In YAMB
Double click the "Click to create MP4" area.
Click Add and select your video file.
Click Add and select your audio file.
Click on the video file and Click Properties.
Pixel Aspect Ratio: Custom
Enter 32 : 27 and click the green check.
Click OK
Browse to the desired output site.
Click Next

The resulting file will be your finished product.

[lovelove]

If the DVD is [...] load the ripped VOB file [...]

see:
I need to cut a .mp4 file [...]
The original mp4 file [...]

--------------------------------------------------------

hello hello_hello :-)
thank you for helping

What's CPU usage like when the video stutters? Does it stutter all the way through? Both/all sections stutter? If the video is stuttering the first thing I'd look at is CPU usage and from there try to work out why.
Yes, it stutters all the way through. CPU usage doesn't even reach 50%. Plus the source file (mp4) does NOT stutter at all. It has the same video/audio stream, so it is not a CPU issue at all. Plus, the video is NOT freezing, as would be the case with CPU issues. Instead playback is jerky/stuttering/jittering and looks as if it were rapidly jumping back and forth while advancing.

Maybe it's some odd problem with just one of the streams. then why does the source file play fine?

What if you remux/cut the file while disabling the audio? If it doesn't stutter try just the audio on it's own. I tried. The audio is not affected by the problem, i.e. in the stuttering video the audio is ok, only the video stutters. If I remux without audio, the video is still stuttering.

I had a similar problem when playing back a couple of video files [...] it turned out to be the ffdshow audio decoder's EQ. in my case I think it's not a problem of a faulty playback because both VLC (software player) AND my TV (hardware player) suffer from the same stuttering problem with this file, so I guess the file itself has the problem.

[lovelove]

(stuttering) output file MEDIAINFO:

General
Complete name : F:\video\comedy\buelentlive.mp4
Format : Matroska
File size : 3.72 MiB
Duration : 18s 5ms
Overall bit rate : 1 732 Kbps
Encoded date : UTC 2011-07-01 22:51:27
Writing application : mkvmerge v4.4.0 ('Die Wiederkehr') built on Oct 31 2010 21:52:48
Writing library : libebml v1.0.0 + libmatroska v1.0.0

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Codec ID : V_MPEG4/ISO/AVC
Duration : 18s 0ms
Width : 720 pixels
Height : 576 pixels
Display aspect ratio : 16:9
Frame rate : 25.000 fps
Standard : PAL

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format version : Version 4
Format profile : LC
Format settings, SBR : No
Codec ID : A_AAC
Duration : 18s 5ms
Channel(s) : 2 channels
Channel positions : L R
Sampling rate : 48.0 KHz
Resolution : 16 bits

[hello_hello]

I can't suggest anything other than extracting the raw video and audio streams from the MP4 with YAMB, and to then try muxing the raw streams into an MKV (rather than remux the MP4 directly).
I've not had any problems like yours caused by remuxing but I have had odd audio sync issues which were fixed by working with the raw streams directly. I've no idea why.
If you remux the MP4 into an MKV without cutting does the MKV still stutter?