trim MPEG-4 video without re-encoding

[video333]

Hello,

 

I want to simply cut out unnecessary video from my 1 hour MPEG-4 file. How do I simply cut out what I don't want without re-encoding the video and losing quality?

[Nationalsolo]

Hi

 

Provided you can load and run your MPEG4 video in VP without a sound/image synch problem (which I get when using MPEG4) then cutting out a section should be no problem. If your question relates to "How do I cut out a section from my project"......

Simply load your project.G o into Timeline mode.

Move the cursor to the start of section you want to cut out.(Or click the blue band over the sequence line at the point required)

Left Click the button marked "Split" found to the left of the sequence line.

Move the cursor to the end of the section to be removed and repeat the action.

The section to be removed will now be highlighted in blue.

Right click this section and choose "Remove selected clip".

Repeat elswhere in the project wherever you want to remove unwanted sections.

 

If your question relates to not losing quality after you have done the above then.. (and this is simply my opinion..)

Save your edited film back to PC or DVD as an avi file using the VP default settings. It should look OK.

 

I generally save my completed projects back to the PC in avi format using the VP default settings.

My original camera footage format is 720 HD 30fps MPEG4 format. (The camera will produce HD up to 1920 x 1080i 60 fps but in practice I have found that anything larger 720 HD simply won't run correctly on my PC)

 

However MPEG4 seems to have a synch problem when I edit with VP or play it back with other players so I convert all my clips to MPEG2 which work fine.

 

Once edited with VP I save the result back to the PC, as mentioned above as an avi...

 

Preset: HD 720

Format: .avi

Resolution: 1280 x 720-HD720p

 

I use the same settings if I save to DVD.

 

They both play and look OK on the PC monitor and the DVD looks fine on a normal TV. (Haven't got HD TV yet).

 

If I need to re-edit the footage now, I can either reload the project, provided I havn't dumped the original clips, or simply reload the saved avi in which case I now have a single sound track instead of the multiple tracks that I may have created in the original edit. Once re-edited,(eg shorted) I re-save as another avi and it looks just the same (to me) as the original avi did.

 

Hope this helps

 

Nat

[video333]

Hi Nat,

 

Thank you for your very detailed response. From what you are telling me, it seems VP is not the correct tool to edit MPEG-4 video unless you want to make a big AVI file which is 5 to 10 times the size. I am wondering if the poor audio synch after trimming problem is arising because you are not cutting on keyframes? I think other software can cut on keyframes to keep everything synched. Does anyone know of software that will trim MPEG-4 without re-encoding?

 

Hi

 

Provided you can load and run your MPEG4 video in VP without a sound/image synch problem (which I get when using MPEG4) then cutting out a section should be no problem. If your question relates to "How do I cut out a section from my project"......

Simply load your project.G o into Timeline mode.

Move the cursor to the start of section you want to cut out.(Or click the blue band over the sequence line at the point required)

Left Click the button marked "Split" found to the left of the sequence line.

Move the cursor to the end of the section to be removed and repeat the action.

The section to be removed will now be highlighted in blue.

Right click this section and choose "Remove selected clip".

Repeat elswhere in the project wherever you want to remove unwanted sections.

 

If your question relates to not losing quality after you have done the above then.. (and this is simply my opinion..)

Save your edited film back to PC or DVD as an avi file using the VP default settings. It should look OK.

 

I generally save my completed projects back to the PC in avi format using the VP default settings.

My original camera footage format is 720 HD 30fps MPEG4 format. (The camera will produce HD up to 1920 x 1080i 60 fps but in practice I have found that anything larger 720 HD simply won't run correctly on my PC)

 

However MPEG4 seems to have a synch problem when I edit with VP or play it back with other players so I convert all my clips to MPEG2 which work fine.

 

Once edited with VP I save the result back to the PC, as mentioned above as an avi...

 

Preset: HD 720

Format: .avi

Resolution: 1280 x 720-HD720p

 

I use the same settings if I save to DVD.

 

They both play and look OK on the PC monitor and the DVD looks fine on a normal TV. (Haven't got HD TV yet).

 

If I need to re-edit the footage now, I can either reload the project, provided I havn't dumped the original clips, or simply reload the saved avi in which case I now have a single sound track instead of the multiple tracks that I may have created in the original edit. Once re-edited,(eg shorted) I re-save as another avi and it looks just the same (to me) as the original avi did.

 

Hope this helps

 

Nat

[Nationalsolo]

Hi

 

"Thank you for your very detailed response. From what you are telling me, it seems VP is not the correct tool to edit MPEG-4 video...."

 

Not at all,VP will work OK with MPEG4 clips I am sure. All I am saying is that mine don't. When the subject of image lag has been brought up elsewhere, replies seem to infer that it's a PC performance related problem rather than a deficiency in the software. There are plenty of references regarding image/sound synch problems with MPEG4 clips and some seem to be the reverse of what I get.

 

Certainly HD MPEG4, particularly in the bigger format requires a PC with a bit of punch in order to edit it. All I know is that the RAW mpeg4 files from my camera,even 1280 x 720 HD, when played on my PC show considerable image lag over seconds of time whether I play them in VP, realplayer etc. and that if I convert them all to MPEG2 format I can edit them without any problems. In fact the image seems clearer and the sound crisper.

 

Nat