How to render sub videos from one large video

j-v wrote on 9/21/2018, 10:19 AM

What is the extension of the video's you want to split.
Rerendering has always influence on the quality, but when they have a mp4 extension my proposal is to use the free app Mp4Tools to split/join mp4 files without quality loss.

Marco. wrote on 9/21/2018, 10:37 AM

Set a Loop-Region around the segment you want to render and in the render option choose to render the Loop-Region only.

john_dennis wrote on 9/21/2018, 10:50 AM

You don’t have to split the large files.

1) Define your clip in Vegas.

2) Save as a Vegas project.

3. Use the Vegas projects in your new project (nesting).

There will be one render from source to final and you want have more large files to track, just projects.

Eagle Six wrote on 9/21/2018, 12:26 PM

I would cut the main event into the smaller events, then run a script file called "RegionsAtEvents", which will place a region on all the events on your track. Then I would rename each region to describe the event, giving them all a unique name. Then run a script called "Batch Render 5 Magix" which will bring up a window to select the place for the renders, the format and template to render with and a couple other options. The "Batch Render 5 Magix" is a modification of the old "BatchRender-Regions" script that worked in Vegas Pro 13 and previous versions, with the namespace changed so it works in Magix Vegas Pro 14 and later versions. Here is a link by zulqar-cheeema https://drive.google.com/file/d/0B0bNEG_bEepqU2p3YjBOQzNGbW8/view

Red Prince wrote on 9/21/2018, 2:07 PM

I would do what Marco said. Actually, I already do it that way whenever I need to render a subsection of a project. No need to nest anything and no need need to cut the main event or run any scripts. The ability to render just the loop region has been in Vegas ever since I remember.

Eagle Six wrote on 9/21/2018, 2:25 PM

I agree Prince, you don't need nesting, cutting, or scripts. On the other hand, when you have hundreds of small renders to make from large source media, tools like VASST, Vegasaur, and simple scripts may increase productivity by reducing redundant labors. It's all a choice in our preferred workflows.

robert-a wrote on 9/21/2018, 3:03 PM

I started with V-J and picked up Mp4Tools which lead me to OpenShot both pretty easy. I'm looking into Marco's recommendation of Loop-Region. Also trying the john_dennis way (I got 75 hours of videos to play with). I had already started with the Eagle Six method - also downloaded the three items and will look them over. But all in all it looks like the consensus is with Marco; Eagle Six; and Red Prince. Eagle Six - is there a (I love Vagasaur) VASST that you could recommend like - Event Tool , Render Assistant, etc?

Eagle Six wrote on 9/21/2018, 5:27 PM

Hi Robert,

No not really, I've never used any of the VASST tools and only played with Vegasaur a long time ago. Everything I need those tools for I have available in simple scripts, but I think John Rofano may have something in VASST that could fit your work flow.

As a follow up after thinking about what you are doing, if I understand it correctly, I would start by placing a mark at the beginning of the original event and name the region. Then move along until reaching the end of that section then split and mark and name before moving through the next section. Then at the end I would run the BatchRender-Region script, and go on to do something else while the renders were cooking. If I'm correct you need to mark the regions and give them a unique name, and the split (cutting) is just required for the BatchRender-Regions scripts to find the beginning and end to do it's magic. But I understand everyone has there favorite or comfortable workflow to develop.

OldSmoke wrote on 9/21/2018, 6:11 PM

Vegasaur doesn't depend on splits to render the region. It can also add a transition or a lead-in lead-out clip. The only time I had issue with this feature was with XAVC-S footage, it just couldn't find the end of the regions, maybe that has to do with Long GOP formats?

Red Prince wrote on 9/21/2018, 7:38 PM

It's all a choice in our preferred workflows.

Yes, of course. It is just that when someone asks in a forum, I prefer to offer the simplest solution to get them started. Eventually, once they get comfortable with it, they can ask further questions or try other things on their own and develop their own methodology. 😉

robert-a wrote on 9/21/2018, 9:23 PM

Well, I just finished one video with the Marco method. I viewed a couple of clips, looking to do color correction as needed. However I may not be rendering the clips to be the most advantageous for color correction.

Some of my video settings are: Pixel Format 32-bit floating point (full range) like I use for photo restorations; composing Gama of 1.000 (Linear), again what I use for photo restorations (GIMP is my photo restorations software); Full-Resolution Rendering Quality - BEST; Motion Blur Type: Gaussian; Templet: Internet 480-30p 4:3 (640x480, 29.970 fps; and a Pixel Aspect Ration of 1.000 (Square). Rendering one clip at a time does take some time. I can see with a batch program at least you can walk away from it.

Going to try OpenShot v2.4.2 tomorrow for another S-VHS tape (2hrs:39min) to see how that feels. Then look to do a batch setup on the third tape.

At least I'm off the ground and getting something accomplished.

Musicvid wrote on 9/21/2018, 9:32 PM

You are creating problems and spending a lot of time putting your (not quite) 8 bit captures in a 32 bit float project. It doesn't add a thing except skewed gamma

robert-a wrote on 9/21/2018, 10:09 PM

Suggestions ..... and something to point me in the correct direction for these videos and possibly an explanation.

john_dennis wrote on 9/22/2018, 12:21 AM

The stated requirement:

"...render each sub-clip into a short stand alone movie that can be combined later into a coherent movie."

The technical specs of the captured video:

Given the bit rate and lossy nature of the captured video and audio (~ h.264 CRF 26), there is exactly zero chance that I would put that media through two renders to deliver a final video.

I've divided clips into sub-sections and I've nested without dividing. This time I would nest or ...

... wait for it...

... start over with a device that captures at a higher bit rate and that uses PCM audio.

robert-a wrote on 9/22/2018, 7:05 AM

That's not so bad to start over again to do a better job. You know what they say "Perfect practice makes perfect". I was supersized that the Elgato video capture converter everything to H.264, at a resolution of 640x480 (4:3). I only digitized 15 of the 30 videos. I'm using a Panasonic AG-7350 for the play back of each video. I'm monitoring with Sewell Direct Luna BNC to HDMI and send it to a LG monitor. The Luna puts out resolutions of 800x600 to 1920x1080. I use a Geforce GTX 1060. Maybe I can send the Luna to the video card and do the capture that way. The AG-7350 puts out at a television format of NTSC TV system of 525 lines and 60 fields. An S-VHS is over 400 lines - BW and color.

So a new approach would be????

john_dennis wrote on 9/22/2018, 7:33 AM

A device like this would give more flexibility. You could capture the interlaced streams into Vegas Pro. DV capture would allow you to make DVDs of your masterpieces for Grandma or deinterlace using different methods for streaming or USB playback. DV would hold up better to editing.

I used one of these long ago when I did my transfers, but the 300 would likely produce more reliable captures.

robert-a wrote on 9/22/2018, 8:37 AM

I will give it a try.

I know from working with photos that the better job you do in your prep work and scanner settings, the far less time will have to be spent in cleaning up the results.

robert-a wrote on 9/30/2018, 6:32 PM

Well, picked up the ADVC 300. And we will see what happens.

Former user wrote on 10/1/2018, 2:38 PM

@robert-a FWIW I did a similar job last year, (PAL region) I wish I had had something as good as your S-VHS machine, I only have a VHS machine, some of my tapes are SVHS. Anyway this is the methology that I used, and is commonly used, but the John Dennis suggestion, ADVC 300 is probably the best way to go and save as DV files, as I did, but using different hardware.

I captured my vhs tapes using the Vegas capture software.

I had an old JVC mini DV recorder that takes line input.

I purchased a PCI-E firewire card for my PC.

I connected the vhs player OUT to the JVC DV line IN and the JVC Firewire OUT to the Firewire card IN on the PC. Note, leave mini DV without tape, put in play mode, enable line-in in DV menu and in the Vegas capture software, under options/preferences disable/un-check “Enable DV device control “.

The files saved are a fixed standard DV25 .avi. Because of going through the electronics of the Mini DV camcorder the result is superior than the poorer digital capture devices that are available.

robert-a wrote on 10/1/2018, 4:25 PM

I had no idea that a DV camcorder could be utilized in that manner. That's a good thing to know. Putting it in play mode without the tape is not intuitive. I also disabled the "Enable DV device control" - Vagus Pro 15. I do photo restoration. This video stuff is pretty foreign to me. Right now I spend a lot of time reading Glossaries to learn the vernacular of video and the Keyboard Shortcuts for Vagus.

I'm looking for a method of adjusting tonal problems, exposure, color, and color correction. But with frames ripping by at 30 fps, your not going to be using a Histogram on each frame. So I'm looking for something that is photo restoration in high speed.

So far I have found many books on film editing (how to shoot & edit your film), but nothing on digital retouching and restoration. It looks to me that video is going to be a long learning curve.

Like Musicvid comment above - I would call that a drive by shooting. You know you have been shot but you don't know why. It works well when I scan photos because it gives me more to work with. I scan B&W in color with 32 bit float and I have more to work with.I guess not in video - your not scanning something.

Former user wrote on 10/1/2018, 5:19 PM

I can’t take any credit for any of that as I picked it up last year after a hellava lot of googling. Compared to what I had previously captured it was the way to go for me. I redid some of what I had already done because it was just better, i.e. the DV .avi captured video.

Important not to make the job too difficult either, i.e. tonal problems, exposure etc. Try and get a small section, loop region, rendered out that looks good enough, then use those settings on similar larger pieces, use presets of multiple FX (if applicable) of your own making if necessary and reuse accordingly.

Musicvid and others are more knowledgable with regards to this.

robert-a wrote on 10/1/2018, 8:02 PM

Right now I'm looking some video tools like the Vectorscope, Waveform, RGB Parade Monitors, and even a Histogram Monitor. These tool look to be for monitoring and adjusting video pixel characteristics. In time I should get there; eventually.

zdogg wrote on 10/2/2018, 3:38 AM

From Vegas experts John Rofrano and Douglass Spotted Eagle Highly recommended: http://vasstsoftware.com/product/renderassistant/

robert-a wrote on 10/2/2018, 11:18 AM

My understanding of rendering a segment of your timeline is that you are letting the computer calculate the lighting and other data of each frame and putting all the frames tighter as a final video. I would like to edit the data before it is rendered (if I’m using that term correctly for video). When I’m doing photo restoration, I do all the restoration prior to rendering the photo which in essence is the so called final (nothing is ever final) published results.

Take a look at what “ john_dennis wrote on 9/21/2018, 11:50 AM”. I should be looking at segmenting my S-vedios into clips and saving each clip as a mini project. This way I lose no data and nothing is changed. Then assemble selected mini projects into the desired project which would be subject based in chronological order. So I should be looking at naming each clip (category_subject_subject-date_edit-version) and then batch processing all the named clips into mini project for nesting when all of the S-videos have been transformed into mini projects. I estimate about 380 mini projects.

How would you go about naming each clip and then batch processing the clips into mini projects? Each of the 30 S-video is about 2 hrs 39 minutes long. Looking at 70 to 80 hours of mini projects. Each to be edited, adjust tonal problems, exposure, color correction and then assembled into various projects.