Choppy HD preview, even with decent hardware

[Benjamin Ramsey]

I edit a LOT of footage from my Canon Vixia HF20 using Sony Vegas Pro 9.0, and I have come up with a neat trick to avoid the quality hit you take whenever you convert formats or taking up all your hard drive space with a “loss-less” in-between editing format, but still edit with very smooth video preview.

First off, people need to understand that whenever you convert video, and I mean WHENEVER, you lose quality. You damage the video. It’s like the old days with a tape recorder and you make a copy of a copy of a copy – they each sound worse and worse. Converting digital video files to another format will always cause a degradation to the video quality, due to the different ways compression algorithms handle video information such as color, motion, etc. Sometimes it may be minor enough that most people can’t easily tell the difference, and sometimes it will be worse. If you use a relatively loss-less format it will have to be HUGE in file size to avoid degradation, which isn’t very feasible for the average home user’s hard drive space. It’s best to avoid all this as much as possible.

The ideal is to work with your original camcorder’s video files throughout the editing process, and then only when you’re all done, render to your desired output format(s). That way there is only ONE conversion happening, during final rendering.

Of course, editing with less than 1 frame per second choppy video preview is difficult if not impossible, so many people are willing to take a layer of conversion damage if it means they CAN edit. But I found a way to have my cake and eat it too.

Here’s a brief nutshell of what I’m doing:
First make a Sony AVC super-low-res render MP4 file (using a custom “240-30p 384k” setting I made works well). Then use it to do all the editing with smooth video previewing all the while. Then close Vegas, move the small MP4 away, open Vegas – it can’t find the files, you then supply it with replacement files, using the original videos, which now have all the edits in place!

I can even do this in “batch” by loading many clips, then douple clicking each clip and hitting “R” to make a “region”, then in the menu “Tools” – “Scripting” – “Batch Render”, select “Render Regions” at the bottom, select naming convention, select encoding format and let it “cook” overnight.

Here is a longer step-by-step version:
1 – Open Vegas, load the HD “MTS” videos into video track
2 – One at a time, double-click on each video segment and hit “R” to make a “Region” above the track, and repeat for all the videos
3 – In the menus select “Tools” – “Scripting” – “Batch Render”
4 – Select naming convention, select a small encoding format (such as my custom Sony AVC “240-30p 384k”), and select “Render Regions” at the bottom
5 – After all the parts are done rendering, start a new project in Vegas (don’t bother saving the current project)
6 – Load the new small videos into the video track, and save the project with whatever name you want
7 – Edit your movie, using the small videos which should work smoothly and easily all the while, then save your final version.
8 – Close Vegas, and move the small video files away (such as into a separate folder for temporary holding)
9 – Open your saved final version of the project – Vegas will complain about missing files:
10 – Supply Vegas with replacement files, selecting your original HD videos (in the correct order if there are more than one)
11 – Save the final version of the project, perhaps with a new name this time
12 – Render your HD video!

It works beautifully! I avoid doing an extra video conversion, thus retaining the perfect original quality of my camcorder files, but I also am able to edit with perfectly smooth video preview, even during transitions and effects. It’s definitely a “hack” or trick method, but it works well.

Hope that helps.

[Gustavo Rasche]

Benjamin, this should save you a lot of work.

https://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=582248

It is called Proxy Stream, a great script that batch converts your files, and allows you to switch between on the fly. Pretty handy for automating the process.

[Benjamin Ramsey]

Thanks, I appreciate that help. But I must apologize, I should have replied a few weeks ago because I have indeed discovered Proxy Stream which I now LOVE!!! I can’t recommend it highly enough! But perhaps others will find this info now and have the link, so your post will do some good.

Thanks!