How do you work with mixed quality files?

[Joe Hounschell]

I'm not new to editing video, I'm new to editing video CORRECTLY or as close to correctly as possible when the situations are a bit untraditional. I basically have just been throwing video together in Vegas to put together scenes and such, and then I'd just pick a file type (usually AVI) and render the file. Sometimes it looks great, sometimes I am left scratching my head. I don't wanna do that anymore.

You will see a few threads from me in the near future because I have lots of questions about bitrate and other things that I should break into different posts. My question for this thread is: how do you work with multiple files that you want to put together in a scene, but they are all (or some) different from one another in terms of quality, bitrate, fps, file type, etc.? I just throw them together and carelessly render. But i know there has to be some rules on what you want your settings to be. For example, if you're using HD and SD together. Please help me and point me in the right direction, even if it's just links to articles or something! Thanks in advance.

[Seth Bloombaum]

To answer the general question generally...

I'd first look at what I want to output - is it an HD project? 1080p/i? 720p? SD? SD widescreen?

In most cases, I'd set up the project for whatever is desired for output. Much of my work distributes online at 720p, some at other resolutions.

Then, lucky we're using Vegas, it pretty much performs with mixed formats on the timeline, unlike many NLEs.

On an underpowered machine it can be helpful to match the project settings to the same as the primary media for the project, for better timeline/preview performance.

For final rendering of a master (from which multiple types of files might be created) there are many choices, including uncompressed AVI (huge), DNxHD/MOV, Lagarith/AVI. These are all mastering formats.

For rendering for online distribution it will usually be a high-bitrate h.264/MP4 using the MainConcept encoder. For lower bitrates, Vegas doesn't have the best encoder internally, I'd render a master then create a lower bitrate h.264/MP4 in Handbrake.

There are lots of specific methods and tricks for dealing with this or that situation, so, yes, do post back with any specific questions and someone is sure to jump in!

[Joe Hounschell]

So Vegas will automatically take these mismatched files (an SD 23.9 fps file and an HD 30fps file, just for example since I see these 2 types all the time when looking at the video properties) and adjust as needed? Often in these situations my goal isn't necessarily true HD since I have these SD files in there as well, but more of a "get the highest overall quality possible. The reason I say that is because I would love to keep the HD files as "hd" as possible, but I'm under the (misguided?) assumption that when I mix the SD files in there in the time line, I'm going to get an average of the 2 or make the SD look worse by rendering in a way that keeps the hd looking better. I know you can't increase quality you don't have to begin with, but is there a way to keep the hd without messing up the SD and making it look worse or without making the hd look SD?

Also about bitrate: leaving Internet uploading and streaming out of the equation, what is an ideal bitrate setting and besides streaming online, how does bitrate effect quality (low bitrate vs high bitrate)?

How do I know what is considered low and high?

What happens if you set the bitrate too high?

To give a more specific context to the questions I'm asking, let's assume I'm talking about rendering the final product to a file to be played on a computer or larger flatscreen hd television via a USB drive inserted into a USB slot. The line of questioning I'm asking in this post refers to that scenario. I have a lot of people coming to me with a bunch of shorter clips of various qualities and attributes wanting them placed together in a timeline and rendered into 1 complete "film" or video with the highest possible quality. The problem is, besides my limited knowledge, I get a lot of mp4 files as my source file, and then I'll have some avi files and they will have SD files and hd files and I just don't know how to get the very best milage out of a mix of these attributes for a good final product they can view on their tv via USB drive. Most of them have the mp4 format because that is the only format their device will recognize, which means I have to render the final product back to mp4 a lot of times. I'm just kind of lost.

Oh and when I say "render back to mp4" I don't mean I changed it to begin with. I just mean I start with several mp4 files and avi files and then have to rerender as mp4 for my final output, which probably degrades the quality since I'm rendering mp4 files again as an mp4 file in order to make them all one file after I've trimmed them and put them in the order wanted.

[Seth Bloombaum]

Many of your questions seem to be hypothetical and difficult to answer definitively. It depends!

I'll answer what I can

Originally Posted by Joe Hounschell

So Vegas will automatically take these mismatched files (an SD 23.9 fps file and an HD 30fps file, just for example since I see these 2 types all the time when looking at the video properties) and adjust as needed?

Yes. Until it doesn't. See how it works for you. Cameras and formats vary widely, but Vegas does the best job of being a swiss army knife for all of them; but you can trip it up, depending. Then it's time to look at an offending clip, try to figure out what it is (the freeware version of MediaInfo is incredibly useful here), and transcode it to something Vegas does work with.

...I'm under the (misguided?) assumption that when I mix the SD files in there in the time line, I'm going to get an average of the 2 or make the SD look worse by rendering in a way that keeps the hd looking better. I know you can't increase quality you don't have to begin with, but is there a way to keep the hd without messing up the SD and making it look worse or without making the hd look SD?

Rendering a combination of HD and SD to HD doesn't average the two. It doesn't degrade the HD, except in cases where you're doing something like rendering 1080i/p to 720p. However, yes, blowing up SD to HD can and usually does show artifacts. The big deal here is making the best decision for a project. That's why it's important to be looking at "Best-Full" with your desired projects settings for output in evaluating SD footage. Not all SD is created equal, there's tremendous quality variation, so, IT DEPENDS on what you find to be acceptable quality.

Tip: When rescaling in a project (expanding or shrinking video) it really helps to select "Best" rendering quality in the custom render settings.

Also about bitrate: leaving Internet uploading and streaming out of the equation, what is an ideal bitrate setting and besides streaming online, how does bitrate effect quality (low bitrate vs high bitrate)?

How do I know what is considered low and high?

What happens if you set the bitrate too high?

Bitrate is typically only a concern in Internet uploading and streaming. There is no specific low and high, IT DEPENDS on the pixel dimensions, amount of noise, and amount of movement in your clip.

For something like "normal" 720p (no noise, well lit, static camera, talking heads), low might be 1200Kb/s up to 3Mbps (for direct streaming), high maybe 6Mb/s and up to maybe 10 (for upload). But what is "normal"? It depends. What's acceptable to you and your audiences? It depends.

There are some more objective measures of bitrate, but it depends... you have to get down to bits per pixel per frame, and the need to employ such math to validate quality is rare, mostly if it looks good it is good.

...To give a more specific context to the questions I'm asking, let's assume I'm talking about rendering the final product to a file to be played on a computer or larger flatscreen hd television via a USB drive inserted into a USB slot. The line of questioning I'm asking in this post refers to that scenario. I have a lot of people coming to me with a bunch of shorter clips of various qualities and attributes wanting them placed together in a timeline and rendered into 1 complete "film" or video with the highest possible quality. The problem is, besides my limited knowledge, I get a lot of mp4 files as my source file, and then I'll have some avi files and they will have SD files and hd files and I just don't know how to get the very best milage out of a mix of these attributes for a good final product they can view on their tv via USB drive. Most of them have the mp4 format because that is the only format their device will recognize, which means I have to render the final product back to mp4 a lot of times. I'm just kind of lost.

If you're not in control of the footage you're working with and some is badly shot and/or highly compressed in the camera or afterwards, you have two hands tied behind your back in pursuing quality. Get used to it, and get your viewers used to it. Sorry.

The general rule is that highly compressed source material should be avoided when quality of the finished product is a concern. But it depends; because what I consider to be unacceptable might be perfectly OK in your environment, or vice versa. And how bad is "highly compressed source material" anyways? It depends.

Oh and when I say "render back to mp4" I don't mean I changed it to begin with. I just mean I start with several mp4 files and avi files and then have to rerender as mp4 for my final output, which probably degrades the quality since I'm rendering mp4 files again as an mp4 file in order to make them all one file after I've trimmed them and put them in the order wanted.

You gotta' do what you gotta' do!

Good monitoring is important. If you're looking at a 13" laptop, but your viewers are on a 60" display you're not really making informed decisions about quality.

In general, a high bitrate h.264/MP4 of 6-20Mb/s is going to be fine for computer playback on recent computers/graphic cards. Don't know much about TVs with USB slots for direct playback... but I'd guess such a file works there too.

[Chris Barcellos]

First, I would convert the files to a single format, like Cineform, selecting the output frame rate desired. The files coming out of most cameras is not intended to extensive manipulation. The trancoded file will be more amenable to manipulation, though you should not ever expect it to improve the footage. quality. Cineform is now available from GoPro, as I understand it, Their Studio app is one way to convert, but on a lot of formats, I have had to use HD link, which is a stand alone converter.

From there, output final edit is mastered to the same Cineform format, and then rendered for whatever output required from that master.

[Joe Hounschell]

Thank you guys sincerely for the time you've put into your replies. I'm sorry for what is probably a frustrating group of questions. It turns out, from reading your replies, I know less than I thought I did, and at the same time it sounds like I'm trying to make things more complicated than they need to be. I will take the guidance you've given me and start practicing since experience seems to be the best way to learn variables and I'll start reading articles to get myself a little more knowledgeable. I'll have more questions in future threads, but hopefully you'll notice that they are a little more focused and direct by then. Thank you all!