AVC can be compute intensive to decode and if you cannot get smooth playback then you can use proxies or some intermediate format.

Cineform is an intermediate format and will probably decode well on a machine that is having problems with AVC. The files will be quite a bit larger. With this intermediate file you really no longer need the original file for editing. GoPro studio has a free version and it can probably convert your AVC files. Otherwise Vegas can after installing GoPro studio.

You can use the Vegas 12 smart proxy feature. With this when in draft or preview mode the proxy file is used, otherwise the source file is used. It's all automatic. The Vegas smart proxies are XDCAM EX mpeg-2 files, which is the same codec used in "Sony MXF" as people call it.

I have used the smart proxy feature. I also use Vegasaur to get more control over the generation of the smart proxies.

For smart proxy editing in vegas pro 12 go to

http://www.sonycreativesoftware.com/training/vegaspro

At the bottom of the page you will find a video on how to proxy edit using vegas pro 12.

Jerry k

avchd is a snap for the newer i5 and i7 machines, but if you have an older one it can be brutal. If you are doing the odd avchd clip then a proxy or an intermediate is a good idea. But if you plan on doing it regularly then you would be best suited in upgrading the machine

I have problem with rendering mostly. If I apply some video effects such as Magic bullet Looks, it took 6 hrs to render 40 minutes of video. Then if i discover that minor changes have to be made, it is same all over again. I want to explore a way that could accelerate rendering.

That is why I am exploring the possibilities of Intermediates so that if re renders have to be done, it will be a little easy.

RZ

I do all my AVCHD editing on my old Q6600 running WinXP and Vegas 9. It works extremely well, if sometimes a bit slowly. For short projects, say, under 15 minutes, i just grin and bear it, putting up with the longer render times. For longer projects i'll convert to Sony MXF, which then processes probably somewhere around 5 to 20 times faster than AVCHD. However, the transcoding time isn't for the faint of heart and is usually an overnight process, hence why i don't bother on short projects.

Which makes me wonder ... why don't these cameras record to something like MXF to begin with? What's so special about AVCHD that it became the defacto standard for HD camcorders?

Chienworks, I would not pretend to answer your question in such a direct manner and that simply because there is not a single answer. There are a large number of variables that play into the tech and the camera sensor to capture situation.
Note that capture to media -especially of the memory card type - had a lot to do with moving to AVCHD systems.

AND NOW NOTE even further development of even high-end capture systems with 4k sensors will be forced to move away from the traditional MXF (Mpeg2) container.

"Which makes me wonder ... why don't these cameras record to something like MXF to begin with? What's so special about AVCHD that it became the defacto standard for HD camcorders?"

It's a very close cousin to Blu-ray so there is little conversion involved when going to directly to blu-ray (or 'avchd' discs). That makes it pretty consumer friendly.

In actual fact though, it's not really "AVCHD" anymore when it comes off the cam. People are simply calling it "AVCHD" for lack of a better term. ("AVCHD" includes the entire file structure and various helper files)

Using MXF would be very much like the old days with avi.... lots of converting and rendering just to get it to disc every single time.

"Using MXF would be very much like the old days with avi.... lots of converting and rendering just to get it to disc every single time"

The same tends to be true with AVCHD. I use Vegas 9c because it is the last version of Vegas that attempts to smart render AVCHD, but it is not perfect. I have tried other video editors that claim to smart render AVCHD and all had problems. Premiere Pro doesn't smart render AVCHD. Maybe if I live long enough and AVCHD is still around ...

"The same tends to be true with AVCHD. I use Vegas 9c because it is the last version of Vegas that attempts to smart render AVCHD, but it is not perfect. I have tried other video editors that claim to smart render AVCHD and all had problems. Premiere Pro doesn't smart render AVCHD. Maybe if I live long enough and AVCHD is still around ..."

I remember the smart rendering in V9. It worked fine for me until it hit the first edit.

Sony gave up on smart rendering avchd I suspect because there are a few different flavors of it out there and they couldn't meet the needs of all of them reliably. However if you use the supplied software you can do simple cuts/splices without re-encoding. Some of the earlier Sony (consumer) cams were indeed set up with an "easy disc" button which when connected to your machine would do a complete disc bysimply pressing that button

More to the point however, unless you have special editing requirements, avchd can be taken off the cam and placed directly onto disc and played in most blu ray machines.

Again, it's very user friendly (from a consumer aspect) which is why it sticks out the way it does today.

"unless you have special editing requirements, avchd can be taken off the cam and placed directly onto disc and played in most blu ray machines"
___________________________________________________________________
I will be recording to the AVCHD format in the near future. I will edit it, mostly cuts. I plan to color correct/grade with MBL. I plan to store the master file (possibly avi) and then use the master to create delivery formats (mp4). Disk space is no issue. Long rendering times from AVCHD is. I have downloaded the free GoPro (old Cineform). I encoded to AVI files but so far they dont have audio ?? with the clips. trying to figure out.Anyone who is experienced in optimal workflow could chime in. Thanks a lot guys.

RZ

As I posted earlier AVCHD in the camera head development has many reasons to begin with.
However proposals like dragging in camera AVCHD to a Blu-ray disk media are very mis-leading and has gotten the above post by RZ completely off track.

It seems when mis-information prevails- then all bedlam breaks loose. AVCHD tech is a broader issue than Blu-ray creation or workflows.

RZ, goto help file in VegasPro and DVDArchitect for explanations on how to create DVD. Cineform AVI is not going to help you, as you are trying to suggest. You do not need that.

Looks like we went off in a different direction. Let me re formulate the question: if I have AVCHD source files, is there a file format that I can use so that subsequent renders/ encodes to MPEG 2 and 4 are fast.

RZ

"[I]... is there a file format that I can use so that subsequent renders/ encodes to MPEG 2 and 4 are fast.[/I]"

As the issue is re-framed, it is a function of hardware given (at least in the short run) fixed versions of software. I don't think you ever posted your hardware specs. For renders, user hardware always seems to chase codecs and changes in frame size. Now, we are approaching UHD and I'm still running an i7-3770k. I'm getting behind as we speak.

As usual, the answers to your questions have very little to do with your system specs, and we certainly don't need them to provide useful answers.

First, a direct answer to your main question: rendering to an intermediate format such as Cineform or MXF will have virtually no impact on the final render time. This is true regardless of your system specs. Therefore, if your main goal is to reduce that 6+ hour render time, then you will be wasting time rendering to intermediate files. However, there is a big exception to this advice that I will describe in detail at the end of this post.

Second, as usual, there is some confusion between proxy files and intermediates. A proxy file is usually a much lower resolution file that is created in order to dramatically improve preview speed while editing, especially when using older computers. If you have a really slow computer (which even your system specs won't tell us, since CPU clock speed is only one of several variables that determines playback speed), then a proxy is a good idea.

As for intermediate files, this also involves creating a new file from your originals, but at the [i]same resolution[/I] as the original, not lower resolution. This is what you were asking about. As I already noted, this will do absolutely nothing towards reducing your final render times, but it can be a big help in other ways. First, if you have fast hard drives (which your system specs won't tell us because the "system specs" section of your forum profile [i]don't even ask about your hard drive !![/I]) then a Cineform intermediate should produce much faster playback speed than AVCHD 1920x1080 files. However, if you have really slow drives, you may not see as much improvement. Second, Cineform intermediate files let you render some of your more complex effects to second-generation intermediate files without losing any measurable quality. If you were instead to render from AVCHD to a second-generation AVCHD file and put that back on the timeline, you would be able to see significant degradation. If you have small sections of your project which utilize really complex fX or compositing, you can dramatically improve preview speed by rendering to an intermediate and then putting this intermediate on the timeline in place of the originals.

Finally, let me try to actually help you towards your actual goal, which is to be able to make changes without actually having to render the entire project multiple times. The ideal way to do this is if Vegas were capable of incremental rendering where it would sense which portions of the project changed since the last full render, and then only render the changed portions. It would then combine those changed sections with what was already rendered. DVD Architect actually does something very similar to this, and it is a gigantic time-saver.

However, even though Vegas doesn't have this feature (and it would require even more than just "smart rendering" in order to provide it), there is a fairly simple way you can get most of what you want, and do it without having to do much work. Here's what I would recommend:

First , if you have no problem with the preview speed when using native AVCHD files on your timeline, don't bother to create Cineform intermediate files.

Next, edit your project and when you are ready to do your first full render, make that render to Cineform, making sure to set the Cineform properties to exactly the same resolution, frame rate, and interlace settings as your original. That render will still take 6+ hours. Howeve -- and this is the key idea -- if you then need to make a change, put that Cineform file on a new track at the top of your timelines. Then, wherever you need to make a change, split the Cineform file at the beginning and end of the change and remove that portion of the Cineform file. This will let the original tracks "show through" and you can make your changes to those original tracks. Then, when you make your next render, pick a new Cineform file name, using the same Cineform settings, and render to that second Cineform file. Vegas will "smart render" all the video from the Cineform files that remain on that top timeline in your revised project. The rendering of these unchanged Cineform files will take no more time than it takes to copy the un-changed portions of the original Cineform file. Since the "render" of these portions is no more than a file copy operation, you can further speed this smart render if you render to a physical drive that is different than the drive which holds your original files and the first Cineform file.

You can then repeat this process for each subsequent render, deleting the last Cineform file from the top track, and instead substituting the most recently rendered Cineform file on that top track.

Using this workflow, if you only have changes to 1-2% of the entire timeline, the subsequent renders should take only a few minutes.

When you have the project the way you want, you can then render to whatever final format you are going to use for delivery.

And as always, it has very much todo with your system spec; rendering AVCHD on a Celeron CPU will take very long.

johnmeyer makes excellent points about optimizing process throughput regardless of the limits of the hardware and software.

Dear Johnmeyer

Thanks a lot for a very detailed response. I have no problem with preview. Your response is exactly what I need to get my workflow streamlined. Again many thanks to all of you who have enriched me by your input through the years. Best regards,

RZ

[I]And as always, it has very much todo with your system spec; rendering AVCHD on a Celeron CPU will take very long.[/I]Rendering to AVCHD, that is definitely true. Rendering from AVCHD to something like Cineform, not so much. The OP didn't actually specify what format he was rendering to, and said that the problem he was trying to solve was avoiding having to re-do the entire render. This is a problem for everyone, even those of us with fast multi-core CPUs, and advanced video cards with proper GPU support.

It applies to both rendering to and from AVCHD especially if the user doesn't have a GPU that fully supports GPU acceleration, which we don't know, and uses CPU only for processing. Even a codec like Cineform is GPU accelerated on my system with a GPU load from 30-70%. Hardware plays an essential role in NLE performance.
As for your suggested method, which is a good idea but only works for simpler projects. If you have many tracks or transitions rather then straight cuts it becomes very difficult and in my opinion "messy". Try to use your technic on a project like the SCS Benchmark project.
I don't have Magic Bullet, I only use the plug-ins provided by Vegas as they are more then adequate for almost any project, but it might well be the culprit for the rather long rendering times or it may just simply be a hardware limitation...we just don't know for sure. Besides all that, wouldn't it be great to help the OP with a new workflow and optimizing his hardware?

[I]It applies to both rendering to and from AVCHD especially if the user doesn't have a GPU that fully supports GPU acceleration, which we don't know, and uses CPU only for processing.[/I]I really don't think that is correct.

Pretty much all video encoding is [I]asymmetric[/I] meaning that it takes far more CPU horsepower, and far more time to encode it than it does to decode it. This is especially true of long-GOP video formats and, among these, it is most true of H.264 which is at the heart of AVCHD. This is stated nicely in this article H.264 Facts and Fiction Article which states: "[I]the H.264 standard is asymmetrical: all of its computational complexity is on the encoder side while the H.264 decoder is similar in complexity to a JPEG decoder.[/I]"

Any computer built in the past fifteen years can decode JPEG in no time flat.

What this means is that when doing a simple encode from AVCHD, and when that encode involves no rendering (i.e., it is a cuts-only edit with no compositing or fX) it takes virtually no CPU effort or any appreciable time to decode the AVCHD on the timeline (heck, it can play in real time on my 10-year-old 2.8 GHz single core Pentium 4). However, to encode to AVCHD is horrendously CPU intensive compared to something like MJPEG or HuffYUV, both of which compress each frame independently and don't require simultaneous backward and forward references to other frames.

So, when you have AVCHD on the timeline and you are encoding using a simple codec like the two I mentioned, you don't need GPU or a fast CPU to get a reasonably fast render. On the other hand, if you want to render to AVCHD, all those things you mentioned are going to be needed unless you want to spend days waiting for the job to finish.

it takes virtually no CPU effort or any appreciable time to decode the AVCHD on the timeline (heck, it can play in real time on my 10-year-old 2.8 GHz single core Pentium 4).

...and I have AVC files that Vegas plays back at 10fps on my Haswell 4770K. Specifically GoPro 1080p60 30Mbps files. Therefore I would disagree with "virtually no CPU effort" to decode.

Vegas 12 should do better on those, but that is another thread on this forum.

[I]...and I have AVC files that Vegas plays back at 10fps on my Haswell 4770K. Specifically GoPro 1080p60 30Mbps files. Therefore I would disagree with "virtually no CPU effort" to decode.

Vegas 12 should do better on those, but that is another thread on this forum.[/I]Yeah, I read that thread and the problem is definitely a Vegas 12 bug and not any indication of what it takes to decode AVCHD (although see my note below). I had a chance to borrow a GoPro Hero 3 Black a few weeks back and since I was evaluating it, I took video in all the various modes. I put the clips in Vegas 10, running on Windows XP 32-bit (i.e., not the fastest playback platform) and it played smoothly at 30 or 60 fps, depending on which of the various modes I was shooting.

I read that other thread, and it sounded like those who didn't use Vegas 12 were not having a problem. Hopefully Vegas 13 will fix the problem.

Note: 1920x1080 60p video is right on the edge of what computers can handle smoothly, regardless of the codec used. I've been shooting in that mode with my Sony CX-700 for the past two years and often wished that I could get the Vegas GPU support to work for playback on my computer (if you look at my system specs, you'll see that my video card isn't supported very well). :)