Convert AVCHD

[Tazlord]

I think this thread has officially been hijacked...

To the O.P.
If you want to edit in SD DVD quality without having to first transcode your video source, I would suggesting using AviSynth and VirtualDub to do the trick. It will not require tons of CPU power and you can see the final result in real-time. Only when you are satisfied with the result do you have to start the transcoding, which you can you do overnight while you sleep.

Add a little more detail for your suggested workflow. The OP has an AVCHD (1440x1080i h.264) camera master file. How do you suggest he edit that in Virtualdub+AVISynth without transcode?

I'm currently in the process of creating a guide that illustrates how to convert most HD sources to DVD-compliant SD. That being said, I'd like to reduce the chances of doubling my work here. But, I will show you an example Avisynth script that can be loaded into any video editing application that supports AVS input (like VirtualDub).

You will need the following tools installed before you begin.
- ffdshow
- Avisynth

Below is a template script that you can customize to match your system/software. Its basic function is to pull in the media source, convert it to YV12 (DVD color space), and resize it to NTSC).

video=DirectShowSource("drive:\path\to\mediaFile.ext", audio=true).ConvertToYV12()
Lanczos4Resize(video, 720, 480)

mediaFile.ext = Your source file. In this case the OP's MPEG transport stream (.mts file)

The resulting .avs file can be loaded into your video editing application. You can also test the script by loading it into Media Player Classic.

*NOTE*
The above script loads both video and audio from your source into Avisynth. However, only 2-channel audio is supported under this method. If your source contains more than 2 channels of audio, you might want to look into using a multi-channel audio plugin, like NicAudio, for Avisynth.
Also, I noticed the OP's source is 1080i. Since I only have 1080p sources to test with, the method above does not perform any deinterlace. In this scenario I am unable to verify if deinterlace is better performed in the AVS or in the final encoding. If your goal is to create a progressive image, I would recommend looking into the pros/cons of both methods as they apply to your setup.

I hope this offers at least a little bit of help...

[aleph99]

I bought a Canon Vixia HD21 recently and fell in the trap some of you mention above. My PC stutters when I try to play back the MTS files and editing is out of question. So I made the second mistake: somebody told me a Mac would solve the problem and I bought a Macbook. It got worse: the Mac won't even recognize the format. After going back & forth for several days, this is what I have found out:

1. The Mac, for the moment, is not an option. A few third-party players will handle AVHCD, but using all the system's resources and stuttering constantly. Final Cut will import MTS files, but only directly from the camera (you must have the whole directory structure in place and the storage must be external) and converting them to a much larger intermediate format in the process. No way.

2. As to the PC, I made an astonishing discovery: while most third-party players consume 100% of processing power to playback MTS files, Windows 7's own Media Player can handle them with ease using around 10% of processor capacity (this is a 5-year-old dual-core PC we are talking about). At first I thought there was some trick, but by comparing frames from different players I realized that it is indeed playing back the file at full quality. Apparently the player is natively compatible with MTS/AVHCD and that makes all the difference.

3. Which leads me to think that perhaps the problem is not in the hardware, but in the proper implementation of software. If so, soon other players and editors will probably catch up and offer similar performance, allowing us poor sods to finally edit AVCHD natively without having to buy a super-machine. For the moment, the only way I see to edit AVHCD without an intermediate conversion is to use Vegas Pro; it is a slow and painstaking process, but at least it works. I was told Edius can do a better job, but haven't tried yet. Has anybody tried it?

[khblue]

Hope it's ok to wake up this old thread. I'm realising how many layers there are to this issue.

I've (perhaps mistakenly) bought an HD camera and to compound my problem bought it whilst visiting the states so it's recording at 30fps.
I'm using it for teaching drama and would like to be doing reasonably complex editing using Pinnacle Studio 14.
I end up with maybe 200 clips from a weekend of classes that will need editing.
Given that I have this HD footage it would be nice to get some benefit from it, perhaps by playing final footage via data projector at 1280x768.
My PC will not keep up with editing full HD.

So I'd like to batch convert the files from AVCHD @ 30fps to 768 lines @25fps.
I've tried about 6 conversion programmes the closest being Xilisoft HD video converter. It seems to either produce low quality output or output that Pinnacle wont recobnise.
I've now tried XVID4PSP which maintains a higher quality for PAL DV-AVI than the Xilisoft but I can't figure out how to produce files with 768 lines @ 25fps from it. Also, I can't figure out how to do batch conversion with it.

Am I making sense or barking up the wrong tree completely. Any help would be much appreciated.

[aleph99]

Khblue, having tried everything under the sun to get a fairly comfortable editing environment for my HD clips, I would say that the only manageable solution I've found is to use Sony Vegas under Windows 7 with the VASST GearShift plugin, which simply swaps all clips for low-res versions before editing and them swaps them back for rendering. This is a workable - and, at US$ 50, very cheap - solution even if your final product will be a DVD-quality movie, as in my case, because it allows you to benefit from virtual pan & zoom inside the HD frame without any perceptible quality loss (after all, it has almost seven times more pixels than a DVD frame). As a rule, I generally frame the subject a little wider than I should and then zoom into the frame at my own leisure in the editor. For wide-angle shots (say, of musicians playing in a stage) you can even simulate two cameras placed at the same position by zooming simultaneously into different parts of the HD frame.

I am not so sure about your rendering requirements, but I don't think Vegas would have any problem with that. It offers a very wide choice of rendering options. The beauty of the above method is that even if you don't resort to the sort of trickery I mentioned and simply keep the framing as it is, you won't lose any quality by down-converting the clips before you even begin editing.

[khblue]

Thanks aleph,
Presumably each time you add a clip there is a delay while Vegas produces a low-res version ?

[aleph99]

Depending on the amount of footage and other options, quite a long time. But it's all done automatically, which means you can just click & forget. I've found out that the best way to go about it (if you don't mind the low quality while editing) is to define both width and height of the proxy copies to 1/4 of the original.

[Soopafresh]

@khblue- Have a look at Neoscene. Then use the built in features in Vegas to render to 25fps when saving your final video. BTW, 1280x720 is more standard than 1280x768.