vertical sync

I didn’t plan to spend a lot of time on the new camcorder since I didn’t believe I was really an early adopter of the AVCHD technology but have come to think otherwise. As I wrote in my last post, the camera works fine but editing the files has proven much harder than I thought. The simple solution to stitch the m2ts (= mts minus the 2GB size limit) files together with tsMuxeR and TSSplitter, two solutions suggested in various forums, didn’t work all that well. tsMuxerR created a file that is playable with the VMR7 renderer but not with the VMR9 renderer (and thus not with my custom SyncVMR9 renderer for GothPlayer which uses many of the VMR9 components). Playback stutters severely with VMR9. Since the files that I stitch and render with various video editing programs (see below) play fine with VMR9 and thus GothPlayer, my conclusion is that tsMuxeR introduces errors. The joined file created with TSSplitter stopped playing at the first joining point.

So I decided to try some of the commercial video editing tools for Windows (unfortunately there doesn’t even seem to exist an AVCHD codec for Linux, much less a full video editor for that particular format). This is what I found out:

• First I downloaded the Ulead VideoStudio Plus trial version. It is said to provide “full HD DVD authoring, AVCHD support” at the Corel web site. The trial version didn’t even recognize m2ts or mts files as importable objects. After some Googling I learnt that I need a “power pack”. (How many euphemism for a patch are there?). The installation program for the “power pack” said that I don’t have Ulead VideoStudio Plus installed which I had. Having waded through numerous forum pages I learned that the “power pack” can’t be installed with the trial version. I tried to mail to Corel support to tell them about my Dilbertian experience but learned that I need the serial number of the product to do that (which I of course don’t have for the trial version). Needless to say, I at this point dropped Ulead from my short list. I suspect that the Ulead marketing guys don’t talk much with the engineers. Nor with potential customers.
• I did get the PowerDirector7 trial from CyberLink to work. It has a very intuitive user interface and actually generated an AVCHD output. The problem was that even though I chose a 50% higher bitrate for the output than for the ingoing clips, I got serious quality degradation that looks like very heavy compression. All grass for instance gets blurry and “blocky”. I didn’t buy an HD camera to watch blocky grass (see comparison below).
• I couldn’t find any trial version at the Pinnaclesys site at all. As my trust in the technology has diminished substantially during the last few days, I will not buy a video editing tool for AVCHD without trying it out.

My best bet now is unfortunately Sony Vegas Pro 8. “Unfortunately” because it costs around $600 and seems to be a semi-professional software with zillions of functions. I was able to stitch together my files with little or no quality degradation (see comparison below), both with WMV and ADCHD output formats. The produced 50 fields/s interlaced ADCHD looks much more fluid (through the CyberLink decoder) than the 25 frames/s WMV. 24 fps (or 25 fps) is really an arcane standard that is overdue for a revision.

I’m writing this while rendering about 7 minutes of video which is estimated to take a bit over 40 minutes on my fastest Windows computer (AMD Athlon 64 X2 Dual Core 4400+). Maybe it’s time for another hardware upgrade. (It will be a challenge to get that purchase order through the family review process though.).

1:1 excerpt from the original AVCHD file from the camcorder @ 9 Mb/s (file size 17.5 MB).

Rendered with PowerDirector7 @ 10 Mb/s (file size 17.2 MB).

Rendered with PowerDirector7 with Smart Video Rendering Technology (SVRT) option @ 10 Mb/s (file size 17.2 MB).

Rendered with Sony Vegas Pro 8 @ 10 Mb/s (file size 16.2 MB).

I got my new Sony SR11E HD camcorder today. A solid piece of hardware that seems to work very well (with just a few minutes recorded so far). The accompanying software sucks though:

• Every time I pause and restart recording, a new file is created. That would be fine if there was a program to stitch the files together into one consecutive file but there is none.
• The supplied HD player only plays files from the camcorder hard drive or from the DVD drive but not video files that have been imported to the computer’s hard drive. Not an “ingenieurmässig” solution at all if you ask me.
• Files can be played with the Picture Motion Browser (didn’t they get that name backward too?) if the files are “analyzed” first. Analysis works fine on one of my XP machines but not the other one. Unfortunately it doesn’t work on my dedicated media computer where I would need it. Other users have reported similar problems in forums.

Get synchronized!

After some downloading and tweaking with filter merits I got a very smooth playback with my GothPlayer media player. I downloaded the PowerDVD8 trial version which includes a graphics card supported AVCHD video decoder. This video decoder generates a remarkably fluid output of twice the video input frame rate (equaling the input field rate). The only audio decoder that would output sound was ffdshow but it worked fine. This may be due to restrictions with the demo version of PowerDVD.

The processing power of my CPUs / GPUs didn’t seem to quite suffice for the highest quality HD video (16 Mbit/s). I got skipped frames in fast pans. I’ll settle for 9 Mbit/s. It’s hard to tell the difference on my current 720 line TV anyway.

Make sure to uncheck the h264 format when you install ffdshow. Otherwise it will probably kick in as the default AVCHD decoder and it has no hardware acceleration making it too slow for 1080 material on most computers. (We’ll see what happens with my hardware acceleration when the trial period of PowerDVD expires…)

Again the advantage of “exclusive mode” fullscreen in DirectX9 was evident. I got severe tearing with other media players using the VMR9 renderer in fullscreen, which is not exclusive mode. With the GothPlayer’s exclusive mode SyncVMR9 renderer there was no tearing with the AVCHD material. Maybe the tearing issue has been solved in Vista with DirectX10 but it can be rather annoying in XP.

I will probably have to invest another $100 for a video editing software to be able to join the video clips together into something long enough to really bore my visiting relatives.

Links

[1] Graphstudio an open source variety of the GraphEdit tool which is very helpful when experimenting with playback of new video and audio formats.
[2] CyberLink, the company behind PowerDVD.