Pixelization in DV codec

[Michael Rich]

I exported a sequence formatted in anamorphic 720i to the DV Codec so I could copy it over to my PC to compress into WMV. What I found when trying the video on my PC is that the picture is terribly pixelated for some reason. Is the codec playback downgraded if I do not have quicktime pro for windows or something or is it just that way? The same video looks decent on my G5, but of course it has quicktime pro...

Any ideas?

[Ben De Rydt]

You know about http://www.flip4mac.com/ ? This would save you the hassle of bringing everything over to the PC, not to mention the quality loss of recompressing HD material to the DV codec and then to WMV.

I do not understand anamorphic 720i though. Is it 1280x720 HD material or is it 720x480 straight DV material? In the latter case, there are a couple of possibilties to get the footage on the PC with the least amount of recompression:

a) Print the video to tape and capture it from tape using something like Microsoft Movie maker. This will recompress only the frames which have effects applied to them (on the Mac side) and the movie will be in the right format for your WMV encoder.
b) Export the movie out of FCP by using Export -> Quicktime movie. Tick self contained. This will once again only recompress the frames with effects applied. I guess the problem is that this movie will only play in Quicktime on the PC side, but I think you may be able to convert the movie from Quicktime to AVI by using something like Avisynth. This should be really fast as there is no need to recompress the movie, it's only a change of container formats.

If working with Quicktime proves to be too much of a hassle on the PC, you could try to convert the Quicktime movie on the Mac to a straight DV-stream by using Quicktime Pro -> Export -> DV Stream. This will not recompress your movie. I don't know if anything on the PC side will handle a DV-Stream though.

c) Use Quicktime Pro to export the movie as AVI. Choose the DV-compressor. Sadly, this will recompress your movie.

Another problem you might run into is the lack of a suitable DV-codec on the PC side. Quicktime has one, but I don't think it's usable by anything Microsoft related. The AVID DV codec is free, and I think that you might get the Microsoft DV codec by installing Microsoft Movie Maker, also free. That is , if the Microsoft DV codec isn't already installed.

I think there's no more to say about the Mac side. You might want to hit a PC forum for more answers.

[Michael Rich]

Thank you for the reply.

I did mean 720x480, i meant 480i, so I guess that was a little confusing.

All my footage originates on my Mac (capture, edit, etc.), so my problem is compressing something on the mac that is actually playable on my PC. I thought the quicktime DV codec would be the answer, but the pixelization is just too much.

I've found that the Motion JPEG and PNG work, but they take an eternity to export. I actually tried the DV50 codec, but it was not playable on the PC, just reported that I was missing a component.

As far as export to a dv stream, I tried that, but nothing seemed to be able to read that either.

Funny even the export to AVI's did not work very well, all I could really get to work was the Cinepak, I chose the DV AVI and it would not playback on my PC either, its like they use some custom DV codec the normal one on my PC will not play. Too bad that Huffyuv is not available as an export choice for the AVI export, its nice and lossless.

After much fighting, I just decided to use Quicktime videos on the website, I was able to get the footage to embed in the page and so far the quality using the Sorenson 3 codec is real nice. The H.264 looks better, but take FOREVER to compress and is far more CPU intensive on playback than I care for, the Sorenson 3 seems to be a good balance.

FWIW, I ended up compressing to 384x216 (my footage is anamorphic), Sorenson 3, 336 kbit with audio set to AAC, 44.1 mono, 48 kbits. That generates a files that comes out around 384 kbits, which I believe is a pretty decent size for DSL.

Thanks again,
mike

[Ben De Rydt]

I still don't understand the pixelization issue. How exactly did you produce the Quicktime movie and how did you look at it on the PC?

BTW, http://www.divx-digest.com/software/smartvid.html this may be able to help.

[Michael Rich]

Here are two TIFF captures of the same footage. To get the MOV file, in FCP, I did a File->Export->Using Quicktime Conversion. I then chose the DV/DVCPRO codec, best quality, left the sound uncompressed and told it to export.

The two files are single frame captures of the file playing on my Mac and then one on my PC.

Mac:
http://www.alphax86.com/temp/CaptureMac.tif

PC:
http://www.alphax86.com/temp/CaptureWin.tif

Here is the info from the Windows player:
http://www.alphax86.com/temp/CaptureInfo.jpg

Both are with the very latest Quicktime player.

Is there a better way to export that would fix this?

thanks,
mike

[Boyd Ostroff]

This is kinda basic, but I didn't see it mentioned yet. Have you enabled "high quality playback" in the file? Actually I haven't looked closely yet at QT7, but in earlier versions there was an option for this under movie properties in Quicktime pro. You needed to enable this feature before saving the file to get full quality at playback.

[Michael Rich]

I can't say that I've set any High Quality fields in the quicktime file, do you think that by default if you have quicktime pro, it does that automatically, so that might account for why the MOV plays good on my Mac, but not my PC (since I do not have Quicktime pro on my PC)?


I do also have a followup here, I was able to get the File->Export->Using Quicktime conversion via AVI to work. I told it to use the DV codec and manually set the audio to 48Khz, Stereo, 16-bit and I was able to get it to play back on my PC in full quality detail. The downconverted HC1 footage looks pretty good. Since I got that to work, I only wish there was a HD AVI codec to export with so I could give the WMV HD a try.

I have my PM exporting a DV AVI right now, once it gets done, I will try toggling the High Quality flag, save and retry it to see if it still comes out blocky on the PC.

Thanks,
mike

[Michael Rich]

I found the file I had tested this morning, I thought I'd trashed it, but apparently I had not.

So I went in and toggled the High Quality flag on my Mac since I have Quicktime Pro, then tried it on my PC and now it looks just as good as it did on the Mac!!

Why would they not enable that by default if it has such an effect on the footage playback? For all outputted MOV files, should I go in and turn that flag on? Is there a way to do that from Final Cut?

Thanks a bunch!


mike

[Boyd Ostroff]

Hah! I really didn't think it would be that simple, but glad I mentioned it.

As to why.... guess we'd have to ask Apple about that one! I think it's just a legacy from the days when people had slow machines that pushed Quicktime to its limit in keeping up. I would think the assumption should be the opposite today, but evidently they don't agree.

Yes, you do need to enable this flag on a case-by-case basis to the best of my knowledge. There's a free utility that will do this with drag and drop. I only tried it a few times several years ago, and I seem to recall some bugginess, but give it a try. Here's a link - the program is called "HiQual":

http://www.synthetic-ap.com/downloads/index.html

[Ben De Rydt]

File->Export->Using Quicktime Conversion will always recompress your footage. Always use File->Export->Quicktime movie unless you want to save to a different codec or different file format (AVI).

I forgot about the high quality flag. It was introduced when computers were too slow to play DV material full frame at full speed. Basically it comes down to this: Quicktime will decode and play only a single field (even or odd lines) for each frame unless the high quality flag is set, then it wil decode and show both fields. This means you can't see the effect of any deinterlacing algorithm for DV material unless this flag is set. Funny thing is that some people over at ArsTechnica noticed that DV material plays faster with the high quality flag than without nowadays. The Quicktime DV-codec has been optimized so much that it actually takes more time to scale a single field to the full frame than to decode and display both.

Nevertheless, this flag should only have an effect for display, not for conversion. Conversion should always use all fields. I don't know if all tools adhere to this.

[Boyd Ostroff]

Originally Posted by Ben De Rydt

Nevertheless, this flag should only have an effect for display, not for conversion.

True. Setting the high quality flag only affects how the player interprets the file. It doesn't change the data contained in the file.