Tag Archives: H.264

QuickTime 7.0.4 and H.264

Buried in the fine print of the latest QuickTime update (7.0.4) is a mention of improved H.264 performance. Having heard some talk on the professional video mailing lists that the latest update can be problematic for Final Cut Pro and Avid users, I opted to use my PowerBook as a testing platform. My test file was a 10 second, 720×486 uncompressed 10-bit QuickTime file. Using QT Pro’s “Export to iPod” option in 7.0.3 , the file took an insanely long 2 minutes 12 seconds to encode to an iPod-friendly .m4v file. After upgrading to QT 7.0.4, the file encoded in 38 seconds, almost 3.5x faster. Not bad. (PowerBook is a 1 GHz G4 with 1 gigabyte of RAM.)

Is it worth upgrading? I’m still hesitant to put QuickTime 7.0.4 on production machines. I’m waiting to hear from trusted sources on Avid-L2 and FCP-L before making the leap.

Compressor 2 video iPod settings

Though I haven’t been able to figure a way to get an H.264 encoded file out of Compressor 2 that will load onto the video capable iPods, I have been able to encode valid MPEG-4 files that work. I’ve found that 512 Kbps works well on the iPod. This setting doesn’t look as crisp as H.264 encoded material, but is passable on the small screen. I don’t consider it acceptable for NTSC display.

Pictured are the settings I use. Don’t forget to resize the material to 320×240 in the format tab (circled).

It’s surprising Apple hasn’t released an update to Compressor 2 to address the H.264 shortcoming. I would expect one shortly.

Speeding up H.264 encoding for iPods

I’ve gotten a lot of mail asking about alternatives to the QuickTime Pro Export to iPod preset for H.264 encoded media that will transfer and play to an iPod. The Apple preset is easy and yields excellent results, but apparently the deinterlacing algorithms are the cause of the excrutiatingly slow encoding process. Also, the 750 kilobits per second data rate makes for some pretty chunky files. My Curb Your Enthusiasm episodes are over 200 megabytes apiece. This is a fine setting for video destined to be played on an NTSC monitor, but it’s overkill if the iPod is the video’s final destination.

Here are my alternative settings. They render three times faster than the Export to iPod preset and take up about a third less disk space. I find the results look good on the iPod.

In the QuickTime Pro Player, select Export -> Movie to MPEG-4.

In the file format selection window make sure to select MP4 instead of the default MP4 (IMSA). That will make the H.264 codec available in the Video Format window. Select the 320×240 QVGA setting for Image Size. I haven’t experimented with the keyframe settings yet. If anyone has, please leave a comment below. I’ve set the data rate to 512 kbits, but if the content is mostly talking heads in a studio or other non-taxing content, then 250 – 350 kbits may be fine.

Next, click the video options button. Restricting the profiles to main and baseline yields a file that will play on first generation iPod. Switching to single pass encoding also speeds improves the render times.

Ars Technica has a tutorial that uses the shareware FFMPEGX utility. I haven’t gotten to create an iPod-friendly video yet, but will report back if I do. In the meantime I’ll continue experimenting with Compressor 2 as well.

Video podcast tutorial

Here’s a quick tutorial for those who want to get a video podcast up in short order. You’ll need is the following:

  • QuickTime Pro 7.0.3 for H.264 encoding, QuickTime Pro 6 for MPEG-4
  • Any text editor
  • An FTP client [ Mac | PC ]
  • Web server space
  • A QuickTime movie you may legally distribute
  • Step 1

    Open the movie with the QuickTime Pro Player and select Export from the File menu. From the Options menu select “Movie to iPod video (320×240). Save the file, making sure not to remove or change the m4v file extension. Be prepared to wait. Apple wants your video to look good, so it defaults to the H.264 codec and encodes using 2-pass VBR. On my PowerBook it was taking something like 3x real time to encode. Once you get the hang of this you can experiment with other encoding methods, but for now this delivers a darn good picture even if it takes forever and uses a bit of bandwidth (750 kbs/sec).

    If you don’t have QT 7, you can use QT 6. Export as an MPEG-4 file with the mP4 extension. You will have to set the raster size and the bit rate manually in Options. The mp4 codec yields a lower quality image at the same bit rate as H.264, but encodes a lot faster.

    QT Pro Export Window
    Step 2

    Create the XML file for iTunes or another RSS reader to access. This document is served like a web page from a standard web server. Rather than go through the steps one by one, I’ve created a template. Just go through the template and replace anything written in all caps. You’ll see what I mean once you’re in there. Make sure you save this file as text-only. I prefer to edit these in Dreamweaver or with BBEdit.

    Step 3

    FTP the files to the web server.

    Step 4

    In iTunes 6, select Podcasts in the left column. Under the Advanced menu, select Subscribe to Podcast. Enter the URL of the XML file you created. Your video will begin downloading in iTunes.

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