Create Professional-Grade Slideshows using H.264

Quicktime users have a powerful codec at their disposal (a codec is the software used to compress a finished video) that's as simple to use as clicking a few extra buttons in Photo to Movie. H.264, one of the latest advances in video technology contained in Quicktime, offers clean, crisp, high-quality video that maximizes hard drive space without compromising the beauty of your vision. If you have the latest version of Quicktime 7 installed then follow these easy steps to make the most of your slideshow.

These instructions refer to the Photo to Movie 4.0.8 (Mac OS X). Other versions and Photo to Movie (Windows) will differ slightly.

Create Professional Grade Slideshows using H.264

Create your Slideshow

First, create your slideshow. When you've completed your creative process, then choose the menu item File > Make Movie

Choose your movie format

Next, select the QuickTime button at the top. You'll see a number of options. Under "Movie Format," select "Custom".

Choose your desired frame size

Next, enter the desired frame size in the "Width" and "Height" fields. This indicates how large the final movie will be. When you change the frame size, Photo to Movie automatically constrains proportions for you, so the video will never look stretched or squeezed. Web video is often 320x240, standard video is often 640x480, and high definition video is often 1920x1080.

Select compression type

Now, click on the "Video" button. Select "H.264" from the compression type menu.

Choose your frame rate

Select your frame rate. Frame rate is, simply put, the number of images shown during every second of video. The Standard NTSC (North American) frame rate is 29.97. However, if you'll be showing your slideshow on a non-US TV or are exporting for use in other software such as Final Cut Pro or Flash, there are a number of other options available to meet your needs.

Key frame settings

Select your key frame settings. When video is compressed, a complete version of every frame of the movie is not included in the file. Instead, most frames just record the differences from the previous frame. Key frames are the ones that are complete frames. The more key frames, the higher the video quality, but also the larger the file size. You should choose a keyframe rate that considers the visual style of your movie; lots of movement, cuts, or shifts in color and lighting will require a higher keyframe rate, since the movie will change a good deal from one frame to the next. At 30 frames per second, a good rule of thumb is to use a key frame every 24 frames. (about 0.8 seconds).

Limit the overall data rate

You can also limit the overall data rate of your movie. The H.264 codec compresses data so that the larger details in each frame of the movie are put first and the smaller details are put last. By reducing the data rate, you can essentially strip off the smaller details which ironically take up more space in the rendered file. You can determine your data rate settings according to where your movie will be played. For movies played over a phone, choose 150-200 Kbps; for the internet, choose 300-500 Kbps; for standard video, choose 1000-2000 Kbps, and for full high definition video, choose 7000-8000 Kbps. For the highest quality possible, uncheck the "Limit Data Rate to" checkbox.

Set your compressor quality

Finally, set your compressor quality. Apple recommends, as do we, that all video be exported at the highest quality -- this really shows H.264 in action. However, if you find that your files are getting too large you could slide the the cursor to the left a bit without too much of a downgrade.

Now your settings are calibrated! Don't forget to configure your audio before hitting "Make Movie".

Another note: H.264, like most codecs, is highly valuable but can take some getting used to before you maximize its potential. We recommend exporting a few trial slideshows at different settings just to get you accustomed to how the slightest changes in options can have large effects on your final file. Good luck, and we hope you enjoy the life-like quality of the slideshows that H.264 can produce.

For more information on H.264 and the points discussed above please visit Apple's tutorial here.

http://www.apple.com/quicktime/tutorials/h264.html

Written by Joseph Jon Lanthier, LQ Graphics, Inc.

February 23, 2008 - First version