From iMovie to YouTube, a.s.a.p.

Imagine this, if you will. You've put together your iMovie masterpiece and want to share it with friends and family. No problem, fire it through to iDVD and send them a DVD - right? But suppose it's a very short clip, or the friends and relatives in question are more of the 'casual acquaintance' variety? Is it still appropriate to physically send a DVD? This was the quandary I was in (short clips, not casual relatives) - so I decided to make use of YouTube.

Now, we know that YouTube wants the video to be in certain formats so they can convert it to the Flash movie that YouTube viewers see. On top of that YouTube specifically recommends divx or xvid video with MP3 audio to achieve the "best results". If the video or audio is in the wrong format you end up with a movie missing the video or audio (as I discovered on several occasions during this process :P).

The problem is finding a video and audio format which - in order of importance - (a) is compatible with YouTube, (b) is as small as possible to reduce upload time, and (c) encodes reasonably quickly and directly from iMovie without any intermediate apps such as ffmpegX.

After a lot experimentation I have found that H.264 video with AAC audio offers the best combination of encoding speed, file size (and hence upload time), and being available from within iMovie itself. The fact that YouTube accepted H.264 was a surprise to me but given the format's excellent video quality it was definitely a most pleasant one!

Here's what I did and the settings I used:

1. Start with your video clip in iMovie. Highlight the video in the Clips panel so that it is displayed in the large preview window. Click File:Export.

2. You should now see something similar to the image below. Choose 'Expert settings'. Click 'Share'.


3. You are now given a save dialog box similar to the one below. Click on the 'Export' drop-down menu and choose 'Movie to QuickTime Movie'. Click Options.


4. You should now see the Movie Settings panel as shown below. In the video section click 'Settings'.


5. Now we get to choose our video format. Set the 'Compression Type' to H.264 with a frame rate of 15 fps with automatic key frames. I have found that a 'Low' quality setting with 'Best Quality' multi-pass encoding produced video that is perfectly sufficient for YouTube. Click OK. (See that preview? That's why this blog has been kinda quiet recently :P)


6. Back at the Movie Settings panel you already saw in step 4, click the audio 'Settings' button.

7. Now we choose an audio format. Unless your home video has some kind of superb stereo sound (unlikely), we can save some space here by choosing a mono format and reducing the bitrate. Set the format to AAC, choose Mono from the channels drop-down menu, change the 'Rate' (frequency) to 22.050 kHz, and choose a target bit rate of 24 kbps. Click OK.


8. Back at the Movie Settings panel again. Make sure 'Prepare for internet streaming' is deselected.

9. Still at the Movie Settings panel. In the video section click 'Size'. You'll probably need a calculator here. My source video was from a European digital camera, so it is PAL video with frame sizes of 784 x 576 (essentially a 4:3 aspect ratio). YouTube's default video size is 425 pixels wide so we'll aim for that width, which means to preserve our aspect ratio our video should be 312 pixels tall (784/425 = 576/312). Choose 'Custom' dimensions and plug in the frame size you just calculated. I also, hopefully unnecessarily, check the 'Preserve aspect ratio' box using 'Letterbox'. Raincoat and an umbrella, you know? :) Check the 'Deinterlace Source Video' box. Click OK.


10. Back at the Movie Settings panel from step 4 ... hopefully for the last time. Click OK.

11. You should now be back at the save dialog box from step 3. Give your exported movie a name, and click 'save'. iMovie will now show you a progress bar for your export.

On my 2.16GHz Core Duo MacBook Pro a 3 minute iMovie clip takes about 10 minutes to export using this method, and ends up being about 3 megabytes in size. This in turn takes me about 3 minutes to upload to YouTube on my bog-standard 2 megabit ADSL broadband with it's pitiful 256k upload speed. For me that is a quick-enough process to make using YouTube as painless as possible. And it keeps the rellies happy! :D

This post isn't about Twitter

Okay, I lie, it is ... kind of. Mike over at industry watcher TechDirt has an interesting article on the demise of Tello and corresponding rise of Twitter. As is the norm for TechDirt, the article is a densely-packed single head-expanding paragraph with very little 'fluff'.

MacBook Pro battery growing pains

A few days ago I noticed my 9-month-old MacBook Pro seemed to be wobbling slightly while I was typing. Since I use the laptop on my dining table I initially thought I had trapped either a coaster or the power lead underneath. However after a quick investigation I discovered that my battery was bulging out from the bottom of the machine! It might not be that obvious in my blurry photos, but it's the white pouch inside the battery that has expanded and forced the cover upwards.



Given the recent reports of a spectacular MacBook battery failure I decided the prudent course would be to operate the laptop solely on mains power for a while!

Burning DVDs from AirDisk

To put it bluntly, think carefully before you try this. Yes, the AirDisk appears to be a normal network drive. However I just burnt a 4.2GB DVD full of jpegs (each approximately 2 - 3 MB) and it took over 6 hours! Throughout that period my Airport throughput meter (courtesy of the indispensable MenuMeters) fluctuated between 50 and 300KB/s transfer from the AirDisk to my MacBook Pro. I don't know why the AirDisk transferred data so slowly - normally I can achieve around 3MB/s for large files and half that for small ones.