Does H.264 in Flash matter? (hint: um, yeah…)

I was listening to the This Week in Media podcast a few weeks ago, and they were reacting to the news that Flash will be adopting H.264 in a future version. They were of course delighted, and said that this basically means that “H.264 wins”. Flash’s distribution is powerful, so maybe in a codec race, this may be the case, but it’s interesting that this development could really trump QuickTime in the browser, even though QuickTime adopted, evangelized, and popularized H.264 earlier. What does Flash have that QuickTime doesn’t? Must-have apps like YouTube that will convince people to update their Flash installs, along with a better cross-platform story.

There’s also an irony, because I remember a conversation (that I can’t find now) on the QuickTime-Users list from sometime earlier in the year, when a poster basically asserted that “hey, when people get sick of crappy Flash video, they’ll come running to QuickTime,” apparently overlooking the very obvious and easy step of Adobe just licensing H.264 for Flash.

Having said that, I wondered just how big a difference it really makes. I think the key to the crappiness of YouTube is not just the basic Flash Video codec (a variant of the fairly old H.263), but also the very limited bitrate. From a little Googling on the topic, it looks like YouTube video is encoded somewhere between 250 and 300 kbps, 320×240.

But just to make sure I wasn’t talking out my butt, I decided to do an experiment. I took some old camcorder footage of Keagan when he was three, and encoded it as H.263 and H.264, limiting the video bitrate to 300 kbps in both cases. The source is 720×480 DV, so I’m really crunching it down.

So, is there a quality difference? Assuming you’re on Mac or Windows (because I’ve encoded these as QuickTime movies and used the QuickTime OBJECT and EMBED tags), you tell me:

320×240 H.263 movie


320×240 H.264 movie

Play both and you should see a difference. If not, try advancing each to the exact same frame and compare side by side. For example, compare time 13712 in the H.263 to the same time in the H.264. (JavaScript and QuickTime plug-in required; tested on Mac Safari and Firefox)

And remember, that’s setting aside one factor that makes the quality difference even more striking: YouTube blows up the videos by about a third (to 480×360), so each of those blurry pixels gets stretched. Full-screen is even harder on the eyes.

So, does the video codec matter? Of course. I’ve been in such a mindset that bandwidth can compensate for codec differences that it’s really a bit of a wake-up to see just how much of a difference it makes in this little demo.

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