Peer Review: Wine Library TV
During early episodes, the camera appeared to be leveled below the speakers and looking up, where level to slightly looking down is preferred. That appears to have been fixed. The cameraperson maintains good rule-of-thirds positioning throughout (Figure 5), and though zoom-ins to examine bottle labels are a little quick and jerky, motion is smooth on the whole. Overall, I like that the producers resist Mad Money-ish camera motion and put the subjects and the wine in charge of retaining your attention.
Figure 5. Classic rule-of-thirds positioning
Audio: 5/5
Audio quality and levels are good. While no lavaliere or other microphone is visible, the audio sounds like the producer used an external microphone rather than the camcorder’s internal one. As you can see in SoundBooth, levels are good, and a close-in analysis revealed very little noise (Figure 6).
Figure 6. Audio levels are good, and the audio was free of noise, as shown in this Adobe Soundbooth analysis.
Editing: 4/5
Not much to rate here, since it’s a live, uncut show that begins with a simple, attractive animation and closes with the show’s URL. Titles are large and simple for easy compressibility, and otherwise, minimal editing is performed. The show missed a perfect rating because it doesn’t appear that the editor attempted to boost the brightness of the shadowed regions in the video, missing an opportunity to minimize the effects of the overhead lighting.
Preprocessing: 5/5
Deinterlacing doesn’t appear to be a problem, and the display aspect ratio is correct. Nothing to fault here.
Encoding: 2/5
Wine Library made serious gaffes with both FLV and QuickTime encoding. Let’s start with Flash.
Wine Library produces 640x480 VP6 video at 29.97 fps and a video data rate of 611Kbps. This translates to .088 bits per pixel, about average for broadcasters producing at this approximate resolution. So why are there artifacts in the background and mosquitoes around the subjects, problems that are not evident in most other similarly configured videos?
The first reason is the background, as discussed previously. Second, as shown in Semaphore in Figure 7, the Wine Library video has a keyframe every second, much more frequent than sites such as ESPN.com, which averages a keyframe every 15 seconds. Since keyframes are the least efficient frame from a compression perspective, unnecessary keyframes degrade quality, which is evident in the Wine Library clips.
Figure 7. A keyframe every second makes it tough to get good quality, even at data rates of 700Kbps for a 640x360 stream.
For the QuickTime stream, Wine Library is encoding 640x360 video at 29.97 fps and a video data rate of about 1.3Mbps, which should be plenty for pristine quality. However, according to MediaInfo (Figure 8), Wine Library is using the MPEG-4 codec, not H.264, which is highly questionable and almost unprecedented. Heck, even YouTube went the H.264 route in its 720p video offering, as did Facebook.
Figure 8. The MPEG-4 codec? I thought that was dead!
I’d hesitate to assign a percentage to the quality differential between the two, but I’ve seen estimates that H.264 delivers the same quality at between 30% and 50% of the bandwidth. This means that by switching to H.264, Wine Library could drop its data rate by 400Kbps—500Kbps with no quality degradation. Given that every current encoding tool now supports H.264, it makes no sense not to use it. I’m struggling to find a culinary equivalent, but this is like bringing a knife to a gun fight. You’re never going to win.
Both streams use stereo audio, which is also wasteful with talking-head videos, even when two speakers are involved. That’s why many prominent news organizations, including CNN and ESPN, produce in mono, with ESPN at 80Kbps and CNN at 96Kbps, both MP3. Wine Library could easily drop its MP3 audio data rate in half and its AAC rate perhaps even further, with no perceptible drop in quality.
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