Using the TV-Out Feature on the Zune

For the last few years, my family heads down to a friend’s beach house for some much needed vacation during the summer. The house is somewhat secluded and thus doesn’t have very good TV reception, so this year I was thinking about using my Zune 80 as a miniature Digital Video Player. That way, my kids can watch some pre-recorded movies, cartoons, TV shows, etc. on the “Big Screen” and I don’t need to bother with bring a DVD player, burning DVDs, etc. So, I began the process of investigating how I can do this with my Zune 80 device.

If you don’t already know this, you can use your Zune to output a TV-Composite signal from the headphone jack using a special cable (it’s the same cable used for the newer iPods devices). My Zune A/V Kit came with such a video cable, so I had all the necessary hardware to pipe video from my Zune to a standard TV set. Note, that using a TV-Composite signal doesn’t offer you the best video quality (comparable to the output from an older VCR). If I was really picky and wanted the best quality possible, I could invest in a new Zune dock and use video component out signals, however, my plan is to watch videos on an older TV set so doing so would be overkill in this application.

The next step is to create video files that would playback reasonably well on a standard TV set. Most of my current Zune videos are in 320×480 resolution format (30 fps). This works great for playback on my Zune at 700 kbps video rate, however, it looks pretty grainy when viewing on a TV display. So as a test, I converted a partial TV show (Source: MPEG2, 720×480, 30 fps, 8000 Kbps, 7 minutes duration) with several different video settings. Below is what I tried, and my comments regarding playback on a standard TV screen:

320×240, 30 fps, 700 Kbps (43 MB) – This is the standard video settings that I use on my Zune, and the TV display image is very grainy. In addition, there’s a lot of “video tearing”, where there is pixelation and blurring during any motion.

640×480, 30 fps, 700 Kbps (43 MB) – The 640×480 resolution looked acceptable, and the 700 Kbps was fine when the actors didn’t move around very much in the scene. With moderate to high motion in the scene, noticeable video tearing and pixelation occurred.

720×480, 30 fps, 700 Kbps (43 MB) – At 720×480 I actually noticed more video tearing and pixelation, when intuitively I would think the video quality would be better. Also, the file size is the same as the 320×240 and 640×480 resolution, which seems strange.

640×480, 30 fps, 1500 Kbps (85 MB) – The 640×480 resolution looked acceptable, and the video tearing wasn’t as noticeable compared to using 700 Kbps.

640×480, 30 fps, 3000 Kbps (163 MB) – These settings produced the best playback quality of all that I tested, however, there still was a slight amount of video tearing during the high speed motion in the scenes.

Note: All video files had an audio bit rate of 128 Kbps, and I used a Constant Bit Rate (CBR) for both the audio and video settings.

Now, I was standing about 3 feet away from the TV when I was doing these tests, so it might not be too big if a deal if I was sitting on a couch at 7-8 ft away. The 640×480 resolution seemed to work best, and the only matter to decide on was the level of acceptable video tearing based on the different video bit rates. So I would suggest using the 700 Kbps if you’re concerned with file size and don’t mind seeing occasional video tearing, or 1500 Kbps if you’re not too concerned on file size and want better video quality, and finally 3000 Kbps if you really want to minimize video tearing and don’t care about file size.

What’s odd about these tests, is that file size for the first three video files (all at 700 Kbps) were the same. I would have thought that the high resolution files would have a larger size, but that didn’t seem to be the case. It appears that the video bit rate governed the file size (maybe because the video setting I used was CBR (Constant Bit Rate) instead of VBR (Variable Bit Rate))?

As a test, I made a few more video files using a variable bit rate (VBR) for the video, while keeping the audio bit rate constant (since this is a requirement to avoid transcoding during Zune syncing). So basically, the video bit rate that I specify in the conversion will be an “average” rate, while the actual rate can vary up and down when needed. Here’s the specs on the 2nd set of test files I created:

320×240, 30 fps, 700 Kbps (average rate) VBR (43 MB) – This resulted in a video file about the same size as the CBR video rate, but the peak video bit rate is 1150 Kbps.

640×480, 30 fps, 700 Kbps (average rate) VBR (43 MB) – This resulted in a video file about the same size as the CBR video rate, but the peak video bit rate is 1122 Kbps. Again, the file size between the two different resolutions is the same for some reason.

640×480, 30 fps, 1500 Kbps (average rate) VBR (84MB) – This resulted in a video file about the same size as the CBR video rate, but the peak video bit rate is 2428 Kbps.

With all of these files using VBR, the video tearing was significantly reduced (in my opinion), with no sacrifice in file size. In fact, the 320×240 video file actually looked ok when I was sitting on my couch about 9 feet away. So in a pinch, playing 320×240 videos created with VBR for the video bit rate might be sufficient.

Conclusion

I’ve concluded that for all my future videos, I’m going to use the Variable Bit Rate (VBR) for the video processing, as it minimizes video tearing without increasing the size. In addition, I recommend using the settings of 640×480, 30 fps, 1500 Kbps VBR (video) for those video files which you plan to watch on a standard TV set.

So, it appears that I’ll be sufficiently armed to handle my kids with my Zune 80 on our next summer vacation!

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14 thoughts on “Using the TV-Out Feature on the Zune

  1. harry says:

    I really appreciate the way you do your testing. Very methodical. Any chance you could make a .prx file that I could use with Windows Media Batch Encoder that would incorporate these settings?

  2. zunetips says:

    harry: Yes, I can create a prx file for you. Which settings do you want in that file?

  3. harry says:

    Probably these (from your post): “640×480, 30 fps, 1500 Kbps VBR (video)”

  4. zunetips says:

    harry: you can download this profile (640×480, 30 fps, 1500 kbps VBR) from this link. If you want to change the settings for this profile, just double click on it to bring up the editor.

  5. harry says:

    Thanks!
    Any chance you could add a feature to your blog for an rss feed for comments only? I get your regular feed, but keep on forgetting to come back and check the comments…until I see you’ve posted another article.

  6. zunetips says:

    harry: Unfortunately, I didn’t see an option in the WordPress software (which drives this Blog) to allow for rss feeds of comments.

  7. harry says:

    LOL you suck. ha ha .. couldn’t resist that, after reading your post today. Guess I’ll just have to keep checking back when you have new posts. So far, based on your posts and recommendations, I’ve found great prices and purchased an AV connection kit, premium earbuds, aluminum case, and a car charger. I love my zune!

    My only complaint is with my current setup for listening in my car. It’s a cassette car-kit, and it’s very buzzy. Wish I had a way to plug directly into an aux input, but I don’t want to go through the $$ of modding my factory radio. It will definitely be a required feature of my next vehicle.

  8. zunetips says:

    harry: You might check out the FM transmitters that are available for generic MP3 players. I saw a few on http://www.buy.com going for $15 US. I’d also check out http://www.amazon.com for good deals. They might work better than the old-fashion cassette kits (man, that really sounds old now!).

  9. Jordan says:

    hey I was just wondering if the zune 80 can be synced at 640* 480 without converting. I really wanted good tv output with my zune 30 but when I convert a movie to 640*480 and try to sync, it always has to convert it back to 320*240 first. 😦 and then the quality isn’t that great. Does the zune 80 hold higher quality videos and just playes it on the zune at 320*240?

    Thanks

  10. zunetips says:

    Jordan: Yes, you can sync 640×480 video on your Zune 80 (that is what I did for the tests mentioned on this page). You need to make sure the other video settings (fps, bit rate, etc) are within the specs for your Zune. Check out my “Zune Specs” page for more details.

  11. Matt says:

    Hey, I’m confused about one small point. You encoded a video into “640×480, 30 fps, 1500 Kbps (average rate) VBR (84MB)” but the 1500 Kbps is way outside the limit that your zune specs page dictates. Does this really sync to a zune 80 without the need for it to be transcoded first?

    Extremely helpful weblog, thanks very much.

  12. zunetips says:

    Matt – 1500 Kbps = 1.5 Mbps, which falls within the Zune specs that I quoted on the “Zune Specs” page of this blog. A converted video file with these specs should not transcode.

  13. mados123 says:

    @zunetips. Been away for sometime and remembered to use your blog as a resource for my next project. First off, excellent post here. Great to see work like this. I’m setting up a media server and wanted to make files that can be used for the Zune as well as over the home network to other computers and my HTPC. Regarding your research, did you try 720 x 480, VBR at all? I would be curious to see your findings as maybe the VBR addresses the tearing and pixalation you experienced with CBR and as you said, seems like it should be better than 640×480. Please let me know what the outcome is. Thanks and keep up the great work!

  14. zunetips says:

    mados123 – I can’t remember if I tested a 720×480 resolution video conversion. It may be just as good as the 640×480 resolution that I tested (with VBR), but since “good” is a very subjective adjective that would just be my opinion! 🙂

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