Choppy playback
by Sal Erato
on
Dec 3, 2008 at 12:28:27 am
I designed a simple Flash web site for a client that has about 50 Flash videos. The videos vary in length and quality and I believe the largest FLV file is 20mb (most are around 12mb). Not always, (but often enough), when my client goes out to meet with a customer and tries to call up the web site, the videos play slowly and pause while downloading. I've never experienced any problems with playback so I'm having a hard time diagnosing the problem or testing solutions to see if I've solved it.
I suspect either I've not compressed the FLV's enough or the server the site is hosted on is too slow? I encoded the videos at the same frame rate they were given to me (30 fps), should I bump that down to 24 or 15? I recently found out that this site is hosted on a shared server, not a dedicated server. We're not opposed to switching hosts and or buying a better video encoder.
BTW, most of the videos were given to me in Quicktime format. I used either Quicktime Pro or Final Cut Pro to convert them to FLV.
Re: Choppy playback by mike velte on Dec 3, 2008 at 11:46:59 am
Suggest having your video buffer for about 20 seconds before playing. Also include an indicator that tells the viewer it is buffering and maybe a progress bar.
Re: Choppy playback by Daniel Low on Dec 3, 2008 at 12:31:22 pm
You might want to invest in a proper, profession encoding application. I recommend Episode from Telestream, neither Quicktime pro or FCP are going to give you the best results, they are not designed to.
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Re: Choppy playback by Sal Erato on Dec 3, 2008 at 1:39:04 pm
Thanks for the advice, I really appreciate it. I may try a combination of better encoding plus dropping the frame rate a bit. The client is open to switching to a dedicated server, but I hate to suggest switching to something that's more expensive if the problem could really be fixed by revising my files.
Re: Choppy playback by Daniel Low on Dec 3, 2008 at 1:52:36 pm
Dropping the frame rate will not help, it will just make it look worse. You could try dropping the datarate, what do you currently have it set to?
__________________________________________________________________
Please post back saying what solved your problem. It could help others, and saying 'thanks' is free!
Re: Choppy playback by Sal Erato on Dec 3, 2008 at 6:03:13 pm
Most of the clips have a datarate of around 700kbs, maybe a little higher if it's a short clip. The clip titled "video on your website" is probably the least compressed since it contains footage of the owner talking. I believe that clip could have a datarate around 1000kbs. I'm going from memory but I think when I compressed it further than that I wasn't happy with the image quality on his face and skin.
I'm on RoadRunner with a fairly new Mac and I haven't experienced any playback problems. Most of the people who will view this site are in businesses or corporate offices on what I would hope is a fairly quick network (maybe not?)
Re: Choppy playback by Mike Lacher on Dec 5, 2008 at 3:22:42 pm
Hey Sal,
I wouldn't count on corporations to necessarily have fast connections. Most of my work is delivered online to big companies, and they often have specs down around 256kbps (or lower, which is really frustrating). Switching to a dedicated server might help, but it sounds like your datarate is pretty high for web delivery (youtube is down in the 300ish range, I think). If you're encoding at 700kbps-1mbps, it might not be a bad idea to offer users other quality options. I know it sucks for users to see your work compressed down around 256kbps, but it's generally better than not seeing it at all. Depending on your application, you could also try to build some sort of bandwidth detection to automatically route users to the best possible quality for their connection.
Reducing the frame rate will help with performance, but it won't help much in terms of bandwidth. I've found FLVs at 15fps tend to play much better on slower computers. But it won't make any difference in terms of file size. It's just less keyframes to worry about.
I think Mike's comment about increasing buffer size is also a good idea.
Re: Choppy playback by Sal Erato on Dec 5, 2008 at 8:14:42 pm
Big thanks to everyone for the advice and input. I haven't made any change to the site yet. My client asked me to wait, he's working with the host company to try and move the site to a newer, faster server to see if that will help.
In the meantime I'm doing some tests and comparisons on my own site with QuickTime versus Flash.
Would I be wrong in suggesting that if you want "higher quality" video on your web site you'd opt for using QuickTime, but if you want less hassles about users having the right plugins to view your video you'd opt for Flash?
Re: Choppy playback by Mike Lacher on Dec 11, 2008 at 8:18:41 pm
Hey Sal,
I think the short answer to your question is "yes," but I have to qualify it pretty heavily.
Your question has more to do with codecs than quicktime vs. flash, as there are multiple codecs supported within those two formats. I'm guessing that when you say "Quicktime" you're talking about video encoded with H.264? And when you say FLVs you're talking about video encoded with On2 VP6? Flash now supports H.264 mp4's and even more recently actually uses H.264 encoding in FLVs.
H.264 does generally give better quality than On2 VP6 at lower bitrates. But that comes at the price of greater performance demands and less universal compatibility with users. On2 VP6 will play on any browser with Flash 8 or later (which is nearly everyone nowadays). H.264 will only play in browsers with more recent quicktime players and flash players version 9.0.115.0 or later (if the video is being played through flash).
On2 VP6 also supports an alpha channel, while H.264 does not, so if you're doing any sort of compositing in flash, On2 VP6 is still the only way to go.
