What bit rate should a FLV trailer be?
 

For a SD video trailer full size, what do you think is too high a bit rate?

720 x 480 flv? 500-1000 maybe more, depends on a few factors in my experience, like what codec, how much motion is in the clip, and what kind of lighting.

I just got adobe media encoder, trying to encode a flv (hardcore scene) shot in SD. Lots of movement, fast cuts and such. Its all well lit and shot on SD 3 chip cam, not HD.

The source file is 720 x 480 NTCS avi and I'm sizing it down to 620. Using the ON2VP6 codec, tried both CBR and VBR, tried single and double pass with bit rates ranging from 600 - 1200 and am just not happy with the results.

My member videos are h264 and they look great but it seems when I use a h264 as a trailer (45 second clip) it doesn't stream as fast as a short flv does so I'm trying it this way but very unhappy with the results.

:helpme

As far as i know flv is a container and you can use differnet codecs in that container including h264/x264,or is that what you ment when you tried h264. The way you typed it is you used h264 with a container other then flv?

I'm ok with .mp4 files it's the .flv I am having problems with.

Want to know what a 500 kbps clip looks like, go to any tube site and full screen a scene. I'll save you the time. It looks like shit. You need at least 1500 kbps to even remotely approach anything looking close to DVD quality.

1150 8chars

Whatever looks good. The better your trailer looks, the more likely people are to buy...

Thanks to those who replied.

The correct answer is: as high as you can make it, but still maintain your site's bandwidth budget and server load, AND support as many surfers as you can.

Anything over 1mbps is pushing it for most surfers, as they simply don't have the sustainable bandwidth. People will accept lesser quality video but not constant stopping to refill the buffer.

If you are truly steaming your content you can set up bitrate negotiation and serve the highest bandwidth version the surfer's connection can accommodate.

Some tricks you can use save on the bitrate while not greatly sacrificing quality:

* Encode in mono, 22050 kHz.
* Set a larger keyframe distance, maybe every 3-6 seconds. The default is usually 1 second.
* Set the frame rate 15 or 20 fps. Won't work with lots of action as it could cause strobing.
* Consider a slightly smaller video, but remember to actually encode the video at the same size as your player, and be sure the H and W dimensions are both evenly divisible by 16. (FLVs have a preset macroblock size of 16x16 pixels.)

Depending on the encoder you use it may not do a good job converting from interlaced content. If that's what's in your AVI you'll want to remaster it de-interlaced first.

You want VBR 2-pass. No single pass encode will ever give you the best quality. The first pass is to get a kind of encoding summary, and the second pass is where the actual encoding is performed.

There is no sense in a CBR encode for video, as this will constrain the bitrate for everything. You want to use VBR, set a higher average bitrate, and allow for a reasonable peak bitrate to handle the fast motion.

I don't have the latest Adobe enoder, but I know the older version for Flash 8 just doesn't have the functionality to play with a lot of settings. You need either On2 Flix Pro, or a version of Sorenson Squeeze that does FLV.

@abshard: FLV is technically a codec that also uses a proprietary container. There are only two: Sorenson Spark and VP6. (Actually, not quite true. There are two variations of VP6, VP6-S and VP6-E. You use VP6-S for HD content. Adobe confuses things by using an "F4V" extension for H.264 videos meant for Flash Player. These are really MP4 containers.)

thanks for this!

I second that, this was very informative. Thanks for sharing.

Now THAT is the sort of info I have been looking for. Maybe one of the most informitive posts ever on this board. Thank you sir. :thumbsup

I didn't know this at all, thanks.

Does the divisible by 16 rule apply to all formats or only FLV? I'm curious about WMV and mp4 as well.

Hopefully the info is accurate! :winkwink:

On the tricks to slim down the bitrate, what you're really looking for is tradeoffs in the "bit budget." By reducing the bitrate requirement in one way, you can then increase the overall bitrate without materially increasing the size of the file. Since your source has a lot of motion it's going to be tricky for you.

All compressed video has a set macroblock size (though some, like H.264, have variable block size), and the 16-pixel increments is a good rule of thumb anyway. It's just that for Flash and FLV it tends to be more important.

I thought I'd also mention that not all FLV players automatically apply smoothing and deblocking. It's something they can toggle off and on in Actionscript, and is independent of the video file itself. See if your player has a smooth/deblock option, and make sure it's set to On. Or try your video in one or two different players.