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Video Bit Rate - what does it mean?

PostPosted: Thu Jul 11, 2013 2:33 pm
by soundcheck
Hi there.

A beginner question.

I'm wondering what video bitrate actually means and what impact it will have on image quality.

If I look at a 1:1 copy of a BD. I look at > 20000kbit/s.

My Sony accepts 17Mb/s max.

What does it actually mean?

THX

Cheers

Re: Video Bit Rate - what does it mean?

PostPosted: Thu Jul 11, 2013 3:23 pm
by DenyAll
In simple terms bit rate specifies how much information is transmitted in a second. For a given video coding scheme then the more information the TV can get the better the picture quality. The underlined bit is important, for example a video encoded with h264 can produce an equivalent quality to that of mpeg2 at a much lower bit rate (and smaller file size - bit rate and file size are related).

Your TV is rated at 17Mbps over DLNA. If you exceed this rate you will likely see stuttering when playing the video (if the TV plays it at all). These files will need to be transcoded to reduce the bit rate. The good news is you're not likely to notice the quality loss from +20Mbps to 17Mbps. The bad news is you need a fair bit of CPU power to transcode at this rate.

Re: Video Bit Rate - what does it mean?

PostPosted: Thu Jul 11, 2013 3:42 pm
by soundcheck
Thx a lot.

Is anybody aware of a device that accepts >17Mb/s ?

Re: Video Bit Rate - what does it mean?

PostPosted: Thu Jul 11, 2013 11:29 pm
by atc98092
soundcheck wrote:Thx a lot.

Is anybody aware of a device that accepts >17Mb/s ?


My Sony SNP-N200 boxes claim I am getting a 50Mbit rate, but I don't know exactly what that display is supposed to mean. Does it include the audio stream? Is it lying? I really don't know. However, since it shows a bit rate I can compare it to some Internet sources. Streaming Crackle I see 1-2Mbps, some other online sites are <1. Most of my DVD rips are in the 5-9Mbps range. It's only a few Blu-Ray rips that show this extreme bit rate. Most are closer to 25-30Mbps.