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-   -   lowest h.264 bitrate settings required for best quality using FCB (http://forum.grassvalley.com/forum/showthread.php?t=13309)

africanmarty 09-30-2009 04:04 PM

lowest h.264 bitrate settings required for best quality using FCB
 
i was doing some reading in the bitrates required for quality and the firecoder was matched up against the x264 codec and was unfortunatly smashed by it.. although the time to encode x264 was smashed by FCB.

1 file encoded in x264 @ a bitrate of 1.5MB was only match by FCB when the bitrate was raised to 2.5MB it may not seem like much but this means you must raise the bitrate ~60% to achieve the same quality. So to match x264 when encoding HDV to x264 @ 16MB you would have to raise the bitrate on the spurs encode to 25.6MB. Not that it bothers me any as i have massive hard drvies and use my spurs to encode to BD and they have huge storage. I was wondering what bitrates you guys use.

what is the lowest bitrates would you use for best quality for the following resolutions when encoding using FCB to H.264 :
  • 480p/576p
  • 720p
  • 1080i or HDV
  • 1080p

i thought we could share and get opinions from others.

Regards Marty.

africanmarty 10-01-2009 10:49 PM

27 views but no comments... c'mon guys i'm just curous what bitrates you use when encoding using H264 with FCB to 480p/576p, 720p, 1080i or HDV & 1080p.

africanmarty 10-03-2009 10:44 AM

75 views.. and still nothing.

drgagx 10-03-2009 01:34 PM

You must be the first to contemplate all these options. Why not experiment yourself and post the results?

africanmarty 10-04-2009 07:11 AM

Quote:

Originally Posted by drgagx (Post 90634)
You must be the first to contemplate all these options. Why not experiment yourself and post the results?

i have found to get very good results the bit-rate must be quite a bit higher than standard h264 bitrates, similar to mpeg2 bitrates although when using these bitrates with AVC the resulting video is very good.


480p/576p - 5-6 MB/s
720p - 11-15 MB/s
1080i or HDV - 24-26 MB/s
1080p - 25+ MB/s

what bitrates have you guys found give you good results using h264 and the firecoder blu ??

istvan 10-07-2009 05:19 PM

These values are very high. FCB makes not a good job. It can be anyway, that it is because of the speed. If I use a software solution only. (Without the need to be very fast) I can achieve a pretty good quality (for 1080p) around 3-5 Mbits. Speed: x0,01 RT :-)

Regards, I.

africanmarty 10-07-2009 09:29 PM

Quote:

Originally Posted by istvan (Post 90969)
These values are very high. FCB makes not a good job. It can be anyway, that it is because of the speed. If I use a software solution only. (Without the need to be very fast) I can achieve a pretty good quality (for 1080p) around 3-5 Mbits. Speed: x0,01 RT :-)

Regards, I.

to achieve the same quality as x264 the bitrate must be raised 60% higher, since i care about quality and speed, and dont care about disk space. its a non issue.

africanmarty 10-10-2009 01:19 PM

c'mon FBC users chime in with your FCB bitrates for your resolutions.

Raja 10-13-2009 12:24 AM

The lowest i've encoded h.264 using my FCB is 17M. I found that to be excellent and better than MPEG2 HD at 17M (even though I was very surprised at how good MPEG2 HD was at a low bitrate as 17M).
H.264 seems less blocky than MPEG2 HD at low bitrates.
For the speed and quality, the FCB is excellent.

Raja 10-13-2009 12:43 AM

Just to add, the files I encoded were 1080i XDCAM HQ files recorded at 35M.


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