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blues
07-12-2010, 03:51 AM
my settings are


AVCHD 50 44H 33L 56 60
GOP 5
native 24p ticked
and I am gettings 115 megabits/s

I used Mpeg stream to deinterlace...

is this possible? am using the class 6 sd card

Martin Koch
07-12-2010, 04:52 AM
I used Mpeg streamclip to deinterlace...

Not only that you also converted to another video format didn't you? What you're seeing is the bitrate of that format.

noirist
07-12-2010, 04:58 AM
Also lower GOP means less compression means higher bit rate for the same image quality.

svecher
07-12-2010, 06:52 AM
I used Mpeg stream to deinterlace...

What's the purpose of deinterlacing progressive footage?

Ian-T
07-12-2010, 06:58 AM
I used Mpeg stream to deinterlace...

Huh? This does not make sense.

blues
07-12-2010, 02:26 PM
why not....looks smoother to me.

anyway the settings looks stable so far. the low GOP seems to work.Does that mean the file size will be bigger since its less compression?

hsitz
07-12-2010, 02:49 PM
why not....looks smoother to me.


I think the point is that if you're recording in native 24p then there couldn't possibly be anything to deinterlace. The difference you're seeing is either (1) the result of something other than deinterlacing or (2) purely imagined or (3) the footage from the camera is not really native 24p.

The other issue is that if you're converting the AVCHD file to mpeg with MPEG Streamclip, then measuring the bitrate of the mpeg, you're not measuring the bitrate of the original AVCHD clip that the camera wrote.

Shinobi Productions
07-12-2010, 03:48 PM
I think the point is that if you're recording in native 24p then there couldn't possibly be anything to deinterlace. The difference you're seeing is either (1) the result of something other than deinterlacing or (2) purely imagined.

The other issue is that if you're converting the AVCHD file to mpeg with MPEG Streamclip, then measuring the bitrate of the mpeg, you're not measuring the bitrate of the original AVCHD clip that the camera wrote.

Werd

blues
07-12-2010, 03:48 PM
why dont you all try it and prove me wrong!!!!!
the original after log and transfer dowload from FCP with AVCHD preference prores 422 says 116 mbps

then get the free mpeg stream and you will see the option deinterlace still present so check the deinterlace option and click make a movie option
the new bitrate/sec is 115mbps

then compare the image...the de- interlaced clip is smoother.

I suspect the 24p option is realy not the real thing, you still need to de interlace.It appears in Jes as well. but in jes the option inverse telecine disappears meaning the 24p checked is working on another level.
I suggest you try the settings and go thru the process and tell me if I am doing something wrong.Thanks

BTW I use the latest ptool 3.40D and my camera recording option is in AVCHD in FHD mode not mpeg

brainflakes
07-12-2010, 03:58 PM
Unlikely, I've been testing a class 6 card and found that around 28mbit is the maximum stable bitrate you can use. 32mbit works most of the time but will occasionally crash out with the card write speed error on demanding subjects.

modulr
07-12-2010, 04:02 PM
Once you log and transfer in FCP, you have transcoded the clip. Thus your mbps will be different as it's likely you are now using a codec that's FCP friendly. If you want to see what the real clip bitrate is, you need something that can peak at the MTS file on your SD card. MediaInfo Mac will let you get bitrates right from the MTS file. Try that, and you'll see you are not getting 100+ mbps with AVCHD. The AVCHD tends to choke the card (class 10) right around 54mbps or so.

Deinterlacing progressive footage really makes no sense btw.

blues
07-12-2010, 04:02 PM
please try it as I am very interested.I have been using it with a class6 card and for 3 days now I have not experienced a crash.looks good so far......am in the tropics so the different light contast is severe...but it holds.

blues
07-12-2010, 04:11 PM
Once you log and transfer in FCP, you have transcoded the clip. Thus your mbps will be different as it's likely you are now using a codec that's FCP friendly. If you want to see what the real clip bitrate is, you need something that can peak at the MTS file on your SD card. MediaInfo Mac will let you get bitrates right from the MTS file. Try that, and you'll see you are not getting 100+ mbps with AVCHD. The AVCHD tends to choke the card (class 10) right around 54mbps or so.

Deinterlacing progressive footage really makes no sense btw.

ok you are right,it says 27mbps when original MTS via media info and I see it varies from shot to shot. but it still does not answer why the deinterlacing option still exist when the mpeg stream is used. please explain thanks

modulr
07-12-2010, 04:17 PM
if you look where the deinterlace options are in mpeg streamclip.. you'll see it say's "deselect for progressive movies." It doesn't prevent you from selecting deinterlace, but it clearly says not to. :)

blues
07-12-2010, 05:18 PM
thank you now its all clear to me.....