HD Playback, A Question for BOB! (^_^) at DVinfo.net

James Burland · February 22nd, 2007, 02:46 AM

Hello all,

I've been looking at footage (.m2t) taken from a Canon HV10. I've been using VLC, and I've noticed that the footage seems to look better (most of the time) when using the 'Bob' option under the Deinterlace menu. In all honesty, in looks like 60fps. Could anyone quickly explain what 'Bob' is doing, and why the video looks so smooth?

Thank again.

Graham Hickling · February 22nd, 2007, 07:43 AM

A dumb bob deinterlaces each field of interlaced footage and plays each one back as a frame .... so that you get double-framerate progressive footage.

The better ones also adjust the image vertically (by an amount equivalent to one scan line, I think) to reduce flickering.

A smart bob doubles the framerate in the same way, but only deinterlaces those parts of the image that are moving, thereby retaining more detail.

James Burland · February 22nd, 2007, 08:18 AM

Thanks Graham . . . that's explains things nicely.

I have a HV10 arriving in the next couple of days - I love that 60fps look, is there any way of translating that over into another codec, such as H.264? I know that VLC does transcoding, could I use that perhaps?

Graham Hickling · February 22nd, 2007, 08:29 AM

You can easily apply a bob using freeware tools like avisynth or virtualdub, if you are familiar with either of those.

Otherwise, some of the commercial encoders may do it - for example I know Procoder does. And After Effects will do it through "interpret footage".

You may find it easiest to produce an intermediate bobed avi file, that you then feed into your encoder.

EDIT: actually yes, VLC may well do it ... I've just never tried it that way!

February 22nd, 2007, 02:46 AM	#1
James Burland Regular Crew Join Date: Feb 2007 Location: Weymouth, UK Posts: 29	HD Playback, A Question for BOB! (^_^) Hello all, I've been looking at footage (.m2t) taken from a Canon HV10. I've been using VLC, and I've noticed that the footage seems to look better (most of the time) when using the 'Bob' option under the Deinterlace menu. In all honesty, in looks like 60fps. Could anyone quickly explain what 'Bob' is doing, and why the video looks so smooth? Thank again.

February 22nd, 2007, 07:43 AM	#2
Graham Hickling Trustee Join Date: May 2004 Location: Knoxville, Tennessee Posts: 1,669	A dumb bob deinterlaces each field of interlaced footage and plays each one back as a frame .... so that you get double-framerate progressive footage. The better ones also adjust the image vertically (by an amount equivalent to one scan line, I think) to reduce flickering. A smart bob doubles the framerate in the same way, but only deinterlaces those parts of the image that are moving, thereby retaining more detail.

February 22nd, 2007, 08:18 AM	#3
James Burland Regular Crew Join Date: Feb 2007 Location: Weymouth, UK Posts: 29	Thanks Graham . . . that's explains things nicely. I have a HV10 arriving in the next couple of days - I love that 60fps look, is there any way of translating that over into another codec, such as H.264? I know that VLC does transcoding, could I use that perhaps?

February 22nd, 2007, 08:29 AM	#4
Graham Hickling Trustee Join Date: May 2004 Location: Knoxville, Tennessee Posts: 1,669	You can easily apply a bob using freeware tools like avisynth or virtualdub, if you are familiar with either of those. Otherwise, some of the commercial encoders may do it - for example I know Procoder does. And After Effects will do it through "interpret footage". You may find it easiest to produce an intermediate bobed avi file, that you then feed into your encoder. EDIT: actually yes, VLC may well do it ... I've just never tried it that way!