[Ffmpeg-devel] Re: [PATCH] DVCPRO50 support

Roman Shaposhnick rvs
Fri Mar 3 00:54:33 CET 2006

On Wed, Mar 01, 2006 at 08:08:56PM -0500, Dan Maas wrote:
> Hi Roman - Here is the big patch for DVCPRO50 support. Please look it
> over and get back to me with any comments. 

Hi Dan -- thanks a lot for submitting it. I'll try to take a look
at it today.

> This adds support for both NTSC and PAL with 4:2:2 sampling at 50
> Mbps, according to SMPTE 314M. The 50 Mbps mode is turned on when you
> compress or decompress 4:2:2 video (PIX_FMT_YUV422P). Otherwise it
> operates at 25 Mbps just like before.

  Seems like a reasonable choice.

> The only thing that I know is missing is a regression test for 50 Mbps
> mode. I don't know how to add one, so please help!

  I'll do that -- don't worry.

> I changed the NTSC audio sample pattern to agree with SMPTE 314M.
> The spec only allows
> 1600,1602,1602,1602,1602
> not
> 1602,1601,1602,1601,1602.

  The original sequence was produced by my camcorder and it didn't like
  anything else. However, if your distribution doesn't produce the
  "pops" during camcorder's playback -- I see no reason to disrespect
  the spec ;-)

> I changed dv_anchor to be statically allocated, which seems simpler
> and more efficient.

  I think I have a better way of dealing with it. Will add it to the
  overall patch.

> Note: I will be on travel starting March 18. I would like to get this
> patch fully applied by then.



P.S. Would applying this patch faster increase our chances of getting your 
DVCPRO HD work as the next patch ? ;-) 

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