Generating proxies for anamorphic projects

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Roman Hankewycz

  • Posts: 22
  • Joined: Wed Aug 22, 2012 5:25 am

Generating proxies for anamorphic projects

PostTue Dec 09, 2014 3:40 pm

Hello,
Working on an anamorphic project I believe I've discovered a resolution conflict with the proxy generator.

The majority of our source footage is anamorphic RED footage shot at 3792x3160.
The project timeline resolution is 2048x1152.
The source clips have clip attributes set for PAR: CinemaScope, and have an Input sizing preset made to match the framing chart.

This setup works great for the majority of the film where we're reading directly from R3D files; the PAR and input sizing translations are happening on the fly and using a Red Rocket X we have good playback. However we're running into playback issues with VFX which are delivered as DPX sequences at 3792x3160. All geometry translations are the same as for the R3Ds.

I tried using RealTime Proxies but there was no improvement in playback. Next I tried generating proxies. During this attempt I realized that the proxy resolution aspect ratio is dependent on the timeline resolution aspect ratio, meaning that because the timeline is 1.78, the proxy resolutions are also locked to a 1.78 aspect ratio. When I used proxies created with such an aspect ratio (1920x1080) it resulted in a geometry shift whenever I activated proxy mode, where the proxy became "postage stamped" within the frame. Note that the playback was good despite the geometry problem.

Next I set the timeline resolution to match the source media (3792x3160) which allowed me to enter a proxy resolution matching the aspect ratio of the source (1.2). I used 1896x1580 so the proxies would be half resolution of the source. I generated the proxies, set my timeline resolution back to 2048x1152, went back to the color page and the playback was just as bad as playing the originals.

Scratching my head I opened the proxy manager and checked proxies which came back as "No." It seems that Resolve only recognizes the proxies when they match the aspect ratio of the timeline resolution (you can actually flip the timeline resolution back and forth while checking the proxy manager for proxies and see that it changes from Yes to No accordingly). In the case of an anamorphic project you can see that this isn't a viable solution.

I welcome other to check if I'm correct in my assumptions and if so I think this should definitely be addressed in an update. This issue, if I'm correct, renders the idea of proxies useless in any project with mismatched aspect ratios. Let me know what you think.

Thank you,
roman hankewycz / / colorist
H A R B O R
www.harborpicturecompany.com
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Sarin Kuruvilla

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  • Joined: Wed Aug 12, 2015 6:14 pm

Re: Generating proxies for anamorphic projects

PostWed Aug 12, 2015 6:24 pm

Anybody have a solution to this problem?
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Lee Gauthier

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  • Joined: Wed Jul 16, 2014 10:51 pm

Re: Generating proxies for anamorphic projects

PostWed Aug 12, 2015 11:50 pm

Not a solution, but a line of inquiry that may lead to one. Perhaps the DPX files don't have the proper PAR, or perhaps Resolve isn't reading them.

DPX files contain the PAR in the header, near the bottom of the list. Here's the format:

Code: Select all
typedef struct _GenericOrientationHeader
{
   DWORD  XOffset;             /* X offset */
   DWORD  YOffset;             /* Y offset */
   SINGLE XCenter;             /* X center */
   SINGLE YCenter;             /* Y center */
   DWORD  XOriginalSize;       /* X original size */
   DWORD  YOriginalSize;       /* Y original size */
   char   FileName[100];       /* Source image file name */
   char   TimeDate[24];        /* Source image date and time */
   char   InputName[32];       /* Input device name */
   char   InputSN[32];         /* Input device serial number */
   WORD   Border[4];           /* Border validity (XL, XR, YT, YB) */
   DWORD  AspectRatio[2];      /* Pixel aspect ratio (H:V) */
   BYTE   Reserved[28];        /* Reserved field used for padding */
} GENERICORIENTATIONHEADER;


The AspectRatio should be listed as the horizontal frame size divided by the vertical. If it's missing or the number is incorrect, that's the source of the problem.

If the AspectRatio data in the DPX header is correct, then I'd contact BMD about whether Resolve is equipped to read the DPX header properly. You may have to output to another format that Resolve prefers.

Good luck.

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