MFCopyImage

MFCopyImage

• JGiers

  yeah im passing in right values..i even coded it manually like your above example but to no avail.

  the image is progressive

  
  

• Acanthus

  Hi Mike,

  Thank you for your feedback. I think the image format was a problem. I tried using IYUV instead of NV12 and I actually got color but I noticed some things had changed. For one, only one call to MFCopyImage was needed (2 would crash the program). Also I had to multiply the width by 2 in the MFCopyImage argument. I was under the impression that MFCopyImage copied only the Y plane first And why did I have to multiply the width by 2 The original yuv stream is in 320x240 (and MF gives a deststride and srcstride both of 640).

  Thanks,

  
  

• WXS123

  I'm running out of ideas. Some possibilities:

  - A problem with how you've constructed the NV12 media type (So that the renderer is mis-interpreting the image format.)

  - If I recall, you've got an uncompressed source plus a copy transform derived from the MFTGrayScale sample. Maybe you're hitting some bug in the MFTGrayscale sample

  I assume you're QI'ing the buffers for IMF2DBuffer. Can you describe the corrupted image

  - Diagonal stripes (which would point to a stride issue)

  - Green/magenta colors (maybe swapped chroma bytes, or an incorrect format description, or some kind of off-by-N copy error.)

  - something else

  ----------------------------------------------------------------------------
  Mike Wasson, SDK Documentation
  This posting is provided "AS IS" with no warranties, and confers no rights. You assume all risk for your use.

  (c) 2007 Microsoft Corporation. All rights reserved.

  
  

  
  
  

• Al33327

  Hi Mike,

  This is what I have done, but the color is all messed up as if the UV plane isn't being copied properly. Any ideas

  
  

• bonni

  It copies one plane at a time. To copy the U/V planes, you need to

  1. Do some pointer arithmetic to find the start of the U/V plane, in both the source and destination buffers.

  2. Call MFCopyImage again.

  So for NV12 it will be something like:

  pSrc = pScanLine0 + (src_stride * height)

  pDest = pDest + (dest_stride * height)

  MFCopyImage(pDest, dest_stride, pSrc, width_in_bytes, height/2)

  (I haven't double checked this, so my math might be wrong...)

  I will update the SDK docs to reflect this behavior - thanks for bringing this to my attention!

  ----------------------------------------------------------------------------
  Mike Wasson, SDK Documentation
  This posting is provided "AS IS" with no warranties, and confers no rights. You assume all risk for your use.

  (c) 2007 Microsoft Corporation. All rights reserved.

  
  
  

• Alex Bates

  MFCopyImage is basically an optimized version of this:

  for (DWORD i = 0; i < dwLines; i++)
  {
  CopyMemory(pDest, pSrc, dwWidthInByes);
  pDest += lDestStride;
  pSrc += lSrcStride;
  }

  Are you sure you're passing the right values for the second call to MFCopyImage Other than that, I'm out of suggestions. :-(

  (btw - Is the image interlaced or progressive )

  ----------------------------------------------------------------------------
  Mike Wasson, SDK Documentation
  This posting is provided "AS IS" with no warranties, and confers no rights. You assume all risk for your use.

  (c) 2007 Microsoft Corporation. All rights reserved.

  
  
  

• Abel Khumalo

  Hi Mike,

  So you are saying the MFCopyImage function only does the Y plane

  
  

• akin_l

  This sounds like it copied only the Y plane. You might have to make separate calls to copy the U and V planes. (You'll need to do some pointer arithmetic.) I'll do some research and follow up.

  ----------------------------------------------------------------------------
  Mike Wasson, SDK Documentation
  This posting is provided "AS IS" with no warranties, and confers no rights. You assume all risk for your use.

  (c) 2007 Microsoft Corporation. All rights reserved.

  
  
  
• MFCopyImage