Improve company productivity with a Business Account.Sign Up

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 1604
  • Last Modified:

AVIStreamGetFrameOpen

Hi,

I got a problem with AVIStreamGetFrameOpen, it keeps failing returning a null pointer.  The problem occurs only when I specify the bitmapinfoheader which i want to!

Code Fragment:


BITMAPINFOHEADER wanted;

wanted.biBitCount = 8;
wanted.biClrImportant = 0;
wanted.biClrUsed = 0;
wanted.biCompression = BI_RGB;
wanted.biPlanes = 1;
wanted.biSize = 40;    
wanted.biXPelsPerMeter = 0;
wanted.biYPelsPerMeter = 0;
wanted.biHeight = 300;
wanted.biWidth = 300;    
wanted.biSizeImage = (((wanted.biWidth * 3) + 3) & 
                      0xFFFC) * wanted.biHeight;  

getFrame = AVIStreamGetFrameOpen(avi, &wanted);
ASSERT (getFrame != NULL);
0
RichJackson
Asked:
RichJackson
  • 3
  • 2
1 Solution
 
GloriousRainCommented:
Hi,
As your code shows:
...
biCompression = BI_RGB
...
"The problem
occurs only when I specify the bitmapinfoheader which i want to!
"->to any RGB format, the function returns NULL.
0
 
RichJacksonAuthor Commented:
Why would it do that?

It should return a pointer to a get frame object.

I tried BI_BITFIELDS and BI_RLE8

In Delphi making the equivalent API calls works!




0
 
RichJacksonAuthor Commented:
What I am saying is, there was nothing with this BITMAPINFOHEADER when i made the AVI API calls from Delphi.

Anyone any clues??


0
Free Tool: SSL Checker

Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

 
DanRollinsCommented:
From MSDN:

If the system cannot find a decompressor that can decompress the stream to the given format, or to any RGB format, the function returns NULL.

Therefore, ... Try

   getFrame = AVIStreamGetFrameOpen(avi, 0);
or
   getFrame = AVIStreamGetFrameOpen(avi, AVIGETFRAMEF_BESTDISPLAYFMT);
 
-- Dan
0
 
RichJacksonAuthor Commented:
Cheers Dan, My mistake.  I was asking for the CODEC to give me a different sized image, to what it was.
0
 
DanRollinsCommented:
Hi RichJackson,
I'm sure that you feel it was a kind thing to award me some points even thought my answer did not solve your problem.

But I'm here to inform you that a C grade in response to a comment is considered an insult.  I see that you tend to give out a lot of C's, so I'd like to remind you to please read the EE grading guildelines:
 
  http://www.experts-exchange.com/jsp/cmtyQuestAnswer.jsp#3

If you cannot get a complete answer, you should post additional comments ansking for clarifications or delete the question.

Thanks,

-- Dan
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Featured Post

Keep up with what's happening at Experts Exchange!

Sign up to receive Decoded, a new monthly digest with product updates, feature release info, continuing education opportunities, and more.

  • 3
  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now