Question

Previously I used ffmpeg on windows (0.52 build I found somewhere). Now I am porting to linux and to latest ffmpeg. So far I got 4 errors in 2 lines
On such simple line:

size = avpicture_get_size(pix_fmt, nWidth, nHeight);

I get:

  initializing argument 1 of ‘int avpicture_get_size(PixelFormat, int, int)’    C/C++ Problem

and

invalid conversion from ‘int’ to ‘PixelFormat’      C/C++ Problem

And On such simple line

 avpicture_fill((AVPicture *)picture, picture_buf, pix_fmt, nWidth, nHeight);

I get:

 initializing argument 3 of ‘int avpicture_fill(AVPicture*, uint8_t*, PixelFormat, int, int)’       C/C++ Problem

and

invalid conversion from ‘int’ to ‘PixelFormat’      C/C++ Problem

Code compiled and worked perfectly under Windows ffmpeg 0.52 but now gives such error on linux g++ on ffmpeg 0.6.1

How to fix such errors?

Answer 1

PixelFormat is defined as an enum in pixfmt.h. I think that the problem is that in C++, there is no implicit conversion from an int to an enum. So, you need to explicitly convert the int to PixelFormat. Try this:

size = avpicture_get_size(static_cast<PixelFormat>(pix_fmt), nWidth, nHeight);

or you could just make pix_fmt a PixelFormat instead of an int.

I don’t know why this worked previously, because C++ does not allow int to enum conversion without a cast. I think C does allow this though so maybe it was being compiled s C previously.

Edit: I just saw the API change from int to enum. So that is why it compiled previously.