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I'm trying to stream media from memory on Windows 64-bit using today's nightly build.

I have tried different containers, including .wmv, .avi and .mkv. The videos play fine when loaded from file via libvlc_media_new_path or when loaded from the internet via libvlc_media_new_location. However, playing from memory with libvlc_media_new_callbacks using the read/seek callbacks and without the open callback has not been successful so far.

Looking at the log, it seems that the library is always overshooting the size of the buffer, trying to read more data than is available. When I return the actual number of bytes read (which is then less than the buffer size) from the read callback, libvlc hits EOF and then closes my media without playing it. I noticed that the seek callback is never called, regardless of the type and size of the media being played. I have attached the full log below.

I also tried using the open callback in order to specify the total size of the media, but had even less success. From the documentation it is not clear to me what datap is supposed to be. I assumed that it is a pointer to the entire in-memory media buffer. However, setting it up seems to result in a bogus Opaque pointer being sent down to the read callback. I have not debugged it yet, but wonder if the data pointer is sent instead. Either way, having the entire media data in memory is not desirable for me anyway, and I would rather get the read/seek only solution to work.

Is this feature already supported and tested? How can I investigate this further without having to dig into the VLC code? Is there a working example/test case for libvlc_media_new_callbacks somewhere?

Any help would be greatly appreciated. Thank you!

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The video I used for the following log can be downloaded here:
http://www.mediacollege.com/video/forma ... lename.wmv

This is how I initialize libvlc (I'm using video callbacks to render the frames into a texture): Log file:

The usual convention is expected. If you have data but less than requested, return what you have. If you have no data, wait until you have some. If you return 0, EOF is assumed.

Thanks a lot Remi, that helped me figure things out. I was trying to initialize the tracks before they were ready. Everything works now.

Can you share, by any chance, a documentation sample?