vlcreatebuffer(3dm)

NAME
     vlCreateBuffer, vlDestroyBuffer - IRIS VL buffer create and destroy
     routines

SYNOPSIS
     #include <dmedia/vl.h>

     VLBuffer vlCreateBuffer(VLServer svr, VLPath path, VLNode node, int nframes);
     int vlDestroyBuffer(VLServer svr, VLBuffer buffer);

DESCRIPTION
     vlCreateBuffer creates and returns a handle to a buffer which can then be
     registered with a path and used to send or receive video data.

     A VLBuffer consists of a list of frame-sized regions of memory each with
     an associated header block. Buffers are needed for transferring data to
     or from memory nodes. To receive a frame, the reader calls one of
     vlGetNextValid or vlGetLatestValid , and to free that frame calls
     vlPutFree.  To send a frame, the writer calls vlGetNextFree, copies the
     data to be sent into the acquired buffer, and then vlPutValid to send
     that frame.

     Various controls affect buffer size. Setting controls which affect frame
     size should be done prior to calling vlCreateBuffer. These controls
     include VL_CAP_TYPE, VL_PACKING, VL_SIZE, VL_ZOOM, VL_OFFSET and
     VL_TIMING.

     vlDestroyBuffer destroys a buffer and frees any associated resources.

DIAGNOSTICS
     vlCreateBuffer returns a buffer handle upon successful completion.
     Otherwise, NULL is returned and vlErrno is set to indicate the error.

     vlDestroyBuffer returns 0 if the server handle is valid, otherwise it
     returns -1 and sets vlErrno to VLBadServer.


SEE ALSO
     vlCreatePath(3dm), vlBeginTransfer(3dm), vlRegisterBuffer(3dm),
     vlGetNextValid(3dm), vlSetControl(3dm)