mvGetImageWidth(3dm)mvGetImageWidth(3dm)NAME
mvGetImageWidth, mvGetImageHeight, mvGetImageRate, mvGetImageCompression,
mvGetImageInterlacing, mvGetImagePacking, mvGetImageOrientation,
mvGetSpatialQuality, mvGetTemporalQuality, mvSetImageRate - get and set
the properties of a an image track
SYNOPSIS
#include <dmedia/moviefile.h>
int mvGetImageWidth( MVid imageTrack )
int mvGetImageHeight( MVid imageTrack )
double mvGetImageRate( MVid imageTrack )
const char* mvGetImageCompression( MVid imageTrack )
DMinterlacing mvGetImageInterlacing( MVid imageTrack )
DMpacking mvGetImagePacking( MVid imageTrack )
DMorientation mvGetImageOrientation( MVid imageTrack )
double mvGetSpatialQuality( MVid movie )
double mvGetTemporalQuality( MVid movie )
DMstatus mvSetImageRate( MVid imageTrack, double framesPerSecond )
DESCRIPTION
All of the data accessed by these functions can also be accessed using
mvGetParams(3dm) and mvSetParams(3dm).
mvGetImageWidth returns the x size (in pixels) of the images stored in
the track.
mvGetImageHeight returns the y size (in pixels) of the images stored in
the track.
mvGetImageRate returns the number of frames per second that are shown
when playing the movie.
mvGetImageRate returns the default frequency for key frames when frames
are being added and compressed in the movie library using a compression
scheme that supports key frames.
mvGetImageInterlacing returns the interlacing format for the image, which
can be one of: DM_IMAGE_NONINTERLACED, DM_IMAGE_INTERLACED_EVEN,
DM_IMAGE_INTERLACED_ODD. NTSC video interlacing is "even" and PAL video
interlacing is "odd". An interlaced image consists of a contiguous pair
of fields. The field which is packed first into the image data is always
the field which is displayed first temporally.
mvGetImageCompression returns the name of the compression scheme that is
used to compress the images. The strings returned are owned by the movie
library and must not be freed. If an application needs to keep the
returned string, it should be copied.
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mvGetImageWidth(3dm)mvGetImageWidth(3dm)
mvGetImagePacking returns the format of the individual pixels in the
image, which can be one of: DM_PACKING_BGR, DM_PACKING_XBGR,
DM_PACKING_ABGR, DM_PACKING_RBG323, DM_PACKING_BGR233,
DM_PACKING_GRAYSCALE, DM_PACKING_YCbCr, DM_PACKING_YCbCr422,
DM_PACKING_XRGB, or DM_PACKING_RGB555.
mvGetImageOrientation returns the order in which the scan lines of the
image are stored. The orientation will be either DM_BOTTOM_TO_TOP or
DM_TOP_TO_BOTTOM.
mvGetSpatialQuality returns a double between 0 and 1.0 that indicates the
spatial quality of the image track.
mvGetTemporalQuality returns a double between 0 and 1.0 that indicates
the temporal quality of the image track.
These "get" functions have no indication of error return. The movie
library guarantees that all image tracks have all of these parameters
defined.
mvSetImageRate stores a new value for the image rate parameter. It
returns DM_SUCCESS or DM_FAILURE. The value of the image rate parameter
should be between 0.25 and 100.0. The other parameters cannot be changed
after a track has been created because they would invalidate the data
stored in the track.
SEE ALSOmvIntro(3dm), mvCreate(3dm), mvOpen(3dm), mvAddTrack(3dm),
mvOptimize(3dm), mvGetErrno(3dm).
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