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fame_encode_frame(3)           fame_encode_frame          fame_encode_frame(3)


NAME

       fame_encode_frame - encode a single frame (DEPRECATED)


SYNOPSIS

       #include <fame.h>

       fame_frame_statistics_t *fame_encode_frame(fame_context_t *context, fame_yuv_t *yuv, unsigned char *shape);


DESCRIPTION

       fame_encode_frame() encodes a single uncompressed frame from yuv to a
       binary stream in  buffer, according to initialization parameters and
       optionnaly previously encoded frames. Note that in the case of video
       sequences containing B frames, it is up to the caller to present frames
       in the encoder order. Since B frames require both previous and next
       reference frames, they must be presented after both previous and next
       reference frames have been coded. For example, a "IBBPBBP" coding
       sequence must be presented in "IPBBPBB" order. This presentation order
       is also the order in which the frames should be stored in a file or
       sent to a network.

       context is the context handle previously returned by fame_open

       yuv is a pointer to the input frame. Currently, only YV12 planar
       format, also called YUV 4:2:0, is supported. The YV12 planar format
       consists in three plane, one for the Y (luminance) and two for the Cr
       and Cb (chrominance) components, the chrominance planes being
       subsampled by 2x2. These three planes are mapped linearly in memory:

                  width
       yuv ->  +=========+
               |         |
               |    Y    | height
               |         |
               +====+====+
               | Cr | height / 2
               +====+
               | Cb | height / 2
               +====+
              width / 2

       The process of converting RGB pictures to YUV12 will not be detailled
       here.

       shape represents the shape in case of video with arbitrary shape.  It
       consists in a bitmap of width x height bytes, with 255 representing an
       opaque pixel and 0 representing a transparent pixel. Values between 0
       and 255 are not supported yet.  For rectangular video, this parameter
       must be set to NULL.


RETURN VALUE

       fame_encode_frame returns a pointer to frame encoding statistics. These
       statistics include frame number, coding mode (I,P or B) for the frame,
       expected bits, actual bits used, spatial activity, and quantizer scale.
       The number of bytes written to the buffer is actual_bits/8.


BUGS

       MMX arithmetic performs bad at quality > 95%.  Encoding of B frames is
       not yet supported.  Only works when slices_per_frame has been set to 1
       in fame_init


DEPRECATED

       Usage of this function is deprecated. Use fame_start_frame ,
       fame_encode_slice , and fame_end_frame instead.


SEE ALSO

       fame_open(3), fame_init(3), fame_close(3), fame_encode_slice(3)

libfame                        Febrary 19, 2002           fame_encode_frame(3)

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