M65727FP Просмотр технического описания (PDF) - MITSUBISHI ELECTRIC

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M65727FP

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3.3.4 Search range expansion for Vertical direction

The non-expansion mode of vertical search range is ±7.5 / ±15.5 as explained above. At this time,

the order of priority for vectors, which have same distortions, gives the highest priority to the vector

(0,0). When the search range expansion mode of the vertical direction is specified, the range becomes

±8.0 / 16.0. It becomes possible to expand the vertical search range using multiple chips. There are

two modes for vertical expansion mode, upper-range of expansion and lower-range of expansion. The

difference between the two is in the priority order for distortion equivalent vectors. If it is specified as

upper-range, the vector (0, +8 / +16) will have the highest priority. If it is specified as lower-range, the

vector (0, -8 / -16) will have the highest priority. See Ch. 5.2 for the order of priority for vectors.

See Ch. 5.5 for the number of chips needed for the vertical search range expansion.

This mode is specified by EXTND pin as shown below. This mode must be specified before the

chip goes into operation and it should be fixed during the operation.

00: non-expansion, 01: reserved, 10: upper-range of expansion (Expansion),

11: lower-range of expansion (Expansion)

3.3.5 Half-Pel Precision/Integer-Pel Precision

The motion vector searched by M65727 is integer-pel precision during the integer-pel precision mode.

In case of half-pel precision mode, half-pel precision vector is detected using interpolated search

window image. The order of output data is shown in Table 2 (See Ch. 3.3.7). The above two modes

have different outputs.

This mode is specified by HLFPL pin as shown below. This mode should be specified before the

chip operation and should stay fixed.

0: Integer-Pel Precision mode, 1: Half-Pel Precision mode

3.3.6 External Frame Memory Data Format

M65727 is capable of selecting the external frame memory (SW image) format only when the Frame

mode is ON. This format is specified by the use of FMFMT pin as shown below. In other modes,

only field format can be used. See Ch. 5.4 for details on formats. This mode must be specified prior

to the chip operation and should be fixed during the operation.

0: Field format 1: Frame format

3.3.7 Operation Modes and Output Data

Data output from M65727 differs according to the operational modes. During the Field / Frame

mode, three sets of data group, a group of 16x16 and two groups of 16x8, are output in sequence.

Outputs from half-pel precision mode and integer precision search mode are different.

When the Field mode is ON, a data group for 16x16 block is first output. A data group for 16x8

(upper) block is output next and a data group for 16x8 (lower) is output last. It takes 21 cycles.

When the Frame mode is ON, a data group for 16x16 block is output first. A data group for 16x8

(top) is output next. And a 16x8 (bottom) block is output last. It takes 21 cycles.

Table 2 shows a set of data outputs during the Field/Frame mode in the order they are output.

In case of the Field Dual-Prime mode, Dual-Prime vector specifying code and its distortion are output in

the order shown in Table 3. It takes 3 cycles to output data.

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