VX6854LC datasheet(57/114 Pages) STMICROELECTRONICS

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VX6854LC

Video timing

The scaler is able to scale the full resolution of the sensor module down to within 10% of a

the target image size (the smallest output size is 256x192). This flexibility means that the

VX6854LC module can support a wide range of LCD viewfinder sizes and different codec

resolutions.

The VX6854LC has three scaling modes which are controlled by the scaling_mode register

as shown in Figure 16.

Figure 16. Scaling modes

Scaler quality

The scaler supports two options for the spatial sampling of the scaled image data (see

Figure 17):

•

Bayer sampled scaled image data

The sampling point for the scaler for the output Gr value appears to be in the centre of

the Gr pixel (that is, between the first and second pixels and between the first and

second rows of the original input Bayer pixel data). The R (or B) sampling points are

similarly in the centre of the R pixel (or B pixel).

•

Co-sited scaled image data

The sampling point for the Gr, R. Gb and B vales in each output ‘quad’ are functions of

the same colour input array pixels such that the spatial sampling point for all four

appears to be in the centre of the ‘quad’, that is, between the second and third pixels

and between the first and second rows.

The spatial sampling mode is controlled by the spatial_sampling register.

Pixel array output

scaling_mode register

VX6854LC output

0- no scaling

1- horizontal scaling

2- Full scaling

(horizontal and vertical)

VX6854LC Datasheet(PDF) 57 Page - STMicroelectronics