SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
From the paxel starting coordinate (the VISS_RAWFE_H3A_AFPAXSTART[27:16] PAXSH and VISS_RAWFE_H3A_AFPAXSTART[11:0] PAXSV bit fields) specifies the starting point of the paxel grid, with respect to first pixel of the input image frame.
The paxel starting coordinate also indicates which color pixels are extracted if VF is enabled (that is, if VISS_RAWFE_H3A_PCR[20] AF_VF_EN = 1). Normally, either Gr or Gb is used for AF, but it is not important to the hardware whether it is red, green, or blue. If VF is not enabled, then the red, green, and blue pixel extraction is controlled by the VISS_RAWFE_H3A_PCR[13:11] RGBPOS bit field to extract the correct colors from the input stream. Figure 6-75 shows the available options for this bit field. The red and blue pixel positions are interchangeable. For each 2 × 2 grid, the green pixels are summed to create a single value. Because of this, the amplitude of the green output contains 2 pixels, while the red and blue outputs each contain 1 pixel.
Each paxel is VISS_RAWFE_H3A_AFPAX1[23:16] PAXW × VISS_RAWFE_H3A_AFPAX1[7:0] PAXH (width × height) pixels. Inside each paxel, horizontal FV can skip lines, operating on one every VISS_RAWFE_H3A_AFPAX2[16:13] AFINCV lines. Vertical FV can skip columns, operating on one every VISS_RAWFE_H3A_AFPAX2[20:17] AFINCH columns. Up to 32 columns are supported for each paxel. If floor (PAXW/AFINCH) >= 32, only the first 32 designated columns are operated on. Because PAXW, PAXH, AFINCV, and AFINCH are all even numbers, AF always operates on the same green color, Gr or Gb. IIR filters for the horizontal FVs start operation at column VISS_RAWFE_H3A_AFIIRSH[11:0] IIRSH.
Figure 6-76 shows the RAWFE H3A horizontal/vertical fv paxel configuration.
(VISS_RAWFE_H3A_AFPAXSTART[27:16] PAXSH) + (VISS_RAWFE_H3A_AFPAX2[5:0] PAXHC) × (VISS_RAWFE_H3A_AFPAX1[23:16] PAXW) <= [(Frame width on VP) – (VISS_RAWFE_H3A_LINE_START[15:0] LINE_START)] <= 4096
Table 6-139 lists the bit fields that configure the size and number of paxels.
Bit Field | Bit Width | Description |
---|---|---|
VISS_RAWFE_H3A_AFPAX1[23:16] PAXW | 8 | Paxel width (in pixels) |
VISS_RAWFE_H3A_AFPAX1[7:0] PAXH | 8 | Paxel height (in lines) |
VISS_RAWFE_H3A_AFPAX2[5:0] PAXHC | 6 | Paxel count for horizontal direction |
VISS_RAWFE_H3A_AFPAX2[12:6] PAXVC | 7 | Paxel count for vertical direction |
VISS_RAWFE_H3A_AFPAX2[16:13] AFINCV | 4 | Line increments in a paxel |
VISS_RAWFE_H3A_AFPAX2[20:17] AFINCH | 4 | Column increments in a paxel |
VISS_RAWFE_H3A_AFPAXSTART[27:16] PAXSH | 12 | Paxel start position H |
VISS_RAWFE_H3A_AFPAXSTART[11:0] PAXSV | 12 | Paxel start position V |
VISS_RAWFE_H3A_AFIIRSH[11:0] IIRSH | 12 | IIR filter start position |
The H3A AF engine also has an option for an advanced or normal stats collection mode. When 0xCA00 is written to the VISS_RAWFE_H3A_ADVANCED[31:15] ID bit field, then VISS_RAWFE_H3A_ADVANCED[0] AF_MODE can be used to toggle between normal and advanced AF stats collection mode. When the advanced AF stats collection mode is enabled, the ZEROS section of the AF paxel packet is filled with the sum of the maximum FVs, regardless of the color, from HFV_1 and HFV_2.