Pixel Mapping on AXI4-Stream Interface - 2.1 English

DisplayPort RX Subsystem LogiCORE IP Product Guide (PG233)
Document ID
PG233
Release Date
2023-05-25
Version
2.1 English

By default, the pixel mode is equal to the lane count during subsystem generation. You can override pixel width dynamically. For example, if the driver selects a two pixel mode as default, you can change the pixel mode to 1.

  • For pixel mode of 1, valid pixels are available only in pixel 0 position.
  • For pixel mode of 2, valid pixels are available only in pixel 0 and pixel 1 position.
  • For pixel mode of 4, valid pixels are available only in pixel 0, pixel 1, pixel 2, and pixel 3 position.

The data width of the AXI4-Stream interface depends on different parameters of the core.

Pixel_Width = MAX_BPC x 3
Interface Width = Pixel Width x LANE_COUNT

For example, if the system is generated using four lanes with MAX_BPC of 16, the data width of the AXI4-Stream interface is 16 × 4 × 3 = 192. For more detailed information on the mapping of the color components on the AXI4-Stream interface, see the Data Format section in the AXI4-Stream Video IP and System Design Guide (UG934).

The following table shows pixel mapping on AXI4-Stream for all the video sampling modes (4:4:4, 4:2:2, Y-only). Implementation of 4:2:2 and Y-only sampling modes pixel mapping is different from the guidelines defined in the AXI4-Stream Video IP and System Design Guide (UG934).

Table 1. Pixel Mapping Examples on AXI4-Stream Interface
MAX_BPC LANES Pixel Width Interface Width Video BPC Pixel 3 Pixel 2 Pixel 1 Pixel 0
16 4 48 192 16 191:176 175:160 159:144 143:128 127:112 111:96 95:80 79:64 63:48 47:32 31:16 15:0
2 96 – – – – – – 95:80 79:64 63:48 47:32 31:16 15:0
1 48 – – – – – – – – – 47:32 31:16 15:0
12 4 36 144 12 143:132 131:120 119:108 107:96 95:84 83:72 71:60 59:48 47:36 35:24 23:12 11:0
2 72 – – – – – – 71:60 59:48 47:36 35:24 23:12 11:0
1 36 – – – – – – – – – 35:24 23:12 11:0
10 4 30 120 10 119:110 109:100 99:90 89:80 79:70 69:60 59:50 49:40 39:30 29:20 19:10 9:0
2 60 – – – – – – 59:50 49:40 39:30 29:20 19:10 9:0
1 30 – – – – – – – – – 29:20 19:10 9:0
8 4 24 96 8 95:88 87:80 79:72 71:64 63:56 55:48 47:40 39:32 31:24 23:16 15:8 7:0
2 48 – – – – – – 47:40 39:32 31:24 23:16 15:8 7:0
1 24 – – – – – – – – – 23:16 15:8 7:0
16 4 48 192 12 191:180 175:164 159:148 143:132 127:116 111:100 95:84 79:68 63:52 47:36 31:20 15:4
2 96 – – – – – – 95:84 79:68 63:52 47:36 31:20 15:4
1 48 – – – – – – – – – 47:36 31:20 15:4
12 4 36 144 10 143:134 131:122 119:110 107:98 95:86 83:74 71:62 59:50 47:38 35:26 23:14 11:2
2 72 – – – – – – 71:62 59:50 47:38 35:26 23:14 11:2
1 36 – – – – – – – – – 35:26 23:14 11:2
10 4 30 120 8 119:112 109:102 99:92 89:82 79:72 69:62 59:52 49:42 39:32 29:22 19:12 9:2
2 60 – – – – – – 59:52 49:42 39:32 29:22 19:12 9:2
1 30 – – – – – – – – – 29:22 19:12 9:2
8 4 24 96 6 95:90 87:82 79:74 71:66 63:58 55:50 47:42 39:34 31:26 23:18 15:10 7:2
2 48 – – – – – – 47:42 39:34 31:26 23:18 15:10 7:2
1 24 – – – – – – – – – 23:18 15:10 7:2
16 4 48 192 10 191:182 175:166 159:150 143:134 127:118 111:102 95:86 79:70 63:54 47:38 31:22 15:6
2 96 – – – – – – 95:86 79:70 63:54 47:38 31:22 15:6
1 48 – – – – – – – – – 47:38 31:22 15:6
12 4 36 144 8 143:136 131:124 119:112 107:100 95:88 83:76 71:64 59:52 47:40 35:28 23:16 11:4
2 72 – – – – – – 71:64 59:52 47:40 35:28 23:16 11:4
1 36 – – – – – – – – – 35:28 23:16 11:4
10 4 30 120 6 119:114 109:104 99:94 89:84 79:74 69:64 59:54 49:44 39:34 29:24 19:14 9:4
2 60 – – – – – – 59:54 49:44 39:34 29:24 19:14 9:4
1 30 – – – – – – – – – 29:24 19:14 9:4
16 4 48 192 8 191:184 175:168 159:152 143:136 127:120 111:104 95:88 79:72 63:56 47:40 31:24 15:8
2 96 – – – – – – 95:88 79:72 63:56 47:40 31:24 15:8
1 48 – – – – – – – – – 47:40 31:24 15:8
12 4 36 144 6 143:138 131:126 119:114 107:102 95:90 83:78 71:66 59:54 47:42 35:30 23:18 11:6
2 72 – – – – – – 71:66 59:54 47:42 35:30 23:18 11:6
1 36 – – – – – – – – – 35:30 23:18 11:6
16 4 48 192 191:186 175:170 159:154 143:138 127:122 111:106 95:90 79:74 63:58 47:42 31:26 15:10
2 96 – – – – – – 95:90 79:74 63:58 47:42 31:26 15:10
1 48 – – – – – – – – – 47:42 31:26 15:10
  1. The padding bits are zeros.

The following table shows the color component mapping for different video sampling modes for the AXI4-Stream pixel mapping shown in the previous table. The 422 and Y-only sampling modes are shown to highlight the difference between video sampling mode mappings. In the following table, MAX_BPC = 16, LANES = 4, and Video BPC = 16.

Table 2. Color Component Mapping for Different Video Sampling Rates
Pixel Width Interface Width Video Sampling Mode Pixel 3 Pixel 2 Pixel 1 Pixel 0
48 192 444 191:176 175:160 159:144 143:128 127:112 111:96 95:80 79:64 63:48 47:32 31:16 15:0]
32 128 422

V2

[191:176]

Y3

[175:160]

 –

U2

[143:128]

Y2

[127:112]

 –

V0

[95:80]

Y1

[79:64]

 –

U0

[47:32]

Y0

[31:16]

 –
16 64

Y-

only

Y2

[191:176]

 – –

Y2

[143:128]

 – –

Y1

[95:80]

 – –

Y0

[47:32]

 – –

The following table shows the pixel mapping examples on the AXI4-Stream interface that are compliant with the guidelines defined in the AXI4-Stream Video IP and System Design Guide (UG934).

Table 3. Pixel Mapping Examples on AXI4-Stream Interface (UG934-Compliant)
MAX_BPC LANES Pixel Width Interface Width Video BPC Video Sampling Mode Pixel 3 Pixel 2 Pixel 1 Pixel 0
8 4 24 96 8 444 95:88 87:80 79:72 71:64 63:56 55:48 47:40 39:32 31:24 23:16 15:8 7:0
16 64 8 422 63:56 55:48 55:48 47:40 39:32   31:24 23:16 23:16 15:8 7:0 7:0
8 32 8 Y-Only 31:24 31:24 31:24 23:16 23:16 23:16 15:8 15:8 15:8 7:0 7:0 7:0
2 24 48 8 444 – – – – – – 47:40 39:32 31:24 23:16 15:8 7:0
16 32 8 422 – – – – – – 31:24 23:16 15:8 15:8 7:0 7:0
8 16 8 Y-Only – –   – –   15:8 15:8 15:8 7:0 7:0 7:0
1 24 24 8 444 – – – – – – – – – 23:16 15:8 7:0
16 16 8 422 – –   – – – – – 15:8 7:0 7:0
8 8 8 Y-Only –     – – – – – – 7:0 7:0 7:0
10 4 30 120 8 444 119:112 109:102 99:92 89:82 79:72 69:62 59:52 49:42 39:32 29:22 19:12 9:2
20 80 8 422 79:72 69:62 69:62 59:52 49:42 49:42 39:32 29:22 29:22 19:12 9:2 9:2
10 40 8 Y-Only 39:32 39:32 39:32 29:22 29:22 29:22 19:12 19:12 19:12 7:0 7:0 7:0
2 30 60 8 444 – – – – – – 59:52 49:42 39:32 29:22 19:12 9:2
20 40 8 422 – – – – – – 39:32 29:22 29:22 19:12 9:2 9:2
10 20 8 Y-Only – –       19:12 19:12 19:12 7:0 7:0 7:0
1 30 30 8 444 – – – – – – – – – 29:22 19:12 9:2
20 20 8 422 – –   – –   – – – 19:12 9:2 9:2
10 10 8 Y-Only             7:0 7:0 7:0
12 4 36 144 8 444 143:136 131:124 119:112 107:100 95:88 83:76 71:64 59:52 47:40 35:28 23:16 11:4
24 96 8 422 95:88 83:76 83:76 71:64 59:52 59:52 47:40 35:28 35:28 23:16 11:4 11:4
12 48 8 Y-Only 47:40 47:40 47:40 35:28     23:16     7:0 7:0 7:0
2 36 72 8 444 – – – – – – 71:64 59:52 47:40 35:28 23:16 11:4
24 48 8 422 – –   – –   47:40 35:28 35:28 23:16 11:4 11:4
12 24 8 Y-Only – – –     23:16     7:0 7:0 7:0
1 36 36 8 444 – – – – – – – – – 35:28 23:16 11:4
24 24 8 422 – –   – –   – – – 23:16 11:4 11:4
12 12 8 Y-Only – –   –     –     7:0 7:0 7:0
16 4 48 192 8 444 191:184 175:168 159:152 143:136 127:120 111:104 95:88 79:72 63:56 47:40 31:24 15:8
32 128 8 422 127:120 111:104 111:104 95:88 79:72 79:72 63:56 47:40   31:24 15:8 15:8
16 64 8 Y-Only 63:56 63:56 63:56 47:40 47:40 47:40 31:24 31:24 31:24 7:0 7:0 7:0
2 48 96 8 444 – – – – – – 95:88 79:72 63:56 47:40 31:24 15:8
32 64 8 422 – – – – – – 63:56 47:40 47:40 31:24 15:8 15:8
16 32 8 Y-Only – – –     31:24 31:24 31:24 7:0 7:0 7:0
1 48 48 8 444 – – – – – – – – – 47:40 31:24 15:8
32 32 8 422 – – – – – – – – – 31:24 15:8 15:8
16 16 8 Y-Only –     – – – – – – 15:8 15:8 15:8