Several small improvements

README.md

@@ -32,3 +32,13 @@ and
       vcsm_free(state.lens_shading);
 ```
 when finished.
+
+ls_table.txt is a comma separated file for easy visualization with Gnuplot. For a colored plot of all samples:
+```
+set palette defined (0 "red", 1 "yellow", 2 "magenta", 3 "blue")
+splot "ls_table.txt" using 1:2:3:4 w p ps 0.75 pt 7 lc palette z notitle
+```
+Single sample plot ($4==0 => red):
+```
+splot "ls_table.txt" using 1:2:($4==0?$3:1/0)
+```

lens_shading_analyse.c

@@ -125,7 +125,7 @@ uint16_t black_level_correct(uint16_t raw_pixel, unsigned int black_level, unsig
 int main(int argc, char *argv[])
 {
 	int in = 0;
-	FILE *out, *header;
+	FILE *out, *header, *table;
 	int i, x, y;
 	uint16_t *out_buf[NUM_CHANNELS];
 	void *mmap_buf;
@@ -134,6 +134,7 @@ int main(int argc, char *argv[])
 	int bayer_order;
 	struct brcm_raw_header *hdr;
 	int width, height, stride;
+	int grid_width, grid_height;
 	int single_channel_width, single_channel_height;
 	unsigned int black_level = 16;
 
@@ -208,6 +209,10 @@ int main(int argc, char *argv[])
 	height = hdr->height;
 	single_channel_width = width/2;
 	single_channel_height = height/2;
+	grid_width = single_channel_width / 32 + (single_channel_width % 32 == 0 ? 0 : 1);
+	grid_height = single_channel_height / 32 + (single_channel_height % 32 == 0 ? 0 : 1);
+	printf("Grid size: %d x %d\n", grid_width, grid_height);
+
 	//Stride computed via same formula as the firmware uses.
 	stride = (((((width + hdr->padding_right)*5)+3)>>2) + 31)&(~31);
 
@@ -260,6 +265,7 @@ int main(int argc, char *argv[])
 	printf("Save data. Bayer order is %d\n", bayer_order);
 
 	header = fopen("ls_table.h", "wb");
+	table = fopen("ls_table.txt", "wb");
 	fprintf(header, "uint8_t ls_grid[] = {\n");
 	for (i=0; i<NUM_CHANNELS; i++)
 	{
@@ -321,6 +327,7 @@ int main(int argc, char *argv[])
 				else if (gain < 32)
 					gain = 32;	//Clip at x1.0
 				fprintf(header, "%d, ", gain );
+				fprintf(table, "%d %d %d %d\n", x, y, gain, i );
 			}
 			//Compute edge value from the very edge 2 pixels.
 			{
@@ -331,14 +338,15 @@ int main(int argc, char *argv[])
 				else if (gain < 32)
 					gain = 32;	//Clip at x1.0
 				fprintf(header, "%d,\n", gain );
+				fprintf(table, "%d %d %d %d\n", x, y, gain, i );
 			}
 		}
 
 	}
 	fprintf(header, "};\n");
 	fprintf(header, "uint32_t ref_transform = %u;\n", hdr->transform);
-	fprintf(header, "uint32_t grid_width = %u;\n", (single_channel_width>>5)+1);
-	fprintf(header, "uint32_t grid_height = %u;\n", (single_channel_height>>5)+1);
+	fprintf(header, "uint32_t grid_width = %u;\n", grid_width);
+	fprintf(header, "uint32_t grid_height = %u;\n", grid_height);
 
 	for (i=0; i<NUM_CHANNELS; i++)
 	{