Rewrite `ImageOut`, remove channel ID in filename

README.md

@@ -87,7 +87,8 @@ Generated images are outputted in PNG and are 24 bit RGB for all image types apa
 Image names are `audiofile-x.png`, where `x` is:
 
  - `r` for raw images
- - Sensor ID (`1`, `2`, `3A`, `3B`, `4`, `5`) for channel A|B images
+ - `a` channel A images
+ - `b` channel B images
  - `p` for a paletted image
  - `t` for temperature calibrated images
  - `m` for MCIR images

common.h

@@ -32,6 +32,7 @@ typedef struct {
 typedef struct {
 	float *prow[MAX_HEIGHT]; // Row buffers
 	int nrow; // Number of rows
+	int zenith;
 	int chA, chB; // ID of each channel
 	char name[256]; // Stripped filename
 	char *palette; // Filename of palette
@@ -45,4 +46,22 @@ typedef struct {
 	int   realtime; // Realtime decoding
 	char *filename; // Output filename
 	char *palette; // Filename of palette
-} options_t;
+} options_t;
+
+enum imagetypes {
+	Raw_Image='r',
+	MCIR='m',
+	Palleted='p',
+	Temperature='t',
+	Channel_A='a',
+	Channel_B='b',
+	Distribution='d'
+};
+enum effects {
+	Crop_Telemetry='t',
+	Histogram_Equalise='h',
+	Denoise='d',
+	Precipitation_Overlay='p',
+	Flip_Image='f',
+	Linear_Equalise='l'
+};

main.c

@@ -54,8 +54,6 @@ extern void flipImage(image_t *img, int width, int offset);
 extern char GviPalette[256*3];
 extern char TempPalette[256*3];
 
-// Row where the satellite is closest to the observer
-int zenith = 0;
 // Audio file
 static SNDFILE *audioFile;
 // Number of channels in audio file
@@ -174,7 +172,7 @@ static int processAudio(char *filename, options_t *opts){
 			img.prow[img.nrow] = (float *) malloc(sizeof(float) * 2150);
 
 			// Write into memory and break the loop when there are no more samples to read
-			if (getpixelrow(img.prow[img.nrow], img.nrow, &zenith, (img.nrow == 0)) == 0)
+			if (getpixelrow(img.prow[img.nrow], img.nrow, &img.zenith, (img.nrow == 0)) == 0)
 				break;
 
 			if(opts->realtime) pushRow(img.prow[img.nrow], IMG_WIDTH);
@@ -193,9 +191,9 @@ static int processAudio(char *filename, options_t *opts){
 
 	// Fallback for detecting the zenith
 	// TODO: encode metadata in raw images
-	if(opts->map != NULL && opts->map[0] != '\0' && zenith == 0){
+	if(opts->map != NULL && opts->map[0] != '\0' && img.zenith == 0){
 		fprintf(stderr, "Guessing zenith in image, map will most likely be misaligned.\n");
-		zenith = img.nrow / 2;
+		img.zenith = img.nrow / 2;
 	}
 
 	// Calibrate
@@ -205,67 +203,67 @@ static int processAudio(char *filename, options_t *opts){
 	printf("Channel B: %s (%s)\n", ch.id[img.chB], ch.name[img.chB]);
 
 	// Denoise
-	if(CONTAINS(opts->effects, 'd')){
+	if(CONTAINS(opts->effects, Denoise)){
 		denoise(img.prow, img.nrow, CHA_OFFSET, CH_WIDTH);
 		denoise(img.prow, img.nrow, CHB_OFFSET, CH_WIDTH);
 	}
 
 	// Flip, for southbound passes
-	if(CONTAINS(opts->effects, 'f')){
+	if(CONTAINS(opts->effects, Flip_Image)){
 		flipImage(&img, CH_WIDTH, CHA_OFFSET);
 		flipImage(&img, CH_WIDTH, CHB_OFFSET);
 	}
 
 	// Temperature
-	if (CONTAINS(opts->type, 't') && img.chB >= 4) {
+	if (CONTAINS(opts->type, Temperature) && img.chB >= 4) {
 		temperature(opts, &img, CHB_OFFSET, CH_WIDTH);
-		ImageOut(opts, &img, CHB_OFFSET, CH_WIDTH, "Temperature", "t", (char *)TempPalette);
+		ImageOut(opts, &img, CHB_OFFSET, CH_WIDTH, "Temperature", Temperature, (char *)TempPalette);
 	}
 
 	// MCIR
-	if (CONTAINS(opts->type, 'm'))
-		ImageOut(opts, &img, CHA_OFFSET, CH_WIDTH, "MCIR", "m", NULL);
+	if (CONTAINS(opts->type, MCIR))
+		ImageOut(opts, &img, CHA_OFFSET, CH_WIDTH, "MCIR", MCIR, NULL);
 
 	// Linear equalise
-	if(CONTAINS(opts->effects, 'l')){
+	if(CONTAINS(opts->effects, Linear_Equalise)){
 		linearEnhance(img.prow, img.nrow, CHA_OFFSET, CH_WIDTH);
 		linearEnhance(img.prow, img.nrow, CHB_OFFSET, CH_WIDTH);
 	}
 
 	// Histogram equalise
-	if(CONTAINS(opts->effects, 'h')){
+	if(CONTAINS(opts->effects, Histogram_Equalise)){
 		histogramEqualise(img.prow, img.nrow, CHA_OFFSET, CH_WIDTH);
 		histogramEqualise(img.prow, img.nrow, CHB_OFFSET, CH_WIDTH);
 	}
 
 	// Raw image
-	if (CONTAINS(opts->type, 'r')) {
+	if (CONTAINS(opts->type, Raw_Image)) {
 		sprintf(desc, "%s (%s) & %s (%s)", ch.id[img.chA], ch.name[img.chA], ch.id[img.chB], ch.name[img.chB]);
-		ImageOut(opts, &img, 0, IMG_WIDTH, desc, "r", NULL);
+		ImageOut(opts, &img, 0, IMG_WIDTH, desc, Raw_Image, NULL);
 	}
 
 	// Palette image
-	if (CONTAINS(opts->type, 'p')) {
+	if (CONTAINS(opts->type, Palleted)) {
 		img.palette = opts->palette;
 		strcpy(desc, "Palette composite");
-		ImageOut(opts, &img, 0, 909, desc, "p", NULL);
+		ImageOut(opts, &img, CHA_OFFSET, 909, desc, Palleted, NULL);
 	}
 
 	// Channel A
-	if (CONTAINS(opts->type, 'a')) {
+	if (CONTAINS(opts->type, Channel_A)) {
 		sprintf(desc, "%s (%s)", ch.id[img.chA], ch.name[img.chA]);
-		ImageOut(opts, &img, CHA_OFFSET, CH_WIDTH, desc, ch.id[img.chA], NULL);
+		ImageOut(opts, &img, CHA_OFFSET, CH_WIDTH, desc, Channel_A, NULL);
 	}
 
 	// Channel B
-	if (CONTAINS(opts->type, 'b')) {
+	if (CONTAINS(opts->type, Channel_B)) {
 		sprintf(desc, "%s (%s)", ch.id[img.chB], ch.name[img.chB]);
-		ImageOut(opts, &img, CHB_OFFSET, CH_WIDTH, desc, ch.id[img.chB], NULL);
+		ImageOut(opts, &img, CHB_OFFSET, CH_WIDTH, desc, Channel_B, NULL);
 	}
 
 	// Value distribution image
-	if (CONTAINS(opts->type, 'd'))
-		distrib(opts, &img, "d");
+	if (CONTAINS(opts->type, Distribution))
+		distrib(opts, &img, Distribution);
 
 	return 1;
 }

pngio.c

@@ -26,7 +26,6 @@
 #include "common.h"
 #include "offsets.h"
 
-extern int zenith;
 extern char PrecipPalette[256*3];
 extern rgb_t applyPalette(char *palette, int val);
 extern rgb_t RGBcomposite(rgb_t top, float top_a, rgb_t bottom, float bottom_a);
@@ -193,7 +192,7 @@ int readRawImage(char *filename, float **prow, int *nrow) {
 	return 1;
 }
 
-int readPalette(char *filename, rgb_t **crow) {
+int readPalette(char *filename, rgb_t **pixels) {
 	FILE *fp = fopen(filename, "r");
 	if(!fp) {
 		fprintf(stderr, "Cannot open %s\n", filename);
@@ -222,7 +221,7 @@ int readPalette(char *filename, rgb_t **crow) {
 		fprintf(stderr, "Palette must be 8 bit color.\n");
 		return 0;
 	}else if(color_type != PNG_COLOR_TYPE_RGBA){
-		fprintf(stderr, "Palette must be RGB.\n");
+		fprintf(stderr, "Palette must be RGBA.\n");
 		return 0;
 	}
 
@@ -241,10 +240,10 @@ int readPalette(char *filename, rgb_t **crow) {
 
 	// Put into crow
 	for(int y = 0; y < height; y++) {
-		crow[y] = (rgb_t *) malloc(sizeof(rgb_t) * width);
+		pixels[y] = (rgb_t *) malloc(sizeof(rgb_t) * width);
 
 		for(int x = 0; x < width; x++)
-			crow[y][x] = (rgb_t){
+			pixels[y][x] = (rgb_t){
 				PNGrows[y][x*4],
 				PNGrows[y][x*4 + 1], 
 				PNGrows[y][x*4 + 2]
@@ -254,35 +253,92 @@ int readPalette(char *filename, rgb_t **crow) {
 	return 1;
 }
 
-png_text meta[] = {
-	{PNG_TEXT_COMPRESSION_NONE, "Software", VERSION},
-	{PNG_TEXT_COMPRESSION_NONE, "Channel", "Unknown", 7},
-	{PNG_TEXT_COMPRESSION_NONE, "Description", "NOAA satellite image", 20}
-};
+void prow2crow(float **prow, int nrow, char palette, rgb_t **crow){
+	for(int y = 0; y < nrow; y++){
+		crow[y] = (rgb_t *) malloc(sizeof(rgb_t) * IMG_WIDTH);
 
-int ImageOut(options_t *opts, image_t *img, int offset, int width, char *desc, char *chid, char *palette){
-	char outName[384];
+		for(int x = 0; x < IMG_WIDTH; x++){
+			if(palette == NULL)
+				crow[y][x].r = crow[y][x].g = crow[y][x].b = prow[y][x];
+			else
+				crow[y][x] = applyPalette(palette, prow[y][x]);
+		}
+	}
+}
+
+int applyUserPalette(float **prow, int nrow, char *filename, rgb_t **crow){
+	rgb_t *pal_row[256];
+	if(!readPalette(filename, pal_row)){
+		fprintf(stderr, "Could not read palette");
+		return 0;
+	}
+
+	for(int y = 0; y < nrow; y++){
+		for(int x = 0; x < CH_WIDTH; x++){
+			int cha = prow[y][x + CHA_OFFSET];
+			int cbb = prow[y][x + CHB_OFFSET];
+			crow[y][x + CHA_OFFSET] = pal_row[cbb][cha];
+		}
+	}
+	
+	return 1;
+}
+
+int ImageOut(options_t *opts, image_t *img, int offset, int width, char *desc, char chid, char *palette){
+	char outName[512];
 	if(opts->filename == NULL || opts->filename[0] == '\0'){
-		sprintf(outName, "%s/%s-%s.png", opts->path, img->name, chid);
+		sprintf(outName, "%s/%s-%c.png", opts->path, img->name, chid);
 	}else{
-		sprintf(outName, "%s/%s", opts->path, opts -> filename);
+		sprintf(outName, "%s/%s", opts->path, opts->filename);
 	}
 
-	meta[1].text = desc;
-	meta[1].text_length = sizeof(desc);
-
-	FILE *pngfile;
+	png_text meta[] = {
+		{PNG_TEXT_COMPRESSION_NONE, "Software", VERSION},
+		{PNG_TEXT_COMPRESSION_NONE, "Channel", desc, sizeof(desc)},
+		{PNG_TEXT_COMPRESSION_NONE, "Description", "NOAA satellite image", 20}
+	};
+
+	// Parse image type
+	int greyscale = 1;
+	switch (chid){
+		case Palleted:
+			greyscale = 0;
+			break;
+		case Temperature:
+			greyscale = 0;
+			break;
+		case MCIR:
+			greyscale = 0;
+			break;
+		case Raw_Image: break;
+		case Channel_A: break;
+		case Channel_B: break;
+	}
 
-	// Reduce the width of the image to componsate for the missing telemetry
-	int fc = (chid[0] == 'c');
-	int greyscale = 0;
-	int skiptele = 0;
-	int imgpalette = (chid[0] == 'p');
-	if(opts->effects != NULL && CONTAINS(opts->effects, 't')){
-		width -= TOTAL_TELE;
-		skiptele = 1;
+	// Parse effects
+	int crop_telemetry = 0;
+	for(int i = 0; i < strlen(opts->effects); i++){
+		switch (opts->effects[i]) {
+			case Crop_Telemetry:
+				width -= TOTAL_TELE;
+				offset += SYNC_WIDTH + SPC_WIDTH;
+				crop_telemetry = 1;
+				break;
+			case Precipitation_Overlay:
+				greyscale = 0;
+				break;
+			case Flip_Image: break;
+			case Denoise: break;
+			case Histogram_Equalise: break;
+			case Linear_Equalise: break;
+			default:
+				fprintf(stderr, "NOTICE: Unrecognised effect, \"%c\"\n", opts->effects[i]);
+				break;
+		}
 	}
 
+	FILE *pngfile;
+
 	// Create writer
 	png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
 	if (!png_ptr) {
@@ -297,9 +353,7 @@ int ImageOut(options_t *opts, image_t *img, int offset, int width, char *desc, c
 		return 0;
 	}
 
-	if(palette == NULL && !CONTAINS(opts->effects, 'p') && !fc && opts->map[0] == '\0' && chid[0] != 'm' && !imgpalette){
-		greyscale = 1;
-
+	if(greyscale){
 		// Greyscale image
 		png_set_IHDR(png_ptr, info_ptr, width, img->nrow,
 					 8, PNG_COLOR_TYPE_GRAY, PNG_INTERLACE_NONE,
@@ -323,52 +377,39 @@ int ImageOut(options_t *opts, image_t *img, int offset, int width, char *desc, c
 	png_init_io(png_ptr, pngfile);
 	png_write_info(png_ptr, info_ptr);
 
-	// Move prow into crow, crow ~ color rows
+	// Move prow into crow, crow ~ color rows, if required
 	rgb_t *crow[img->nrow];
-	if(!greyscale && !fc){
-		for(int y = 0; y < img->nrow; y++){
-			crow[y] = (rgb_t *) malloc(sizeof(rgb_t) * IMG_WIDTH);
+	if(!greyscale)
+		prow2crow(img->prow, img->nrow, palette, crow);
 
-			for(int x = 0; x < IMG_WIDTH; x++){
-				if(palette == NULL)
-					crow[y][x].r = crow[y][x].g = crow[y][x].b = img->prow[y][x];
-				else
-					crow[y][x] = applyPalette(palette, img->prow[y][x]);
-			}
-		}
-	}
+	// Apply a user provided color palette
+	if(CONTAINS(opts->type, Palleted))
+		applyUserPalette(img->prow, img->nrow, opts->palette, crow);
 
 	// Precipitation
-	// TODO: use temperature calibration
-	if(CONTAINS(opts->effects, 'p')){
+	// TODO: use temperature calibration, and a better palette
+	if(CONTAINS(opts->effects, Precipitation_Overlay)){
 		for(int y = 0; y < img->nrow; y++){
 			for(int x = 0; x < CH_WIDTH; x++){
 				if(img->prow[y][x + CHB_OFFSET] > 191)
-					crow[y][x + CHB_OFFSET] = applyPalette(PrecipPalette, img->prow[y][x + CHB_OFFSET]);
+					crow[y][x + CHB_OFFSET] = crow[y][x + CHA_OFFSET] = applyPalette(PrecipPalette, img->prow[y][x + CHB_OFFSET]);
 			}
 		}
 	}
 
 	// Map stuff
 	if(opts->map != NULL && opts->map[0] != '\0'){
-		if(mapOverlay(opts->map, crow, img->nrow, zenith, (chid[0] == 'm')) == 0){
+		if(!mapOverlay(opts->map, crow, img->nrow, img->zenith, CONTAINS(opts->type, MCIR))){
 			fprintf(stderr, "Skipping MCIR generation.\n");
 			return 0;
 		}
-	}else if(chid[0] == 'm'){
+	}else if(CONTAINS(opts->type, MCIR)){
 		fprintf(stderr, "Skipping MCIR generation; no map provided.\n");
 		return 0;
 	}
 
 	printf("Writing %s", outName);
 
-	rgb_t *pal_row[256];
-	if(imgpalette){
-		if(!readPalette(img->palette, pal_row)){
-			return 0;
-		}
-	}
-
 	// Build image
 	for (int y = 0; y < img->nrow; y++) {
 		png_color pix[width]; // Color
@@ -376,33 +417,12 @@ int ImageOut(options_t *opts, image_t *img, int offset, int width, char *desc, c
 
 		int skip = 0;
 		for (int x = 0; x < width; x++) {
-			if(skiptele){
-				switch (x) {
-					case 0:
-						skip += SYNC_WIDTH + SPC_WIDTH;
-						break;
-					case CH_WIDTH:
-						skip += TELE_WIDTH + SYNC_WIDTH + SPC_WIDTH;
-						break;
-				}
+			if(crop_telemetry && x == CH_WIDTH){
+				skip += TELE_WIDTH + SYNC_WIDTH + SPC_WIDTH;
 			}
 
 			if(greyscale){
 				mpix[x] = img->prow[y][x + skip + offset];
-			}else if(fc){
-				pix[x] = (png_color){
-					CLIP(img->prow[y][x + CHA_OFFSET], 0, 255),
-					CLIP(img->prow[y][x + CHA_OFFSET], 0, 255),
-					CLIP(img->prow[y][x + CHB_OFFSET], 0, 255)
-				};
-			}else if(imgpalette){
-				int cha = img->prow[y][x + CHA_OFFSET];
-				int cbb = img->prow[y][x + CHB_OFFSET];
-				pix[x] = (png_color){
-					pal_row[cbb][cha].r,
-					pal_row[cbb][cha].g,
-					pal_row[cbb][cha].b
-				};
 			}else{
 				pix[x] = (png_color){
 					crow[y][x + skip + offset].r,
@@ -437,8 +457,11 @@ int initWriter(options_t *opts, image_t *img, int width, int height, char *desc,
 	char outName[384];
 	sprintf(outName, "%s/%s-%s.png", opts->path, img->name, chid);
 
-	meta[1].text = desc;
-	meta[1].text_length = sizeof(desc);
+	png_text meta[] = {
+		{PNG_TEXT_COMPRESSION_NONE, "Software", VERSION},
+		{PNG_TEXT_COMPRESSION_NONE, "Channel", desc, sizeof(desc)},
+		{PNG_TEXT_COMPRESSION_NONE, "Description", "NOAA satellite image", 20}
+	};
 
 	// Create writer
 	rt_png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);