add support for .tga output to mudraw

SumatraPDF's testsuite uses Targa images as output because they're
compressed while still far easier to compare than PNG and have better
tool support than PCL/PWG.

4 files changed, 99 insertions, 3 deletions

diff --git a/include/mupdf/fitz.h b/include/mupdf/fitz.h
index 6cc13efe..00458e8c 100644
--- a/include/mupdf/fitz.h
+++ b/include/mupdf/fitz.h
@@ -54,5 +54,6 @@
 #include "mupdf/fitz/output-pwg.h"
 #include "mupdf/fitz/output-pcl.h"
 #include "mupdf/fitz/output-svg.h"
+#include "mupdf/fitz/output-tga.h"
 
 #endif
diff --git a/include/mupdf/fitz/output-tga.h b/include/mupdf/fitz/output-tga.h
new file mode 100644
index 00000000..316eb182
--- /dev/null
+++ b/include/mupdf/fitz/output-tga.h
@@ -0,0 +1,10 @@
+#ifndef MUPDF_FITZ_OUTPUT_TGA_H
+#define MUPDF_FITZ_OUTPUT_TGA_H
+
+#include "mupdf/fitz/system.h"
+#include "mupdf/fitz/context.h"
+#include "mupdf/fitz/pixmap.h"
+
+void fz_write_tga(fz_context *ctx, fz_pixmap *pixmap, const char *filename, int savealpha);
+
+#endif
diff --git a/source/fitz/pixmap.c b/source/fitz/pixmap.c
index 8b3ac6a6..8692a468 100644
--- a/source/fitz/pixmap.c
+++ b/source/fitz/pixmap.c
@@ -841,6 +841,85 @@ fz_image_as_png(fz_context *ctx, fz_image *image, int w, int h)
 	return buf;
 }
 
+/*
+ * Write pixmap to TGA file (with or without alpha channel)
+ */
+
+static inline void tga_put_pixel(unsigned char *data, int n, int is_bgr, fz_output *out)
+{
+	if (n >= 3 && !is_bgr)
+	{
+		fz_putc(out, data[2]);
+		fz_putc(out, data[1]);
+		fz_putc(out, data[0]);
+		if (n == 4)
+			fz_putc(out, data[3]);
+		return;
+	}
+	if (n == 2)
+	{
+		fz_putc(out, data[0]);
+		fz_putc(out, data[0]);
+	}
+	fz_write(out, data, n);
+}
+
+void
+fz_write_tga(fz_context *ctx, fz_pixmap *pixmap, const char *filename, int savealpha)
+{
+	fz_output *out;
+	unsigned char head[18];
+	int n = pixmap->n;
+	int d = savealpha || n == 1 ? n : n - 1;
+	int is_bgr = pixmap->colorspace == fz_device_bgr(ctx);
+	int k;
+
+	if (pixmap->colorspace && pixmap->colorspace != fz_device_gray(ctx) &&
+		pixmap->colorspace != fz_device_rgb(ctx) && pixmap->colorspace != fz_device_bgr(ctx))
+	{
+		fz_throw(ctx, FZ_ERROR_GENERIC, "pixmap must be grayscale or rgb to write as tga");
+	}
+
+	out = fz_new_output_to_filename(ctx, filename);
+
+	memset(head, 0, sizeof(head));
+	head[2] = n == 4 ? 10 : 11;
+	head[12] = pixmap->w & 0xFF; head[13] = (pixmap->w >> 8) & 0xFF;
+	head[14] = pixmap->h & 0xFF; head[15] = (pixmap->h >> 8) & 0xFF;
+	head[16] = d * 8;
+	head[17] = savealpha && n > 1 ? 8 : 0;
+	if (savealpha && d == 2)
+		head[16] = 32;
+
+	fz_write(out, head, sizeof(head));
+	for (k = 1; k <= pixmap->h; k++)
+	{
+		int i, j;
+		unsigned char *line = pixmap->samples + pixmap->w * n * (pixmap->h - k);
+		for (i = 0, j = 1; i < pixmap->w; i += j, j = 1)
+		{
+			for (; i + j < pixmap->w && j < 128 && !memcmp(line + i * n, line + (i + j) * n, d); j++);
+			if (j > 1)
+			{
+				fz_putc(out, j - 1 + 128);
+				tga_put_pixel(line + i * n, d, is_bgr, out);
+			}
+			else
+			{
+				for (; i + j < pixmap->w && j <= 128 && memcmp(line + (i + j - 1) * n, line + (i + j) * n, d) != 0; j++);
+				if (i + j < pixmap->w || j > 128)
+					j--;
+				fz_putc(out, j - 1);
+				for (; j > 0; j--, i++)
+					tga_put_pixel(line + i * n, d, is_bgr, out);
+			}
+		}
+	}
+	fz_write(out, "\0\0\0\0\0\0\0\0TRUEVISION-XFILE.\0", 26);
+
+	fz_close_output(out);
+}
+
 unsigned int
 fz_pixmap_size(fz_context *ctx, fz_pixmap * pix)
 {
diff --git a/source/tools/mudraw.c b/source/tools/mudraw.c
index 81222993..c95be5e3 100644
--- a/source/tools/mudraw.c
+++ b/source/tools/mudraw.c
@@ -14,7 +14,7 @@
 
 enum { TEXT_PLAIN = 1, TEXT_HTML = 2, TEXT_XML = 3 };
 
-enum { OUT_PNG, OUT_PPM, OUT_PNM, OUT_PAM, OUT_PGM, OUT_PBM, OUT_SVG, OUT_PWG, OUT_PCL, OUT_PDF };
+enum { OUT_PNG, OUT_PPM, OUT_PNM, OUT_PAM, OUT_PGM, OUT_PBM, OUT_SVG, OUT_PWG, OUT_PCL, OUT_PDF, OUT_TGA };
 
 enum { CS_INVALID, CS_UNSET, CS_MONO, CS_GRAY, CS_GRAYALPHA, CS_RGB, CS_RGBA };
 
@@ -36,6 +36,7 @@ static const suffix_t suffix_table[] =
 	{ ".pwg", OUT_PWG },
 	{ ".pcl", OUT_PCL },
 	{ ".pdf", OUT_PDF },
+	{ ".tga", OUT_TGA },
 };
 
 typedef struct
@@ -77,7 +78,8 @@ static const format_cs_table_t format_cs_table[] =
 	{ OUT_SVG, CS_RGB, { CS_RGB } },
 	{ OUT_PWG, CS_RGB, { CS_MONO, CS_GRAY, CS_RGB } },
 	{ OUT_PCL, CS_MONO, { CS_MONO } },
-	{ OUT_PDF, CS_RGB, { CS_RGB } }
+	{ OUT_PDF, CS_RGB, { CS_RGB } },
+	{ OUT_TGA, CS_RGB, { CS_GRAY, CS_GRAYALPHA, CS_RGB, CS_RGBA } },
 };
 
 /*
@@ -183,7 +185,7 @@ static void usage(void)
 		"usage: mudraw [options] input [pages]\n"
 		"\t-o -\toutput filename (%%d for page number)\n"
 		"\t-F -\toutput format (if no -F, -o will be examined)\n"
-		"\t\tsupported formats: pgm, ppm, pam, png, pbm\n"
+		"\t\tsupported formats: pgm, ppm, pam, png, pbm, tga\n"
 		"\t-p -\tpassword\n"
 		"\t-r -\tresolution in dpi (default: 72)\n"
 		"\t-w -\twidth (in pixels) (maximum width if -r is specified)\n"
@@ -758,6 +760,10 @@ static void drawpage(fz_context *ctx, fz_document *doc, int pagenum)
 						fz_write_pbm(ctx, bit, filename_buf);
 						fz_drop_bitmap(ctx, bit);
 					}
+					else if (output_format == OUT_TGA)
+					{
+						fz_write_tga(ctx, pix, filename_buf, savealpha);
+					}
 				}
 				ctm.f -= drawheight;
 			}