--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/source/fitz/output-psd.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,451 @@
+// Copyright (C) 2004-2021 Artifex Software, Inc.
+//
+// This file is part of MuPDF.
+//
+// MuPDF is free software: you can redistribute it and/or modify it under the
+// terms of the GNU Affero General Public License as published by the Free
+// Software Foundation, either version 3 of the License, or (at your option)
+// any later version.
+//
+// MuPDF is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+// details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with MuPDF. If not, see <https://www.gnu.org/licenses/agpl-3.0.en.html>
+//
+// Alternative licensing terms are available from the licensor.
+// For commercial licensing, see <https://www.artifex.com/> or contact
+// Artifex Software, Inc., 39 Mesa Street, Suite 108A, San Francisco,
+// CA 94129, USA, for further information.
+
+#include "mupdf/fitz.h"
+
+#include <string.h>
+
+void
+fz_save_pixmap_as_psd(fz_context *ctx, fz_pixmap *pixmap, const char *filename)
+{
+	fz_output *out = fz_new_output_with_path(ctx, filename, 0);
+	fz_band_writer *writer = NULL;
+
+	fz_var(writer);
+
+	fz_try(ctx)
+	{
+		writer = fz_new_psd_band_writer(ctx, out);
+		fz_write_header(ctx, writer, pixmap->w, pixmap->h, pixmap->n, pixmap->alpha, pixmap->xres, pixmap->yres, 0, pixmap->colorspace, pixmap->seps);
+		fz_write_band(ctx, writer, pixmap->stride, pixmap->h, pixmap->samples);
+		fz_close_band_writer(ctx, writer);
+		fz_close_output(ctx, out);
+	}
+	fz_always(ctx)
+	{
+		fz_drop_band_writer(ctx, writer);
+		fz_drop_output(ctx, out);
+	}
+	fz_catch(ctx)
+	{
+		fz_rethrow(ctx);
+	}
+}
+
+void
+fz_write_pixmap_as_psd(fz_context *ctx, fz_output *out, const fz_pixmap *pixmap)
+{
+	fz_band_writer *writer;
+
+	if (!out)
+		return;
+
+	writer = fz_new_psd_band_writer(ctx, out);
+
+	fz_try(ctx)
+	{
+		fz_write_header(ctx, writer, pixmap->w, pixmap->h, pixmap->n, pixmap->alpha, pixmap->xres, pixmap->yres, 0, pixmap->colorspace, pixmap->seps);
+		fz_write_band(ctx, writer, pixmap->stride, pixmap->h, pixmap->samples);
+		fz_close_band_writer(ctx, writer);
+	}
+	fz_always(ctx)
+	{
+		fz_drop_band_writer(ctx, writer);
+	}
+	fz_catch(ctx)
+	{
+		fz_rethrow(ctx);
+	}
+}
+
+typedef struct psd_band_writer_s
+{
+	fz_band_writer super;
+	int num_additive;
+} psd_band_writer;
+
+static void
+psd_write_header(fz_context *ctx, fz_band_writer *writer_, fz_colorspace *cs)
+{
+	psd_band_writer *writer = (psd_band_writer *)(void *)writer_;
+	fz_output *out = writer->super.out;
+	int w = writer->super.w;
+	int h = writer->super.h;
+	int s = writer->super.s;
+	int n = writer->super.n;
+	int c = n - writer->super.alpha - s;
+	fz_separations *seps = writer->super.seps;
+	int i;
+	size_t len;
+	static const char psdsig[12] = { '8', 'B', 'P', 'S', 0, 1, 0, 0, 0, 0, 0, 0 };
+	static const char ressig[4] = { '8', 'B', 'I', 'M' };
+	unsigned char *data;
+	size_t size;
+	fz_colorspace *cs_cmyk = cs;
+
+#if FZ_ENABLE_ICC
+	size = fz_buffer_storage(ctx, cs->u.icc.buffer, &data);
+#else
+	size = 0;
+	data = NULL;
+#endif
+
+	if (cs->n != 4)
+		cs_cmyk = fz_device_cmyk(ctx);
+
+	if (!fz_colorspace_is_subtractive(ctx, cs))
+		writer->num_additive = cs->n;
+
+	/* File Header Section */
+	fz_write_data(ctx, out, psdsig, 12);
+	fz_write_int16_be(ctx, out, n);
+	fz_write_int32_be(ctx, out, h);
+	fz_write_int32_be(ctx, out, w);
+	fz_write_int16_be(ctx, out, 8); /* bits per channel */
+
+	switch (c)
+	{
+	case 0:
+	case 1:
+		fz_write_int16_be(ctx, out, 1); /* Greyscale */
+		break;
+	case 3:
+		fz_write_int16_be(ctx, out, 3); /* RGB */
+		break;
+	case 4:
+		fz_write_int16_be(ctx, out, 4); /* CMYK */
+		break;
+	default:
+		fz_write_int16_be(ctx, out, 7); /* Multichannel */
+		break;
+	}
+
+	/* Color Mode Data Section - empty */
+	fz_write_int32_be(ctx, out, 0);
+
+	/* Image Resources Section - Spot Names, Equivalent colors, resolution, ICC Profile */
+	/* Spot names */
+	len = 0;
+	for (i = 0; i < s; i++)
+	{
+		const char *name = fz_separation_name(ctx, seps, i);
+		char text[32];
+		size_t len2;
+		if (name == NULL)
+		{
+			fz_snprintf(text, sizeof text, "Spot%d", i-4);
+			name = text;
+		}
+		len2 = strlen(name);
+		if (len2 > 255)
+			len2 = 255;
+		len += len2 + 1;
+	}
+
+	/* Write the size of all the following resources */
+	fz_write_int32_be(ctx, out,
+			(s ? 12 + ((len + 1)&~1) : 0) +	/* Spot Names */
+			(s ? 12 + (14 * s) : 0) +	/* DisplayInfo */
+			28 +				/* Resolutions */
+			(size ? (size+19)&~1 : 0));	/* ICC Profile */
+
+	/* Spot names */
+	if (s != 0)
+	{
+		fz_write_data(ctx, out, ressig, 4);
+		fz_write_int16_be(ctx, out, 0x03EE);
+		fz_write_int16_be(ctx, out, 0); /* PString */
+		fz_write_int32_be(ctx, out, (len + 1)&~1);
+		for (i = 0; i < s; i++) {
+			size_t len2;
+			const char *name = fz_separation_name(ctx, seps, i);
+			char text[32];
+			if (name == NULL)
+			{
+				fz_snprintf(text, sizeof text, "Spot%d", i-4);
+				name = text;
+			}
+			len2 = strlen(name);
+			if (len2 > 255)
+				len2 = 255;
+			fz_write_byte(ctx, out, (unsigned char)len2);
+			fz_write_data(ctx, out, name, len2);
+		}
+		if (len & 1)
+		{
+			fz_write_byte(ctx, out, 0);
+		}
+
+		/* DisplayInfo - Colors for each spot channel */
+		fz_write_data(ctx, out, ressig, 4);
+		fz_write_int16_be(ctx, out, 0x03EF);
+		fz_write_int16_be(ctx, out, 0); /* PString */
+		fz_write_int32_be(ctx, out, 14 * s); /* Length */
+		for (i = 0; i < s; i++) {
+			float cmyk[4];
+			fz_separation_equivalent(ctx, seps, i, cs_cmyk, cmyk, NULL, fz_default_color_params);
+			fz_write_int16_be(ctx, out, 02); /* CMYK */
+			/* PhotoShop stores all component values as if they were additive. */
+			fz_write_int16_be(ctx, out, 65535 * (1-cmyk[0]));/* Cyan */
+			fz_write_int16_be(ctx, out, 65535 * (1-cmyk[1]));/* Magenta */
+			fz_write_int16_be(ctx, out, 65535 * (1-cmyk[2]));/* Yellow */
+			fz_write_int16_be(ctx, out, 65535 * (1-cmyk[3]));/* Black */
+			fz_write_int16_be(ctx, out, 0); /* Opacity 0 to 100 */
+			fz_write_byte(ctx, out, 2); /* Don't know */
+			fz_write_byte(ctx, out, 0); /* Padding - Always Zero */
+		}
+	}
+
+	/* ICC Profile - (size + 19)&~1 bytes */
+	if (size != 0)
+	{
+		/* Image Resource block */
+		fz_write_data(ctx, out, ressig, 4);
+		fz_write_int16_be(ctx, out, 0x40f); /* ICC Profile */
+		fz_write_data(ctx, out, "\x07Profile", 8); /* Profile name (must be even!) */
+		fz_write_int32_be(ctx, out, (int)size);
+		fz_write_data(ctx, out, data, size); /* Actual data */
+		if (size & 1)
+			fz_write_byte(ctx, out, 0); /* Pad to even */
+	}
+
+	/* Image resolution - 28 bytes */
+	fz_write_data(ctx, out, ressig, 4);
+	fz_write_int16_be(ctx, out, 0x03ED);
+	fz_write_int16_be(ctx, out, 0); /* PString */
+	fz_write_int32_be(ctx, out, 16); /* Length */
+	/* Resolution is specified as a fixed 16.16 bits */
+	fz_write_int32_be(ctx, out, writer->super.xres);
+	fz_write_int16_be(ctx, out, 1); /* width:  1 --> resolution is pixels per inch */
+	fz_write_int16_be(ctx, out, 1); /* width:  1 --> resolution is pixels per inch */
+	fz_write_int32_be(ctx, out, writer->super.yres);
+	fz_write_int16_be(ctx, out, 1); /* height:  1 --> resolution is pixels per inch */
+	fz_write_int16_be(ctx, out, 1); /* height:  1 --> resolution is pixels per inch */
+
+	/* Layer and Mask Information Section */
+	fz_write_int32_be(ctx, out, 0);
+
+	/* Image Data Section */
+	fz_write_int16_be(ctx, out, 0); /* Raw image data */
+}
+
+static void
+psd_invert_buffer(unsigned char *buffer, int size)
+{
+	int k;
+
+	for (k = 0; k < size; k++)
+		buffer[k] = 255 - buffer[k];
+}
+
+static void
+psd_write_band(fz_context *ctx, fz_band_writer *writer_, int stride, int band_start, int band_height, const unsigned char *sp)
+{
+	psd_band_writer *writer = (psd_band_writer *)(void *)writer_;
+	fz_output *out = writer->super.out;
+	int y, x, k, finalband;
+	int w, h, n;
+	unsigned char buffer[256];
+	unsigned char *buffer_end = &buffer[sizeof(buffer)];
+	unsigned char *b;
+	int plane_inc;
+	int line_skip;
+	int num_additive = writer->num_additive;
+
+	if (!out)
+		return;
+
+	w = writer->super.w;
+	h = writer->super.h;
+	n = writer->super.n;
+
+	finalband = (band_start+band_height >= h);
+	if (finalband)
+		band_height = h - band_start;
+
+	plane_inc = w * (h - band_height);
+	line_skip = stride - w*n;
+	b = buffer;
+	if (writer->super.alpha)
+	{
+		const unsigned char *ap = &sp[n-1];
+		for (k = 0; k < n-1; k++)
+		{
+			for (y = 0; y < band_height; y++)
+			{
+				for (x = 0; x < w; x++)
+				{
+					int a = *ap;
+					ap += n;
+					*b++ = a != 0 ? (*sp * 255 + 128)/a : 0;
+					sp += n;
+					if (b == buffer_end)
+					{
+						if (k >= num_additive)
+							psd_invert_buffer(buffer, sizeof(buffer));
+						fz_write_data(ctx, out, buffer, sizeof(buffer));
+						b = buffer;
+					}
+				}
+				sp += line_skip;
+				ap += line_skip;
+			}
+			sp -= stride * (ptrdiff_t)band_height - 1;
+			ap -= stride * (ptrdiff_t)band_height;
+			if (b != buffer)
+			{
+				if (k >= num_additive)
+					psd_invert_buffer(buffer, sizeof(buffer));
+				fz_write_data(ctx, out, buffer, b - buffer);
+				b = buffer;
+			}
+			fz_seek_output(ctx, out, plane_inc, SEEK_CUR);
+		}
+		for (y = 0; y < band_height; y++)
+		{
+			for (x = 0; x < w; x++)
+			{
+				*b++ = *sp;
+				sp += n;
+				if (b == buffer_end)
+				{
+					fz_write_data(ctx, out, buffer, sizeof(buffer));
+					b = buffer;
+				}
+			}
+			sp += line_skip;
+		}
+		if (b != buffer)
+		{
+			fz_write_data(ctx, out, buffer, b - buffer);
+			b = buffer;
+		}
+		fz_seek_output(ctx, out, plane_inc, SEEK_CUR);
+	}
+	else
+	{
+		for (k = 0; k < n; k++)
+		{
+			for (y = 0; y < band_height; y++)
+			{
+				for (x = 0; x < w; x++)
+				{
+					*b++ = *sp;
+					sp += n;
+					if (b == buffer_end)
+					{
+						if (k >= num_additive)
+							psd_invert_buffer(buffer, sizeof(buffer));
+						fz_write_data(ctx, out, buffer, sizeof(buffer));
+						b = buffer;
+					}
+				}
+				sp += line_skip;
+			}
+			sp -= stride * (ptrdiff_t)band_height - 1;
+			if (b != buffer)
+			{
+				if (k >= num_additive)
+					psd_invert_buffer(buffer, sizeof(buffer));
+				fz_write_data(ctx, out, buffer, b - buffer);
+				b = buffer;
+			}
+			fz_seek_output(ctx, out, plane_inc, SEEK_CUR);
+		}
+	}
+	fz_seek_output(ctx, out, w * (band_height - h * (int64_t)n), SEEK_CUR);
+}
+
+static void
+psd_write_trailer(fz_context *ctx, fz_band_writer *writer_)
+{
+	psd_band_writer *writer = (psd_band_writer *)(void *)writer_;
+	fz_output *out = writer->super.out;
+
+	(void)out;
+	(void)writer;
+}
+
+static void
+psd_drop_band_writer(fz_context *ctx, fz_band_writer *writer_)
+{
+	psd_band_writer *writer = (psd_band_writer *)(void *)writer_;
+
+	(void)writer;
+}
+
+fz_band_writer *fz_new_psd_band_writer(fz_context *ctx, fz_output *out)
+{
+	psd_band_writer *writer = fz_new_band_writer(ctx, psd_band_writer, out);
+
+	writer->super.header = psd_write_header;
+	writer->super.band = psd_write_band;
+	writer->super.trailer = psd_write_trailer;
+	writer->super.drop = psd_drop_band_writer;
+
+	writer->num_additive = 0;
+
+	return &writer->super;
+}
+
+static fz_buffer *
+psd_from_pixmap(fz_context *ctx, fz_pixmap *pix, fz_color_params color_params, int drop)
+{
+	fz_buffer *buf = NULL;
+	fz_output *out = NULL;
+
+	fz_var(buf);
+	fz_var(out);
+
+	fz_try(ctx)
+	{
+		buf = fz_new_buffer(ctx, 1024);
+		out = fz_new_output_with_buffer(ctx, buf);
+		fz_write_pixmap_as_psd(ctx, out, pix);
+		fz_close_output(ctx, out);
+	}
+	fz_always(ctx)
+	{
+		if (drop)
+			fz_drop_pixmap(ctx, pix);
+		fz_drop_output(ctx, out);
+	}
+	fz_catch(ctx)
+	{
+		fz_drop_buffer(ctx, buf);
+		fz_rethrow(ctx);
+	}
+	return buf;
+}
+
+fz_buffer *
+fz_new_buffer_from_image_as_psd(fz_context *ctx, fz_image *image, fz_color_params color_params)
+{
+	fz_pixmap *pix = fz_get_pixmap_from_image(ctx, image, NULL, NULL, NULL, NULL);
+	return psd_from_pixmap(ctx, pix, color_params, 1);
+}
+
+fz_buffer *
+fz_new_buffer_from_pixmap_as_psd(fz_context *ctx, fz_pixmap *pix, fz_color_params color_params)
+{
+	return psd_from_pixmap(ctx, pix, color_params, 0);
+}