Fix lossless JPEG rotation when using libjpeg-8

This is mostly a port of the corresponding patch for gThumb by
Paolo Bacchilega (bug 612809). Since it's needed by the newer transupp
we also ship the internal jpegint.h header as done by digiKam to
workaround distros that do not ship it by default. Fixes bug 615387.

1 files changed, 157 insertions, 0 deletions

diff --git a/jpegutils/transupp-6b.h b/jpegutils/transupp-6b.h
new file mode 100644
index 00000000..9b89e4f0
--- /dev/null
+++ b/jpegutils/transupp-6b.h
@@ -0,0 +1,157 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+
+/*
+ *  GThumb
+ *
+ *  Copyright (C) 2001, 2002 The Free Software Foundation, Inc.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program 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 General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Street #330, Boston, MA 02111-1307, USA.
+ */
+
+/* based upon file transupp.h from the libjpeg package, original copyright 
+ * note follows:
+ *
+ * transupp.h
+ *
+ * Copyright (C) 1997, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains declarations for image transformation routines and
+ * other utility code used by the jpegtran sample application.  These are
+ * NOT part of the core JPEG library.  But we keep these routines separate
+ * from jpegtran.c to ease the task of maintaining jpegtran-like programs
+ * that have other user interfaces.
+ *
+ * NOTE: all the routines declared here have very specific requirements
+ * about when they are to be executed during the reading and writing of the
+ * source and destination files.  See the comments in transupp.c, or see
+ * jpegtran.c for an example of correct usage.
+ */
+
+/*
+ * Codes for supported types of image transformations.
+ */
+
+#ifdef HAVE_LIBJPEG
+
+
+#ifndef TRANSUPP_H
+#define TRANSUPP_H
+
+#include <jpeglib.h>
+
+
+typedef enum {
+	JXFORM_NONE,		/* no transformation */
+	JXFORM_FLIP_H,		/* horizontal flip */
+	JXFORM_FLIP_V,		/* vertical flip */
+	JXFORM_TRANSPOSE,	/* transpose across UL-to-LR axis */
+	JXFORM_TRANSVERSE,	/* transpose across UR-to-LL axis */
+	JXFORM_ROT_90,		/* 90-degree clockwise rotation */
+	JXFORM_ROT_180,		/* 180-degree rotation */
+	JXFORM_ROT_270		/* 270-degree clockwise (or 90 ccw) */
+} JXFORM_CODE;
+
+/*
+ * Although rotating and flipping data expressed as DCT coefficients is not
+ * hard, there is an asymmetry in the JPEG format specification for images
+ * whose dimensions aren't multiples of the iMCU size.  The right and bottom
+ * image edges are padded out to the next iMCU boundary with junk data; but
+ * no padding is possible at the top and left edges.  If we were to flip
+ * the whole image including the pad data, then pad garbage would become
+ * visible at the top and/or left, and real pixels would disappear into the
+ * pad margins --- perhaps permanently, since encoders & decoders may not
+ * bother to preserve DCT blocks that appear to be completely outside the
+ * nominal image area.  So, we have to exclude any partial iMCUs from the
+ * basic transformation.
+ *
+ * Transpose is the only transformation that can handle partial iMCUs at the
+ * right and bottom edges completely cleanly.  flip_h can flip partial iMCUs
+ * at the bottom, but leaves any partial iMCUs at the right edge untouched.
+ * Similarly flip_v leaves any partial iMCUs at the bottom edge untouched.
+ * The other transforms are defined as combinations of these basic transforms
+ * and process edge blocks in a way that preserves the equivalence.
+ *
+ * The "trim" option causes untransformable partial iMCUs to be dropped;
+ * this is not strictly lossless, but it usually gives the best-looking
+ * result for odd-size images.  Note that when this option is active,
+ * the expected mathematical equivalences between the transforms may not hold.
+ * (For example, -rot 270 -trim trims only the bottom edge, but -rot 90 -trim
+ * followed by -rot 180 -trim trims both edges.)
+ *
+ * We also offer a "force to grayscale" option, which simply discards the
+ * chrominance channels of a YCbCr image.  This is lossless in the sense that
+ * the luminance channel is preserved exactly.  It's not the same kind of
+ * thing as the rotate/flip transformations, but it's convenient to handle it
+ * as part of this package, mainly because the transformation routines have to
+ * be aware of the option to know how many components to work on.
+ */
+
+typedef struct {
+  /* Options: set by caller */
+  JXFORM_CODE transform;	/* image transform operator */
+  boolean trim;			/* if TRUE, trim partial MCUs as needed */
+  boolean force_grayscale;	/* if TRUE, convert color image to grayscale */
+
+  /* Internal workspace: caller should not touch these */
+  int num_components;		/* # of components in workspace */
+  jvirt_barray_ptr * workspace_coef_arrays; /* workspace for transformations */
+} jpeg_transform_info;
+
+
+/* Request any required workspace */
+void jtransform_request_workspace   (j_decompress_ptr     srcinfo, 
+				     jpeg_transform_info *info);
+
+/* Adjust output image parameters */
+
+jvirt_barray_ptr * jtransform_adjust_parameters (j_decompress_ptr     srcinfo, 
+						 j_compress_ptr       dstinfo,
+						 jvirt_barray_ptr    *src_coef_arrays,
+						 jpeg_transform_info *info);
+
+/* Execute the actual transformation, if any */
+void jtransform_execute_transformation (j_decompress_ptr     srcinfo, 
+					j_compress_ptr       dstinfo,
+					jvirt_barray_ptr    *src_coef_arrays,
+					jpeg_transform_info *info);
+
+
+/*
+ * Support for copying optional markers from source to destination file.
+ */
+
+typedef enum {
+	JCOPYOPT_NONE,		/* copy no optional markers */
+	JCOPYOPT_COMMENTS,	/* copy only comment (COM) markers */
+	JCOPYOPT_ALL		/* copy all optional markers */
+} JCOPY_OPTION;
+
+#define JCOPYOPT_DEFAULT  JCOPYOPT_COMMENTS	/* recommended default */
+
+/* Setup decompression object to save desired markers in memory */
+void jcopy_markers_setup (j_decompress_ptr srcinfo, 
+			  JCOPY_OPTION     option);
+
+/* Copy markers saved in the given source object to the destination object */
+void jcopy_markers_execute (j_decompress_ptr srcinfo, 
+			    j_compress_ptr   dstinfo,
+			    JCOPY_OPTION     option);
+
+
+#endif /* TRANSUPP_H */
+
+#endif /* HAVE_LIBJPEG */