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-rw-r--r--graphics/jpeg/patches/patch-ab1501
1 files changed, 1501 insertions, 0 deletions
diff --git a/graphics/jpeg/patches/patch-ab b/graphics/jpeg/patches/patch-ab
new file mode 100644
index 00000000000..f0e570dc5b6
--- /dev/null
+++ b/graphics/jpeg/patches/patch-ab
@@ -0,0 +1,1501 @@
+$NetBSD: patch-ab,v 1.1 2007/06/05 22:07:26 tnn Exp $
+
+--- transupp.c.orig 2007-06-05 22:33:58.000000000 +0200
++++ transupp.c
+@@ -1,7 +1,7 @@
+ /*
+ * transupp.c
+ *
+- * Copyright (C) 1997, Thomas G. Lane.
++ * Copyright (C) 1997-2001, 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.
+ *
+@@ -20,6 +20,7 @@
+ #include "jinclude.h"
+ #include "jpeglib.h"
+ #include "transupp.h" /* My own external interface */
++#include <ctype.h> /* to declare isdigit() */
+
+
+ #if TRANSFORMS_SUPPORTED
+@@ -28,7 +29,8 @@
+ * Lossless image transformation routines. These routines work on DCT
+ * coefficient arrays and thus do not require any lossy decompression
+ * or recompression of the image.
+- * Thanks to Guido Vollbeding for the initial design and code of this feature.
++ * Thanks to Guido Vollbeding for the initial design and code of this feature,
++ * and to Ben Jackson for introducing the cropping feature.
+ *
+ * Horizontal flipping is done in-place, using a single top-to-bottom
+ * pass through the virtual source array. It will thus be much the
+@@ -42,6 +44,13 @@
+ * arrays for most of the transforms. That could result in much thrashing
+ * if the image is larger than main memory.
+ *
++ * If cropping or trimming is involved, the destination arrays may be smaller
++ * than the source arrays. Note it is not possible to do horizontal flip
++ * in-place when a nonzero Y crop offset is specified, since we'd have to move
++ * data from one block row to another but the virtual array manager doesn't
++ * guarantee we can touch more than one row at a time. So in that case,
++ * we have to use a separate destination array.
++ *
+ * Some notes about the operating environment of the individual transform
+ * routines:
+ * 1. Both the source and destination virtual arrays are allocated from the
+@@ -54,20 +63,65 @@
+ * and we may as well take that as the effective iMCU size.
+ * 4. When "trim" is in effect, the destination's dimensions will be the
+ * trimmed values but the source's will be untrimmed.
+- * 5. All the routines assume that the source and destination buffers are
++ * 5. When "crop" is in effect, the destination's dimensions will be the
++ * cropped values but the source's will be uncropped. Each transform
++ * routine is responsible for picking up source data starting at the
++ * correct X and Y offset for the crop region. (The X and Y offsets
++ * passed to the transform routines are measured in iMCU blocks of the
++ * destination.)
++ * 6. All the routines assume that the source and destination buffers are
+ * padded out to a full iMCU boundary. This is true, although for the
+ * source buffer it is an undocumented property of jdcoefct.c.
+- * Notes 2,3,4 boil down to this: generally we should use the destination's
+- * dimensions and ignore the source's.
+ */
+
+
+ LOCAL(void)
+-do_flip_h (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
+- jvirt_barray_ptr *src_coef_arrays)
+-/* Horizontal flip; done in-place, so no separate dest array is required */
++do_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
++ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
++ jvirt_barray_ptr *src_coef_arrays,
++ jvirt_barray_ptr *dst_coef_arrays)
++/* Crop. This is only used when no rotate/flip is requested with the crop. */
++{
++ JDIMENSION dst_blk_y, x_crop_blocks, y_crop_blocks;
++ int ci, offset_y;
++ JBLOCKARRAY src_buffer, dst_buffer;
++ jpeg_component_info *compptr;
++
++ /* We simply have to copy the right amount of data (the destination's
++ * image size) starting at the given X and Y offsets in the source.
++ */
++ for (ci = 0; ci < dstinfo->num_components; ci++) {
++ compptr = dstinfo->comp_info + ci;
++ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
++ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
++ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
++ dst_blk_y += compptr->v_samp_factor) {
++ dst_buffer = (*srcinfo->mem->access_virt_barray)
++ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
++ (JDIMENSION) compptr->v_samp_factor, TRUE);
++ src_buffer = (*srcinfo->mem->access_virt_barray)
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ dst_blk_y + y_crop_blocks,
++ (JDIMENSION) compptr->v_samp_factor, FALSE);
++ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
++ jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
++ dst_buffer[offset_y],
++ compptr->width_in_blocks);
++ }
++ }
++ }
++}
++
++
++LOCAL(void)
++do_flip_h_no_crop (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
++ JDIMENSION x_crop_offset,
++ jvirt_barray_ptr *src_coef_arrays)
++/* Horizontal flip; done in-place, so no separate dest array is required.
++ * NB: this only works when y_crop_offset is zero.
++ */
+ {
+- JDIMENSION MCU_cols, comp_width, blk_x, blk_y;
++ JDIMENSION MCU_cols, comp_width, blk_x, blk_y, x_crop_blocks;
+ int ci, k, offset_y;
+ JBLOCKARRAY buffer;
+ JCOEFPTR ptr1, ptr2;
+@@ -79,17 +133,19 @@ do_flip_h (j_decompress_ptr srcinfo, j_c
+ * mirroring by changing the signs of odd-numbered columns.
+ * Partial iMCUs at the right edge are left untouched.
+ */
+- MCU_cols = dstinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
++ MCU_cols = srcinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_width = MCU_cols * compptr->h_samp_factor;
++ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
+ for (blk_y = 0; blk_y < compptr->height_in_blocks;
+ blk_y += compptr->v_samp_factor) {
+ buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci], blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
++ /* Do the mirroring */
+ for (blk_x = 0; blk_x * 2 < comp_width; blk_x++) {
+ ptr1 = buffer[offset_y][blk_x];
+ ptr2 = buffer[offset_y][comp_width - blk_x - 1];
+@@ -105,6 +161,79 @@ do_flip_h (j_decompress_ptr srcinfo, j_c
+ *ptr2++ = -temp1;
+ }
+ }
++ if (x_crop_blocks > 0) {
++ /* Now left-justify the portion of the data to be kept.
++ * We can't use a single jcopy_block_row() call because that routine
++ * depends on memcpy(), whose behavior is unspecified for overlapping
++ * source and destination areas. Sigh.
++ */
++ for (blk_x = 0; blk_x < compptr->width_in_blocks; blk_x++) {
++ jcopy_block_row(buffer[offset_y] + blk_x + x_crop_blocks,
++ buffer[offset_y] + blk_x,
++ (JDIMENSION) 1);
++ }
++ }
++ }
++ }
++ }
++}
++
++
++LOCAL(void)
++do_flip_h (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
++ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
++ jvirt_barray_ptr *src_coef_arrays,
++ jvirt_barray_ptr *dst_coef_arrays)
++/* Horizontal flip in general cropping case */
++{
++ JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;
++ JDIMENSION x_crop_blocks, y_crop_blocks;
++ int ci, k, offset_y;
++ JBLOCKARRAY src_buffer, dst_buffer;
++ JBLOCKROW src_row_ptr, dst_row_ptr;
++ JCOEFPTR src_ptr, dst_ptr;
++ jpeg_component_info *compptr;
++
++ /* Here we must output into a separate array because we can't touch
++ * different rows of a single virtual array simultaneously. Otherwise,
++ * this is essentially the same as the routine above.
++ */
++ MCU_cols = srcinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
++
++ for (ci = 0; ci < dstinfo->num_components; ci++) {
++ compptr = dstinfo->comp_info + ci;
++ comp_width = MCU_cols * compptr->h_samp_factor;
++ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
++ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
++ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
++ dst_blk_y += compptr->v_samp_factor) {
++ dst_buffer = (*srcinfo->mem->access_virt_barray)
++ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
++ (JDIMENSION) compptr->v_samp_factor, TRUE);
++ src_buffer = (*srcinfo->mem->access_virt_barray)
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ dst_blk_y + y_crop_blocks,
++ (JDIMENSION) compptr->v_samp_factor, FALSE);
++ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
++ dst_row_ptr = dst_buffer[offset_y];
++ src_row_ptr = src_buffer[offset_y];
++ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
++ if (x_crop_blocks + dst_blk_x < comp_width) {
++ /* Do the mirrorable blocks */
++ dst_ptr = dst_row_ptr[dst_blk_x];
++ src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
++ /* this unrolled loop doesn't need to know which row it's on... */
++ for (k = 0; k < DCTSIZE2; k += 2) {
++ *dst_ptr++ = *src_ptr++; /* copy even column */
++ *dst_ptr++ = - *src_ptr++; /* copy odd column with sign change */
++ }
++ } else {
++ /* Copy last partial block(s) verbatim */
++ jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,
++ dst_row_ptr + dst_blk_x,
++ (JDIMENSION) 1);
++ }
++ }
+ }
+ }
+ }
+@@ -113,11 +242,13 @@ do_flip_h (j_decompress_ptr srcinfo, j_c
+
+ LOCAL(void)
+ do_flip_v (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
++ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+ /* Vertical flip */
+ {
+ JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;
++ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JBLOCKROW src_row_ptr, dst_row_ptr;
+@@ -131,33 +262,38 @@ do_flip_v (j_decompress_ptr srcinfo, j_c
+ * of odd-numbered rows.
+ * Partial iMCUs at the bottom edge are copied verbatim.
+ */
+- MCU_rows = dstinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE);
++ MCU_rows = srcinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_height = MCU_rows * compptr->v_samp_factor;
++ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
++ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+- if (dst_blk_y < comp_height) {
++ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Row is within the mirrorable area. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+- comp_height - dst_blk_y - (JDIMENSION) compptr->v_samp_factor,
++ comp_height - y_crop_blocks - dst_blk_y -
++ (JDIMENSION) compptr->v_samp_factor,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ } else {
+ /* Bottom-edge blocks will be copied verbatim. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+- ((j_common_ptr) srcinfo, src_coef_arrays[ci], dst_blk_y,
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ dst_blk_y + y_crop_blocks,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ }
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+- if (dst_blk_y < comp_height) {
++ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Row is within the mirrorable area. */
+ dst_row_ptr = dst_buffer[offset_y];
+ src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];
++ src_row_ptr += x_crop_blocks;
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x++) {
+ dst_ptr = dst_row_ptr[dst_blk_x];
+@@ -173,7 +309,8 @@ do_flip_v (j_decompress_ptr srcinfo, j_c
+ }
+ } else {
+ /* Just copy row verbatim. */
+- jcopy_block_row(src_buffer[offset_y], dst_buffer[offset_y],
++ jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
++ dst_buffer[offset_y],
+ compptr->width_in_blocks);
+ }
+ }
+@@ -184,11 +321,12 @@ do_flip_v (j_decompress_ptr srcinfo, j_c
+
+ LOCAL(void)
+ do_transpose (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
++ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+ /* Transpose source into destination */
+ {
+- JDIMENSION dst_blk_x, dst_blk_y;
++ JDIMENSION dst_blk_x, dst_blk_y, x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_x, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JCOEFPTR src_ptr, dst_ptr;
+@@ -201,6 +339,8 @@ do_transpose (j_decompress_ptr srcinfo,
+ */
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
++ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
++ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+@@ -210,11 +350,12 @@ do_transpose (j_decompress_ptr srcinfo,
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x += compptr->h_samp_factor) {
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+- ((j_common_ptr) srcinfo, src_coef_arrays[ci], dst_blk_x,
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ dst_blk_x + x_crop_blocks,
+ (JDIMENSION) compptr->h_samp_factor, FALSE);
+ for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
+- src_ptr = src_buffer[offset_x][dst_blk_y + offset_y];
+ dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
++ src_ptr = src_buffer[offset_x][dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++)
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+@@ -228,6 +369,7 @@ do_transpose (j_decompress_ptr srcinfo,
+
+ LOCAL(void)
+ do_rot_90 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
++ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+ /* 90 degree rotation is equivalent to
+@@ -237,6 +379,7 @@ do_rot_90 (j_decompress_ptr srcinfo, j_c
+ */
+ {
+ JDIMENSION MCU_cols, comp_width, dst_blk_x, dst_blk_y;
++ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_x, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JCOEFPTR src_ptr, dst_ptr;
+@@ -246,11 +389,13 @@ do_rot_90 (j_decompress_ptr srcinfo, j_c
+ * at the (output) right edge properly. They just get transposed and
+ * not mirrored.
+ */
+- MCU_cols = dstinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
++ MCU_cols = srcinfo->image_height / (dstinfo->max_h_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_width = MCU_cols * compptr->h_samp_factor;
++ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
++ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+@@ -259,15 +404,26 @@ do_rot_90 (j_decompress_ptr srcinfo, j_c
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x += compptr->h_samp_factor) {
+- src_buffer = (*srcinfo->mem->access_virt_barray)
+- ((j_common_ptr) srcinfo, src_coef_arrays[ci], dst_blk_x,
+- (JDIMENSION) compptr->h_samp_factor, FALSE);
++ if (x_crop_blocks + dst_blk_x < comp_width) {
++ /* Block is within the mirrorable area. */
++ src_buffer = (*srcinfo->mem->access_virt_barray)
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ comp_width - x_crop_blocks - dst_blk_x -
++ (JDIMENSION) compptr->h_samp_factor,
++ (JDIMENSION) compptr->h_samp_factor, FALSE);
++ } else {
++ /* Edge blocks are transposed but not mirrored. */
++ src_buffer = (*srcinfo->mem->access_virt_barray)
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ dst_blk_x + x_crop_blocks,
++ (JDIMENSION) compptr->h_samp_factor, FALSE);
++ }
+ for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
+- src_ptr = src_buffer[offset_x][dst_blk_y + offset_y];
+- if (dst_blk_x < comp_width) {
++ dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
++ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Block is within the mirrorable area. */
+- dst_ptr = dst_buffer[offset_y]
+- [comp_width - dst_blk_x - offset_x - 1];
++ src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
++ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+@@ -277,7 +433,8 @@ do_rot_90 (j_decompress_ptr srcinfo, j_c
+ }
+ } else {
+ /* Edge blocks are transposed but not mirrored. */
+- dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
++ src_ptr = src_buffer[offset_x]
++ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++)
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+@@ -292,6 +449,7 @@ do_rot_90 (j_decompress_ptr srcinfo, j_c
+
+ LOCAL(void)
+ do_rot_270 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
++ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+ /* 270 degree rotation is equivalent to
+@@ -301,6 +459,7 @@ do_rot_270 (j_decompress_ptr srcinfo, j_
+ */
+ {
+ JDIMENSION MCU_rows, comp_height, dst_blk_x, dst_blk_y;
++ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_x, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JCOEFPTR src_ptr, dst_ptr;
+@@ -310,11 +469,13 @@ do_rot_270 (j_decompress_ptr srcinfo, j_
+ * at the (output) bottom edge properly. They just get transposed and
+ * not mirrored.
+ */
+- MCU_rows = dstinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE);
++ MCU_rows = srcinfo->image_width / (dstinfo->max_v_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_height = MCU_rows * compptr->v_samp_factor;
++ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
++ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+@@ -324,14 +485,15 @@ do_rot_270 (j_decompress_ptr srcinfo, j_
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x += compptr->h_samp_factor) {
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+- ((j_common_ptr) srcinfo, src_coef_arrays[ci], dst_blk_x,
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ dst_blk_x + x_crop_blocks,
+ (JDIMENSION) compptr->h_samp_factor, FALSE);
+ for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
+ dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
+- if (dst_blk_y < comp_height) {
++ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Block is within the mirrorable area. */
+ src_ptr = src_buffer[offset_x]
+- [comp_height - dst_blk_y - offset_y - 1];
++ [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++) {
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+@@ -341,7 +503,8 @@ do_rot_270 (j_decompress_ptr srcinfo, j_
+ }
+ } else {
+ /* Edge blocks are transposed but not mirrored. */
+- src_ptr = src_buffer[offset_x][dst_blk_y + offset_y];
++ src_ptr = src_buffer[offset_x]
++ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++)
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+@@ -356,6 +519,7 @@ do_rot_270 (j_decompress_ptr srcinfo, j_
+
+ LOCAL(void)
+ do_rot_180 (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
++ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+ /* 180 degree rotation is equivalent to
+@@ -365,89 +529,93 @@ do_rot_180 (j_decompress_ptr srcinfo, j_
+ */
+ {
+ JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;
++ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JBLOCKROW src_row_ptr, dst_row_ptr;
+ JCOEFPTR src_ptr, dst_ptr;
+ jpeg_component_info *compptr;
+
+- MCU_cols = dstinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
+- MCU_rows = dstinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE);
++ MCU_cols = srcinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
++ MCU_rows = srcinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_width = MCU_cols * compptr->h_samp_factor;
+ comp_height = MCU_rows * compptr->v_samp_factor;
++ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
++ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, dst_coef_arrays[ci], dst_blk_y,
+ (JDIMENSION) compptr->v_samp_factor, TRUE);
+- if (dst_blk_y < comp_height) {
++ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Row is within the vertically mirrorable area. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
+- comp_height - dst_blk_y - (JDIMENSION) compptr->v_samp_factor,
++ comp_height - y_crop_blocks - dst_blk_y -
++ (JDIMENSION) compptr->v_samp_factor,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ } else {
+ /* Bottom-edge rows are only mirrored horizontally. */
+ src_buffer = (*srcinfo->mem->access_virt_barray)
+- ((j_common_ptr) srcinfo, src_coef_arrays[ci], dst_blk_y,
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ dst_blk_y + y_crop_blocks,
+ (JDIMENSION) compptr->v_samp_factor, FALSE);
+ }
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+- if (dst_blk_y < comp_height) {
++ dst_row_ptr = dst_buffer[offset_y];
++ if (y_crop_blocks + dst_blk_y < comp_height) {
+ /* Row is within the mirrorable area. */
+- dst_row_ptr = dst_buffer[offset_y];
+ src_row_ptr = src_buffer[compptr->v_samp_factor - offset_y - 1];
+- /* Process the blocks that can be mirrored both ways. */
+- for (dst_blk_x = 0; dst_blk_x < comp_width; dst_blk_x++) {
++ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
+ dst_ptr = dst_row_ptr[dst_blk_x];
+- src_ptr = src_row_ptr[comp_width - dst_blk_x - 1];
+- for (i = 0; i < DCTSIZE; i += 2) {
+- /* For even row, negate every odd column. */
+- for (j = 0; j < DCTSIZE; j += 2) {
+- *dst_ptr++ = *src_ptr++;
+- *dst_ptr++ = - *src_ptr++;
++ if (x_crop_blocks + dst_blk_x < comp_width) {
++ /* Process the blocks that can be mirrored both ways. */
++ src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
++ for (i = 0; i < DCTSIZE; i += 2) {
++ /* For even row, negate every odd column. */
++ for (j = 0; j < DCTSIZE; j += 2) {
++ *dst_ptr++ = *src_ptr++;
++ *dst_ptr++ = - *src_ptr++;
++ }
++ /* For odd row, negate every even column. */
++ for (j = 0; j < DCTSIZE; j += 2) {
++ *dst_ptr++ = - *src_ptr++;
++ *dst_ptr++ = *src_ptr++;
++ }
+ }
+- /* For odd row, negate every even column. */
+- for (j = 0; j < DCTSIZE; j += 2) {
+- *dst_ptr++ = - *src_ptr++;
+- *dst_ptr++ = *src_ptr++;
++ } else {
++ /* Any remaining right-edge blocks are only mirrored vertically. */
++ src_ptr = src_row_ptr[x_crop_blocks + dst_blk_x];
++ for (i = 0; i < DCTSIZE; i += 2) {
++ for (j = 0; j < DCTSIZE; j++)
++ *dst_ptr++ = *src_ptr++;
++ for (j = 0; j < DCTSIZE; j++)
++ *dst_ptr++ = - *src_ptr++;
+ }
+ }
+ }
+- /* Any remaining right-edge blocks are only mirrored vertically. */
+- for (; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
+- dst_ptr = dst_row_ptr[dst_blk_x];
+- src_ptr = src_row_ptr[dst_blk_x];
+- for (i = 0; i < DCTSIZE; i += 2) {
+- for (j = 0; j < DCTSIZE; j++)
+- *dst_ptr++ = *src_ptr++;
+- for (j = 0; j < DCTSIZE; j++)
+- *dst_ptr++ = - *src_ptr++;
+- }
+- }
+ } else {
+ /* Remaining rows are just mirrored horizontally. */
+- dst_row_ptr = dst_buffer[offset_y];
+ src_row_ptr = src_buffer[offset_y];
+- /* Process the blocks that can be mirrored. */
+- for (dst_blk_x = 0; dst_blk_x < comp_width; dst_blk_x++) {
+- dst_ptr = dst_row_ptr[dst_blk_x];
+- src_ptr = src_row_ptr[comp_width - dst_blk_x - 1];
+- for (i = 0; i < DCTSIZE2; i += 2) {
+- *dst_ptr++ = *src_ptr++;
+- *dst_ptr++ = - *src_ptr++;
++ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
++ if (x_crop_blocks + dst_blk_x < comp_width) {
++ /* Process the blocks that can be mirrored. */
++ dst_ptr = dst_row_ptr[dst_blk_x];
++ src_ptr = src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
++ for (i = 0; i < DCTSIZE2; i += 2) {
++ *dst_ptr++ = *src_ptr++;
++ *dst_ptr++ = - *src_ptr++;
++ }
++ } else {
++ /* Any remaining right-edge blocks are only copied. */
++ jcopy_block_row(src_row_ptr + dst_blk_x + x_crop_blocks,
++ dst_row_ptr + dst_blk_x,
++ (JDIMENSION) 1);
+ }
+ }
+- /* Any remaining right-edge blocks are only copied. */
+- for (; dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
+- dst_ptr = dst_row_ptr[dst_blk_x];
+- src_ptr = src_row_ptr[dst_blk_x];
+- for (i = 0; i < DCTSIZE2; i++)
+- *dst_ptr++ = *src_ptr++;
+- }
+ }
+ }
+ }
+@@ -457,6 +625,7 @@ do_rot_180 (j_decompress_ptr srcinfo, j_
+
+ LOCAL(void)
+ do_transverse (j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
++ JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
+ jvirt_barray_ptr *src_coef_arrays,
+ jvirt_barray_ptr *dst_coef_arrays)
+ /* Transverse transpose is equivalent to
+@@ -470,18 +639,21 @@ do_transverse (j_decompress_ptr srcinfo,
+ */
+ {
+ JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, dst_blk_x, dst_blk_y;
++ JDIMENSION x_crop_blocks, y_crop_blocks;
+ int ci, i, j, offset_x, offset_y;
+ JBLOCKARRAY src_buffer, dst_buffer;
+ JCOEFPTR src_ptr, dst_ptr;
+ jpeg_component_info *compptr;
+
+- MCU_cols = dstinfo->image_width / (dstinfo->max_h_samp_factor * DCTSIZE);
+- MCU_rows = dstinfo->image_height / (dstinfo->max_v_samp_factor * DCTSIZE);
++ MCU_cols = srcinfo->image_height / (dstinfo->max_h_samp_factor * DCTSIZE);
++ MCU_rows = srcinfo->image_width / (dstinfo->max_v_samp_factor * DCTSIZE);
+
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+ comp_width = MCU_cols * compptr->h_samp_factor;
+ comp_height = MCU_rows * compptr->v_samp_factor;
++ x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
++ y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
+ for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
+ dst_blk_y += compptr->v_samp_factor) {
+ dst_buffer = (*srcinfo->mem->access_virt_barray)
+@@ -490,17 +662,26 @@ do_transverse (j_decompress_ptr srcinfo,
+ for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
+ for (dst_blk_x = 0; dst_blk_x < compptr->width_in_blocks;
+ dst_blk_x += compptr->h_samp_factor) {
+- src_buffer = (*srcinfo->mem->access_virt_barray)
+- ((j_common_ptr) srcinfo, src_coef_arrays[ci], dst_blk_x,
+- (JDIMENSION) compptr->h_samp_factor, FALSE);
++ if (x_crop_blocks + dst_blk_x < comp_width) {
++ /* Block is within the mirrorable area. */
++ src_buffer = (*srcinfo->mem->access_virt_barray)
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ comp_width - x_crop_blocks - dst_blk_x -
++ (JDIMENSION) compptr->h_samp_factor,
++ (JDIMENSION) compptr->h_samp_factor, FALSE);
++ } else {
++ src_buffer = (*srcinfo->mem->access_virt_barray)
++ ((j_common_ptr) srcinfo, src_coef_arrays[ci],
++ dst_blk_x + x_crop_blocks,
++ (JDIMENSION) compptr->h_samp_factor, FALSE);
++ }
+ for (offset_x = 0; offset_x < compptr->h_samp_factor; offset_x++) {
+- if (dst_blk_y < comp_height) {
+- src_ptr = src_buffer[offset_x]
+- [comp_height - dst_blk_y - offset_y - 1];
+- if (dst_blk_x < comp_width) {
++ dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
++ if (y_crop_blocks + dst_blk_y < comp_height) {
++ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Block is within the mirrorable area. */
+- dst_ptr = dst_buffer[offset_y]
+- [comp_width - dst_blk_x - offset_x - 1];
++ src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
++ [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++) {
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+@@ -516,7 +697,8 @@ do_transverse (j_decompress_ptr srcinfo,
+ }
+ } else {
+ /* Right-edge blocks are mirrored in y only */
+- dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
++ src_ptr = src_buffer[offset_x]
++ [comp_height - y_crop_blocks - dst_blk_y - offset_y - 1];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++) {
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+@@ -526,11 +708,10 @@ do_transverse (j_decompress_ptr srcinfo,
+ }
+ }
+ } else {
+- src_ptr = src_buffer[offset_x][dst_blk_y + offset_y];
+- if (dst_blk_x < comp_width) {
++ if (x_crop_blocks + dst_blk_x < comp_width) {
+ /* Bottom-edge blocks are mirrored in x only */
+- dst_ptr = dst_buffer[offset_y]
+- [comp_width - dst_blk_x - offset_x - 1];
++ src_ptr = src_buffer[compptr->h_samp_factor - offset_x - 1]
++ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++) {
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+@@ -540,7 +721,8 @@ do_transverse (j_decompress_ptr srcinfo,
+ }
+ } else {
+ /* At lower right corner, just transpose, no mirroring */
+- dst_ptr = dst_buffer[offset_y][dst_blk_x + offset_x];
++ src_ptr = src_buffer[offset_x]
++ [dst_blk_y + offset_y + y_crop_blocks];
+ for (i = 0; i < DCTSIZE; i++)
+ for (j = 0; j < DCTSIZE; j++)
+ dst_ptr[j*DCTSIZE+i] = src_ptr[i*DCTSIZE+j];
+@@ -554,8 +736,116 @@ do_transverse (j_decompress_ptr srcinfo,
+ }
+
+
++/* Parse an unsigned integer: subroutine for jtransform_parse_crop_spec.
++ * Returns TRUE if valid integer found, FALSE if not.
++ * *strptr is advanced over the digit string, and *result is set to its value.
++ */
++
++LOCAL(boolean)
++jt_read_integer (const char ** strptr, JDIMENSION * result)
++{
++ const char * ptr = *strptr;
++ JDIMENSION val = 0;
++
++ for (; isdigit(*ptr); ptr++) {
++ val = val * 10 + (JDIMENSION) (*ptr - '0');
++ }
++ *result = val;
++ if (ptr == *strptr)
++ return FALSE; /* oops, no digits */
++ *strptr = ptr;
++ return TRUE;
++}
++
++
++/* Parse a crop specification (written in X11 geometry style).
++ * The routine returns TRUE if the spec string is valid, FALSE if not.
++ *
++ * The crop spec string should have the format
++ * <width>x<height>{+-}<xoffset>{+-}<yoffset>
++ * where width, height, xoffset, and yoffset are unsigned integers.
++ * Each of the elements can be omitted to indicate a default value.
++ * (A weakness of this style is that it is not possible to omit xoffset
++ * while specifying yoffset, since they look alike.)
++ *
++ * This code is loosely based on XParseGeometry from the X11 distribution.
++ */
++
++GLOBAL(boolean)
++jtransform_parse_crop_spec (jpeg_transform_info *info, const char *spec)
++{
++ info->crop = FALSE;
++ info->crop_width_set = JCROP_UNSET;
++ info->crop_height_set = JCROP_UNSET;
++ info->crop_xoffset_set = JCROP_UNSET;
++ info->crop_yoffset_set = JCROP_UNSET;
++
++ if (isdigit(*spec)) {
++ /* fetch width */
++ if (! jt_read_integer(&spec, &info->crop_width))
++ return FALSE;
++ info->crop_width_set = JCROP_POS;
++ }
++ if (*spec == 'x' || *spec == 'X') {
++ /* fetch height */
++ spec++;
++ if (! jt_read_integer(&spec, &info->crop_height))
++ return FALSE;
++ info->crop_height_set = JCROP_POS;
++ }
++ if (*spec == '+' || *spec == '-') {
++ /* fetch xoffset */
++ info->crop_xoffset_set = (*spec == '-') ? JCROP_NEG : JCROP_POS;
++ spec++;
++ if (! jt_read_integer(&spec, &info->crop_xoffset))
++ return FALSE;
++ }
++ if (*spec == '+' || *spec == '-') {
++ /* fetch yoffset */
++ info->crop_yoffset_set = (*spec == '-') ? JCROP_NEG : JCROP_POS;
++ spec++;
++ if (! jt_read_integer(&spec, &info->crop_yoffset))
++ return FALSE;
++ }
++ /* We had better have gotten to the end of the string. */
++ if (*spec != '\0')
++ return FALSE;
++ info->crop = TRUE;
++ return TRUE;
++}
++
++
++/* Trim off any partial iMCUs on the indicated destination edge */
++
++LOCAL(void)
++trim_right_edge (jpeg_transform_info *info, JDIMENSION full_width)
++{
++ JDIMENSION MCU_cols;
++
++ MCU_cols = info->output_width / (info->max_h_samp_factor * DCTSIZE);
++ if (MCU_cols > 0 && info->x_crop_offset + MCU_cols ==
++ full_width / (info->max_h_samp_factor * DCTSIZE))
++ info->output_width = MCU_cols * (info->max_h_samp_factor * DCTSIZE);
++}
++
++LOCAL(void)
++trim_bottom_edge (jpeg_transform_info *info, JDIMENSION full_height)
++{
++ JDIMENSION MCU_rows;
++
++ MCU_rows = info->output_height / (info->max_v_samp_factor * DCTSIZE);
++ if (MCU_rows > 0 && info->y_crop_offset + MCU_rows ==
++ full_height / (info->max_v_samp_factor * DCTSIZE))
++ info->output_height = MCU_rows * (info->max_v_samp_factor * DCTSIZE);
++}
++
++
+ /* Request any required workspace.
+ *
++ * This routine figures out the size that the output image will be
++ * (which implies that all the transform parameters must be set before
++ * it is called).
++ *
+ * We allocate the workspace virtual arrays from the source decompression
+ * object, so that all the arrays (both the original data and the workspace)
+ * will be taken into account while making memory management decisions.
+@@ -569,9 +859,13 @@ jtransform_request_workspace (j_decompre
+ jpeg_transform_info *info)
+ {
+ jvirt_barray_ptr *coef_arrays = NULL;
++ boolean need_workspace, transpose_it;
+ jpeg_component_info *compptr;
+- int ci;
++ JDIMENSION xoffset, yoffset, width_in_iMCUs, height_in_iMCUs;
++ JDIMENSION width_in_blocks, height_in_blocks;
++ int ci, h_samp_factor, v_samp_factor;
+
++ /* Determine number of components in output image */
+ if (info->force_grayscale &&
+ srcinfo->jpeg_color_space == JCS_YCbCr &&
+ srcinfo->num_components == 3) {
+@@ -581,55 +875,181 @@ jtransform_request_workspace (j_decompre
+ /* Process all the components */
+ info->num_components = srcinfo->num_components;
+ }
++ /* If there is only one output component, force the iMCU size to be 1;
++ * else use the source iMCU size. (This allows us to do the right thing
++ * when reducing color to grayscale, and also provides a handy way of
++ * cleaning up "funny" grayscale images whose sampling factors are not 1x1.)
++ */
++
++ switch (info->transform) {
++ case JXFORM_TRANSPOSE:
++ case JXFORM_TRANSVERSE:
++ case JXFORM_ROT_90:
++ case JXFORM_ROT_270:
++ info->output_width = srcinfo->image_height;
++ info->output_height = srcinfo->image_width;
++ if (info->num_components == 1) {
++ info->max_h_samp_factor = 1;
++ info->max_v_samp_factor = 1;
++ } else {
++ info->max_h_samp_factor = srcinfo->max_v_samp_factor;
++ info->max_v_samp_factor = srcinfo->max_h_samp_factor;
++ }
++ break;
++ default:
++ info->output_width = srcinfo->image_width;
++ info->output_height = srcinfo->image_height;
++ if (info->num_components == 1) {
++ info->max_h_samp_factor = 1;
++ info->max_v_samp_factor = 1;
++ } else {
++ info->max_h_samp_factor = srcinfo->max_h_samp_factor;
++ info->max_v_samp_factor = srcinfo->max_v_samp_factor;
++ }
++ break;
++ }
++
++ /* If cropping has been requested, compute the crop area's position and
++ * dimensions, ensuring that its upper left corner falls at an iMCU boundary.
++ */
++ if (info->crop) {
++ /* Insert default values for unset crop parameters */
++ if (info->crop_xoffset_set == JCROP_UNSET)
++ info->crop_xoffset = 0; /* default to +0 */
++ if (info->crop_yoffset_set == JCROP_UNSET)
++ info->crop_yoffset = 0; /* default to +0 */
++ if (info->crop_xoffset >= info->output_width ||
++ info->crop_yoffset >= info->output_height)
++ ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
++ if (info->crop_width_set == JCROP_UNSET)
++ info->crop_width = info->output_width - info->crop_xoffset;
++ if (info->crop_height_set == JCROP_UNSET)
++ info->crop_height = info->output_height - info->crop_yoffset;
++ /* Ensure parameters are valid */
++ if (info->crop_width <= 0 || info->crop_width > info->output_width ||
++ info->crop_height <= 0 || info->crop_height > info->output_height ||
++ info->crop_xoffset > info->output_width - info->crop_width ||
++ info->crop_yoffset > info->output_height - info->crop_height)
++ ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
++ /* Convert negative crop offsets into regular offsets */
++ if (info->crop_xoffset_set == JCROP_NEG)
++ xoffset = info->output_width - info->crop_width - info->crop_xoffset;
++ else
++ xoffset = info->crop_xoffset;
++ if (info->crop_yoffset_set == JCROP_NEG)
++ yoffset = info->output_height - info->crop_height - info->crop_yoffset;
++ else
++ yoffset = info->crop_yoffset;
++ /* Now adjust so that upper left corner falls at an iMCU boundary */
++ info->output_width =
++ info->crop_width + (xoffset % (info->max_h_samp_factor * DCTSIZE));
++ info->output_height =
++ info->crop_height + (yoffset % (info->max_v_samp_factor * DCTSIZE));
++ /* Save x/y offsets measured in iMCUs */
++ info->x_crop_offset = xoffset / (info->max_h_samp_factor * DCTSIZE);
++ info->y_crop_offset = yoffset / (info->max_v_samp_factor * DCTSIZE);
++ } else {
++ info->x_crop_offset = 0;
++ info->y_crop_offset = 0;
++ }
+
++ /* Figure out whether we need workspace arrays,
++ * and if so whether they are transposed relative to the source.
++ */
++ need_workspace = FALSE;
++ transpose_it = FALSE;
+ switch (info->transform) {
+ case JXFORM_NONE:
++ if (info->x_crop_offset != 0 || info->y_crop_offset != 0)
++ need_workspace = TRUE;
++ /* No workspace needed if neither cropping nor transforming */
++ break;
+ case JXFORM_FLIP_H:
+- /* Don't need a workspace array */
++ if (info->trim)
++ trim_right_edge(info, srcinfo->image_width);
++ if (info->y_crop_offset != 0)
++ need_workspace = TRUE;
++ /* do_flip_h_no_crop doesn't need a workspace array */
+ break;
+ case JXFORM_FLIP_V:
+- case JXFORM_ROT_180:
+- /* Need workspace arrays having same dimensions as source image.
+- * Note that we allocate arrays padded out to the next iMCU boundary,
+- * so that transform routines need not worry about missing edge blocks.
+- */
+- coef_arrays = (jvirt_barray_ptr *)
+- (*srcinfo->mem->alloc_small) ((j_common_ptr) srcinfo, JPOOL_IMAGE,
+- SIZEOF(jvirt_barray_ptr) * info->num_components);
+- for (ci = 0; ci < info->num_components; ci++) {
+- compptr = srcinfo->comp_info + ci;
+- coef_arrays[ci] = (*srcinfo->mem->request_virt_barray)
+- ((j_common_ptr) srcinfo, JPOOL_IMAGE, FALSE,
+- (JDIMENSION) jround_up((long) compptr->width_in_blocks,
+- (long) compptr->h_samp_factor),
+- (JDIMENSION) jround_up((long) compptr->height_in_blocks,
+- (long) compptr->v_samp_factor),
+- (JDIMENSION) compptr->v_samp_factor);
+- }
++ if (info->trim)
++ trim_bottom_edge(info, srcinfo->image_height);
++ /* Need workspace arrays having same dimensions as source image. */
++ need_workspace = TRUE;
+ break;
+ case JXFORM_TRANSPOSE:
++ /* transpose does NOT have to trim anything */
++ /* Need workspace arrays having transposed dimensions. */
++ need_workspace = TRUE;
++ transpose_it = TRUE;
++ break;
+ case JXFORM_TRANSVERSE:
++ if (info->trim) {
++ trim_right_edge(info, srcinfo->image_height);
++ trim_bottom_edge(info, srcinfo->image_width);
++ }
++ /* Need workspace arrays having transposed dimensions. */
++ need_workspace = TRUE;
++ transpose_it = TRUE;
++ break;
+ case JXFORM_ROT_90:
++ if (info->trim)
++ trim_right_edge(info, srcinfo->image_height);
++ /* Need workspace arrays having transposed dimensions. */
++ need_workspace = TRUE;
++ transpose_it = TRUE;
++ break;
++ case JXFORM_ROT_180:
++ if (info->trim) {
++ trim_right_edge(info, srcinfo->image_width);
++ trim_bottom_edge(info, srcinfo->image_height);
++ }
++ /* Need workspace arrays having same dimensions as source image. */
++ need_workspace = TRUE;
++ break;
+ case JXFORM_ROT_270:
+- /* Need workspace arrays having transposed dimensions.
+- * Note that we allocate arrays padded out to the next iMCU boundary,
+- * so that transform routines need not worry about missing edge blocks.
+- */
++ if (info->trim)
++ trim_bottom_edge(info, srcinfo->image_width);
++ /* Need workspace arrays having transposed dimensions. */
++ need_workspace = TRUE;
++ transpose_it = TRUE;
++ break;
++ }
++
++ /* Allocate workspace if needed.
++ * Note that we allocate arrays padded out to the next iMCU boundary,
++ * so that transform routines need not worry about missing edge blocks.
++ */
++ if (need_workspace) {
+ coef_arrays = (jvirt_barray_ptr *)
+ (*srcinfo->mem->alloc_small) ((j_common_ptr) srcinfo, JPOOL_IMAGE,
+- SIZEOF(jvirt_barray_ptr) * info->num_components);
++ SIZEOF(jvirt_barray_ptr) * info->num_components);
++ width_in_iMCUs = (JDIMENSION)
++ jdiv_round_up((long) info->output_width,
++ (long) (info->max_h_samp_factor * DCTSIZE));
++ height_in_iMCUs = (JDIMENSION)
++ jdiv_round_up((long) info->output_height,
++ (long) (info->max_v_samp_factor * DCTSIZE));
+ for (ci = 0; ci < info->num_components; ci++) {
+ compptr = srcinfo->comp_info + ci;
++ if (info->num_components == 1) {
++ /* we're going to force samp factors to 1x1 in this case */
++ h_samp_factor = v_samp_factor = 1;
++ } else if (transpose_it) {
++ h_samp_factor = compptr->v_samp_factor;
++ v_samp_factor = compptr->h_samp_factor;
++ } else {
++ h_samp_factor = compptr->h_samp_factor;
++ v_samp_factor = compptr->v_samp_factor;
++ }
++ width_in_blocks = width_in_iMCUs * h_samp_factor;
++ height_in_blocks = height_in_iMCUs * v_samp_factor;
+ coef_arrays[ci] = (*srcinfo->mem->request_virt_barray)
+ ((j_common_ptr) srcinfo, JPOOL_IMAGE, FALSE,
+- (JDIMENSION) jround_up((long) compptr->height_in_blocks,
+- (long) compptr->v_samp_factor),
+- (JDIMENSION) jround_up((long) compptr->width_in_blocks,
+- (long) compptr->h_samp_factor),
+- (JDIMENSION) compptr->h_samp_factor);
++ width_in_blocks, height_in_blocks, (JDIMENSION) v_samp_factor);
+ }
+- break;
+ }
++
+ info->workspace_coef_arrays = coef_arrays;
+ }
+
+@@ -642,14 +1062,8 @@ transpose_critical_parameters (j_compres
+ int tblno, i, j, ci, itemp;
+ jpeg_component_info *compptr;
+ JQUANT_TBL *qtblptr;
+- JDIMENSION dtemp;
+ UINT16 qtemp;
+
+- /* Transpose basic image dimensions */
+- dtemp = dstinfo->image_width;
+- dstinfo->image_width = dstinfo->image_height;
+- dstinfo->image_height = dtemp;
+-
+ /* Transpose sampling factors */
+ for (ci = 0; ci < dstinfo->num_components; ci++) {
+ compptr = dstinfo->comp_info + ci;
+@@ -674,46 +1088,159 @@ transpose_critical_parameters (j_compres
+ }
+
+
+-/* Trim off any partial iMCUs on the indicated destination edge */
++/* Adjust Exif image parameters.
++ *
++ * We try to adjust the Tags ExifImageWidth and ExifImageHeight if possible.
++ */
+
+ LOCAL(void)
+-trim_right_edge (j_compress_ptr dstinfo)
++adjust_exif_parameters (JOCTET FAR * data, unsigned int length,
++ JDIMENSION new_width, JDIMENSION new_height)
+ {
+- int ci, max_h_samp_factor;
+- JDIMENSION MCU_cols;
++ boolean is_motorola; /* Flag for byte order */
++ unsigned int number_of_tags, tagnum;
++ unsigned int firstoffset, offset;
++ JDIMENSION new_value;
++
++ if (length < 12) return; /* Length of an IFD entry */
++
++ /* Discover byte order */
++ if (GETJOCTET(data[0]) == 0x49 && GETJOCTET(data[1]) == 0x49)
++ is_motorola = FALSE;
++ else if (GETJOCTET(data[0]) == 0x4D && GETJOCTET(data[1]) == 0x4D)
++ is_motorola = TRUE;
++ else
++ return;
++
++ /* Check Tag Mark */
++ if (is_motorola) {
++ if (GETJOCTET(data[2]) != 0) return;
++ if (GETJOCTET(data[3]) != 0x2A) return;
++ } else {
++ if (GETJOCTET(data[3]) != 0) return;
++ if (GETJOCTET(data[2]) != 0x2A) return;
++ }
+
+- /* We have to compute max_h_samp_factor ourselves,
+- * because it hasn't been set yet in the destination
+- * (and we don't want to use the source's value).
+- */
+- max_h_samp_factor = 1;
+- for (ci = 0; ci < dstinfo->num_components; ci++) {
+- int h_samp_factor = dstinfo->comp_info[ci].h_samp_factor;
+- max_h_samp_factor = MAX(max_h_samp_factor, h_samp_factor);
++ /* Get first IFD offset (offset to IFD0) */
++ if (is_motorola) {
++ if (GETJOCTET(data[4]) != 0) return;
++ if (GETJOCTET(data[5]) != 0) return;
++ firstoffset = GETJOCTET(data[6]);
++ firstoffset <<= 8;
++ firstoffset += GETJOCTET(data[7]);
++ } else {
++ if (GETJOCTET(data[7]) != 0) return;
++ if (GETJOCTET(data[6]) != 0) return;
++ firstoffset = GETJOCTET(data[5]);
++ firstoffset <<= 8;
++ firstoffset += GETJOCTET(data[4]);
+ }
+- MCU_cols = dstinfo->image_width / (max_h_samp_factor * DCTSIZE);
+- if (MCU_cols > 0) /* can't trim to 0 pixels */
+- dstinfo->image_width = MCU_cols * (max_h_samp_factor * DCTSIZE);
+-}
++ if (firstoffset > length - 2) return; /* check end of data segment */
+
+-LOCAL(void)
+-trim_bottom_edge (j_compress_ptr dstinfo)
+-{
+- int ci, max_v_samp_factor;
+- JDIMENSION MCU_rows;
++ /* Get the number of directory entries contained in this IFD */
++ if (is_motorola) {
++ number_of_tags = GETJOCTET(data[firstoffset]);
++ number_of_tags <<= 8;
++ number_of_tags += GETJOCTET(data[firstoffset+1]);
++ } else {
++ number_of_tags = GETJOCTET(data[firstoffset+1]);
++ number_of_tags <<= 8;
++ number_of_tags += GETJOCTET(data[firstoffset]);
++ }
++ if (number_of_tags == 0) return;
++ firstoffset += 2;
+
+- /* We have to compute max_v_samp_factor ourselves,
+- * because it hasn't been set yet in the destination
+- * (and we don't want to use the source's value).
+- */
+- max_v_samp_factor = 1;
+- for (ci = 0; ci < dstinfo->num_components; ci++) {
+- int v_samp_factor = dstinfo->comp_info[ci].v_samp_factor;
+- max_v_samp_factor = MAX(max_v_samp_factor, v_samp_factor);
++ /* Search for ExifSubIFD offset Tag in IFD0 */
++ for (;;) {
++ if (firstoffset > length - 12) return; /* check end of data segment */
++ /* Get Tag number */
++ if (is_motorola) {
++ tagnum = GETJOCTET(data[firstoffset]);
++ tagnum <<= 8;
++ tagnum += GETJOCTET(data[firstoffset+1]);
++ } else {
++ tagnum = GETJOCTET(data[firstoffset+1]);
++ tagnum <<= 8;
++ tagnum += GETJOCTET(data[firstoffset]);
++ }
++ if (tagnum == 0x8769) break; /* found ExifSubIFD offset Tag */
++ if (--number_of_tags == 0) return;
++ firstoffset += 12;
+ }
+- MCU_rows = dstinfo->image_height / (max_v_samp_factor * DCTSIZE);
+- if (MCU_rows > 0) /* can't trim to 0 pixels */
+- dstinfo->image_height = MCU_rows * (max_v_samp_factor * DCTSIZE);
++
++ /* Get the ExifSubIFD offset */
++ if (is_motorola) {
++ if (GETJOCTET(data[firstoffset+8]) != 0) return;
++ if (GETJOCTET(data[firstoffset+9]) != 0) return;
++ offset = GETJOCTET(data[firstoffset+10]);
++ offset <<= 8;
++ offset += GETJOCTET(data[firstoffset+11]);
++ } else {
++ if (GETJOCTET(data[firstoffset+11]) != 0) return;
++ if (GETJOCTET(data[firstoffset+10]) != 0) return;
++ offset = GETJOCTET(data[firstoffset+9]);
++ offset <<= 8;
++ offset += GETJOCTET(data[firstoffset+8]);
++ }
++ if (offset > length - 2) return; /* check end of data segment */
++
++ /* Get the number of directory entries contained in this SubIFD */
++ if (is_motorola) {
++ number_of_tags = GETJOCTET(data[offset]);
++ number_of_tags <<= 8;
++ number_of_tags += GETJOCTET(data[offset+1]);
++ } else {
++ number_of_tags = GETJOCTET(data[offset+1]);
++ number_of_tags <<= 8;
++ number_of_tags += GETJOCTET(data[offset]);
++ }
++ if (number_of_tags < 2) return;
++ offset += 2;
++
++ /* Search for ExifImageWidth and ExifImageHeight Tags in this SubIFD */
++ do {
++ if (offset > length - 12) return; /* check end of data segment */
++ /* Get Tag number */
++ if (is_motorola) {
++ tagnum = GETJOCTET(data[offset]);
++ tagnum <<= 8;
++ tagnum += GETJOCTET(data[offset+1]);
++ } else {
++ tagnum = GETJOCTET(data[offset+1]);
++ tagnum <<= 8;
++ tagnum += GETJOCTET(data[offset]);
++ }
++ if (tagnum == 0xA002 || tagnum == 0xA003) {
++ if (tagnum == 0xA002)
++ new_value = new_width; /* ExifImageWidth Tag */
++ else
++ new_value = new_height; /* ExifImageHeight Tag */
++ if (is_motorola) {
++ data[offset+2] = 0; /* Format = unsigned long (4 octets) */
++ data[offset+3] = 4;
++ data[offset+4] = 0; /* Number Of Components = 1 */
++ data[offset+5] = 0;
++ data[offset+6] = 0;
++ data[offset+7] = 1;
++ data[offset+8] = 0;
++ data[offset+9] = 0;
++ data[offset+10] = (JOCTET)((new_value >> 8) & 0xFF);
++ data[offset+11] = (JOCTET)(new_value & 0xFF);
++ } else {
++ data[offset+2] = 4; /* Format = unsigned long (4 octets) */
++ data[offset+3] = 0;
++ data[offset+4] = 1; /* Number Of Components = 1 */
++ data[offset+5] = 0;
++ data[offset+6] = 0;
++ data[offset+7] = 0;
++ data[offset+8] = (JOCTET)(new_value & 0xFF);
++ data[offset+9] = (JOCTET)((new_value >> 8) & 0xFF);
++ data[offset+10] = 0;
++ data[offset+11] = 0;
++ }
++ }
++ offset += 12;
++ } while (--number_of_tags);
+ }
+
+
+@@ -736,18 +1263,22 @@ jtransform_adjust_parameters (j_decompre
+ {
+ /* If force-to-grayscale is requested, adjust destination parameters */
+ if (info->force_grayscale) {
+- /* We use jpeg_set_colorspace to make sure subsidiary settings get fixed
+- * properly. Among other things, the target h_samp_factor & v_samp_factor
+- * will get set to 1, which typically won't match the source.
+- * In fact we do this even if the source is already grayscale; that
+- * provides an easy way of coercing a grayscale JPEG with funny sampling
+- * factors to the customary 1,1. (Some decoders fail on other factors.)
++ /* First, ensure we have YCbCr or grayscale data, and that the source's
++ * Y channel is full resolution. (No reasonable person would make Y
++ * be less than full resolution, so actually coping with that case
++ * isn't worth extra code space. But we check it to avoid crashing.)
+ */
+- if ((dstinfo->jpeg_color_space == JCS_YCbCr &&
+- dstinfo->num_components == 3) ||
+- (dstinfo->jpeg_color_space == JCS_GRAYSCALE &&
+- dstinfo->num_components == 1)) {
+- /* We have to preserve the source's quantization table number. */
++ if (((dstinfo->jpeg_color_space == JCS_YCbCr &&
++ dstinfo->num_components == 3) ||
++ (dstinfo->jpeg_color_space == JCS_GRAYSCALE &&
++ dstinfo->num_components == 1)) &&
++ srcinfo->comp_info[0].h_samp_factor == srcinfo->max_h_samp_factor &&
++ srcinfo->comp_info[0].v_samp_factor == srcinfo->max_v_samp_factor) {
++ /* We use jpeg_set_colorspace to make sure subsidiary settings get fixed
++ * properly. Among other things, it sets the target h_samp_factor &
++ * v_samp_factor to 1, which typically won't match the source.
++ * We have to preserve the source's quantization table number, however.
++ */
+ int sv_quant_tbl_no = dstinfo->comp_info[0].quant_tbl_no;
+ jpeg_set_colorspace(dstinfo, JCS_GRAYSCALE);
+ dstinfo->comp_info[0].quant_tbl_no = sv_quant_tbl_no;
+@@ -755,50 +1286,52 @@ jtransform_adjust_parameters (j_decompre
+ /* Sorry, can't do it */
+ ERREXIT(dstinfo, JERR_CONVERSION_NOTIMPL);
+ }
++ } else if (info->num_components == 1) {
++ /* For a single-component source, we force the destination sampling factors
++ * to 1x1, with or without force_grayscale. This is useful because some
++ * decoders choke on grayscale images with other sampling factors.
++ */
++ dstinfo->comp_info[0].h_samp_factor = 1;
++ dstinfo->comp_info[0].v_samp_factor = 1;
+ }
+
+- /* Correct the destination's image dimensions etc if necessary */
++ /* Correct the destination's image dimensions as necessary
++ * for crop and rotate/flip operations.
++ */
++ dstinfo->image_width = info->output_width;
++ dstinfo->image_height = info->output_height;
++
++ /* Transpose destination image parameters */
+ switch (info->transform) {
+- case JXFORM_NONE:
+- /* Nothing to do */
+- break;
+- case JXFORM_FLIP_H:
+- if (info->trim)
+- trim_right_edge(dstinfo);
+- break;
+- case JXFORM_FLIP_V:
+- if (info->trim)
+- trim_bottom_edge(dstinfo);
+- break;
+ case JXFORM_TRANSPOSE:
+- transpose_critical_parameters(dstinfo);
+- /* transpose does NOT have to trim anything */
+- break;
+ case JXFORM_TRANSVERSE:
+- transpose_critical_parameters(dstinfo);
+- if (info->trim) {
+- trim_right_edge(dstinfo);
+- trim_bottom_edge(dstinfo);
+- }
+- break;
+ case JXFORM_ROT_90:
+- transpose_critical_parameters(dstinfo);
+- if (info->trim)
+- trim_right_edge(dstinfo);
+- break;
+- case JXFORM_ROT_180:
+- if (info->trim) {
+- trim_right_edge(dstinfo);
+- trim_bottom_edge(dstinfo);
+- }
+- break;
+ case JXFORM_ROT_270:
+ transpose_critical_parameters(dstinfo);
+- if (info->trim)
+- trim_bottom_edge(dstinfo);
+ break;
+ }
+
++ /* Adjust Exif properties */
++ if (srcinfo->marker_list != NULL &&
++ srcinfo->marker_list->marker == JPEG_APP0+1 &&
++ srcinfo->marker_list->data_length >= 6 &&
++ GETJOCTET(srcinfo->marker_list->data[0]) == 0x45 &&
++ GETJOCTET(srcinfo->marker_list->data[1]) == 0x78 &&
++ GETJOCTET(srcinfo->marker_list->data[2]) == 0x69 &&
++ GETJOCTET(srcinfo->marker_list->data[3]) == 0x66 &&
++ GETJOCTET(srcinfo->marker_list->data[4]) == 0 &&
++ GETJOCTET(srcinfo->marker_list->data[5]) == 0) {
++ /* Suppress output of JFIF marker */
++ dstinfo->write_JFIF_header = FALSE;
++ /* Adjust Exif image parameters */
++ if (dstinfo->image_width != srcinfo->image_width ||
++ dstinfo->image_height != srcinfo->image_height)
++ /* Align data segment to start of TIFF structure for parsing */
++ adjust_exif_parameters(srcinfo->marker_list->data + 6,
++ srcinfo->marker_list->data_length - 6,
++ dstinfo->image_width, dstinfo->image_height);
++ }
++
+ /* Return the appropriate output data set */
+ if (info->workspace_coef_arrays != NULL)
+ return info->workspace_coef_arrays;
+@@ -816,40 +1349,108 @@ jtransform_adjust_parameters (j_decompre
+ */
+
+ GLOBAL(void)
+-jtransform_execute_transformation (j_decompress_ptr srcinfo,
+- j_compress_ptr dstinfo,
+- jvirt_barray_ptr *src_coef_arrays,
+- jpeg_transform_info *info)
++jtransform_execute_transform (j_decompress_ptr srcinfo,
++ j_compress_ptr dstinfo,
++ jvirt_barray_ptr *src_coef_arrays,
++ jpeg_transform_info *info)
+ {
+ jvirt_barray_ptr *dst_coef_arrays = info->workspace_coef_arrays;
+
++ /* Note: conditions tested here should match those in switch statement
++ * in jtransform_request_workspace()
++ */
+ switch (info->transform) {
+ case JXFORM_NONE:
++ if (info->x_crop_offset != 0 || info->y_crop_offset != 0)
++ do_crop(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
++ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_FLIP_H:
+- do_flip_h(srcinfo, dstinfo, src_coef_arrays);
++ if (info->y_crop_offset != 0)
++ do_flip_h(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
++ src_coef_arrays, dst_coef_arrays);
++ else
++ do_flip_h_no_crop(srcinfo, dstinfo, info->x_crop_offset,
++ src_coef_arrays);
+ break;
+ case JXFORM_FLIP_V:
+- do_flip_v(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays);
++ do_flip_v(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
++ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_TRANSPOSE:
+- do_transpose(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays);
++ do_transpose(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
++ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_TRANSVERSE:
+- do_transverse(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays);
++ do_transverse(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
++ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_ROT_90:
+- do_rot_90(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays);
++ do_rot_90(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
++ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_ROT_180:
+- do_rot_180(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays);
++ do_rot_180(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
++ src_coef_arrays, dst_coef_arrays);
+ break;
+ case JXFORM_ROT_270:
+- do_rot_270(srcinfo, dstinfo, src_coef_arrays, dst_coef_arrays);
++ do_rot_270(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
++ src_coef_arrays, dst_coef_arrays);
+ break;
+ }
+ }
+
++/* jtransform_perfect_transform
++ *
++ * Determine whether lossless transformation is perfectly
++ * possible for a specified image and transformation.
++ *
++ * Inputs:
++ * image_width, image_height: source image dimensions.
++ * MCU_width, MCU_height: pixel dimensions of MCU.
++ * transform: transformation identifier.
++ * Parameter sources from initialized jpeg_struct
++ * (after reading source header):
++ * image_width = cinfo.image_width
++ * image_height = cinfo.image_height
++ * MCU_width = cinfo.max_h_samp_factor * DCTSIZE
++ * MCU_height = cinfo.max_v_samp_factor * DCTSIZE
++ * Result:
++ * TRUE = perfect transformation possible
++ * FALSE = perfect transformation not possible
++ * (may use custom action then)
++ */
++
++GLOBAL(boolean)
++jtransform_perfect_transform(JDIMENSION image_width, JDIMENSION image_height,
++ int MCU_width, int MCU_height,
++ JXFORM_CODE transform)
++{
++ boolean result = TRUE; /* initialize TRUE */
++
++ switch (transform) {
++ case JXFORM_FLIP_H:
++ case JXFORM_ROT_270:
++ if (image_width % (JDIMENSION) MCU_width)
++ result = FALSE;
++ break;
++ case JXFORM_FLIP_V:
++ case JXFORM_ROT_90:
++ if (image_height % (JDIMENSION) MCU_height)
++ result = FALSE;
++ break;
++ case JXFORM_TRANSVERSE:
++ case JXFORM_ROT_180:
++ if (image_width % (JDIMENSION) MCU_width)
++ result = FALSE;
++ if (image_height % (JDIMENSION) MCU_height)
++ result = FALSE;
++ break;
++ }
++
++ return result;
++}
++
+ #endif /* TRANSFORMS_SUPPORTED */
+
+